Characteristics Associated with Genetic Progress in Grain Yield in Wheat (Triticum aestivum L.)

Abstract

Increasing the yield potential of cultivars can contribute to solving the problems of climate change and the increase in world population. The objectives of this study were to study the variation of 60 wheat (Triticum aestivum L.) genotypes and to estimate the genetic progress in agronomic characters of varieties released in Mexico in the period from 1966 to 2015. The hypothesis was that the increases in yield of the genotypes are the result of the increase in the number of grains per surface unit and biomass. The study was established in six experimental stations of the National Institute of Agricultural Forestry and Livestock Research in the states of Guanajuato, Sonora, Chihuahua, Jalisco, Sinaloa, and Baja California, Mexico. Phenology, yield, and its components were measured. The treatment design was alpha lattice with two replications. The location and genotype that showed the highest yield (P≤0.01) were Baja California and COLIBRI/MONARCA, with 7309 and 5966 kg·ha−1. The average genetic gain in yield was 23.8 kg·ha−1·year−1. The grain weight increase rate was 0.21 g per year. During the period, there was no genetic progress in plant height, heading days, harvest index, grains per square meter, and ears per square meter. The increases in yield of the recent lines are due to increases in ears per square meter, grains per square meter, and biomass.