EVALUATING THE GENETIC INHERITANCE OF SPIKE-RELATED TRAITS IN SEGREGATING WHEAT POPULATIONS
Keywords:
wheat spike, awn, supernumerary spikelet, yield, genetic inheritanceAbstract
The global population is expected to approach 9 billion by 2050, intensifying the demand for increased food grain production. Wheat (Triticum aestivum L.), one of the world’s most important staple crops, plays a fundamental role in maintaining global food security. As wheat yield is governed by complex quantitative traits, improving spike-related characteristics, including spike length, awn development, and spikelet number, represents an important strategy for enhancing yield potential at the plant level.
This study evaluated an F₂ segregating wheat population developed from two parental lines with contrasting spike architectures to investigate the inheritance patterns and genetic variability of key spike-associated traits, including awn presence, supernumerary spikelet (SS) expression, awn length, and spike length. The F₂ population comprised 78 plants derived from a cross between Landrace-91, an awnless line with non-SS spikes, and a contrasting genotype characterized by long awns and SS spikes. Chi-square analysis was performed to assess the agreement between observed and expected segregation ratios for qualitative traits. Statistical analyses were conducted using Statistics v8.0 for least significant difference (LSD) calculations, while Microsoft Excel was used for graphical visualization.
The results revealed that both awn development and SS expression followed a 3:1 segregation ratio, indicating monogenic inheritance controlled by dominant alleles. Significant variation was observed among parental lines and F₂ progenies for quantitative traits, including awn length and spike length. Among the evaluated progenies, the 107-2-F₂ line exhibited the maximum awn length (11 cm) and spike length (22 cm). Due to its superior combination of long awns, extended spikes, and SS characteristics, the 107-2-F₂ line was selected for advancement to subsequent generations to stabilize desirable traits and improve yield potential per plant
