Nitrogen 2 doses 3 doses F test LSD 5%
Sucrose ---
18,9 18.5 19.4 18.9 NS
-
18.9 19.0 NS
-
Purity ----%
84.2 84.4 86.1 84.6 NS
-
84.7 84.9 NS
-
Pol ---
15.3 15.0 15.7 15.3 NS
-
15.2 15.4 NS
-
Sugar yield kg/100 kg
12.7 12.4 13.3 12.7 NS
-
12.7 12.9 NS
-
Sugar yield mt/ha 13.3 11.9 16.7 14.7
**
1.8 13.3 15.0 NS
-
WUE kg cane/m3
4.05 5.70 5.50 3.94 NS
-
4.55 5.04
** 0.31
**: Significant at 1% level.
1AFI @ 7 = Alternate furrow irrigation at 7-day intervals.
AFI @ 14 = Alternate furrow irrigation at 14-day intervals.
ISI = Improved surface irrigation.
FI = Furrow irrigation.
Table 3. Response of plant-cane characteristics to irrigation and nitrogen treatment interactions.
Inter- Stalk
N Stalk nodes/ dia- Stalk Millable Biomass Net Irrigation1 Dose height Leaves stalk meter weight stalks yield cane AFI@7
AFI@14 ISI FI
2 3 2 3 2 3 2 3
cm 217 223 212 233 270 276 273 280
10.0 9.5 11.4 11.7 11.3 9.8 10.8 9.1
--- no.
15.9 17.7 17.8 18.7 18.9 19.1 17.3 19.8
cm 2.8 2.8 3.0 3.1 2.7 2.8 2.7 -2.6
kg 0.913 0.946 0.976 1.030 1.100 1.220 1.080 0.966
1000/ha 105 120 92 98 111 107 103 124
--- 138 161 136 155 166 165 146 176
- mt/ha 95.8 114.0 89.8 101.3 122.0 107.8 110.9 119.6 F test
LSD 5 %
NS -
NS -
NS -
NS -
NS -
NS -
NS -
NS - AFI @ 7 = Alternate furrow irrigation at 7-day intervals.
AFI @ 14 = Alternate furrow irrigation at 14-day intervals.
ISI = Improved surface irrigation.
FI = Furrow irrigation.
Abou-Salama: Improving Water Use Efficiency in Sugarcane Under Upper Egypt
Table 4, Response of plant-cane quality characteristics to irrigation and nitrogen treatment interactions.
Irrigation1
AFI@7 AFI @14 ISI FI Ftest LSD 5%
N Dose 2 3 2 3 2 3 2 3
Sucrose 18.60 19.13 18.01 18.95 19.13 19.60 19.38 18.35 NS
-
Purity
%--- 83.36 85.10 82.96 85.73 86.73 85.46 85.20 83.43 NS
-
Pol ---
15.08 15.51 14.60 15.37 15.52 15.86 15.72 14.88 NS
-
Sugar yield kg/100 kg 12.39 13.00 11.90 12.95 13.22 13.38 13.26 12.21 NS
-
Sugar yield mt/ha 5.05 6.29 4.53 5.58 6.88 7.35 6.26 6.32 NS
-
WUE kg cane/m3
3.70 4.40 5.36 6.04 5.35 5.64 3.79 4.09 NS
-
1AFI @ 7 = Alternate furrow irrigation at 7-day intervals.
AFI @ 14 = Alternate furrow irrigation at 14-day intervals.
ISI = Improved surface irrigation.
FI = Furrow irrigation.
Table 5. Response of first-ratoon crop characteristics to irrigation and nitrogen treatments.
Treatment Irrigation1
AFI@7 AFI@14 ISI FI Ftest LSD 5%
Nitrogen 2 doses 3 doses F test LSD 5%
Stalk height cm 268 253 245 210
**
26 240 248 NS-
Leaves
---
10.3 9.2 8.7 8.9 NS
-
9.3 9.2 NS
-
Inter- nodes/
stalk no.
