DEVELOPMENT OF SUMMER TOMATO PRODUCTION TECHNOLOGY TO IMPROVE YIELD AND QUALITY

DEVELOPMENT OF SUMMER TOMATO PRODUCTION TECHNOLOGY TO IMPROVE YIELD AND QUALITY

A Dissertation Submitted to the

Sher-e-Bangla Agricultural University, Dhaka In partial fulfillment of the requirements for the degree of

DOCTOR OF PHILOSOPHY BY

Md. Siddique Alam Registration No. I 1-04696

Approved by

Session: 201 l - ' 1 2

Professor Dr. d. Nazrul Islam Supervisor and Chairman

Advisory Committee Dr. Shahabuddin Ahmad %

Member Advisory Committee

Professor Dr. Md. Ismail Hossain Member

Advisory Committee

Professor Dr. Md. Rafiqul Islam Member

Advisory Committee

ii

•

¢

Dr. Md. Nazrul Islam

Professor

Department of Horticulture Sher-e-Bangla Agricultural University

Dhaka-1207

CERTIFICATE

This is to certify tat thesis entitled "DEVELOPMENT OT SUMMER TOMATO PRODUCTION TEC'ENO£OGy TO IMPROVE JIEED AND QUA£ITy" submitted to Shere­

Bangla Agricultural University, Dhaka. In partial fulfilment of the requirements for the degree of DOCTOR

OT PHCOSOP'AN IN 'HORTICULTURE, embodies the result of a piece bona fide research work carried out y Md.

Siddique am, Registration 'No. 1-04696 under my supervision and guidance. No part of this thesis as been

submitted for any other degree or diploma.

I further certify that such help or source of information, as has been availed of during the course of this investigation has duly Been acknowledged.

Dated:

Place: Dhaka, Bangladesh

iii

Professor Dr. Md. Nazrul Islam Supervisor and Chairman

Advisory Committee

I

•

ACKNOWLEDGEMENT

It is a great pleasure and privilege for the author to express his deep sense of respect, heartfelt gratitude and sincere regard to Professor Dr. Md. Nazrul Islam, Department of Horticulture, Sher-e-Bangla Agricultural University, Dhaka for his scholastic guidance, valuable suggestions, constructive criticism, instructions and inspiration during the whole period of research work and in preparing the manuscript.

The author, with deepest sense of gratitude and due respect, expresses sincere appreciation and indebtedness to Dr. Md. Shahabuddin Ahmad, Director, Horticulture Research Center, BARI, Gazipur, Professor Dr. Md. Ismail Hossain, Department of Horticulture and Professor Dr. Md. Rafiqul Islam, Department of Plant Pathology, SAU, Dhaka for their valuable advice, constant inspiration and co-operation in completion of the research work and helpful comments in reviewing the entire manuscript.

The author acknowledges with gratitude the generosity of BARI authority to provide him an in-country GOB funded scholarship and leave on deputation for completion of Ph D degree and allowing him to avail the research facilities.

His greatest debt, however, is firstly to his parents for their blessings and then to his brothers, sisters and other relatives who have made lot of sacrifice in many ways for the cause of his study and inspired him all the time.

The author likes to express his thankful appreciation to all scientists, office and field staffs of the Horticulture Research Center, BARI, Gazipur for their sincere help and co­

operation during the research work.

He is deeply indebted to his beloved wife Mrs. Fatema Khatun, daughter Tonika and son Sayan for their sacrifice, patience and encouragement that made it possible to complete his research work successfully.

