Evaluation of rain-fed wheat genotypes for photosynthetic contribution of inflorescence and leaves in grain yield related traits

In order to study of source limitations on traits related with wheat grain yield, an experiment was carried out in split plot design based on RCBD with four replications and 24 genotypes as the main plot factor and source limitation as subplot factor in Research Station of Dryland Agricultural Research Institute (DARI) at 2016-2017. The measured traits were spike length, number of spikelets per spike, spike weight, number of grains per spike and 1000 grains weight. The difference between the compared genotypes was significant in terms of the measured traits. Spike weight had a significant positive correlation with the number of grains per spike. The principal component analysis in control conditions, showed that all traits were placed in one principal component, that number of grains per spike was evaluated as the most effective trait. While, principal component analysis in source limitation conditions indicated that the traits are placed in two principal components, the first principal component represents the number of grains per spike and the second component represents the 1000 grains weight. Generally, both control and source limitations, the number of grains per spike was evaluated as the most effective trait. On the other hand, among the source limitations studied, flag leaf removal had the highest decrease in grain yield related traits.