18.2 16.4 14.3 16.1
* 2.400
16.3 16.3 NS
-
Stalk diameter
cm 2.53 2.53 2.45 2.13
** 0.147
2.43 2.39 NS
-
Stalk weight
kg 0.90 0.86 0.88 0.68 NS
-
0.81 0.85 NS
-
Millable stalks
1000/ha 141 126 157 172 NS
-
146 152 NS
-
Biomass Net cane -mt/ha--- 178
150 178 169
* 19.4 153 184
* 14.9
120 120 131 114
**
10.8 109 125 NS
-
*, **: Significant and highly significant at 5 and 1 % level.
1AFI @ 7 = Alternate furrow irrigation at 7-day intervals.
AFI @ 14 = Alternate furrow irrigation at 14-day intervals, ISI = Improved surface irrigation.
FI = Furrow irrigation.
Journal American Society of Sugar Cane Technologists, Vol. 20,2000
Table 6. Response of first-ratoon crop quality characteristics to irrigation and nitrogen treatments.
Treatment Irrigation1
AFI@7 AFI @14 ISI FI Ftest LSD 5%
Nitrogen 2 doses 3 doses Ftest LSD 5%
Sucrose ---
16.4 18.0 18.0 18.3
* 1.225
17.8 17.5 NS
-
Purity
%--- 79.7 79.9 79.8 80.3 NS
-
79.5 80.3
**
0.32 Pol14.3 14.6 14.6 14.8 NS
-
14.5 14.7 NS
-
Sugar kg/100kg 11.2 11.5 11.5 11.7 NS
-
11.3 11.6
* 0.24
Sugar mt/ha 13.5 11.9 15.1 13.4
* 1.5
12.4 14.5 NS
-
WUE kg cane/m3
7.16 3.98 5.74 3.90
**
0.45 4.78 5.61 NS
-
*, **: Significant and highly significant at 5 and 1% level.
1AFI @ 7 = Alternate furrow irrigation at 7-day intervals.
AFI @ 14 = Alternate furrow irrigation at 14-day intervals.
ISI = Improved surface irrigation.
FI = Furrow irrigation.
Table 7. Response of first-ratoon crop characteristics to irrigation and N treatment interaction.
Irrigation1
N dose
Stalk Leaves Inter- height nodes
Stalk dia- meter
Stalk weight
Millable stalks
Biomass yield
Net cane AFI@7
AFI @14 ISI FI
2 3 2 3 2 3 2 3
cm 275.2 260.0 241.1 264.4 234.4 255.5 208.6 212.2
—no 10.1 10.6 8.8 9.6 8.4 8.9 10.0 7.7
./stalk—
18.0 18.5 16.2 16.6 14.2 14.4 16.8 15.5
cm 2.4 2.6 2.5 2.5 2.5 2.3 2.1 2.1
kg 0.69 1.10 0.96 0.77 0.92 0.88 0.66 0.71
1000/ha 150 132 128 123 144 170 164 181
--- 147 194 152 149 168 187 145 192
-mt/ha- 96.9 143.1 45.3 94.2 127 136 102 127 F test
LSD 5%
NS * NS NS * NS NS NS
*: Significant at 5% level.
1AFI @ 7 = Alternate furrow irrigation at 7-day intervals.
AFI @ 14 = Alternate furrow irrigation at 14-day intervals.
ISI = Improved surface irrigation.
FI = Furrow irrigation.
- 2.01 - - 0.28 - - -
Abou-Salama: Improving Water Use Efficiency in Sugarcane Under Upper Egypt
Table 8. Response of first-ratoon crop quality characteristics to irrigation and nitrogen treatment interaction.
Irrigation1
AFI@7 AFI @14 ISI FI Ftest LSD 5%
N dose 2 3 2 3 2 3 2 3
Sucrose ---
17.2 15.6 18.0 18.0 18.0 18.0 18.1 18.5 NS
-
Purity
%--- 79.1 80.3 79.7 80.0 79.3 80.3 79.9 80.6 NS
-
Pol ----
14.0 14.6 14.6 14.6 14.6 14.6 14.7 15.0 NS
-
Sugar yield kg/l00kg 10.8 11.5 11.5 11.5 11.4 11.6 11.6 11.9 NS
-
Sugar yield mt/ha 10.5 16.5 13.0 10.8 14.4 15.7 11.7 15.1 NS
-
WUE kg cane/m3
5.78 5.54 4.32 3.64 5.54 5.94 3.47 4.34 NS
-
NS: Not significant.
