[Effects of nighttime temperature increase at different growth stages on double season rice grain yield].
Two experimental glass-houses were utilized to study the effects of nighttime temperature increase (NTI) at different growth stages on the grain yield of double season rice. The NTI from the stage of sowing to panicle differentiation (primary branch differentiation) improved the tillering of rice, and increased the effective panicles. An average 1 degrees C rise in the minimum nighttime temperature (MNT) at this stage increased the grain yield of early and late rice by 10.02% - 13.18% and 6.52% - 7.78% (P < 0.01), respectively. The NTI from the stage of panicle differentiation to heading (10% panicle heading from flag leaf sheath) promoted the spikelet abortion, and reduced the number of developed spikelet. An average 1 degrees C rise in MNT at this stage decreased the grain yield of early and late rice by 3.76% - 6.67% and 3.66% - 6.94% (P < 0.01), respectively. NTI from the stage of heading to maturity decreased the filled grain rate of early rice remarkably, but had an opposite effect on late rice. An average 1 degrees C rise in MNT at this stage induced a grain yield loss by 2.07% - 5.61% (P < 0.05) and a grain yield gain by 1.63% - 2.28% (P < 0.05) for early and late rice, respectively. All the results illustrated that there existed obvious differences in the effects of NTI at different growth stages on the grain yield of double season rice.
Wei
Jin-Lian
JL
Ministry of Agriculture Key Laboratory of Physiology, Ecology and Cultivation of Double Cropping Rice, Jiangxi Agricultural University, Nanchang 330045, China. zydzyd2000@163.com
Pan
Xiao-Hua
XH
Deng
Qiang-Hui
QH
D018533:Biomass; D006358:Hot Temperature; D012275:Oryza / Q000145:classification / Q000254:growth & development*; D012639:Seeds / Q000254:growth & development*; D013997:Time Factors