CHARACTERIZATION AND DIVERSITY ANALYSIS OF TOMATO ('Solanurn lycopersicuni L.)
BY
MD. RAFIQUL ISLAM
REGISTRATION NO. 06-02076
A Thesis
Submitted to the Faculty of Agriculture.
Sher-e-Bangla Agricultural University, Dhaka, in partial thufiliment of the requirements
fhr the degree of
MASTER OF SCIENCE IN
GENETICS AND PLANT BREEDING
SEMESTER: JULY-DECEMBER, 2012
Approved by:
(Dr. Nlohammad Saiful Islam) (Dr. Naheed Zeba)
Associate Professor Professor
Supervisor Co-supervisor
(Dr. Mohainniad Saiful Islam) Chairman
Examination Committee
@r 941ohammatSafit Islam
ssociate Prof
f4 essor
(Department genetics ant 'Plant cBree&mg cDlza*g-1207, (Baizg&ztesIi
SEer-c &figricuüura(Vniversizy
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legree of9WflOcSCflZWCE in qE*ETICSflDQLfi9V'TG3cASa(DIWg. embodies the result of a piece of bonafule research wor& carriet out 6v &%iø. 'RfiTIQUL ISfJfM, Rcgist rat ion .OVb. 06-02076unter my supervision anti guitiance. 9Vb part of the thesis has been submiuecffor any otfiertegree ora'iploma.
Iflirtiler certfy that such
helpor source of information, as has Been avai&tofduring the course of this investigation has du(y been acfjwwlecigeci
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fliT praises to fl(migfit[y and XjndjislT trust on to "Omnipotent Creator"for his never-entiutzg 6('essing, it is a great pleasure to express pro/oundtfianVuIness to my respected' parents, who entileimucil Iiar&llip inspiring for prosecuting my studies, thereby receiving proper edu cation.
I
wish to express my earnest respect, sincere appreciation and enonnous inleOteLness to my reverent supervisor antthe chairman of the <Department of genetics antI 'P&znt 'Breeding, 5lzer- e'Bangli flgriculiura('University, 'Dr. sMohammad'Safiu1Is(am, ,for his scholastic supervision, helpful commentary and unvarying inspiration throughout the research work ant preparation of the thesis.
I wish to express my gratituile and best regarts to my respected Co-Supervisor, 'Dr. WaheecI Zeba, (Professor, 'Department of genetics and Plant (Breeding, Sher-e-(J3ang[a figriculiural 'University, 'DIw&a for his continuous direction, constructive criticism, encouragement and valuable suggestions in carrying out the research wora;uIpreparatioiz of this thesis.
I
am a&o highly gratefilto my honorable teachers 'Prof 'Dr. Shahutiur Rpshiti(iilzuzyan, ,Prof.
Dr. Sarcnvarl(ossain ant! (Prof 'Dr. ciroz Mafimut of the cDepartment of genetics anti 'Plant (BreedIng, Sher-e-(Bang&z figriculturat 'University, for their valuable teaching, direct and
indirect ativice, anti encouragement anti cooperat ion Luring the wlwlè stud'y period'
Ifrel to expresses my heartfelt thanky to all the teachers of the 'Department of genetics and
<Plant 'Breeding, Sfier-e-(Banglz figricultural 'University, (DIla&a for their valua&l'e suggestions
ant encouragement Luring the periotiof the stuty.
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CHARACTERIZATION AND DIVERSITY ANALYSIS OF TOMATO (Solanurn lycoperskurn L.)
BY
MD. RAFIQUL ISLAM ABS TRACT
A field experiment was conducted at the experimental field of Sher-e-Bangla Agricultural University, Dhaka. during October 2011 to April 2012. Thirty genotypes of tomato (So/anton lycopersicum L.) were studied in the present study. The objectives of the study were characterization and diversity analysis of tomato to assess the magnitude of genetic divergence in genotypes, association among the characters and their contribution to yield.
The analysis of variance indicated significantly higher amount of variability among the genotypes for all the characters. Considering genetic parameters high genotypic co- efficient of variation (GCV) was observed for number of fruits per cluster (44.55), fruit weight (59.12) and fruit yield per plant (40.52) where as days to first flowering (0.75) and days to 50% flowering (2.48) showed low GCV. in all cases, phenotypic variances were higher than the genotypic variance. High heritability with low genetic advance in percent of mean was observed for days to first flowering (DFF), days to 50% flowering . plant height (PH), number of branches per plant (BPP), number of cluster per plant (NCP), number of fruits per plant (FPP), fruit length (FL) and fruit yield per plant (FYP) which indicated that non-additive gene effects were involved for the expression of these characters and selection for such traits might not be rewarding. High heritability with high genetic advance in percent of mean were observed for number of fruits per cluster (FPC) and fruit weight (EW) indicating that there traits were under additive gene action and selection for genetic improvement for this trait would be effective. The results showed that fruit yield per plant had high positive and high significant relation with fruit weight and fruit length but high negative and significant relation with days to first flowering (l)FF) and number of clusters per plant (NCP). Days to first flowering (DFF). Days to 50% flowering. number of fruits per plant (FPP). fruit weight (FW) and fruit length (FL) had high positively direct effect on yield of tomato. So, these are found the important characters and could be used on direct selection for yield. Considering all the characters;
02 (1313-7260), 04 (80-7270). G (BD-7276). G6 (1313-7278). G15 (1313-7295), 022 (BO- 7762). G (BARI Tornato-3), G 25 (BARI Tomato-). G (BARI Tomato-7), ("27 (EARl Tomato-9), 029 (BARI Tomato-14), and G (PUSA Rubi) can be selected for future breeding program.
TABLE OF CONTENTS
CHAPTER Title Page no.
