ASSESSMENT OF GENETIC AND PHENOTYPIC VARIABILITY FOR MORPHOLOGICAL AND YIELD TRAITS IN IMPROVED WHEAT VARIETIES AND LANDRACES.

Abstract

Wheat (Triticum aestivum L.) is an important cereal crop, and the identification and utilization of genetically diverse germplasm are essential for improving grain yield and associated agronomic traits. The present study was conducted to evaluate the performance and genetic variability of wheat landraces and modern cultivars for important morphological and yield-related traits. The genotypes exhibited significant variation for plant height, spike length, spike weight, flag leaf area, grains per spike, grain weight per spike, biological yield, and grain yield, indicating the presence of substantial genetic diversity among the studied material. Plant height ranged from 47.89 to 100.67 cm, while spike length varied from 8.04 to 15.04 cm. Spike weight ranged from 2.10 to 4.89 g, and flag leaf area varied from 28.39 to 53.65. Grain yield ranged from 1741 to 5321 kg ha⁻¹, with the modern cultivar Abaseen-21 recording the highest grain yield, whereas LND-72 showed the lowest. Grain weight per spike ranged from 1.11 to 2.77 g, with LND-110 exhibiting the highest value. Biological yield varied from 5545.08 to 15075.08 kg ha⁻¹, and LND-96 produced the highest biological yield. Genetic analysis revealed that genotypic variance was generally higher than environmental variance for the evaluated traits, while genotypic coefficient of variation (GCV) was generally close to phenotypic coefficient of variation (PCV), indicating a relatively limited influence of environmental factors on trait expression. Broad-sense heritability estimates were high for most traits, ranging from 0.73 for grains per spike to 0.99 for grain weight per spike and biological yield. These findings indicate considerable genetic control of the studied traits and suggest good prospects for selection and genetic improvement. The observed variability among landraces and modern cultivars provides valuable genetic resources for wheat breeding. In particular, Abaseen-21 may be useful as a source for improving grain yield, whereas LND-110, LND-113, and LND-96 may serve as promising genetic resources for improving grain weight per spike, flag leaf area, and biological yield, respectively.