SCREENING OF COTTON CULTIVARS FOR DROUGHT TOLERANCE UNDER FIELD CONDITION

Abstract

To develop cotton germplasm with improved yield under drought conditions is one of the major goals for cotton breeders. The main purpose of this study was to evaluate 96 cotton genotypes for drought tolerance by measuring yield performance under deficit (water-limited) and full irrigation conditions. The field experiment was conducted under full (FI-100) and deficit (DI-50) irrigation conditions during the two growing seasons of 2011 and 2012 at the Agricultural Research Station of Adnan Menderes University, Aydin, Turkey. The mean data on performance of 96 different cotton genotypes showed the existance of considerable genotypic variations for yield, yield components, and drought tolerance indices. Correlation and regression analysis indicated that cotton genotypes characterizied with high GMP and low DSI could be selected as a potentially droght-tolerant genotypes. It is concluded from the present studies that, based on biplot analysis, 20 genotypes were found highly susceptile to water stress, 26 genotypes were highly susceptible to water stress but produced high yield in full irrigation, and 23 genotypes were not only water stress tolerant but also give maximum seed cotton yield. However, GC 555, Nieves, DAK-66/3, MS-30/1, Nazilli M-503, Zeta 2, Eva, NIAB 999, and Delta Diomand were found highly water stress tolerant because of maximum GMP and minimum DSI values. These genotypes could be exploited as genetic resources in breeding programs aiming to improve drought tolerance in cotton. Key words: Cotton, Gossypium hirsutum L. water stress, selection criterias