The Author

%

•

DEVELOPMENT OF SUMMER TOMATO PRODUCTION TECHNOLOGY TO IMPROVE YIELD AND QUALITY

ABSTRACT

A series of experiments were carried out during the period from May 2012 to September 2014 with a view to develop potential management techniques of summer tomato cultivation for higher yield and fruit quality. Five sets of field experiments were conducted at Olericulture farm of Bangladesh Agricultural Research Institute, Gazipur, Bangladesh. The most popular summer tomato variety BARI hybrid tomato 4 was used in all the experiments. In the first experiment, pre-transplanting seedling management practices were evaluated to observe their effects on seedling quality and yield. Response of different shade intensity was measured in the second experiment. In the third experiment staking and pruning methods were standardized. Fruit thinning was done to find out the effects on fruit quality and yield in the fourth experiment. In experiment five, the treatments found most effective in previous experiments and farmer's practices were accumulated and compared in different combinations to formulate a best combined management practices. Results indicated that soil added with cocodust and cowdung in the ratio of 2: 1:2 filled in polybags produced seedlings with the highest value of seedling vigor index I & IJ (2356 and 639) as well as the highest seedling quality index (140). Accordingly, the highest stem diameter (5.45 mm), leaf number (13.7) and leaf area (159.60 cm) were obtained from the same treatment. Seedlings grown in polybags with the ratio of soil+cocodust+cowdung (2:1:2) was resulted the highest (94 %) seedling survivality in the field with the highest number of fruits per plant (39.1), yield (1.64 kg) per plant and total yield (44.37 tha).

Shade intensity influenced the growth, yield contributing characters and fruit quality.

Higher photosynthesis rate was observed in 20% to 30% shade condition in different growth stages. The highest number of marketable fruits per plant (36.1) were counted from 30% shade treatment which also produced significantly the highest yield (44.6 t/ha). The maximum fruit length (4.48 cm), fruit diameter (4.58 cm) and individual fruit weight (47.I g) were obtained from 30% shade treatment. Different shade levels showed significant effects on chemical composition of fruits. Significantly the highest number of fruits per plant (37.1), marketable fruits per plant (33.7), yield per plant (1.68 kg) and yield per hectare (44.6 t/ha) were recorded from the treatment string staking with four stems. Fruit thinning had significant effect on fruit size, physical quality and yield but had no influence on chemical content of tomato. The highest individual fruit weight (55.3

g,

fruit length (4.64 cm), diameter (4.82 cm), pericarp thickness (0.83 cm), shelf life (23 days) and fruit firmness (3.52 kg-f cm") were obtained from the treatment that retained 20 fruits per plant but treatment which retained 30 fruits per plant produced the highest yield per hectare (42.47 t/ha). Combination of the most effective treatments in previous experiments where, seedlings grown in polybags having soil+cocodust+cowdung in the ratio of 2:1:2 media, transplanted under 30%

shade and staking with string keeping four stem had a great effect on yield and profitability of summer tomato. The highest fruit set (42.65 %), number of marketable fruits per plant (36.5), the highest fruit length (4.56 cm), fruit diameter (4.67 cm), the maximum individual fruit weight (54.61 g) the highest yield per plant (1.85 kg) and yield per hectare (49.62 t/ha) were recorded from the most effective treatments combination. The maximum net return (Tk. 1098850/ha) and benefit cost ratio was 1.96 from the same treatment. The present study conclude that the developed production technology was cost effective and income generating in summer tomato.

V

CONTENTS

•

CHAPTER TITLE IPAGE

NO.

ACKNOWLEDGEMENT IV

ABSTRACT V

LIST OF TABLES vii

LIST OF FIGURES _1Xx

LIST OF PLATES _XI

LIST OF APPENDICES xii

I GENERAL INTRODUCTION ²

II REVIEW OF LITERATURE 8

Ill EXPERIMENT AND RESULTS

37

4.1. Ex.pt. I. Influence of seedling raising methods and growing

37 media on

seedling growth and yield of summer

tomato yield of summer tomato

4.2. Expt. 2. Effect of shading on microclimate, growth and 76

productivity

of summer tomato under poly tunnel

4.3. Expt. 3. Effect of different staking methods and stem pruning 107 on growth and yield of summer tomato

4.4. Expt. 4. Effect of fruit thinning on yield and quality of 128 summer tomato

4.5. Expt. 5. Yield, quality and cost efficiency of summer tomato 147 as influenced by developed production management

technology

•

IV V

SUMMARY AND CONCLUSION

REFERENCES APPENDICES

vi

160 167 190

LIST OF TABLES

TABLE TITLE PAGE

NO. NO.

