Huang Min, Zhang Ruichun, Jiang Peng, Xie Xiaobing, Zhou Xuefeng, Cao Fangbo, Zou Yingbin
Southern Regional Collaborative Innovation Center for Grain and Oil Crops (CICGO), Hunan Agricultural University, Changsha, China.
Hengyang Institute of Agricultural Sciences, Henyang, China.
PLoS One. 2016 Jul 1;11(7):e0158601. doi: 10.1371/journal.pone.0158601. eCollection 2016.
Warm temperature during post-heading is generally hypothesized to be the critical factor limiting grain yield of early-rice in South China. However, there is no direct evidence to confirm this hypothesis in the field. This study was conducted to determine the temperature-related yield constraints of early-rice in South China. Field experiments were carried out in Huaiji (a location in South China) and Changsha (a location in the Yangtze River basin) in 2011-2013. In each year, two rice cultivars were grown in early-rice growing season in Huaiji and in single-rice growing season in Changsha. Huaiji had higher average daily maximum temperature during post-heading than Changsha. The higher temperature during post-heading induced early plant senescence (slower crop growth rate and shorter grain filling duration), but grain weight did not reduce because it was compensated for by increased translocation of pre-heading biomass. The higher temperature during post-heading also did not cause a reduction in grain filling percentage. Huaiji had lower temperature during pre-heading than Changsha, which to some extent resulted in slower crop growth rate and consequently lower biomass production and smaller sink size in Huaiji than in Changsha. As a result, grain yield was about 30% lower in Huaiji than in Changsha. Our results indicate that grain yield of early-rice in South China is limited not by warm temperature during post-heading but partially by cool temperature during pre-heading, and suggest that enhancing sink size and meanwhile maintaining good translocation of pre-heading biomass may be an effective way to achieve high yield for early-rice in South China.
一般认为，抽穗后温暖的温度是限制中国南方早稻产量的关键因素。然而，在田间尚无直接证据证实这一假设。本研究旨在确定中国南方早稻与温度相关的产量限制因素。2011 - 2013年在怀集（中国南方的一个地点）和长沙（长江流域的一个地点）进行了田间试验。每年，在怀集的早稻生长季节和长沙的单季稻生长季节种植两个水稻品种。怀集抽穗后的日最高平均温度高于长沙。抽穗后较高的温度导致植株早衰（作物生长速率减慢，灌浆持续时间缩短），但粒重并未降低，因为抽穗前生物量转运增加起到了补偿作用。抽穗后较高的温度也未导致灌浆率降低。怀集抽穗前的温度低于长沙，这在一定程度上导致作物生长速率较慢，进而怀集的生物量产量和库容量比长沙小。结果，怀集的水稻产量比长沙低约30%。我们的结果表明，中国南方早稻的产量并非受抽穗后温暖温度的限制，而是部分受抽穗前凉爽温度的限制，并表明增加库容量同时保持抽穗前生物量的良好转运可能是实现中国南方早稻高产的有效途径。