1AFI @ 7 = Alternate furrow irrigation at 7-day intervals.
AFI @ 14 = Alternate furrow irrigation at 14-day intervals.
ISI = Improved surface irrigation.
FI = Furrow irrigation.
Journal American Society of Sugar Cane Technologists, Vol. 20,2000
INTER-CROPPING OF FALL-PLANTED SUGARCANE WITH POTATOES AND GARLIC UNDER MIDDLE EGYPT CONDITIONS
A. M. Abou-Salama Agronomy Dept., Assiut University, Egypt
adsalama(g),acc.aun.eun.eg M.H. Aboul-Nasr Horticulture Dept., Assiut Univ., Egypt A. S. S. El-Gergawi and Nour-EIhoda M.Taha
Agric. Res. Center, Mallawi, Egypt ABSTRACT
Inter-cropping of sugarcane with potatoes and garlic was examined as a means to increase land productivity in Egypt. In an experiment conducted at Mallawi, Egypt during the 1995 to 1998 seasons, we found that cane and sugar yields of inter-cropped cane treatments were not significantly different from monocultured cane (P < 0.05), However, contrast analysis indicated that cane and sugar yields of monocultured cane were significantly greater than the mean of all the inter-cropped treatments combined. Potato and garlic yields also were significantly reduced when inter-cropped with sugarcane. All yield attributes of potatoes, except for average tuber weight, were better for potatoes planted alone. However, garlic plants inter-cropped with sugarcane seemed to be protected by cane plants from winter conditions because some of the inter-cropped garlic yield attributes, such as head diameter and clove number per head, were greater than those of the crop alone. Results indicated that inter-cropping of two rows of garlic between sugarcane rows produced the maximum LER (Land equivalent ratio) and the lowest cane Aggressiveness value (Acane_crop). This study suggests that the best cash return could be produced when a single row of potatoes, at 20 cm hill spacing, is inter-cropped with fall-planted sugarcane.
INTRODUCTION
Because of the limited amount of land available for cultivation in Egypt, it is important to maximize land use. The Egyptian farming system utilizes crop rotation to optimize production with as many as two to three crops/year. However, efforts are still required to increase productivity of limited land resources even further. Consequently, farmers are exploring inter-cropping systems.
Sugarcane is the primary source of sugar in Egypt. It is grown in an area comprising approximately 126,000 ha centered around the eight sugar factories located in Middle and Upper Egypt (Lat. 24 to 28° N). Most of the area is in small-scale farms under contract requiring farmers to plant a certain portion of their land with cane. One-fifth of the total cane area is replanted each year. This newly planted area presents farmers the opportunity to inter-crop and to obtain additional income.
Abou-Salama et al.: Inter-cropping of Fall-planted Sugarcane with Potatoes and Garlic Under Middle Egypt Conditions
Inter-cropping sugarcane has been extensively studied in India. As early as 1964, it was reported that inter-cropping would not adversely affect sugarcane yield or quality (Misra, 1964).
Furthermore, Mathure et al (1968) reported an improvement in juice quality due to inter-cropping.
Fall-planted cane was found better adapted than spring-planted cane to inter-cropping because of the slow growth rate of cane during winter (Kanwar et al 1992). Yadav (1985) indicated that inter-cropping cane would be more successful when limited to the first five months of cane growth.
Under Egyptian conditions, inter-cropping of sugarcane was tested by Nour et al. (1979) who reported a slight decrease of cane yield when inter-cropped with lentil. The lost cane income was offset by the income generated by lentil. Furthermore, El-Geddawy et al. (1988) reported that cane yield decreased up to 18.2% when inter-cropped with wheat. However, they reported an increase in Land equivalent rate (LER), calculated according to Willy and Osira (1972), of up to 73.5% with inter-cropping of three rows of wheat between cane rows compared to monocultured cane. El- Gergawi (1990) found no significant differences for juice quality due to different intercropping systems.