1.1 Morphological characteristics of the soil of experimental site 39 1.2 Physical properties of the growing media at the start of the 41

experiment 1.3

1 .4

1.5

1.6

1.7

1.8

1.9

1 . 10

2.1

2.2

2.3

2.4 2.5

2.6

Combined effect of seedling raising methods and growing media on seedling height at 10, 15, 20 and 25 DAS

Growth parameters of tomato seedlings at the time of transplanting influenced by raising methods and growing media Fresh and dry weight of shoot and root of tomato seedling at 25 DAS influenced by raising methods and growing media during summer

Vigor index and quality index of seedlings affected by seedling raising methods and seedling growing media

Responses of seedling raising methods and seedling growing media to days to flowering, percent fruit set, days to first harvest and number of fruits per plant

Yield and yield contributing parameters as influenced by seedling raising methods and growing media during summer

Disease incidence in summer tomato as influenced by seedling raising methods and growing media

Cost and return of summer tomato as influenced by seedling raising methods and seedling growing media

Daily maximum temperatures (C) recorded inside the tunnel.

Data are averaged over each month

Daily maximum relative humidity (%) recorded inside the tunnel.

Data are averaged over each month

Mean photosynthetically active radiation (PAR), temperature, relative humidity over the growing period and their change due to shading effect

Effect of shading on flowering, fruit set, harvesting behavior and number of marketable fruits per plant of summer tomato

Effect of shading on yield and yield components of summer tomato

Effect of shading on plant biomass production of summer tomato at final harvest

vii

53 56

59

6l 67

71

73

75

89 89 90

92

94

98

TABLE NO.

2.7

2.8

2.9

2 . 1 0 2. 11 3.1

3.2

3.3

3.4

4.1

4.2

4.3

5.1

5.2

5.3

5.4

LIST OF TABLES (Cont'd.)

TITLE

Effect of shading on chlorophyll content of summer tomato at different days after transplanting

Effect of shading on chemical composition of summer tomato Effect of shading on chemical composition of summer tomato Disease incidence in summer tomato as influenced by shading Cost and return of summer tomato as influenced by shading Effects of staking type and stem pruning on days to flowering, plant height at last harvest, days to first harvest, days to last harvest, percent fruit set and number of fruits per plant of summer tomato

Effects of staking type and stem pruning on marketable fruits per, non marketable fruits per plant, individual fruit weight, fruit firmness and total soluble solid of summer tomato.

Effects of staking type and stem pruning on fruit size and yield of summer tomato

Cost and return analysis of summer tomato as influenced by staking methods and stem pruning

Effect of fruit thinning on fruit characteristics and yield of summer tomato

Effect of fruit thinning on fruit quality parameters of summer tomato

Cost and return analysis of summer tomato as influenced by fruit thinning

Effect of developed management technology on plant establishment and fruiting behavior of tomato in summer

Effect of developed management technology on fruit characters and yield of tomato in summer

Effect of developed management technology on fruit characters and yield of tomato in summer

Cost and return of summer tomato as influenced by developed management technology

viii

PAGE NO.

99

IOI 104

105 106 1 1 5

12 1

123

127

136

141

146

153

154

157

158

•

1.3

1.4

1.5

LIST OF FIGURES

Plant stand (%) affected by seedling raising method (a) and seedling growing media (b)

Plant stand influenced by seedling raising method and seedling growing media

Plant height affected by seedling raising method (a) and seedling growing media (b)

[ vF

_NO.

51 52 63

63

64

FIGURE TITLE

NO.

1. 1 Seedling height influenced by seedling raising method 1.2 Seedling height influenced by seedling growing media

1.6 Plant height affected by seedling raising method and seedling 65 growing media

2.1 Photosynthetically active radiation (PAR) measured at solar noon 88 (mmol.ms', 400 to 700 nm) inside the tunnels. Data are means

over each month

2.2 Effect of shading on plant height of summer tomato at different 9I growing stage (20,40, 60,80 DAT and at last harvest)

2.3 Effect of shading on photosynthesis (mol.CO,m's') of summer 100 tomato at different growing stage

3.1 Plant height influenced by (a) staking methods and (b) stem 1 1 3 pruning

3.2 Combined effect of staking methods and stem pruning on plant 1 1 4 height of summer tomato

3.3 Comparison of marketable and non marketable fruits influenced 118 by staking methods

3.4 Comparison of marketable and non marketable fruits influenced 1 18 by stem pruning

•

3.5 Comparison of marketable and non marketable fruits influenced 1 19 by combined effect of staking and stem pruning

ix

FIGURE NO.

LIST OF FIGURES (Cont'd.)

