Effect of major genes (Rht-B1, Ppd-A1 and Vrn-A1) and loci identified by association mapping on yield and morfo-phenological traits in durum wheat

PABLO FEDERICO RONCALLO; ADELINA OLGA LARSEN; ANA LAURA ACHILLI; KARIM AMMAR; JULIO HUERTA ESPINO; ANNA MARIA MASTRANGELO; DANIELA MARONE; LISARDO GONZÁLEZ; PABLO CAMPOS; SUSANNE DREISIGACKER; MARIANO BEKER; VIVIANA ECHENIQUE

Bologna

Conferencia; FROM SEED TO PASTA IV-A Sustainable Durum Wheat Chain for Food Security and Healthy Lives; 2022

Universita di Bologna, CREA, CIMMYT, Wheat Initiative, Crop Development Centre-USASK

Grain yield is affected by genes involved in photoperiod sensitivity (Ppd), vernalization (Vrn) and plant height (Rht). However, additional unknown genes also affect wheat grain yield and morpho-phenological traits. The objective of this study was to contribute to decipher the genetic bases of the mentioned traits in durum wheat and its contribution to explain grain yield. A collection of 197 durum wheat genotypes was evaluated under field conditions in Argentina, Mexico and Italy for grain yield, plant height, peduncle length, heading date and flowering time. Also, the alleles at Rht-B1, Ppd-A1 and Vrn-A1 genes were assessed in the collection using SNP (KASPTM) and STS markers. The effect of the Ppd-A1/Vrn-A1 alleles combination on shortening of heading date was classified as Ppd-A1a (GS-100)/Vrn-A1c > Ppd-A1a (GS-105)/Vrn-A1c > Ppd-A1b/Vrn-A1c/a> Ppd-A1b/Vrn-A1b across 15 trials. The GS105 allele at Ppd-A1 was associated with increases in grain yield (five environments). The Rht-B1 gene showed a strong effect on plant height and peduncle length, as did loci detected by marker-trait associations (MTA) on 4A, 6A, 7B and 2B chromosomes. For grain yield, MTA were detected on 4A, 7B, 5A, 6B, 3B and 7B. In addition, loci significantly associated with heading date were observed on 5A, 2B, 1A, 3A and 3B. The SNP AX-94494720 on 4AL was significantly associated with plant height (five environments) and also with grain yield (three environments). The effect of Vrn-A1b delaying the date of heading was observed under different environmental conditions. Further exploitation of new loci for morpho-phenological traits could contribute to grain yield improvement.