Correlation and Pathway Analysis and their Applications to Improve Yield in Bread Wheat Under Humic Acid Conditions

Abstract

This study aimed to know the relationship between growth traits and yield components with yield by studying some statistical and genetic parameters in addition to correlation and path analyses . The study included fifteen types of bread wheat (Sham 8, Aba 99, Kraita, Al_ Ezz, Aba 95, Mexibak, Sham 6, Abu Ghraib 3, Al-Fath, Intisar, Latifa, Tamouz3, Bohouth 22, and Al_Rasheed) under the influence of three levels of humic acid (0, 20 and 40 kg.h−1) using the Randomized complete block design to the arrangement of split plots with three replicates and characteristics, the number of days to heading ofspikes, the area of the flag leaf, plant height, number of active tillers, number of grains of the spike, 1000 grains weight and the total yield. The most important results were summarized as: The presence of high genetic variance compared to environmental variance, which was reflected in the high value of heritability in the broad sense, and that the coefficient of environmental variation was low compared to the coefficient of genetic and phenotypic variation, which was average, and that the expected genetic improvement as a percentage was average for all studied traits except number of days to heading trait varying levels of humic acid. We conclude from this that the third level can be considered a good and suitable environment through direct selection of the two characteristics number grains per spike and grains thousand weight to improve the yield in the future.