Ppd1, Vrn1, ALMT1 and Rht genes and their effects on grain yield in lower rainfall environments in southern Australia

Abstract

Abstract. Allele-specific markers for important genes can improve the efficiency of plant breeding. Their value can be enhanced if effects of the alleles for important traits can be estimated in identifiable types of environment. Provided potential bias can be minimised, large, unbalanced, datasets from previous plant-breeding and agronomic research can be used. Reliable, allele-specific markers are now available for the phenology genes Ppd-D1, Vrn-A1, Vrn-B1 and Vrn-D1, the aluminium-tolerance gene TaALMT1, and the plant-stature genes Rht-B1 and Rht-D1. We used a set of 208 experiments with growing-season rainfall of <347 mm from southern Australia to estimate the effects of seven frequent combinations of the phenology genes, an intolerant and a tolerant allele of TaALMT1, and two semi-dwarf combinations Rht-B1b + Rht-D1a (Rht-ba) and Rht-B1a + Rht-D1b (Rht-ab) on grain yield in lower rainfall, Mediterranean-type environments in southern Australia. There were 775 lines in our analyses and a relationship matrix was used to minimise bias.Differences among the phenology genes were small, but the spring allele Vrn-B1a might be desirable. The tolerant allele, TaALMT1-V, was advantageous in locations with alkaline soils, possibly because of toxic levels of aluminium ions in subsoils. The advantage of TaALMT1-V is likely to be highest when mean maximum temperatures in spring are high. Rht-ab (Rht2 semi-dwarf) was also advantageous in environments with high mean maximum temperatures in spring, suggesting that for these stress environments, the combination of Vrn-B1a plus TaALMT1-V plus Rht-ab should be desirable. Many successful cultivars carry this combination.

Strategic crossing of biomass and harvest index—source and sink—achieves genetic gains in wheat

“…It can also make use of markers, though currently these are more likely to be for alleles associated with genes of major effect-such as Ppd, Vrn, and Rht in wheat (Eagles et al 2014). Nonetheless, since selecting among early generation progeny for expression of complex traits is not always feasible (due in part to very large numbers), it is expected that genomic selection-potentially in combination with high throughput phenotyping of few integrative traits like canopy temperature and vegetative indices (Rutkoski 2016)-will find valuable application in selection of early generations based on strategic crossing for complex physiological traits.…”

TaALMT1 and TaMATE1B allelic variability in a collection of Brazilian wheat and its association with root growth on acidic soil

“…In fact, the most productive wheat genotypes in acid soil and rainfed conditions at the São Paulo state in Brazil were also Al resistant (Camargo et al 2003). Besides that, the TaALMT1 promoter Type V was also shown to be advantageous in lower-rainfall regions of southern Australia, and it is likely to be most beneficial under high temperature when soil moisture is expected to be limiting (Eagles et al 2014). In this context, wheat cultivars recommended for rainfed conditions at the Brazilian Cerrado will benefit from the joint action of superior TaALMT1 and TaMATE1B alleles.…”

Identification of Earliness Per Se Flowering Time Locus in Spring Wheat through a Genome‐Wide Association Study

“…It can survive extreme temperatures through the vegetative (-35°C) to grain filling (40°C) phases and is grown under different climatic conditions from Australia to Canada (Reynolds et al, 2009;Kamran et al, 2013). Vernalization (VRN) and photoperiod (PPD) are the (very wellstudied) major gene systems that control flowering time in wheat (Yan et al, 2003;Li et al, 2011;Chen and Dubcovsky, 2012;;Zheng et al, 2013;Eagles et al, 2014;Guedira et al, 2014;Nishiura et al, 2014). Vernalization (VRN) and photoperiod (PPD) are the (very wellstudied) major gene systems that control flowering time in wheat (Yan et al, 2003;Li et al, 2011;Chen and Dubcovsky, 2012;;Zheng et al, 2013;Eagles et al, 2014;Guedira et al, 2014;Nishiura et al, 2014).…”