TITLE

I

^PAGE

NO.

4.1 Percentage of non marketable fruit per plant influenced by fruit 134 thinning treatments

4.2 Relation between individual fruit weight and fruit number per plant 135 4.3 Relation between yield per plant and fruit number per plant 138 4.4 Shelf life of tomato fruits influenced by fruit thinning treatments 140 4.5 Effect of fruit thinning on lycopene (a) and ascorbic acid content 143

(b) of tomato

4.6 Effect of fruit thinning on titratable acidity (a) and ft-carotene 145 content (b) of tomato fruit

X

•

PLATE NO.

LIST OF PLATES

TITLE [F A @ F

NO.

I.I Photographs showing poly bag (a) and seedbed preparation (b) 40 with different media

1.2

1.3

Photographs showing seedlings grown in seed bed (a) and in

polybag (b) with different growing media

Photographs of prepared field, beds (a) and polythene tunnel (b) for planting seedlings

42

43

1.4 Photograph showing leaf area meter to measure leaf area of 47 seedlings

1.5 2.1

2.2

2.3

2.4

Photograph showing seedling height influened by growing media Photographs showing shading the tunnels with agro shade nets with different shade intensity

Photographs showing measuring temperature, moisture {a) and light intensity (b) under the tunnel

Photographs showing measuring chlorophyll content (a) and photosynthesis rate (b) of tomato leaves

Photographs showing measuring surface colour (a) and shelf life (a) of tomato

52

80

81

82

83

•

3.1 Photographs showing staking tomato plants with different staking 1 10 methods

3.2 Photograph showing digital firmness tester measuring firmness of 1 12 tomato

3.3 Photographs showing number of stem related to fruit number and 126 yield per plant

4.1 Photographs showing tomato plants with 20, 25, 30 and 35 fruits 139 and also plant with no fruit thinning those affected yield

5.1 Photographs of tomato production with developed management 155 technology (a) and farmers practices (b)

XI

APPENDIX NO.

I Monthly mean BARI, Gazipur

LIST OF APPENDICES

TITLE

I

^{PAGE NO.}

weather data during the crop growing periods at 190

II Analysis of variance for seedling height of summer tomato (Expt. la) 190 UI Analysis of variance for seedling growth of summer tomato (Expt. la) 19 I IV Analysis of variance for fresh weight of shoot and root of seedling (Expt. 191

I a)

V Analysis of variance for dry weight of shoot and root of seedling (Expt. la) 191 VI Analysis of variance for seedling mortality, days to flowering, percent 192

fruit set and days to first harvest (Expt. Ib)

VII Analysis of variance for number of fruits per plant, individual fruit 192 weight and fruit length of tomato (Expt. Ib)

VIII Analysis of variance for fruit diameter, yield per plant and yield per 192 hectare (Expt. 1b)

IX Analysis of variance for disease incidence of summer tomato (Expt lb) 193 X Analysis of variance for effect of shading on plant height of summer 193

tomato (Expt. 2)

XI Analysis of variance for effect of shading on Yield contributing 193 characters of summer tomato (Expt. 2)

XII Analysis of variance for effect of shading on Yield contributing 193 characters of summer tomato (Expt. 2)

XIII Analysis of variance for effect of shading on yield and yield components 194 of summer tomato (Expt.2)

XIV Analysis of variance for effect of shading on fresh and dry weight of 194 tomato plant (Expt. 2)

XV Analysis of variance for effect of shading on chlorophyll content of 194 tomato plant (Expt. 2)

xii

LIST OF APPENDICES (Cont'd.)

APPENDIX TITLE ^PAGE

NO. ^NO.

XVI Analysis of variance for effect of shading on photosynthesis of 195 tomato plant (Expt. 2)

XVII Analysis of variance for effect of shading on quality components of 195 tomato fruit (Expt. 2)

XVIII Analysis of variance for effect of shading on disease incidence of 196 summer tomato (Expt.2)

XIX

Analysis of

variance for effect of staking methods and stem pruning 196 on growth, flowering and fruiting of summer tomato (Expt. 3)

xx

Analysis of variance for effect of staking methods and stem pruning 196 on fruit characters of summer tomato (Expt. 3)

XXI

Analysis o

f variance for effect of staking

methods an

d stem pruning 197

o

n yield

and

yield contributing characters of summer tomato (Expt.

