EFFECT OF SOME WEED CONTROL PACKAGES ON SEED COTTON YIELD AND FIBER PROPERTIES OF SOME COTTON GENOTYPES (GOSSYPIUM BARBADENSE, L.) AND ITS ASSOCIATED WEEDS

Abstract

Two field experiments were conducted during 2011 and 2012 seasons at Sakha Agricultural Research Station, to investigate the performance of three cotton genotypes (Giza 86, Giza 88 and the new promising hybrid Giza 89 x 86) under some weed control packages (pendimethalin, butralin, fluazifop-p-butyl and sethoxydim) plus one hand hoeing for each herbicide in addition to the hand hoeing twice for controlling total weeds and their effects on some vegetative characters, yield components and fiber properties of cotton. Results indicated that the promising hybrid Giza 89 x 86 decreased dry weight of broad-leaved, grassy and perennial weeds by 27.6, 31.9 and 26.8% respectively, at second survey, also recorded the highest values of yield and its components, as compared to the genotype Giza 86. followed by Giza 88 in both seasons. Moreover, all weed control packages significantly decreased weeds parameters and increased yield components in both seasons. Also, gave highly significant increase in seed cotton yield (Kantar /Fadden). The highest values were obtained with (pendimethalin, butralin) plus one hand hoeing treatments, followed by hand hoeing twice and (fluazifop-p-butyl, sethoxydim) plus one hand hoeing by 66.7, 62.3, 63.7, 56.5 and 46.4 % and increased micronaire reading by 34.0, 34.0, 25.2, 30.5 and 28.0% respectively, as compared to the control treatment. The interaction between cotton genotypes and weed control packages exerted a significant integrated impact on weeds characters, and this reflected on increases in seed cotton yield components and fiber quality. From results of correlation analysis, the dry weight of total weeds biomass were negative correlated with cotton yield and micronaire reading. These results indicated that under heavily infested soil with weeds, it is better to grow the promising hybrid Giza 89 x 86 and Giza 88 with the application of weed control packages such as (pendimethalin or butralin) plus one hand hoeing or hand hoeing twice. These practices gave the highest reduction in weeds density and increased cotton yield and its components and improved yield cotton and fiber quality.