El-Gergawi and Abou-Salama (1994) also reported that inter-cropping of fall-planted cane is more profitable than monocultured cane. Sugarcane was found to be inter-cropped successfully with several crops: potatoes (Yin and Yang, 1993), onion (Koriem et al, 1993), mustard (Dilip et al, 1994), corn (Saini and Singh, 1994), garlic (Singh and Rai, 1996) and spices (Chaudhary et at, 1997).
Potatoes and garlic are two cash crops with short growing seasons that are grown successfully in Middle Egypt for local and foreign markets. Results of inter-cropping sugarcane with these two crops varied. Solanke et al. (1990) evaluated inter-cropped potatoes in two row spacings.
Comparisons were made to sugarcane grown as a monoculture. There were no significant differences between monocultured sugarcane and inter-cropped sugarcane with regard to cane height, number of functional leaves/main shoot, number of visible internodes/main shoot or length and girth of the middle internode. Sugarcane yields were unaffected by the different potatoes spacings. Porwal et al.
(1994) indicated that inter-cropped cane yield was the highest with garlic compared to wheat or potato.
This study was initiated to examine the effects of inter-cropping fall-planted cane with potatoes and garlic as a means of increasing profits for farmers in Middle Egypt.
MATERIALS AND METHODS
This study was conducted at the Mallawi Agricultural Experiment Station (Latitude 28°N) from 15 September 1995 to 27 January 1998. Sugarcane cultivar 'GT 9/54', potato cultivar 'Diamant' (the common cultivar in the area), and garlic cultivar 'Elbaladi' were used in this study.
The study was conducted on a loamy soil with a pH of 8,2. Available nitrogen was 68 ppm, and available phosphorus was 7 ppm. Cane was planted on 15 September 1995 and harvested on 1 February 1997 for the first season. Cane for the second evaluation was planted on 22 September 1996
Journal American Society of Sugar Cane Technologists, Vol. 20,2000
and harvested on 27 January 1998. Potatoes were planted on 10 November 1995 and 15 November 1996 and harvested on 10 March 1996 and 20 March 1997. Garlic was sown at the same planting date as potatoes in both seasons. However, the garlic was harvested on 1 April 1996 and 5 April 1997.
Seven treatments were evaluated in the study. These treatments were as follows: 1) Monocultured sugarcane planted at an inter-row spacing of 100 cm; 2) Sugarcane + single row of potatoes between cane rows at 20 cm between-hill spacing; 3) Sugarcane + single row of potatoes at 30 cm between-hill spacing; 4) Sugarcane + single row of garlic between cane rows at 20 cm between-hill spacing; 5) Sugarcane + two rows of garlic 35 cm apart between cane rows at 20 cm between-hill spacing; 6) Potatoes alone at 70 cm row spacing and 25 cm between-hill spacing; and 7) Garlic alone at 60 cm row spacing and 10 cm between-hill spacing. The experiment was a randomized complete block design with three replicates. Plot size was 21 m2.
The fertilizer program for cane was 141 kg P205/ha added as 925 kg calcium superphosphate 15.5% P205at planting. A dose of 114 kg K2O/ha supplied as 235 kg of potassium sulfate 48% K2O was added two months after planting, A total of 547 kg N/ha was added as 1176 kg of urea 46% N in two equal doses. Nitrogen applications were made two months after planting and after the harvest of the companion crop. Fertilizer requirements of 238 kg N, 71 Kg P2O5, and 114 kg K2O for potatoes and 190 kg N, 71 Kg P2O5, and 114 kg K2O/ha for garlic were added as recommended.
Standard cultural practices were followed for sugarcane, potatoes, and garlic.
To determine potato yields, a sample often hills was used to determine total tuber yield in kg, tuber yield/plant, average weight/ tuber in grams, and average number of stems per hill. To determine garlic yields, ten hills were used to determine total yield, plant height in cm, number of leaves/per plant, fresh weight of plant in grams, dry weight of plant in grams, bulb diameter in cm, and number of cloves/bulb. Plot yield was used to estimate yield in tons.
Sugarcane yields were determined by the following procedures: a sample often stalks per plot was used to measure stalk height, diameter in cm, and stalk weight in kg. The number of millable stalks and weight of clean cane per plot were used to estimate the corresponding values per hectare.