3)

XXJI

Analysis o

f

vari ance fo

r

effec

t of fruit thinning on fruit characters of 197 summer tomato (Expt. 4)

XXJII Analysis of variance for effect of fruit thinning on yield and yield 197 contributing characters of summer tomato (Expt. 4)

XXIV Analysis of variance for effect of fruit thinning on fruit quality 197 parameters of summer tomato (Expt. 4)

XXV Analysis of variance for effect of fruit thinning on chemical 198 composition of fruit of summer tomato (Expt. 4)

XXVI

XXVII

XXVIII

Analysis of variance for effect of cultural techniques on yield 198 contributing characters of summer tomato (Expt. 5)

Analysis of variance for effect of cultural techniques on yield 198 contributing characters of summer tomato (Expt. 5)

Analysis of variance for effect of cultural techniques on fruit quality 198 characters of summer tomato (Expt. 5)

xiii

APPENDIX NO. XXIX

LIST OF APPENDICES (Cont'd.)

TITLE

Production cost (Tk/ha) of summer tomato as affected by seedling raising methods and seedling growing media (Expt. 1)

PAGE NO.

199

XXX Production cost (Tk/ha) of summer tomato as affected by 201 shading CExpt. 2)

XXXI

XXXII

XXXIII

Production cost (Tk/ha) of summer tomato as affected by 202 staking methods and stem pruning (Expt. 3)

Production cost (Tk/ha) of summer tomato as affected by fruit 204 thinning (Expt. 4)

Production cost (Tk/ha) of summer tomato as affected by 206 cultural techniques (Expt. 5)

xiv

•

•

C'CAPT'ER - I

INTRODUCTION

I

Sher•e•Bangla Agricullural Ua�

Libra5,%,g

Accession No •..•...

\\"5... 1.1 .. ,,,· ·

S�n .•.•...

y'

^{Dato: DOJ • . 'l,l)}

CHAPTER I

GENERAL INTRODUCTION

Tomato (Solanum lycopersicum L.) belongs to the family Solanaceae, originated in South America extending from Equador to Chile (Kinet and Peet. 1997). It is one of the most important vegetable crops now grown worldwide with thousands of cultivars having been selected with varying fruit types and for optimum growth in differing growth conditions. The tomato plants typically grow 1-3 m of height and have weak stem. Branching at the base is monopodial, becomes sympodial higher up. Leaves are 10 to 30 cm long and unevenly imparipinnate compound with variously indented or lobed margins. Both the stems and the leaves are slightly rough and fuzzy. The inflorescence of tomato bears small yellow flowers having five pointed lobes on the corolla. The tomato fruits are fleshy berries, green when unripe and become deep red and shiny when ripe. Tomatoes are eaten directly as raw vegetable or consumed in a variety of processed products like ketch-up, sauce, chutney etc. It is a rich source of vitamin A and C, and also contains minerals like iron, phosphorus (Kalloo, 1985). Furthermore, tomato is the richest source of antioxidant like lycopene and beta­

carotene, the compounds that protect cells from cancer. Due to the excellent nutritional and processing qualities of tomato, demand in general is growing throughout the year.

Tomato is one of the most popular vegetable crops in Bangladesh and cultivated mainly in winter (November to March) because of favorable weather. Although tomato is regarded as a day neutral plant (Kinet and Peet, 1997) but high temperature in summer (30C day/>21C night) interferes normal fertilization process and cause low fruit set (Kuo et al., 1986; Hanson, 1998a; Willits and Peet, 1998). Hence, the yield is very low in summer-rainy (hot-humid) season (from April to October). In addition, production is highly affected by heavy rainfall, excessive insects and disease damage, unavailability of quality seed and the lack of appropriate cultural practices (Villareal, 1980). At present 26316 hectare of land is under tomato cultivation both in winter and summer (BBS, 2013). The net income from summer tomato production is 4-5 times higher than winter production. So, the production area of summer tomato is increasing day by day.

The constraints that prevent farmers from achieving potential yield of tomato in summer are minimized by developing the heat tolerant varieties, use of poly runnel, grafting technology

2

•

etc. But these are inadequate because yield and quality of summer tomato i s

influenced by many other factors. High productivity

is often

depends on proper crop management practices.

