Responses of Cotton at Different Growth Stages to Aeration Stress under the Influence of High Temperature

Abstract

In the middle reach of the Yangtze River Plain, cotton (Gossypium hirsutum. L) can experience aeration stress at multiple growth stages, often accompanied by high temperature. These two stresses can negatively affect growth and yield. This study aimed to investigate the responses of cotton at different growth stages to aeration stress, particularly under high temperature. Two field experiments examining cotton responses to aeration stress were conducted over 8 yr, and structural equation modeling was performed to reveal the relationships among aeration stress, high temperature, and the growth and yield of cotton at four growth stages. The interannual variability in the yield‐reducing effect of aeration stress was closely associated with high temperature. Aeration stress and high temperature both interactively (in Experiment 1) and independently (in Experiment 2) reduced seed cotton yield. The interaction between these two stresses was observed only in Experiment 1, in which the impact of aeration stress was relatively slight. In Experiment 1, the growth stage most sensitive to aeration stress changed with high temperature. In both experiments, under high temperature, the sensitivity of seed cotton yield to aeration stress was threefold higher at the flowering and boll‐filling stage than at the other stages. In conclusion, the responses of cotton to aeration stress depend on the time at which aeration stress occurs and the additional impact, if any, of high temperature.

The Effects of Flood, Drought, and Flood Followed by Drought on Yield in Cotton

“…This conclusion was also confirmed by our results: the flood/droughtinduced yield losses increased with the duration of flood or drought (Figure 4a). In most flood stress research, the stress intensity was demarcated by different flood durations [13,26,27,35], which was also the case in the present work (Table 1). As a result, the yield-reducing effects of flood derived from different cotton experiments, including ours, are comparable, and the results are given in Figure 6.…”

“…In particular, the nonsynchronous responses of seed cotton yield and dry matter yield can be explained by the more sensitive response in cotton reproductive growth than in vegetative growth. In fact, the recovery of cotton vegetative growth after water stress has been discovered under both flood and drought conditions [13,45]. Moreover, the harvest index was not reduced by any water stress treatment (Table 3).…”

“…As most stresses negatively affect cotton growth, the combined effects of two stresses may be more harmful. For instance, the combined effect of waterlogging and heat stress [13], and that of waterlogging and low light were found positively significant [9], which means the combination of two stresses could induce more impairments on cotton than their additive effects. In comparison, our result regarding flood followed by drought stress showed that the combined effect of flood and drought was obviously less than their additive effects.…”

“…The cotton cultivar E'kang 9 was chosen because it is a commonly-used cultivar in the research area [13]. Cotton seeds were sown directly on the surface soil of every lysimeter on 25 May, and the cotton plants (including roots) were dug out and collected on 28 October.…”

“…At the end of The soil type of the lysimeter soils was classified as silty clay loam soil according to the US soil texture classification [36], with a saturated water content and a field capacity (FC) of 44.6% and 32.0% (in volumetric moisture content), respectively. In addition, each lysimeter was equipped with an automatically controlled water supply and drainage system (designed by Wuhan University, China, [13,37]) capable of regulating the water tables to designated levels.…”