A stalk sample weighing 20 kg/ plot was drawn for juice analysis of brix, sugar % g, reducing sugars, and purity as described by Spencer and Mead (1945). Sugar yield was calculated according procedures described by Yadav and Sharma's (1980).
Land Equivalent Rate (LER) value was calculated as described by Willy and Osira (1972).
LER cane = mean inter-cropped cane yield/mean yield of monocultured cane.
LER othercrop = mean inter-cropped crop yield/mean monocultured crop yield.
L E R inter-cropped ~ L E R c a n e + L E R o t h e r c r o p-
Relative Yield Total (RYT) was calculated according to the formula outlined by Harper(1977).
RYT = mean yield of inter-cropped plant/mean yield of monocultured plant.
Aggressiveness values (A) for sugarcane were calculated according to Hall (1974).
A cane.crop = (inter-cropped cane plot yield/monocultured cane plot yield) - (inter-cropped other crop yield/monocultured yield of other crop).
Abou-Salama et al.: Inter-cropping of Fall-planted Sugarcane with Potatoes and Garlic Under Middle Egypt Conditions
All data were subjected to statistical analysis according to the methods described by Federer (1993). Means were compared using LSD (µ=0.05) according to Gomez and Gomez (1984).
Contrasts were made for the monocultured treatment cane against all inter-cropped cane treatments and for inter-cropped cane with potatoes treatments against inter-cropped cane with garlic treatments.
For potatoes and garlic, each monocultured yield was contrasted against its inter-cropped yields.
RESULTS AND DISCUSSION Sugarcane
Contrast analysis of cane (Table 1) indicated that cane alone surpassed inter-cropped cane treatments for cane yield, stalk diameter, and sugar yield. Differences in monocultured vs. inter- cropped cane were reflected by significant differences in LERcane LERinter.cropped, and Acane (Table 2).
The mean for cane alone was lower than the means of the intercropping treatments for LERinter-c:ropped
and higher for Acane.crop (Table 2). Considering the contrast between intercropping cane with either potatoes or garlic, there was a significant difference in cane stalk height (Table 1). The same contrast revealed that cane plants inter-cropped with garlic had higher LERinter_cropped and lower Acane.crop when contrasted against cane inter-cropped with potatoes (P<, 0.01) (Table 2). When individual treatments were considered for the combined analysis of variance, the only traits exhibiting highly significant differences between all intercropping treatments (P<0.01) were stalk diameter, LERinter-cropped, and Acane-crop.
Fall-planted cane growth was slow due to cold weather during fall and winter while the other crops grew well. As temperature began to rise in spring, the inter-cropped plants were harvested at the beginning of the maximum growth period of cane. The growth of cane plants occurred, without competition for the duration of the season, leading to similar yields and yield components when comparing individual cane treatments. However, significant differences in cane yield and yield components detected comparing cane alone to all intercropping treatments combined suggest that the growth of cane plants was affected by the competition with the companion crops.
Regarding LERinter_cropped, cane yield was lower in inter-cropping situations, so the increase in its value is was due to the contribution of the other crop in the inter-cropping combination. Garlic inter-cropping at one and two rows produce stepwise higher LERinter_cropped values than potatoes. This was associated with low Acane-crop for garlic inter-cropping compared to potatoes. The growth habit of the garlic plant and its leaf shape could help in reducing the Acane-crop. This also suggests that garlic would be a better crop to plant in combination with sugarcane. Relative yield total (RYT) values indicated that all systems of inter-cropping were more productive than cane alone as the value of all of them exceeded 1 (Table 2). Harper (1977) found that Relative yield total (RYT) expressed as the yield of an inter-cropped plant divided by its yield as a sole grown crop summed over all crops is a good measure of the validity of inter-cropping. If such value is equal to or smaller than 1, inter- cropping is not considered as a suitable alternative.
Cane quality parameters were not affected by the inter-cropping treatments (Table 2).
Additionally, the contrasts for quality traits also were not significant. Similar findings were reported by Nour et al.(1979), El-Gergawi (1990), and El-Gergawi and Abou-Salama (1994).