This

management i s associated with quality seedling production, control of vegetative growth, reducing temperature under poly tunnel using shade, proper support to plants etc.

The

most important issue in successful vegetable production is to grow fast, strong and healthy seedlings in the shortest possible time (Rodo and Filho, 2003). Early seedling establishment o f tomato ensures uniform crop growth and

high

yield by increasing

tolerance

of the plant to diseases and adverse environmental conditions (Tur k

et al.,

2004). Techniques that will improve seedling vigour and fast seedling establishment ar e needed. In Bangladesh farmers generally grow seedlings in seedbed but on this method growth of seedlings arc not found satisfactory. Moreover. root injury during uprooting and transplanting shock cause high seedling mortality which is a barrier for successful tomato production. On t he other hand seedlings gr own in polybag are relatively tolerant

t

o physical abuse an d mishandling, more

tolerant

to post planting stress and are suitable fo r poorer sites

The use of seedling growing media constituted from a balanced mixture of several constituents could possibly another technique for healthy seedling growth. Soil or material in combination ar e usually prepared and mixed

to

form a rooting environment with adequate air-filled porosity, free from pests, diseases easily available water a

nd

suitable bulk density (Wojtusik

et al., 1994).

Locally and readily available materials such as sawdust, peanut hull.

rice hull, river sand, cocodust, farmyard manure and mixtures of these materials c an be

used

a s seedling growing media (Ayodele,

1997; Ekwu and Mbah,

2001). Different growing media that are well aerated, well drained and with good water retention capacity are used in establishing seedling in the form of sand mixed with cocodust, rice ashes, and wheat offal's (Adams

et al., 1998). Alternative seedling growing media

suc

h

as sawdust, rice bran are using

in man

y countries (Rodo an

d Filo, 2003). Therefore, a cheap and

simple

technology

of raising seedlings needs to be evolved which is appropriate and cost effective like t he use of soil, cocodust, sawdust a nd manure. Opportunities exist in the

improvement o

f seedling production system to

provide

quality seedlings without increasing costs. Interest in producing

quality seedlings

by application of improved and modern nur sery technique h as been increased in recent years (Gera and Ginwal, 2002).

3

•

•

•

Tomato is a thenno sensitive crop, the fruit set interferes

with

high day and/or night temperatures interfere

with

tomato fruit set. Incorporating genetic resistance, th e detrimental effects of high temperature on tomato fruit set has not had uniform success. Thus, cultural methods are considered essential tools for tomato production in adverse climatic condition to supply tomato fruit for existing market windows (Berry and Uddin, 1998). One practice that has been claimed t o be of benefit is shading on tomato plants during hot wea ther. Shade can increase total and marketable yield of tomato grown

in

hot climates. Tomato plants grown in Egypt for th e entire season under shade that attenuated 30

%

to 40

%

o f sunlight h ad higher yields and more fruit than those grown without shade (Abdel- Mawgoud

et al,,

1996; El­

Aidy, 1986). In Spain mobile shade was used only under intense sunlight increased marketable yield by

10% (Lorenzo et al.,

2003). The benefit o f shade on quality in th e

later

study wa s attributable to less blossom end rot and cracked skin. High light intensity can lead

t

o several disorders in development and appearance of tomato fruit that affect quality (Dorais

et al.,

2001). Sunscald injury and uneven ripening are tw o disorders brought about by direct effects of

light on

fruit. Sunscald injury of tomato fruit increased with

irradiance

and air temperature and their combined effects (Adegoroye and Jolliffe, 1987). High temperature in conjunction with high irradiance also contributed to blotchy o r uneven ripening (Lipton, 1970). Cracks i n the skin are one of the most common defects of tomatoes (Peet an d Willis,

1995).

Sunlight plays a

role

in this de fect. Field-grown fruit exposed to sunlight were more than twice as

likely to

develop cracks as shaded fruit (Whaley-Emmons and Scott,

1997).

Yields of summer tomato do not always reach th e full production potential. This is probably because of inadequate management.

Improved

management such as staking and pruning could improve the yield of tomatoes. Staking refers to support of plants with sturdy material to keep the fruits and foliage off the ground. The benefit of staking is t o improve fruit quality by keeping fruit off the ground and increasing air flow thr ough the plant. A proper staking method c an also make tomatoes easier to harvest and provides bette r spray coverage.

