The Effects of Night-time Temperatures on Physiological and Biochemical Traits in Rice

Abstract

High nighttime temperatures impair rice yield. Additionally, heat stress periods have increased during the last years in the rice areas of the tropics. The aim of this study was to physiologically characterize six genotypes of rice (a commercial cultivar (ʻF60ʼ) and five selected lines (ʻIR 1561ʼ, ʻFLO 2764ʼ, ʻLV447-1ʼ, ʻCT19021ʼ, and ʻLV1401ʼ) subjected to two nighttime temperatures (24 and 30 °C), based on different physiological traits. When the collar formed on leaf 6 of the main stem, one group of six plants in each genotype was subjected to 30 °C from 18:00 to 24:00 hours for eight days, while the other group remained at 24 °C. Differences were found in the interaction between genotype and nighttime temperatures, where a high night temperature reduced leaf photosynthesis by approximately 50% in all genotypes compared to the controls (20 µmol vs. 10 µmol CO 2 m -2 s -1 , respectively). In general, higher plant respiration was also observed in almost all genotypes when the plants were exposed to 30 °C. However, rice plants of the genotype ʻF60ʼ showed a constant respiration under two different night temperatures. A high nighttime temperature increased the electrolyte leakage and malondialdehyde content only in the ʻLV1401ʼ plants. Plant growth and F v /F m ratio were separately conditioned by the night temperature or the genotype factor. A lower total plant dry weight was found at 30 °C (620.36 mg) than in rice plants exposed to 24 °C (254.16 mg). The F v /F m ratio was slightly diminished at a high nighttime temperature. These results suggest that physiological variables, such as leaf photosynthesis, plant respiration, malondialdehyde content and leaf photosynthetic pigments, can be considered markers for characterizing tolerant genotypes in earlier growth phases during plant breeding programs.

Systematic determination of the reproductive growth stage most sensitive to high night temperature stress in rice (Oryza sativa)

“…Reduced F V /F M indicates damage to PSII proteins, such as D1, or impairments of the repair system of PSII proteins (Gururani, Venkatesh, & Tran, 2015; Song, Yue, Zhao, & Hou, 2013). Reductions in F V /F M , due to HNT, align with previous studies of HNT and rice (Alvarado‐Sanabria, Garcés‐Varón, & Restrepo‐Díaz, 2017a, 2017b). In this study, we observed that even short periods of HNT (5.5 h of pre‐ or post‐midnight stress) can reduce F V /F M .…”

The influence of high night temperature on yield and physiological attributes of Soybean cv. Fukuyutaka

“…When NT increases, the excessive consumption of carbohydrates results in biomass decrease in corn (Hoeft et al, 2000). The increase in respiration rate also occurred in soybean and rice under HNT (Alvarado-Sanabria et al, 2017;Djanaguiraman et al, 2013;Mohammed & Tarpley, 2009). Although the results showed a negative correlation between respiration rate and HNT, its association with crop growth, yield components and physiological response in soybean under HNT has not been fully evidenced.…”

“…HNT tended to decrease yield (Figure 2(c)). The yield decline under HNT has been observed in chamber and field-level studies for rice (Alvarado-Sanabria et al, 2017;Mohammed & Tarpley, 2009Peng et al, 2004;Y. Zhang et al, 2013) and in a phytotron study of the combination of high daytime and night temperatures for soybean growth (Gibson & Mullen, 1996).…”

“…However, the response was inconsistent and unclear. The decrease in the photosynthesis rate occurred in soybean, sorghum, spring wheat, cotton and rice (Djanaguiraman et al, 2013;22C/28C;14C/23C;Prasad et al, 2008;20C/ 30C;Snider et al, 2009;24C/30C;Alvarado-Sanabria et al, 2017), but the photosynthesis rate increased in rice and Populus spp. (17C/27C, Kanno et al, 2009; 15C/25C; Turnbull et al, 2002), and no significant influence was found on the photosynthesis rate in rice (Mohammed & Tarpley, 2009).…”

Selection of sowing date and biofertilization as alternatives to improve the yield and profitability of the F68 rice variety

“…For this reason, in the SD of August, the highest yield and the LCB reached 25 μmol CO 2 / μmol CO 2 respiration; this, however, is explained by the lower nighttime temperature that occurred in this SD. The above is favorable for rice plants since this environmental condition decreases their respiration rate (Alvarado et al, 2017). Furthermore, this condition affects the availability of carbohydrates for grain filling, so the magnitude of respiration can increase or reduce yield (Peraudeau et al, 2015).…”