ACKNOWLEDGEMENTS i-il
ABSTRACT iii
TABLE OF CONTENTS iv-vi
LIST OF TABLES vii
LIST OF FIGURES viii
LIST OF APPENDICES ix
LIST OF ABBREVIATED TERMS x
INTRODUCTION 01-02
REVIEW OF LITERATURE 03-25
2.l.Variability 03-10
2.2. Heritability and genetic advance 11-1.4 2.3. Correlation and path co-efficient 14-23
analysis
2.4 Genetic diversity 23-25
III MATERIALS AND METHODS 26-38
3,1 Site of experiment 26
3.2 Materials 26-27
3.3 Soil and climate 28
3.4 Experimental design and layout 28
3.5 Seedbed preparation and raising of 28
seedling
3.6 Field preparation 28
3.7 Layout of the experiment 29
3.8 Land preparation 29
3. 9 Sowing and transplanting 29 3.10 Manure and fertilizer 29-31
3.11 Irrigation management 31
3.12 Intercultural operations 31
3.13 Plant protection measures 31-32 3.14 Harvesting and processing 32-33
3.15 Collection and Recorded of data 33-34
3.16. Statistical analysis 34
3.16.1. Analysis of variance 34
3.16.2. Genotypic and phenotypic variance 35 3.16.3. Genotypic and phenotypic 35
coefficient of variation
3.16.4. Estimation of heritability 36 3.16.5. Estimation of genetic advance 36
3.16.6. Correlation coefficient 36 1. ibf3ry))) 3.16.7. Path coefficient analysis 37
.3.16.8. Calculation of residual effect 37 3.16.9. Analysis of genetic divergence 37-38
LV RESULTS AND DISCUSSION 39-79
4.1. Analysis of variance 39
4.2 Variability, Heritability and Genetic 40-52 Advance
4.3. Correlation co-efficient analysis 53-62
4.4 Path coefficient analysis 63-67
4.5 Genetic diversity 68-79
4.5.1. Mahalanobis generalized distance 68-69
4.5.2. Inter cluster distance 69
4.5.3. Nearest and farthest clusters 70-71
4.5.4. Cluster mean analysis 72
4.5.5. Multivariate analysis 72
4.5.6. Principal component analysis 72
4.5.7. Non-hierarchical clustering 73 4.5.8. Contribution of characters towards 74-76
divergence of the genotypes
4.5.9. Selection of genotypes as parent for 77-78 hybridization programme
4.6 Future line of work 78-79
V SUMMARY AND CONCLUSION 80-81
VI REFERENCES 82-94
VII APPENDICES 95-96
LIST OF TABLES
Table no. Title Page no.
List of tomato genotypes with their sources
27 Doses of different fertilizers in field 31 Mean performance of various growth parameter 42-43 and yield components of I Oimportant characters
in respect of 30Lycopersicon esculentum
genotypes
Estimation of genetic parameters in ten 51 characters of 30 genotypes in tomato
Estimation of coefficients of variation, 52 heritability and genetic advance for ten
characters of 30 genotypes in tomato
Pearson correlation coefficients among different 61 pairs of yield and yield contributing characters
for different genotype of tomato
Genotypic and phenotypic correlation 62 coefficients among different pairs of yield and
yield contributing characters for different genotype of tomato
Path coefficient analysis showing direct and 67 indirect effects of different characters on yield of
tomato
Distribution of genotypes in different clusters 71 Intra (Bold) and inter cluster distances (D) for 71 3Ogenotypes
The nearest and farthest clusters from each 71 cluster between 02 values in tomato
Cluster mean values of 10 different characters of 75
30 genotypesEigen values and yield percent contribution of 10 75 characters of 30 germplasm
Relative contributions of the ten characters of 30 77
varieties to the total divergence
LIST OF FIGURES
Figure no. Title Page no
One replication view of the experimental 30 field
A single tomato plant in the experimental 30 field
A tomato plant with flower 32
A tomato plant with a cluster of tomatoes 33 Genotypic and phenotypic variability in 45 tomato
Heritability and Genetic advance over mean 46 Comparison between Eigen values and yield 76 percent contribution of 10 characters of 30
germplasm
LIST OF APPENDICES
Appendix Title Page no.
I Monthly record of air temperature, relative 95 humidity and rainfall of experimental site
during the period from October 2011 to April 2012
H Analysis of variance of 1 Oimportant 96 characters in respect of 30 Lycopersicon
esculentum genotypes
LIST OF ABBREVIATED TERMS
FULL NAME ABBREVIATION
Agro-Ecological Zone AEZ
And others er. at
Bangladesh Agricultural Research Institute BAR!
Bangladesh Bureau of Statistics BBS
Co-efficient of Variation CV
Days After Sowing DAS
Degree Celsius
Degrees of freedom d.f
Etcetera etc.
Food and Agriculture Organization FAO
Figure Fig.
Genetic Advance GA
Genotypic Co-efficient of Variation GCV Genotypic Variance
Heetare
Heritability in broad sense
ha h2b Journal
(ubrary)
Kilogram Kg
Meter m
Mean Sum of Square MSS
Millimeter mm
Muriate of Potash MP
Phenotypic Co-efficient of Variation PCV
Phenotypic variance 82-,
Randomized Complete Block Design RCBD Sher-e-Bangla Agricultural University SAU
Standard Error SE
Square meter
Triple Super Phosphate TSP
Unites Nations Development Program UNDP
CHAPTER1
INTRODUCTION
CHAPTER 1
a -
INTRODUCTION
Tomato (So/mum: /ycopersicum L.. formerly called Lvcopersicon esculentum Miller) is an economicafly and nutritionally important crop worldwide and is intensively studied model system for genetic studies in plants. Its centre of origin is presumed to be in the present state of Mexico. It is believed that the tomato was introduced in subcontinent during die British regime. It is popular for its taste, nutritional status and various uses. Various resources are accessible now for its research, which can lead to uprising in evaluation of tomato biology (Barone etal.. 2008). Many studies have been done using different genes to examine its genetic diversity (Carelli ci at, 2006. Asamizu and Ezura. 2009, Garcia- Martinez ci at, 2006; Benor et al.. 2008). Ripe fresh tomato fruit is consumed fresh as salads and consumed after cooking and utilized in the preparation of range of processed products such as puree, paste, powder, ketchup, sauce, soup and canned whole fruits.
Unripe green fruits are used for preparation of pickles and chutney. Tomatoes are important source of lycopene (an antioxidant), ascorbic acid and B-carotene and valued for their colour and tlavour.lt is a good source of vitamins (A and C) and minerals (Kalloo. 1989). It is also the dependablc source of vitamin A, B.0 and D. minerals, Ca. P and Fe. More than 7% of total vitamin-C of vegetable origin comes from tomato in Bangladesh. World volume has increased approximately 10% since 1985, reflecting a substantial increase in dietary use of the tomato. Nutritionally, tomato is a significant dietary source of minerals, vitamin A and C. organic acid and essential amino acids.The crop is adapted to a wide variety of climates ranging from the tropics to a few degree of the Arctic Circle. The present leading tomato producing countries of the world are China, United States of America. India, Egypt. Turkey, Iran, Italy. Mexico. Brazil and Indonesia (FAO. 2002). Now Bangladesh is producing a good amount of tomatoes. In Bangladesh tomato has great demand throughout the year but is available and cheaper during the winter season. In Bangladesh, it is cultivated as winter vegetable, which occupies on area of 188000 acres of land (BBS, 2005).