However, staking systems

require an investment in materials an d labor, so the benefits of these cos ts must be evaluated. Several

tomato staking methods exist

in Bangladesh of which inverted 'V' shaped staking is most common. Nowadays, f armers are using high platform system in some areas.

I

n many countries tomato plants are staked b y jute or nylon string

4

•

•

hanging from the top of the tunnel which is less costly. So, these three staking systems for summer grown

tomatoes should

be evaluated

t

o determine yield and cost efficiency.

Pruning in tomatoes has been reported to increase yields and quality (Hadfield,

1989;

Preece

et al., 1995;

Srinivasan,

et al.,

2001).

In order

to maximize the efficiency of photosynthesis and minimize the risk of diseases pruning is necessary when the growth is extremely dense.

If mor e stems arc allowed to develop, some of the precious sugar is diverted from fruit to multiple growing

tips which results smaller fruits.

In general. more stem means more but smaller fruits. Franco

et al.

(2009) stated tha t choosing a proper pruning system was important t o keep a balance

i

n the relationship between source/sink and the carbon/nitrogen (C/N) ratio. There are several reports that confirm the benefits of pruning on tomato yields.

Cockshull

et al.

(2001) found a tendency for side shoots to reduce the yield of marketable fruit produced on each cluster in greenhouse production. Guan and Janes (1991) also reported that pruning tomato plants

regulate N: CHO

ratio within the plant, and enhance fruiting.

Pruning

requirements differ depending on the growth habit of the cultivar, but typically

it

i s recommended that indeterminate greenhouse tomatoes b e pruned to one stem by

removing all

side shoots (Snyder, 2007).

However, literature indicates

that productivity per

unit area

increases when pruning tomatoe plants to two stems. Aung (1999) reported that greater marketable yield was obtained

by

pruning

indeterminate

tomatoes

to two stems rather than

one stem.

Yield, quality and fruit size of

tomatoes are

influenced by many factors, including fruit pruning (Saglam & Yazgan, 1999; Ghebremariam, 2005).

An

increase i n total number of

flowers

and fruits has been shown

to increase competition for photosynthate and thus,

decrease fruit size (Veliath & Ferguson, 1972). Additionally, plants that are subjected

to

high fruit

load

or sink: source ratio often results in abortion of flower or fruit (Marcelis,

1994;

Bertin, 1995). Hanna (2009) found that pruning clusters to

three fruits significantly increased tota

l

marketable yield,

reduced cull yield,

and increased fruit weight. Fruit thinning can also increase fruit quality of tomato without spending too much money and harmful chemicals.

Tabasi

et al.

(2011) stated that fruit thinning affect significantly on the

levels of ascorbic

acid, soluble solids and carotenoid, while n o major difference was observed on fruit lycopene

5

levels. Domin and

Kempton (1975) reported that fruit thinning

leads

t

o produce big fruit and raised dry matter and

soluble solids content of fruits. Bradly (1964) and Mauz (1966)

expressed

that

there is a negative relation between ascorbic acid and the number of fruit on the plant, while this relation is observed positively between ascorbic acid and leaf fruit ratio.

Tomato become very popular in Bangladesh and got a

good demand

throughout

the year.

So the production area of

summer tomato is expanding faster.

For

successful cultivation

of tomato during

summer, improved

cultural practices should be evolved

t

o increase yield and quality to

get maximum profit.

Studies

have been carried out

on crop management like

seedling

raising method and media, use of

shade, staking

method, stem pruning and fruit thinning for

summer tomato production in

other

countries.

But in

Bangladesh, research

works i n these aspects are inadequate and not

conclusive. Therefore,

a

series

of

studies

were

undertaken

with the following objectives:

i)

T

o study the effects o

f

seedling

raising methods and growing media on the growth and quality of

seedling

in

summer

tomato.

ii)

To find out the shading effect on

growth,

yield and quality of tomato in

summer season.

iii)

To determine th

e influence of stem

pruning and

staking type on the summer

tomato production.

iv) T o assess the

yield and fruit quality as

affected by fruit thinning.

v) To workout the economics of tomato cultivation for various management

practices.

6