Journal American Society of Sugar Cane Technologists, Vol. 20, 2000
Potatoes
As the year effect and its interaction with the treatments were not significant, data are presented as the average of both years (Table 3). Monocultured potatoes gave the highest value of yield and all yield attributes, except for average tuber weight. Furthermore, potato inter-cropping with 20 cm hill spacing was higher in yield than the 30 cm hill spacing. Potato yield per plant was higher under wide spacing (lower number of plants). This was accompanied by a high average ruber weight per plant. However, the number of tubers per plant for both inter-cropping treatments were similarly reduced when compared to monocultured potatoes. Shading of the potato plant by the surrounding cane probably contributed to the low yields.
Land equivalent rate value was at its highest when potatoes were planted alone. However, the closest value of LER was recorded when the highest possible number of plants was inter-cropped with cane at the narrow hill spacing of 20 cm. These results suggest that planting of one row of potatoes at 20 cm hill spacing would be better than wider spacing of 30 cm. Moreover, RYT values of the 20 cm hill spacing potatoes was the only system that tends to increase productivity compared to potatoes alone while the 30 cm hill spacing inter-cropping system failed to exceed the value of 1.0 of potatoes alone.
Garlic
Monocultured garlic gave the highest total yield when compared to intercropping (Table 4).
Additionally, the two-rows inter-cropping treatment out-yielded the single-row in spite of the significant increase in all plant growth paramenters recorded for the single-row inter-cropped plants.
The high number of plants in the two rows compensated for the reduced plant growth.
Economic analysis
The data for LER inter-cropped plot indicates that inter-cropping two rows of garlic resulted in greater productivity and reduced competition with cane plants (Table 2). Cash values of the three crops in Egyptian Pounds (LE) were reported LE 95.00 for a ton of clean cane (LEI = $0.289), LE 750.00 for a ton of potatoes, and LE 850.00 for a ton of garlic during both seasons of our experiment. The cash return of the different treatments indicates that inter-cropping would provide better cash income than monoculturing cane or garlic (Figure 1).
It also indicates that the two garlic inter-cropping treatments produced less cash income for farmers than potatoes. The best cash returns were obtained from the planting of sugarcane with potatoes or potatoes alone. Inter-cropping with one row of potatoes at 20 cm between hill spacing resulted in cash income of about LE 28,286.00 compared to LE 11,966.00/ha from cane alone.
Farmers are under obligation of growing cane, so they will not be able to grow potatoes only in spite of the high cash return. The cash return for inter-cropping of cane with potatoes at a hill spacing of 30 cm was slightly less that the 20 cm spacing. However, inter-cropping with a 30 cm bill spacing will consume less tubers for seed, and the difference in cash will not cover the extra cost of seed potatoes needed for the 20 cm spacing. The small scale of farming in Egypt limits the ability to mechanical harvest crops. The average labor costs of harvesting garlic or potatoes are comparable. Thus, it may
Abou-Salama et a!.: Inter-cropping of Fall-planted Sugarcane with Potatoes and Garlic Under Middle Egypt Conditions
be concluded that intercropping of a single row of potatoes between cane rows with a hill spacing of 30 cm would be an effective way to increase the cash return of farmers contracting to grow sugarcane under Middle Egypt conditions.
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Agric. Res. 25:749-756.
9. Harper, J L. 1977. Population Biology of Plants. Academic Press, New York.
10. Kanwar, R. S., K.K. Sharma, and M.L. Kapur. 1992. Sugar cane intercropping systems in India. Sugar Cane. 6: 15-18.
11. Koriem, S.O., I. A. Farag, A.S. El-Gergawi, and F.A. A. El-Latif. 1993. Evaluation of some onion cultivars (Allium cepa L.) under different intercropping systems with sugar cane crop in middle Egypt. Assiut Journal of Agricultural Sciences. 24: 207-223.
12. Mathure, B. K., A. Singh, and V. S. Bhadawrie. 1968. Intercropping of sugarcane. Indian Sugar, 13:1043-1048.
13. Misra, G.N. 1964.Mixed cropping effects of certain intercrops on the yield and juice quality of sugarcane. Indian Sugar, 14:1-17.