Abiotic Stress Response of Near-Isogenic Spring Durum Wheat Lines under Different Sowing Densities

Abstract

A detailed study was made of changes in the plant development, morphology, physiology and yield biology of near-isogenic lines of spring durum wheat sown in the field with different plant densities in two consecutive years (2013–2014). An analysis was made of the drought tolerance of isogenic lines selected for yield QTLs (QYld.idw-2B and QYld.idw-3B), and the presence of QTL effects was examined in spring sowings. Comparisons were made of the traits of the isogenic pairs QYld.idw-3B++ and QYld.idw-3B−− both within and between the pairs. Changes in the polyamine content, antioxidant enzyme activity, chlorophyll content of the flag leaf and the normalized difference vegetation index (NDVI) of the plot were monitored in response to drought stress, and the relationship between these components and the yield was analyzed. In the case of moderate stress, differences between the NIL++ and NIL−− pairs appeared in the early dough stage, indicating that the QYld.idw-3B++ QTL region was able to maintain photosynthetic activity for a longer period, resulting in greater grain number and grain weight at the end of the growing period. The chlorophyll content of the flag leaf in phenophases Z77 and Z83 was significantly correlated with the grain number and grain weight of the main spike. The grain yield was greatly influenced by the treatment, while the genotype had a significant effect on the thousand-kernel weight and on the grain number and grain weight of the main spike. When the lines were compared in the non-irrigated treatment, significantly more grains and significantly higher grain weight were observed in the main spike in NIL++ lines, confirming the theory that the higher yields of the QYld.idw-3B++ lines when sown in spring and exposed to drought stress could be attributed to the positive effect of the “Kofa” QTL on chromosome 3B.

CO2 Responses of Winter Wheat, Barley and Oat Cultivars under Optimum and Limited Irrigation

“…Especially in the case of wheat, the effects of water shortage depend on onset time, duration and intensity. Aside from the developmental stages and the severity of the stress, the effects of water shortage on cereals depend on soil type, environmental conditions [30,31], the cultivated varieties or species [32,33] and also the cultivation technologies employed [34,35]. Drought can cut wheat yields by up to 92% [27], but sometimes extreme drought at the right time can lead to a total yield loss.…”

Changes in Antioxidant Defence System in Durum Wheat under Hyperosmotic Stress: A Concise Overview

“…Due to the multiplicity of factors influencing field experiments, these studies provided, in some cases, contrasting results with each other and compared to controlled-environment studies. In this regard, Bányai et al [ 45 ] evaluated the antioxidant response under rain-fed and well-watered conditions in the flag leaf at the flowering stage of eight near-isogenic lines of spring durum wheat, selected for yield QTLs. Authors reported a significant increase (on average) of POX activity in the non-irrigated treatment compared to irrigated plots, while a decrease of APX activity was observed, resulting of a similar order of magnitude for all the isogenic lines (averaging about 70%) [ 45 ].…”

“…In this regard, Bányai et al [ 45 ] evaluated the antioxidant response under rain-fed and well-watered conditions in the flag leaf at the flowering stage of eight near-isogenic lines of spring durum wheat, selected for yield QTLs. Authors reported a significant increase (on average) of POX activity in the non-irrigated treatment compared to irrigated plots, while a decrease of APX activity was observed, resulting of a similar order of magnitude for all the isogenic lines (averaging about 70%) [ 45 ]. Interestingly, APX activity was in significant positive correlation with the number of spikelets on the main spike ( r = 0.803***), and POX activity with the number of sterile basal spikelets ( r = 0.847***) [ 45 ].…”

Association analysis for agronomic traits in wheat under terminal heat stress

“…Quantitative trait loci (QTLs) are the nucleotides sequence on the genome controlling the trait of interest. It requires the progenies/population developed from crosses between desirable parents which includes RILs (recombinant inbred lines), backcross progenies, F 2 population, double haploid and near isogenic lines ( Kim et al, 2021a , Kim et al, 2021b , Bányai et al, 2021 ). QTL mapping have advantages viz., rare allele identification, few genetic markers requirement and no population structure effects.…”

“…QTL mapping have advantages viz., rare allele identification, few genetic markers requirement and no population structure effects. Whereas, disadvantages includes long period to develop populations, costly, laborious, limited detection of QTLs and few events of recombination consequently coarse mapping ( Kim et al, 2021a , Kim et al, 2021b , Bányai et al, 2021 ).…”