A diallel cross among drought tolerant maize populations

Abstract

A complete diallel without reciprocals was investigated among six drought tolerant maize (Zea mays L.) landraces from MRI Zemun Polje gene bank. Trials with parental populations, their crosses and three check hybrids were conducted at three locations in 2012 and five locations in 2013 in Serbia. The aim was to determine potential heterotic patterns for reciprocal recurrent selection (RRS) among them. The average grain yield reached 4.832 and 5.864 t ha(-1) for the populations and population crosses, respectively. Mipdarent heterosis (MPH) for grain yield ranged from 10.0 to 36.7 %, with the average value of 21.3 %. Entry x environment interactions did not show significance for any trait, reflecting a broader adaptation of the material to different environments. The new heterotic pattern proposed for RRS was Iranian dent POP. N-425 x Argentinean flint ARZM 06-020, which had the highest grain yield (6.871 t ha(-1)) and MPH value (36.7 %). This cross confirms the hypotesis that broader geographical origin, as well as dent x flint type of cross, is in positive correlation with high MPH for grain yield in maize. The cluster analysis based on MPH was not in accordance with the single sequence repeat (SSR) analysis of parental populations. Since both of the populations have some undesirable agronomic traits (high moisture, root and stalk lodging, bareness), two to three cycles of intrapopulation selection for improving them before starting the RRS program should be performed. In some additional grain quality research, these populations showed favorable value-added traits (high tryptophan, oil, and saturated fatty acids), indicating the possibility of improving grain quality besides grain yield in this newly discovered heterotic pattern.