Effects of elevated air temperature on physiological characteristics of flag leaves and grain yield in rice

Abstract

1As an indispensable environment element for crop growth, air temperature has brought challenge for the sustainable development of rice (Oryza sativa L.) production. Elevated air temperature led to great loss in rice grain yield in many districts suffering from heat stress due to the greenhouse effect worldwide, which has received more and more attention from researchers. A field experiment was conducted to investigate impacts of high air temperature (HAT) after rice heading stage on dynamics of SPAD values, soluble sugar, soluble protein, and malondialdehyde (MDA) contents of flag leaves, and grain yield attributes. The results showed that HAT significantly reduced SPAD values, soluble sugar and protein contents, seed-setting rate, number of filled grains per panicles, 1000-grain weight, and grain yield, while increased MDA content. There exists strong correlation between each physiological parameter and days from heading stage to maturity, which can be simulated by quadratic curve equation or linear regression equation. Under HAT, the enhanced MDA content and decreased soluble sugar content demonstrated the damage of membrane structure and photosynthesis function of rice flag leaves, which was partially attributed to the reduced SPAD value and soluble protein content. In the present experiment, rice seed-setting rate was more vulnerable to HAT than grain weight. The disturbance of physiological metabolism in flag leaves was a fundamental reason for the reduction of rice grain yield under HAT.

Biochemical and physiological characterization of three rice cultivars under different daytime temperature conditions

“…The MDA concentration was higher in 'F60' plants at 40 °C, as was the percentage of electrolyte leakage, indicating greater cell membrane damage. Similar results were observed in rice plants by Zhang et al (2009) and Liu et al (2013), who also reported that the highest values of MDA occurred in the leaves of rice cultivars with enhanced susceptibility to heat stress.…”

“…Challenging temperature conditions of 37 °C/30 °C (day/ night) increase the electrolyte leakage percentage and MDA content in rice (Zhang et al, 2009). Similar results were also obtained by Liu et al (2013) in rice plants.…”

Pre-Field Screening Protocols for Heat-Tolerant Mutants in Rice

“…A change in concentration of MDA is a good indicator of membrane structural integrity under temperature stress (Sanchez-Reinoso et al 2014). Increase temperature stress 37 C/30 C (day/night) increased MDA content and electro leakage percentage in rice (Zhang et al 2009;Liu et al 2013).…”

Translocation efficiencies and allocation of nitrogen, phosphorous and potassium in rice as affected by silicon fertilizer under high daytime temperature

“…It has been established that rice is most sensitive to high temperature stress during reproductive stage, that is, from panicle initiation to grain‐filling stage (Jagadish, Craufurd, & Wheeler, ; Jagadish et al., ; Prasad, Boote, Allen, Sheehy, & Thomas, ). High temperature during reproduction stage induces decreased soluble sugar and protein, chlorophyll content and photosynthetic production in rice leaves (Liu, Wu, Li, Ma, & Zhou, ). These physiological changes inevitably result in insufficient assimilates supply from leaves and stems to grains, retarding the normal growth of grain and eventually reducing grain weight (Kobata & Uemuki, ; Shi et al., ).…”