title: Temperature-Related Yield Constraints of Early-Rice in South China: A Cross-Location Analysis.
abstract: 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.
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops (CICGO), Hunan Agricultural University, Changsha, China.
authors.forename: Min
authors.initials: M
authors.lastname: Huang
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops (CICGO), Hunan Agricultural University, Changsha, China.|Hengyang Institute of Agricultural Sciences, Henyang, China.
authors.forename: Ruichun
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops (CICGO), Hunan Agricultural University, Changsha, China.|Rice and Sorghum Research Institute, Sichuan Academy of Agricultural Sciences, Deyang, China.|Key Laboratory of Southwest Rice Biology and Genetic Breeding, Ministry of Agriculture, Deyang, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Jiang
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops (CICGO), Hunan Agricultural University, Changsha, China.
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Xie
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops (CICGO), Hunan Agricultural University, Changsha, China.
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops (CICGO), Hunan Agricultural University, Changsha, China.
authors.forename: Fangbo
authors.initials: F
authors.lastname: Cao
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops (CICGO), Hunan Agricultural University, Changsha, China.
authors.forename: Yingbin
authors.initials: Y
authors.lastname: Zou
mesh_terms: D002681:China; D012275:Oryza / Q000254:growth & development*; D012621:Seasons; D013696:Temperature; D013997:Time Factors