Thus the Average yield of tomato was 11.35 tons/ha (BBS. 2005), while it was 69.41 t/ha in USA, 21.27 t/ha in india, 31.13 t/ha in China, and 65.45 t/ha in Japan (FAO. 2004). The total production of tomatoes were 55 thousands metric tons in Bangladesh in the year of 2006-2007 (BBS, 2008). Nowadays, tomatoes are grown round the year. On the basis of these studies the quantum importance of individual characters is marked to facilitate the selection programme for better gains.
With conceiving the above scheme in mind, the present research work has been undertaken in order to fullilling the following objectives:
I) To study the nature and extent of genetic variability in tomato germplasm for growth, yield and quality parameters,
2) To assess the extent of genetic diversity and
3)To study the association of growth, earliness, yield and quality parameters in tomato germplasm.
CHAPTER 2
REVIEW OF LITERATURE
CHAPTER II
REVIEW OF LITERATURE
Vegetable breeder is primarily concerned with the improvement of both qualitative and quantitative plant characters. Hence, adequate knowledge of genetics of various traits is very essential in vegetable breeding programme for obtaining desired results in the generation. However, the success of vegetable breeding depends on the extent and the magnitude of variability existing in the germplasni. At the same time.
improvement is possible on the basis of heritable variation. Hence, for the improvement of tomato yteld traits is necessary. Therefore, detailed intbrmation about genetic architecture of fruit yield and its attributes should be the main concern.
Keeping in view the objectives of the present investigation, the review of literature concerning to the studies conducted for this dissertation is outlined under the following headings:
2.1 Variability
2.2 Heritability and genetic advance
2.3 Correlation and path co-efficient analysis 2.4 Genetic diversity
2.1 Variability
Characterization and analysis of genetic affinity among the tomato varieties are necessary before setting any program for their improvement. Moreover, several private commercial companies released various tomato varieties with different trade names. Due to non-availability of the sources and parcnts of these varieties a lot of confusions are created regarding the authenticity of these tomato germiess. To prevent trade piracy. RARI released varieties and other commercially available varieties need to be judged on the basis of their genomic information (AlameiaL. 2012)
The fundamental key to achieve the genetic improvement of a crop through a proper breeding programme is to assess the amount and nature of variation of plant characters in breeding population. It helps the breeder for improving the selection efficiency. For this reason, many researchers studied variation of various characters in tomato.
Twenty-six morphological traits as well as 47 single nucleotide polymorphism and simple sequence repeat markers were used to investigate genetic variation in 67 tomato (Solanum lycopersicuin L.) varieties collected from Argentina between 1932 and 1974. Approximately 65.0% of the morphological traits and 55.3% of the molecular markers showed polymorphisms in the 67 varieties. Average taxonomic distance between any two varieties ranged from 0.6643 to 1.1776. while Nci's genetic distance varied from 0 to 0.2022. Cluster analysis indicated that 67 varieties could be grouped into three clusters at both morphological and molecular levels. The varieties collected before 1960 had larger genetic variation than those collected after 1960.
A nurnbcr of germplasms on the basis of phenotypic characters like coloL size, taste etc. are available in tomato. In conventional breeding program, wild tomato sp ecies are widely used as sources of genes conferring resistance/tolerance to hiotic o r abiotic stresses (Kochieva es al. 2002).
The degree to which the variability of quantitative character is transmitted to the progeny is referred as heritability. As early as 1889. (ialton observed that a part of continuous variation is due to heredity. They study of heritable and non-heritable component of variability has its inception in the findings of' Johannson (1909).
Hanson et aL (2002) proposed heritability as the ratio of genotypic variance to the total variance in a non-segregating population. Since, the estimate of heritability gives indication of the amount of progress expected from selection, as they are most meaningful when accompanied by estimate of genetic advance. Genetic advance is the measure of improvement that can be achieved by practicing selection in a population.
Mahesha c/ al. (2006) carried out an experiment to study genetic variability in 30 genotypes of tomato revealed significant difference for all the characters under study and observed a wide range of variation for plant height, number of branches per plant, fruit weight. fruit length, fruit diameter, number of locules per fruit, fruit set percentage, fruits per plant, fruit yield per plant, ascorbic acid content and total soluble solids. Singh ci at (2005) conducted a field experiment on IS advance generation breeding lines of tomato, to study the variation for total soluble solids (TSS). pericarp thickness, fruit firmness, acidity. lycopene content and diy matter content and observed significant differences among the genotypes under normal conditions, whereas differences were not significant tinder high temperature conditions. The population mean was higher during November than February planting
for all the characters except acid content and TSS.
Shashikanth ci al. (2010) carried out a field experiment to study the genetic variation among 30 tomato germplasm lines and observed that the range of variation and mean valucs were high for plant height, days to 50% flowering and average fruit weight. 1-fe also observed that high genotypic variance was for most of the characters indicating a high contribution ot'the genetic component for the total variation.
2.1.1 Number of branches per plant
Shravan ci al. (2004) conducted an experiment with 30 tomato genotypes in Utter Pradesh of India during 2001/02 winter to study their genetic variability and reported significant difference for number of primary branches per plant among the genotypes Singh ci at (2002) carried out a field experiment with 92 tomato genotypes to study genetic variability and reported that the analysis of variance revealed highly significant genetic variation for plant height, number of days to tirst fruit set, number of fruit clusters per plant. number of fruits per plant, fruit weight per plant and fruit yield. The traits characterized by adequate variability may be considered in a hybridization program for yield improvement in tomato.
Singh ci at (2005) conducted a field experiment with 30 tomato and five genotypes (DT-39. RlIR-33-1, AT1-16. DARL-13 and R'I'-J013-21) showed higher number of primary branches than the control. The maximum number of fruits per plant was obtained from WE-I 17-5-3-I. Fruit yield was maximum (184 kg/plant) in 1)T-39.
Most of the cultivars showed higher total soluble solids content in their fruits compared to the control. l'he acidity percentage in fruits was highest in KS-60. The physiological loss in weight at 7 days was highest in NDT-1 11 and lowest in Plant T- 3. ATL- 13 showed the highest lycopene content (59.67 mg/l00 g).
