Application of three methods in water-saving wheat breeding

At present, water shortage seriously affects wheat production in many parts of the world, and to solve this problem, water-saving wheat breeding is an important research domain. The objective of this study was to evaluate water-saving index (WSI), yield factors, and KASP (kompetitive allele specific polymerase chain reaction) markers in water-saving wheat breeding carried out in Hengshui region, China. The result showed as follows: (1) The new index WSI could better indicate the water-saving performance, including the yield potential and the stability of different wheat cultivars under water limited condition (WL). (2) Referring to the degree of heat stress (D) in that year, selecting one of the three yield factors as the focus will improve the breeding efficiency of water-saving wheat cultivars. With the increase of the D within a certain range, high water-saving wheat cultivars showed a high grain weight (GW) under WL. Meanwhile with the decreasing of D value, high water-saving wheat cultivars showed high spike number under WL. (3) KASP aggregation breeding will significantly improve the efficiency of water-saving breeding. The combination with the highest effective rate of selecting water-saving varieties carried GS5-2334-SNP and Dreb_SNP favorable alleles, and GW2-6B-1709SNP, TaMoc-2433, and 1fehw with adverse alleles, whereas GS5-2334-SNP and GW2-6B-1709SNP that related to GW were useful markers for water-saving breeding. These results improved our knowledge on the usage of WSI, yield factors, and KASP markers on water-saving wheat breeding.