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Abstract SUMMARY EVALUAnON OF SOME METHODS OF COTTON PLANTING IN RELA nON TO THEIR EFFECT ON YIELD AND QUALITY Two field experiments were carried out during 1986 and 1987 seasons at Bahtim Agricultural Research Station, Agricultural Research Center. The aim of the experiments was to study the effect of different planting methods and nitrogen fertilizer levels on growth, yield and fiber properties of cotton cultivar Giza 75, a medium long stable cotton. Each experiment included 18 treatments which were the combination of 6 planting methods and 3 N levels. Planting methods were : Planting seedlings of 30, 40 and 50 days old, mechanical planting at spacing of 60 cm between rows and 20 cm between hiJJs, planting by hand on both sides of ridges 120 cm width and normal planting by hand on the southern side of the ridges 60 cm in width in hills 20 cm apart. The N levels were: 25, 50 and 75 kg N/fed. A split plot design was used with 4 replications. The main plots were devoted to methods of planting and sub-plots to N levels. - 73 - The normal cultural practices were followed. Data on growth, yield components, yield, and fiber properties were recorded. Results could be summarized as follows: I. Effect of planting methods : 1. Plant height at picking time was significantly affected by planting methods in both seasons. Mechanical planting produced the tallest plants in the first season, and transplanting 40 days aged seedlings produced maximum plant height in the second season. 2. Number of fruiting branches was significantly affected by planting methods only in the second season where the greatest number of fruiting branches was produced by normal planting and the lowest number by transplanting 50 days old seedlings. Also in the second season node number of first sympodia was the highest under normal- planting and the lowest under transplanting 30 days aged seedlings. 3. Days to first flower appearance as well as to first boll opening were significantly affected by planting methods. Earlier flowering and boll opening were obtained by mechanical and normal planting and delayed flowering and boll opening were realized by transplanting 50 days old seedlings. 4. Number of total bolls/plant was significantly affected by planting methods only in the first season where transplanting 30 days old seedlings produced the highest boll number. - 74 - 5. Number of open bolls/plant was significantly affected by planting methods where the highest open boll number was obtained by planting on both sides of the ridge in both seasons and the lowest number by transplanting 50 days old seedlings. 6. Boll weight was significantly affected by planting methods In the second season where the heaviest bolls were produced by normal planting and the lightest bolls by transplanting 50 days old seedlings. 7. Seed cotton yield per plant was significantly affected by planting methods in both seasons. Growing cotton on both sides of the ridge in the first season and transplanting 30 days old seedlings in the second season-produced the highest yield/plant. 8. Lint percentage was significantly higher under normal planting in the first season arid under mechanical planting in the second one. The lowest lint percentage was obtained by tranplanting 50 days old seedlings. 9. Seed index was not affected by planting methods in both seasons. 10. Percentage of surviving hiUs was significantly higher under normal planting in the first season (96 96) and under mechanical t planting (95.6 96) in the second one. Lower percentages were recorded when seedling of 50 days old were used. Plant stand at picking foHowed a similar trend. - 75 - 11. Seed cotton yield as well as lint yield per fed. were significantly affected by planting methods in both seasons. The highest seed cotton yield was produced by normal planting in both seasons and was 9.13 and 6.48 kentar/fed. in the first and second season, respectively. The lowest seed cotton yield was produced when 50 days old seedlings were transplanted, where 3.76 and 2.51 kentar/fed. were obtained in 1986 and 1987J respectively. The lint cotton yield followed a similar trend. 12. Normal planting produced higher percentage of the first picking in both seasons, whereas transplanting aged seedlings produced the lowest percentage of first picking. 13. In both seasons fiber strength was significantly higher with normal cotton pJan~ compared with transplanting and mechanical planting. 14. Fiber length as 2.5 % span length was significantly affected by planting methods only in the second season. Mechanical planting and early transplanting positively affected this character. Span length at 50 % and uniformity ratio were not affected by planting methods. 15. Fiber fineness was positively affected by transplanting, significant differences in micronaire value were recorded in the second season in favour of transplanting. - 76 - II. Effect of’ Nitrogen Level: L Plant height, number of, fruiting branches and node number of first sympodium were not significantly affected by N level in both seasons. 2. Days to first flower appearance and to first boll openmg were greater at higher N level, indicating that higher N rates delayed flowering and maturity. 3. Total number of bolls/plant was not affected by N level in both seasons, whereas number of open bolls/plant was increased at higher N levels in the second season. 4. Boll weight increased significantly as the N level increased in the second season. 5. Seed cotton yield/plant increased significantly as the N level increased only in the second season. 6. Neither lint percentage nor seed index were significantly affected by N levels. 7. Plant stand at picking was higher at higher N level In 1987 season. 8. Seed cotton yield was significantly increased as a resuJt of increasing N level in the second season. Raising the N level from 25 to 50 and 75 kg N/fed. increased seed cotton yield by 12 and 23 %, respectively in 1987 season. Lint cotton yield followed a similar trend and increased by II and 20%, - 77 - respecti vely. 9. Percentage of first picking was reduced due to the increase in N level in both seasons. 10. Fiber strength was reduced as the N level increased in the second season. Fiber length expressed as 2.5 % span length decreased signficantly in the second season as the N level increased. 11. Fiber length as 50 % span length, uniformity ratio and micronaire values were not significantly affected by N level. III. Interaction Effects : 1. Seed cotton yield per feddan was significantly affected by the interaction planting method and N level in both seasons. The highest seed cotton yield was 9.63 kentar/fed. in 1986 produced either through planting on both sides of the ridge and 25 kg N/fed. or normal planting + 50 kg N/fed. In 1987 the highest yield was 6.95 kentar/fed. of normal planting + 75 kg N/fed. 2. Percentage of first picking was significantly affected by the interaction in the second season. The highest percentage of first picking was 78.7 % obtained by normal planting with 50 kg N/fed. |