2.1.2 Days to first flowering
Kumari ci at (2007) recorded data for total soluble solids, dry matter content.
reducing sugars. titratable acidity. ascorbic acid, lycopene, days to flowering, days to maturity, number of fruits per hunch, weight per fruit, fruit length, fruit width, number of fruit bearing branches, total number of fruits per plant, plant height, early yield and total yield and found that there were highly significant difterences for all the characters among parents except acidity, early yield, total yield and days to flowering.
Geogieva ci at (1969) reported that pre-flowering periods of the varieties ranged from 56 to 76 days. Barone ci at (2008) observed that a minimum of 66 days was necessary for first flowering for cv. Selectun-7 and a maximum of 83 days for cv.
Mtuatham in an experiment with 18 promising cultivars of tomato considering local cultivar Patharkutchi as control at Mymensingh.
Aditya ef at (1995) reported that there was no it significant difierence in days to first
flowering among the 44 genotypes which ranged between 52.67 and 58,87. Matin ci at (2001) reported significant differences among the 26 tomato genotypes for days to first flowering ranging between 49.67 and 68.33 days. The phenotypic variance was comparatively higher than the genotypic variance indicating high degrees of environmental effect for days to first flowering (Adityai 995 and Matin. 2001).
2.1.3 Plant height
Sharma and Rastogi (1993). Aditya (1995). Matin (2001) and Shravan ci al. (2004) reported significant variation for plant height. According to Aditya (1995) plant height ranged (between 48.8 and 104.2 cm while Matin ci at (2001) reported that it ranged between 70.70 and 103.80 cm.
Prasad ci at (1999) found high degrees of phenotypic and genotypic co-efficient of variation for plant height in 75 exotic genotypes of tomato. Sonone ci at (1986) and Prasad and Prasad (1 977) also reported high phenotypic and genotypic co-efficient of variation for plant height in tomato.
Aditya ci at (1995) and Matin ci at (2001) also reported that phenotypic variance was relatively higher than genotypic variance for this trait. They again observed that genotypic co-efficient of variation was lower than phenotypic co-efficient of variation indicating influence of environment for expression of this character. Joshi ci at (2004) conducted a field experimcnt with forty tomato genotypes to evaluate their genetic variability and noticed that plant height gave the highest heritability (78.82%).
2.1.4 Number of fruits per plant
Prasad and Prasad (1977), Dudi etal. (1983) and Sononc ci at (1986) reported that high genotypic and phenotypic co-efficients of variation were estimated for fruits per plant.
Rhutani ci al. (1989) performed a varietal trial of 84 genotypes and reported that Set- 23, (irowthens Globe, Punjab Chhuhara, VSII-2. Pusa Red Plum and HS 102 were the best for number of fruits per plant. Maximum genetic improvement would he possible by genetic variability for number of fruits suggested by Sidhu and Singh (1989) from their observation.
Reddy and Reddy (1990) evaluated 139 tomato genotypes and estimated phenotypic and genotypic variances, phenotypic and genotypic co-efticients of variation.
Considerable variation was observed for number of fruits per plant (4.0-296.5).
Sharma and Rastogi ci at (1993) reported significant variations for number of fruits per plant. Sahu and Mishra (1995) and Das ci al. (1998) reported wide range of genotypic variation for number of fruits per plant. They also reported high genotypic variation for number of fruits per plant.
Singh ci al. (1997) studied variability for yield related characters in 23 genotypes oi tomato and reported that phenotypic variation was quite large but genotypic variation was low. The phenotypic and genotypic co-ethcients of variation indicated that selection may be made Ibr mumber of fruits per plant
Joshi ci al. (2004) conducted a held experiment with lbrty tomato genotypes to evaluate their genetic variability and observed the number of fruits per plant gave the highest phenotypic and genotypic coefficient of variation (61.21 and 44.05, respectively) and genetic advance as percentage of mean (65.24). Mohanty ci al.
(2003) observed that the number of fruits per plant had positive direct effects on the yield and negative indirect effects on average fruit weight.
(Lit3tY)1
2.1.5 Fruit weight '-... -/ .../
...
Sonone ci al. (1986) reported that genotypic and phenotypic varianaès werhigh for individual fruit weight in the study of genetic variability with 13 genetically diverse tomato lines. Arora eLa/.( 1982) reported that a wide range of variation was observed for individual &uit weight among 4 genotypes of tomato. He also reported that genotypic co- eflicient of variation was very high for individual fruit weight in four tomato varieties namely EC32099. ItS 102, I-IS 107 and Columbia respectively.
Reddy and Reddy (1990) estimated phenotypic and genotypic variances. phenotpic and genotypic co-efiicient of variation for individual fruit weight. Considerable
variation was ohsen'cd for average individual fruit weight (1.25-158.87). Sahu and Mishra (1995) reported that fruit weight had high genotypic co-efficient of variation in 16 lines of tomato grown during the winter season of 1986 at Bhiubancswar. India.
Dudi et 0/. (1983), Das ci al. (1998) and Kuinar and l'ewari (1999) also obtained similar results in their experiments with tomato. Aditya (1995) reported that analysis of variances showed highly significant mean squares due to variety Ihr average fruit weight among the 44 varieties of tomato. (ienotypic variance associated with genotypic co-efficient of variation were smaller than phenotypic variance and phenotypic co-efficient of variation respectively.
In the study of genetic variability in 23 genotypes of tomato, Singh ci at (1997) reported that phenotypic variation was quite large but genotypic variation was low.
Brar cx aL (1998) reported that varietal differences were significant among 20 cultivars of tomato for average fruit weight ranged between 24.1g and 76.6g. Matin (2001) reported similar results for average fruit weight in an experiment with 26 tomato genotypes. Singh et al. (2002) carried out a field experiment to study genetic variability of fifteen heat tolerant tomato and showed that phenotypic (PCV) and genetic (GCV) coefficients of variation were high for average fruit weight.
Shravan et al. (2004) studied genetic variability with 30 tomato genotypes in Utter Pradesh of India and reported significant difference lbr average fruit weight among the genotypes. Mohanty ci at (2003) carried out in a field experiment to study genetic variability of 18 tomato cultivars and observed that the average fruit weight had positive direct effects on the yield and negative indirect eticcts on number of fruits per plant.
