Inheritance of ear yield and its components in sweet corn (Zea mays L. saccharat)

Abstract

Sweet corn is mutation of field corn in which greater accumulation of sugars and water soluble polysaccharides provide specific taste and texture. It is consumed in the milky stage of the endosperm, so the product's quality and its appearance are important as well as ear yield. That is why breeders pay the same attention to these traits in breeding process. In this paper we analyzed combining ability and mode of inheritance of ear yield and yield components in sweet corn, such as kernel-row number, and ear length, by the use of diallel crosses of six sweet corn inbred lines. ANOVA showed that estimates of general (GCA) and specific (SCA) combining abilities were highly significant (p lt 0.01) for all observed traits. Nonaditive gene effects were more significant in the expression of ear yield and ear length, while additive gene effects were more important for kernel-row number. Analysis of components of genetic variance was in agreement with the results of ANOVA of combining ability. The mode of inheritance of kernel-row number was partial dominance, while overdominance was of greater importance for ear yield, and ear length. Inbred line L4 was indicted as the most desirable, among the examined set of inbreds, in the further sweet corn breeding programs, due to its significant GCA effects concerning ear yield and number of kernels per ear, and ear yield performances of the hybrids in which one of the components was this inbred, according to SCA and hetrosis estimates.

Kukuruz šećerac predstavlja mutaciju kukuruza standardnog kvaliteta zrna, kod koga dolazi do povećanog nakupljanja šećera i u vodi rastvorljivih polisaharda, što njegovom zrnu obezbeđuje specifičan ukus i teksturu. S obzirom da se koristi u mlečnoj fazi razvoja endosperma, kvalitet i izgled klipa i zrna kukuruza šećerca podjednako su važni kao i sam prinos. U ovom radu proučavane su kombinacione sposobnosti šest samooplodnih linija kukuruza šećerca i način nasleđivanja prinosa klipa i komponenti prinosa, kao što su broj redova zrna i dužina klipa, metodom dialelne analize. Ananliza varijanse kombinacionih sposobnosti je pokazala visoko značajne vrednosti (p lt 0.01) opštih (GCA) i posebnih (PCA) kombinacionih sposobnosti za sve posmatrane osobine. Neaditivno delovanje gena bilo je značajnije za osobine prinos klipa i dužinu klipa, dok je aditivno delovanje gena bilo odlučujuće za ekspresiju broja redova zrna. Analiza komponenti genetičke varijanse bila je u saglasnosti sa razultatima ANOVA-e kombinacionih spososbnosti. Način nasleđivanja broja redova zrna bila je parcijalna dominacija, dok je za prinos klipa i dužinu klipa to bila superdominacija. Samooplodna linija L4 je posmatrajući vrednosti OKS za prinos klipa i broj redova zrna, kao i vrednosti PKS hibridnih kombinacija čija je bila komponenta, ocenjena kao najperspektivnija u daljem procesu oplemenjivanja kukuruza šećerca.