Expected genetic advance for thousand grain weight and grain number per spike of bread wheat and durum wheat

Abstract

The research was aimed at examining variability, variance components, broad-sense heritability (h2), expected genetic advance of thousand grain weight (TGW) and grain number per spike (GNS) of 15 genotypes of bread wheat and 15 genotypes of durum wheat. Field trials were carried out during 2010-2011 and 2011-2012 growing seasons at the three sites: Rimski Šančevi, Zemun Polje and Padinska Skela. Results of this investigation showed that the genetic component of variance (σ2g) was predominant for TGW of bread and durum wheat and for GNS of bread wheat. The genotype × environment interaction (σ2ge) component of phenotypic variance was 8.72 times higher than σ2g for GNS of durum wheat and pointed to the greater instability of durum wheat genotypes. h2 was very high (>90%) for TGW and GNS of bread wheat, high for TGW of durum wheat - 87.3% and low for GNS of durum wheat - 39.5%. Considering the high values obtained for h2 - 96.4% and the highest value for expected genetic advance as percent of mean (GAM) - 19.3% for TGW of bread wheat, the success of selection for desired values of this yield component can be anticipated. The success of selection cannot be predicted for GNS of durum wheat due to low values obtained for h2 and GAM of 39.5% and 2.8%, respectively.

Ciljevi ovog istraživanja su bili da se prouči varijabilnost, komponente varijanse, heritabilnost u širem smislu (h2) i očekivana genetička dobit mase hiljadu zrna (MHZ) i broja zrna po klasu (BZK) za 15 genotipova hlebne pšenice i 15 genotipova durum pšenice. Poljski ogledi su izvedeni tokom 2010-2011. i 2011-2012. godine na tri lokaliteta: Rimski Šančevi, Zemun Polje i Padinska Skela. Rezultati istraživanja su pokazali da je genetička komponenta varijanse (σ2g) bila dominantna u fenotipskoj ekspresiji MHZ hlebne i durum pšenice i BZK hlebne pšenice. Komponenta fenotipske varijanse usled interakcije genotip × sredina (σ2ge) je bila 8,72 puta veća od σ2g za BZK durum pšenice i ukazala je na veću nestabilnost genotipova durum pšenice za tu osobinu. Koeficijent heritabilnosti je bio veoma visok (> 90%) za MHZ i BZK hlebne pšenice, visok za MHZ durum pšenice - 87,3% i nizak za BZK durum pšenice - 39,5%. Uzimajući u obzir visoke ostvarene vrednosti za h2 - 96,4% i za očekivanu genetičku dobit izraženu u procentima od proseka (GAM) - 19,3% za MHZ hlebne pšenice, moguće je predvideti uspeh selekcije pri oplemenjivanju navedene komponente prinosa. Uspeh selekcije se ne može predvideti za BZK durum pšenice zbog dobijenih niskih vrednosti za h2 i GAM od 39,5% odnosno 2,8%.