2.1.6 Yield per plant
Sachan etal. (2001) performed an experiment with certain tomato genotypes at south Guzrat, India and reported significant differences among the genotypes for yield per plant. Dudi et al. (1983) reported that phenotypic and genotypic co-efficient of
variation were high for average yield per plant. Sonone et al. (1986) reported that genotypic and phenotypic variances were high for average yield per plant.
Reddy and Reddy (1990) observed considerable variations for yield per plant in 139 tomato varieties. Aditya et at (1995) observed highly significant differences for average yield per plant among 44 genotypes of tomato. She also reported that phenotypic variance and phenotypic co- efficient of variation were higher than genotypic variance and genotypic co-efficient of variation respectively. Singh es al.
(1997) observed that phenotypic variation was quite higher than genotypic variation
for this trait in 27 genotypes of tomato.
Kumar and Tewari (1999) reported genotypic co-efficient of variation was higher for average yield per plant among 32 tomato genotypes. Brar et al. (1998) reported high degrees of variation for average yield per plant among the 186 genotypes tested.
Matin et at (2001) reported significant differences for yield per plant among the genotypes tested. He also reported that phenotypic variance was little higher than genotypic variance indicating slight environmental influence on this trait.
Singh ci at (2006) observed considerable range of genetic variability for yield, yield components and biochemical characters in the materials tinder study and maximum genotypic coefficient of variation was recorded for number of leaves per plant,
followed by number ol'clusters per plant.
2.2 heritability and genetic advance
Selection of plants on phenotypic characteristics is the most important task for all plant breeding practices. The effectiveness of selection for yield depends upon heritability. A character with high heritability gives better response to selection.
Heritability and genetic advance are the most important parameters to judge the breeding potentiality of a population for future development through selection. Many researchers have studied heritability and genetic advance of yield and many yield contributing characters of tomato. The literatures very relevant to the present study are reviewed below:
Nandpuri et at (1977) observed that heritability estimates were high for fruit size, plant 2 height and yield per plant in tomato. Expected genetic advance was also high for fruit size, yield and number of fruits per plant. Dudi c/ al. (1983) reported that heritability and A genetic advance-were high for number of fruits per plant, individual fruit weight and yield by per plant.
Sonone et at (1986) reported that heritability estimates fhr fruit number, plant height and individual fruit weight were high in tomato. lie also reported that high genetic advance (>30%) was obscrved for fruit yield, plant height, individual fruit weight and number of fruits per plant. Estimates of high heritability and high genetic advance for number of fruits per plant, individual fruit weight and plant height indicated control by additive genetic effects. Singh clot (1988) evaluated 32 genotypes for agronomic characters and obtained high heritability values for yield per plant only. Singh and Singh (1 980h) reported high heritability for average fruit weight (91.08%). total fruits (85.04%) and days to first picking (80.97%).
Kasrawi and Amr (1990) reported that ph gave comparatively higher heritability estimates in a study of seven quality characters using F populations. Reddy and Reddy (1990) studied heritability and genetic advance in 139 tomato varieties.
Heritability values for yield per plant, number of fruits per fruits per plant and average individual fruit weight were 97.99%. 95.96% and 98.46% respectively.
Aditya (1995) reported high heritability (in broad sense) with high genetic advance in percentage of mean for number of fruits per plant, individual, fruit weight and plant height. However, yield per plant showed moderate heritability and low genetic advance but highest genetic advance as percentage of mean tinder selection.
Singh et al. (1997) estimated heritability and genetic advance in 23 genotypes of tomato. High values of heritability and genetic advance indicated that effective selection may be made for fruit weight and number of fruits per plant.
Vikram and Kohli (1998) reported high heritability and genetic advance for mean fruit weight which suggested that improvement for this character should he fairly straight forward. Prasad ci al. (1999) estimated heritability in 75 exotic genotypes of tomato and reported very high heritability along with high genetic advance by fruit weight.
Brar ci at (1998) reported that the number of fruits per plant, total yield per plant and marketable yield per plant had low to moderate estimates of heritability and genetic advance and number of marketable fruits per plant had high values of heritability and
genetic advance.
Naidu etal. (1993) reported high heritability for number fruits per plant. plant height and moderate heritability for yield per plant. Matin (2001) reported high degrees of heritability and genetic advance for fruits per plant. individual fruit weight and number of seeds per fruit. Mohanty (2002) evaluated 18 genotypes of tomato and revealed high heritability with moderate to high genetic gain for average fruit weight, number of fruits per plant and plant height.
Mohanty c/ al. (2003) observed that high heritability with high genotypic coefficient of variation was for fruit weight, plant height, number of fruits and number of branches per plant. Singh (2002) reported that heritability was high for all characters except days from fruit setting to red ripe stage and the highest genetic advance was predicted for average fruit weight. followed by shelf life of red ripe fruits.
Mohanty ci al. (2003) evaluated heritability in 18 tomato eultivars and observed that high heritability with high genotypic coefficient of variation for fruit weight, plant height. number of fruits and number of branches per plant. Joshi el al. (2004) observed moderate heritability and moderate genetic gain for number of fruits per cluster, fruit length, fruit breadth, stern end sear size, number of locules per fruit, whole fruit lirmne.s.s, ascorbic acid content and plant height indicating additive gene effects. Low heritability and low genetic gain was observed for pericarp thickness.
Moderate heritability and low genetic gain for harvest duration suggests the presence of dominance and epistatic effects. High heritability combined with high genetic gain was observed for shelf life indicating additive gene action.
Shravan et at (2004) estimated heritability and genetic advance in 30 tomato genotypes for the characters like number of primary branches per plant, plant height, number of fruits per plant, fruit yield per plant and average fruit weight. The average fruit weight showed high heritabilities that ranged from 89.10% to 96.50%. The rest of the characters showed moderate heritability and low genetic advance. Moderate heritability associated with moderate genetic advance for plant height of 37 tomato genotypes of tomato were reported by Arun et al. (2004).
Singh ci al. (2005) estimated heritability and showed that heritability estimates (in the broad sense) were high for all the characters for November planting except for lycopene content. Mahesha ci at (2006) estimated heritability and expected genetic advance in 30 genotypes of tomato and observed that fruit weight, fruits per plant and plant height exhibited very high heritability values along with high genetic gain. It indicated the importance of considerable additive gene effects and therefore greater emphasis should he given on these characters while selecting the better genotypes in tomato.
