Micromateorological and time-lapsed photography techniques in evaluating the effects of high temperature stress in rice
2019
Manigbas, N.L. | Madrid, L.B.
High temperature stress is one of the major constraints in rice production due to effects of global warming. One hour exposure of rice plants to 35 deg C temperature during flowering and grain-filling is enough to affect yield and grain quality. Rice yield can be reduced to 15% due to high temperature during flowering stage. Grain weight is decreased while chalky grains are increased as a result of heat stress during grain-filling. To assess the manifestation of high temperature stress and its effects to important agronomic traits, there is a need to evaluate the microclimate of rice plants under field condition. Three genotypes IR64, N22, and IR52 were planted in 2017 and 2018 dry season under non-stress and stress field conditions. Results showed that above canopy temperature (2m) was higher compared to within canopy. However, relative humidity was higher within canopy. Panicle temperature was higher within canopy during flowering and grain-filling. The number of spikelets increased under stressed condition between 76.2-89%, while spikelet fertility decreased between 63.9-89.2%. Weight of 1000 grain decreased between 29.5-72.4% while grain yield was reduced by 10.8-67%. Chalkiness increased between 29.5-72.4%. High percent sterility of 50% was observed in susceptible check IR52 compared to tolerant check N22 with 17%. Breeding is done to incorporate N22 high temperature tolerance trait to popular varieties for climate smart rice in the future.
显示更多 [+] 显示较少 [-]