Heat stress response of wheat cultivars with different ecological adaptation

Abstract

In the present study, heat treatment was carried out in five different phenological phases, from the first node detectable (DEV31) growth stage to 20 days after flowering, on four wheat genotypes with very different adaptation strategies. They were grown in a controlled environment in a phytotron chamber and exposed to a night temperature of 20ºC and a day temperature of either 30ºC, at DEV31, or 35ºC at all the later developmental phases, for an interval of 14 days. Plant height, leaf number, number of tillers, grain number and grain weight per main and side spikes, TKW per main and side spikes, length of the main and side spikes, and spikelet number per main and side spikes were recorded. High temperature enhanced the stem growth intensity, plant height and tiller number. In contrast, the length of side spikes, spikelet no./side spike, grain no./main and side spike, grain weight/main and side spike and TKW/main and side spike were significantly decreased. The stress response depended strongly on the developmental phase in which the heat stress was applied. Fleischmann 481 and Soissons showed definitely contrasting tendencies both in grain number and grain weight. In the case of the Plainsman V and Mv Magma pair, the higher heat stress tolerance of Magma compared to Plainsman V was evident also from the grain number and weight of the main spike at each developmental phase.

The effects of brief heat during early booting on reproductive, developmental and physiological performance in common wheat (Triticum aestivum L.)

“…The number of spikes per plant, interacting with spikelet number and floret fertility, determines grain number and thereby final yield. Our data show that a short episode of heat stress during early booting stage induced the development of new tillers and spikes, which is in agreement with other studies (Bányai et al 2014; Hütsch, Jahn & Schubert 2019; Chavan, Duursma, Tausz & Ghannoum 2019). Though under severe heat stress tillering was initially inhibited, new tillers started emerging at two weeks after recovery, corresponding to about one week after anthesis.…”

“…In contrast, after a short episode of heat stress during earlier developmental stages, spike numbers increased (Bányai et al 2014;Hütsch et al 2019;Chavan et al 2019). Enhanced spike formation after early heat stress is surprising, but the underlying tillering dynamics and impact on final yield have not been dissected.…”

“…When exposed to continuous high temperatures during the terminal flowering and grain filling stages, spike formation and tillering were always reduced (Cai et al 2016; Sharma et al 2016; Dwivedi et al 2017; Kumar et al 2021). In contrast, after a short episode of heat stress during earlier developmental stages, spike numbers increased (Bányai et al 2014; Hütsch et al 2019; Chavan et al 2019). Enhanced spike formation after early heat stress is surprising, but the underlying tillering dynamics and impact on final yield have not been dissected.…”

Elevated CO2 alleviates the negative impact of heat stress on wheat physiology but not on grain yield

“…As discussed earlier, HS caused irreversible photosynthetic damage at aCO 2 , while growth at eCO 2 mitigated the negative impact of HS on photosynthesis. Moreover, the biomass of HS plants recovered under both CO 2 treatments due to late tiller and ear development (Bányai et al , 2014). When grain development is stalled under certain conditions (e.g.…”

Decimal growth stages for precision wheat production in changing environments?

“…The yields of wheat crops are at risk of abiotic stresses throughout plant development, until physiological maturity. Varieties can vary in their tolerance of stresses applied for ranges of DGS (Bányai et al , ). It is evident that some growth stages are particularly sensitive to the environment (Craufurd et al , ).…”