Evaluation of Cotton Genotypes Through the Selection Index Technique

Abstract

Eight upland cotton genotypes introduced from different origins (BA440, FLASH, EDESSA, SPERO, IK259, W888, MONTANA and CANDIA) in addition to the two local cultivars (Coker 310 and Lachata) were cultivated on April 22 and 23, 2022 in the Rahmaniyah region at levels (0, 1, 2, and 3 g/liter). l) of nano-chelated NPK 20-20-20 under drip irrigation conditions, and using a randomized complete block design with three replications, in order to evaluate it by creating multiple selection indices and to estimate the expected increase in seed cotton yield. The results of the analysis of variance for the studied traits (seed cotton yield, plant height, number of fruiting per plant, number of bolls per plant, average boll weight, seed index, and lint index) showed that the mean square of genotypes and levels of nano-fertilizer and their interaction was highly significant for all traits except seed index in case of nano-fertilizer levels. The selection index that included the two traits of plant height and number of bolls per plant was characterized by a high increase in efficiency compared to direct selection of the seed cotton yield, indicating the importance of selection by adopting the selection index for several traits. This selection index in the current study was considered the best due to its high efficiency, and by adopting it in evaluating the genotypes, it was found that the highest mean of the index was 7.689 for the CANDIA genotype, with a significant difference from most other genotypes, followed by the FLASH and BA440 genotypes. The sequence of local varieties adopted in the study (Coker 310 and Lachata) in terms of performance was 10 and 7, respectively. It appeared that six introduced genotypes were superior to the best local cultivars (Lachata), and all introduced genotypes were higher than the least performing local variety (Coker 310).