Singh et a/. (2006) estimated heritability for nineteen genotypes of tomato and observed high heritability for ascorbic acid content, average weight of fruits, number of leaves per plant, number of locules per fruit, number of fruits per plant, leaf area
and dry matter content. I ugh esdmates of heritability with high genetic advance was recorded in case of number of leaves per plant. average weight of li-ui's, number of fruits per plant and plant height, whereas high heritability with low genetic advance was recorded for number of locules per fruit, dry matter content. pericarp thickness and yield per plant.
Kumari et at (2007) reported that the estimates of heritability were high for all the characteristics and genetic advance was high for plant height, moderate for total number of fruit bearing branches, weight per fruit and days to maturity, while the remaining characteristics had low values of genetic advance. Nardar ci at (2007) evaluated 20 tomato genotypes and observed high heritability with high genotypic coellicient of variation and genetic gain for 10-fruit weight, number of loculcs per fruit and fruit yield, which could be improved by simple selection.
Padda ci at (2007) observed that broad sense heritability was highest for number of fruits per plant (96.56%), followed by number of flowers per plant (93.45%).
reflecting the effectiveness of selection in the present gcrmplasm of tomato improvement. Ponnusviamy et at (2010) evaluated 12 varieties of tomato to estimate heritability and reported that high heritability coupled with high genetic advance as percentage of mean for average fruit weight. indicating the control of such character by additive gene. He also recorded that high heritability coupled with low genetic advance as percentage of mean ('or rest of the characters except pericarp thickness.
indicating most of the characters were governed by non-additive genetic components.
2.3 Correlation and path co-efficient analysis 2.3.1 Correlation between the characters
Correlation between the characters is an estimate to evaluate the inter-relationships between the characters which will help the breeders to choose selection techniques. In most cases. correlation between yield and yield contributing characters was studied as increased yield is one of the main targets of most of the breeders. Fruit yield of
tomato is the final character which is contributed by a complex chain of interrelating effects ot'different yield contributing characters.
The yield contributing characters are also interrelated among themselves. So.
association of characteristics with yield and among its components is important for planning effective selective breeding programme for maximization of yield. Such correlation studies may vary due to agro-elimatological variations from year to year.
Ifany component of yield has higher heritability than yield itself and there is positive correlation between these, then there may he some possibility of increase in the total yield by selecting that component. But, negative correlation co-efficient among yield components were generally observed indicating selection for an increase in any component might not bring improvement for yield.
Many authors have studied correlation between yield and yield contributing characters of tomato. Some pertinent recent literatures are reviewed in this section.
Dudi and Kalloo (1982) investigated yield per plant and seven yield related characters in 40 lines or tomato and observed that yield per plant and friuits per plant are positively correlated with total yield at the phenotypic level.
Mew ci. ci. (1976) studied correlation between ten characters including yield in 34 varieties/lines of tomato and observed positive correlation between yield and plant height, yield and fruit number per plant also. All three of which were positively correlated with each other and negatively correlated with weight.
Aditya (1995) studied phenotypic and genotypie correlation co-efficients to find out the associations between eight characters of 44 genotypes of tomato, She reported that yield of fruits per plant showed significant positive correlations with plant height and number of fruits per plant; and insignificant positive correlation with weight of individual fruit (phenotypically) and number of seeds per fruit.
Das et at (1998) studied correlation co- ellicient in fruit characters of tomato. They observed significant positive correlation of fruit yield per plant with number of fruits per plant. Very high and significant positive correlation co-eflicients were observed between yield and fruit weight (Prasad et a]. (999).
Dhankar et al. (2001) reported the average fruit weight under normal condition showed the highest positive effect on yield, therefore selection for average fruit weight, fruit shape index, number of fruits per plant and number of fruits per cluster is important for improvement of fruit yield. Mahalanobis et al. (2001) studied correlation co- efficient in sixty genotypes of tomato and observed a positive and significant correlation between fruit yield per plant and total soluble solids, ascorbic acid, pH and titratabe acidity and a positive and significant correlation was recorded among rind thickness, ascorbic acid and pH. They also observed similar association between total soluble solids and ascorbic acid and between titratable aciditv and p11
Kurnar etat (2003) observed that the genotypic coefficient of variation
for all characters except specitic gravity and total soluble solids (USS). ile-S6 reported that a significant positive genotypic correlation was found between pericarp thickness and juice viscosity and between lycopene and ascorbic acid contents: and locule number was negatively correlated with pericarp thickness.
Matin et al. (2001) studied phenotypic and genotypic correlations of 13 qualitative and quantitative characters of 26 genotypes of tomato and found that individual fruit weight had significant positive correlations with plant height and yield per plant. I-Ic also reported that number of fruits per plant also had significant positive correlations with fruit dry matter content and found significant negative correlations between number fruits per plant and individual fruit weight; and dry matter was negatively correlated with individual fruit weight.
Mohanty et al. (2002) reported that the phenotypic and genotypic correlations of fruit yield were significant and positive with days to first harvest, number of branches and
fruits/plant, significant and negative with plant height and average fruit weight and number of fruits per plant was inversely related with average fruit weight.
Mohanty c/ at (2002) reported that yield exhibited significantly positive phenotypic and genotypic association with number of branches per plant and number of fruits per
plant.
Naidu et al. (1993) studied correlation coefficient analysis in 13 tomato genotypes and revealed that plant height, number of branches per plant, plant spread, fresh plant weight, number of fruiting clusters, number of days to 50% Ilowering, number of fruits per clustcr, and number of fruits per plant should be considered for the enhancement of the yield of tomato.
Singh et at (2002) showed that total yield was significantly and positively correlated with marketable yield, average fruit weight. and days from fruit setting to red ripe stage.
Singh ci al. (2002) showed that the phenotypic coefficient of variation was greatest for fruit length. number of Fruits per plant, plant height, fruit weight per plant, fruit yield and number Of fruit clusters per plant and moderate for number of fruits per cluster, number of primary branches per plant. fruit diameter and total solub]e solid content.
Susie (2002) showed that a significant negative correlation was between mean fruit mass and number of fruits per plant and a significant positive correlation was found between fruit length and fruit width. The number of locules per fruit was significantly and positively correlated with fruit weight, fruit length, fruit width and number of fruits per plant.
Tiwari c/ at (2002) observed that the highest positive and significant association was between the yield and length of fruit. At the genotypic level, the highest positive association was observed between the yield and length of fruit.
