Direct and indirect effects of several wheat traits on grain yield

Abstract

A detailed analysis of wheat traits has contributed to the greater efficacy of breeding for yield components as opposed to breeding for yield per se. The determination of correlations and direct and indirect effects among wheat traits has made it possible to achieve a better understanding of their interrelationships as well as their better balancing for improved yield per unit area. Forty-four divergent genotypes were analyzed in the paper. Highly significant correlations were found between plant height and spike length, grain number per spike and yield per plant, 1000-grain weight and yield per plant, and spike index and harvest index. Between harvest index and plant height and spike length there was a highly significant negative correlation. Path analysis revealed highly significant direct effects of grain number per spike and 1000-grain weight on grain yield per plant. The observed negative direct effect of spikelet number per spike on plant yield indicates the need to increase spikelet fertility.

Detaljna analiza pojedinih svojstava pšenice doprinela je većoj efikasnosti oplemenjivanja na komponente prinosa u odnosu na prinos per se. Utvrđivanje korelativnih odnosa, kao i direktnih i indirektnih efekata, omogućilo je lakše sagledavanje međusobnih veza i njihovo balansiranje u cilju unapređenja prinosa po jedinici površine. U radu su analizirana 44 divergentna genotipa. Utvrđena je visoko značajna korelativna veza između visine biljke i dužine klasa, broja zrna po klasu i prinosa po biljci, mase 1000 zrna i prinosa po biljci, kao i indeksa klasa i žetvenog indeksa. Visoko značajna negativna korelacija utvrđena je između žetvenog indeksa i visine biljke i dužine klasa. Path analizom utvrđeni su visokoznačajni direktni efekti broja zrna po klasu i mase 1000 zrna na prinos zrna po biljci. Negativan direktni efekat broja klasića po klasu na prinos biljke ukazao je na potrebu unapređenja njihove fertilnosti.