Using Selection Index Technique For Improvement of Yield and Its Components in Maize (Zea may L.)

Abstract

Abstract Seven genotypes of maize (Nawroz, Saunto, Jameson, Torro, ZP-Gloria, Nahrain, and DKC6664) were planted on April 1, 2023 in the Jurgan village, Sheikhan District (45 km north of Mosul), at three levels of nano Chelated NPK fertilizer (0, 6 and 12 kg/ha-1), and under sprinkler irrigation conditions, using a randomized complete block design by a split-plot system with three replicates, to evaluate it by constructing selection indices in all possible ways among the traits included in the study (grain yield per plant, number of ears per plant, length and diameter of the ear, number of rows per ear, number of grains per row and ear, and 500 grains weight) and estimating the expected increase in grain yield per plant. The analysis of variance results showed that the mean square of the genotypes was significant for all traits. The selection index that included the traits of grain yield per plant, number of grains per row and ear, and 500 grains weight was characterized by the highest increase in relative efficiency of 20.231% compared to direct selection for grain yield per plant, an indication of the importance of selection by adopting the selection index for several traits. In the current study, this index was considered the best and was adopted in evaluating genotypes. It was found that the highest index mean was 482.624 in the ZP-Gloria genotype, with a significant difference from all other genotypes, followed in importance by DKC6664 and Torro genotypes. The local variety adopted in the study (Nahrain) came in the fourth sequence.