Kumar c/ at (2003) observed that the number of fruits per plant had significant and positive correlation with fruit yield per plant. whereas fruit acidity had significant and positive correlation with number Of locules per fruit and average fruit weight was significantly correlated with physiological weight loss.
Kumar (2003) carried out correlation coefficient analysis of thirty diverse tomato genotypes and observed that correlation coefficients at the genotypic level were generally higher than the corresponding phenotypic ones. He also observed that yield per plant was positively and significantly associated with plant height. fruit number per plant, fruit shape index and pericarp thickness.
Pradeep ci at (2003) observed a significant negative correlation (1=-0.337) between the traits index of fruit and number of locules per fruit. A significant negative correlation was found between number of locules per fruit and dry matter content (r=- 0.271). A significant positive correlation (i0.25) was found between index of fruit and div matter content.
Prashanth (2003) reported that average fruit weight was positively and negatively correlated with total yield and it had positive and high direct effect on tota] yield (Mohanty, 2003 and Dhankhar et al.. 2001 ).Mohanty etal. (2003) studied correlation coefficient analysis of 18 tomato cultivars and reported that yield was significantly and positively correlated with number of fruits per plant and number of clays to harvest, and significantly but negatively correlated with plant height, number of branches per plant and average fruit weight and the number of fruits per plant was inversely related to average fruit weight. He also reported that most early cultivars were small fruited and low yieldcrs.
Arun Kumar ci at (2005) observed that in case of tomato yield per plant was positively and significantly correlated with average fruit weight and plant height.
Joshi et at (2004) performed correlation analysis of 37 tomato genotypes and showed that yield per plant was positively and significantly correlated with average fruit weight, fruit length. plant height and harvest duration. The average fruit weight was positively correlated with fruit length, fruit breadth, stern end scar size. pericarp thickness, whole fruit firmness and shelf life of the fruits. T-Iowcvcr, fruit weight was negatively correlated with the number of fruits per plant, number of fruits per cluster and ascorbic acid content.
Vcershetty (2004) reported that the negative association of iiurnhcr of locules per fruit on fruit yield was mainly due to its indirect positive effect via days to first flowering and average fruit weight. Patil (1998) reported negative direct effect of number of locules per fruit with fruit yield.Kumar c/ at (2006) performed correlation coefficient analysis of 30 tomato genotypes and observed that number of fruits per plant had significant and positive correlation with fruit yield per plant. whereas fruit acidity had significant and positive correlation with number of locules per fruit.
Singh et al. (2000) studied genetic parameters, inter-relationships and path co- efficient in 92 tomato genotypes. highly significant positive correlation was observed between the number of fruits per plant and yield and between plant height and number of fruits per plant while negative correlation was noticed between the number of primary branches per plant and number of fruits per plant. Mayavel ci ci. (2005a) reported that number of branches per plant had the highest positive direct effect on fruit yield. Whereas, plant height, number of fruits per cluster, number of fruits per plants and number of locules per fruit had negative direct effects on fruit yield.
Dhankhar and Dhankhar (2006) reported that number of fruits per plant had the maximum positive direct efieet.Singh and Cheema (2006) have revealed that positive direct effect of number of fruits per plant on yield was also reported by Kumar et al.
(2003). Its positive indirect effects through average fruit weight mainly contributed towards its strong association with yield. The findings were on consonance with Mohanty (2002).
Kumar c/ aL (2007) studied correlation coefficient analysis of thirty diverse tomato genotypes and noticed that correlation coefficients at the genotypic level were generally higher than the corresponding phenotypic ones and yield per plant was positively and significantly associated with plant height, fruit number per plant, fruit shape index and pericarp thickness.
Singh (2005) reported that the genotypic and phenotypic path coefficient studies depicted that number of fruits per plant had the maximum positive effect on yield Ibllowed by average fruit weight. Regarding indirect effects, it way observed that number of fruits per plant exhibited positive indirect effect towards fruit yield via number of branches per plant. it was negative via plant height. days to SO per cent flowering.
Singh ci al. (2005) carried out correlation coefficient analysis on IS advance generation breeding lines of tomato and observed that the phenotypic coefficients of variation were higher than genotypic coefficients of variation indicating that the genotypic cliect is lessened under the influence of the given cnvironment.Megha et al.
(2005) studied correlation in exotic tomato cultivars to determine the correlation of 26 tomato cultivars for number of flowers per cluster, flower clusters at first picking, number of fruits per cluster, weight per fruit, yield per plant, total yield, total soluble solids and juice percentage observed that improvement in yield could he managed by selection for number ol flowers per cluster, flower clusters at first picking, number of fruits per cluster and weight per fruit.
Kurnari ci al. (2007) observed the highest genotypic coefficient of variation for plant height followed by early yield, lycopenc content, number of fruit hearing branches and titratable acidity.Wright (2007) performed correlation analysis and observed that yield improvement can be achieved by selection for 50% flowering, plant height.
number of fruits per plant along with fruit quality characters such as lycopene, beta - carotene, ascorbic acid and titratable acidity.
Weber ci al. (2010) revealed that fruit weight, pericarp thickness, acidity. ascorbic acid and lycopene were positively and significantly associated with yield per plant, while number of fruits per plant was associated negatively.
2.3.2 Path co-efficient analysis between yield and yield contributing characters Path co-efficient is a standard tool which measures the direct influence of one character upon another and permits the separation of correlation co-efficient into components of direct and indirect effects.
Path co-efficient between yield and yield contributing characters provides an exact picture of the relative importance of direct and indirect influences of each other component characters on fruit yield. Path analysis, therefore, is a useful tool for understanding yield except chain of relationship between yield and yield contributing characters. It also provides valuable additional information for improving fruit yield via selection for its yield components.
Recent publications involving path co-efficient analysis between yield and components of yield relevant to the present study are reviewed in this section.
Dudi and KaIloo (1982) studied path analysis in tomato and reported highest direct effects of eariy yield per plant. fruit weight and fruits per plant.
Sonone ci at (1987) reported highest direct effect of plant height and fruit weight on fruit yield of tomato. Alam et al. (1988) studied path co-efficient in 19 cultivars of tomato and Ibund that maximum direct contribution towards yield was through individual fruit weight followed by number of fruits per plant. Days to first flowering has negative direct effect on yield (Oomez, 1987). McClean et at (1994) revealed that
number of fruits was the most important yield component which had direct effect on yield. Aditya ci at (1995) carried out genotypic and phenotypic path co-efficient analysis and revealed that plant height and number of fruits per plant had high positive direct effect on yield and on the other hand, weight of individual fruit had positive indirect effect on yield per plant.
Domini and Maya (1997) evaluated 18 tomato varieties for the relationship of six yield components to yield in two different seasons. They reported that fruit number per plant was the most important character having a direct effect on yield either in early sowing. Vikram and Kohli (1998) carried out an experiment with 25 genotypes of tomato and accomplished path co-efficient analysis and revealed that mean fruit weight is the most important yield contributing trait ibllowing fruits per plant.
Vineet kumar ci at (2000) conducted a field experiment to perform path analysis of yield components in thirty tomato genotypes and observed that total number of fruits per plant, average weight of fruit. thousand seed weight and number of branches per plant exhibited positive as well as high direct effects. Matin ci ci. (2001) observed that the maximum direct contribution towards yield was through individual fruit weight followed by number of fruits per plant. He also reported that days to first flowering, plant height and number of seeds per fruit had negative direct effect on yield per plant.
1-lanson et at (2002) carried out a field experiment to study path analysis of thirty- seven tomato genotypes and reported that number of fruits per cluster, average fruit weight and number of fruits per plant had direct maximum effects on fruit yield.
Mohanty ci ci (2002) performed path analysis and showed that the number of branches per plant and average fruit weight exerted high positive direct effect on yield and high positive indirect effect with each other.
hanson ci at (2002) perlbnned path analysis and revealed that number of branches, dry matter production, fruit weight. fruit length. fruit volume. TSS content, juice percentage. and number of fruits per plant exhibited positive effect on yield per plant at the genotypic and phenotypic levels, Kumar et at (2003) pertbrmed path analysis of thirty diverse tomato genotypes and indicated that fruit number per plant had the highest positive direct effect on yield per plant followed by average fruit weight.
Mohanty ci at (2003) conducted a field experiment to study path coefficient analysis of 18 tomato cultivars and observed that the number of fruits per plant and average fruit weight had positive direct effects on the yield and negative indirect effects on each other. Arun ci at (2003) revealed that the number of fruits per plant is the most important yield contributing character followed by plant height through path co- ellicient analysis. Joshi flat (2004) carried out path coefficient analysis and showed
that the number of fruits per plant is the most important yield contributing trait followed by fruit length, fruit breadth and plant height.
Kumar ci at (2003) performed path analysis of 30 tomato genotypes and reported that average fruit weight was significantly correlated with physiological weight loss.
Stngh ci al. (2004) perthrnied path analysis between yield and yield contributing characters o192 tomato genotypes and reported that number of fruits per plant exerted the high positive direct effect on yield followed by average weight per fruit, number of primary branches per plant, plant height.Singh ci at (2005) pertbrrncd path coefficient analysis and showed high positive direct effect of number of fruits per plant on yield followed by fruit diameter, average weight per iruit. fruit length, days to 50% flowering, number of fruits per cluster and days to first fruit harvest.
However. days to first fruit set, number of primaty branches per plant. plant height.
number of fruit clusters per plant and total soluble solids had direct negative effects on yield.
Kumar ci at (2006) perthrmed path coefficient analysis of thirty diverse tomato genotypes and indicated that fruit number per plant had the highest positive direct effect on yield per plant followed by average fruit weight.
2.4 Genetic divergence
In crop improvement programme, genetic divergence has been considered as an important parameter to identity most diverse parents for obtaining highly heterotic F1 generation through selection. Many scientists have studied genetic divergence of
tomato on the basis of Mahalanohis' D2-statistics based on multivariate analysis.
Among them most relevant recent publications are reviewed below:
Large morphological variations have been observed and great genetic diversity has been revealed by molecular markers in wild species (McClean & Hanson, 1986: Zhu ci al.. 2004). These variations provide great potential for crop improvement However, genetic variation in modern cultivars or hybrids is limited (Sharma &
Verma, 2001; T3enoretaL. 2008; Yi etal., 2008: Chen dat. 2009).
Landraces and local varieties contain much more genetic diversity than modern cultivars or hybrids (Terzopoulos & Reheli. 2008 and Terzopoulos ci at. 2009).
Therefore they are among the most important sources of genetic variation for breeders.
Rai es al. (1998) studied 37 tomato genotypes and could able to group them into four clusters using a non-heritable clustering approach with the help of Mahalanobis' D2 statistics for yield and yield contributing characters. The clustering pattern indicates that there was no associatior. between geographical distribution of genotype and genetic divergence characters namely number of primary branches. days to first flowering, plant height and average fruit weight contributed to maximum divergence.
Kumar and Tewari (1999) studied genetic divergence o132 tomato genotypes and could group them into 9 clusters based on D2 values. The magnitude of inter cluster distances was comparatively lower than that of inter cluster distances. Studies on genetic diversity among IS indigenous and exotic tomato cultivars for five economic characters (plant height, number of branches per plant. number of fruits per plant, average fruit weight and yield was carried out by
Sharma and Verma (2001) studied genetic divergence of 18 genotypes of tomato and grouped them into 5 clusters irrespective of geographic divergence indicating no parallelism between genetic diversity and geographical divergence. Fruit yield was
one of the three characters which played an important role in divergence between the populations.
Shashikanth ci al. (2010) carried out a field experiment to study genetic divergence of 30 tomato genotypes and observed that analysis of variance of the genotypes showed significant differences for all the characters studied indicating the existence of genotypic variation; there was no parallelism between genetic diversity and geographical divergence in tomato and suggested that high diversity among the genotypes belonging to cluster VII and X can be selected in hybridization programmes to obtain good seggregants.
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CHAPTER 3
MATERIALS AND METHODS
CJIAPTER Ill
MATERIALS AND METHODS
An experiment was carried out to study the genetic variability, heritability. genetic advance,characterization and diversity analysis of tomato (Solanurn Ivcopersicum L.) association of characters and extent of genetic divergence during Rahi 2011-12.
The material used for this study and statistical methods adopted in the investigation are presented in this chapter under the following headings.
3.1 Site of experiment
The experiment was conducted at the experimental field of Sher-e-Bangla Agricultural University. Dhaka-1207, Bangladesh during the period from October 2011 to April 2012.The experimental area was situated at 23°46' N latitude and 90°22'E longitude at an altitude of 8.6 meter above the sea level (Anon., 2006). The experimental field belongs to the Agro-ecologica
