%0 Journal Article
%T Effects of free-air CO2 enrichment on heat-induced sterility and pollination in rice
%A Hidemitsu Sakai
%A Hirofumi Nakamura
%A Kazuhiro Kobayasi
%A Mayumi Yoshimoto
%A Mohammad Jawid Eydi
%A Takeshi Tokida
%A Toshihiro Hasegawa
%A Yasuhiro Usui
%J Plant Production Science
%D 2019
%R https://doi.org/10.1080/1343943X.2018.1563496
%X ABSTRACT Global climate changes may cause heat-induced sterility in rice, threatening the global production of this important crop. Although little is currently known about the combined effects of the concentration of atmospheric CO2 ([CO2]) and temperature on heat-induced sterility, elevated [CO2] (E-[CO2]) will likely increase the panicle temperature and thereby exacerbate heat-induced sterility, but this was not tested in open fields. Therefore, we investigated the effect of E-[CO2] on heat-induced sterility and sterility-related traits in rice by increasing E-[CO2] by approximately 200£¿¦̀mol£¿mol£¿1 above ambient levels using a free-air CO2 enrichment (FACE) facility for six growing seasons with variable growing season temperatures. The percentage fertility was not significantly correlated with the air temperature (Ta) between 09:00 and 12:00 on each flowering day, but it did significantly vary among the years, with 2011 experiencing cool temperatures resulting in chilling-induced mild sterility. When data from 2011 were removed, there was a significant negative correlation between fertility and Ta between 09:00 and 12:00 on each flowering day under E-[CO2], whereas no such effect was seen under ambient [CO2]. E-[CO2] also significantly reduced the number of pollen grains deposited on the stigma by 10%, but it slightly increased the anther length by 1.3%, indicating that it had both negative and positive effects on heat-induced sterility. These findings suggest that E-[CO2] affects many traits related to heat-induced sterility and may sometimes exacerbate sterility by reducing pollen grain deposition. Abbreviations: A-[CO2]: ambient CO2; [CO2]: the concentration of carbon dioxide; E-[CO2]: elevated [CO2]; FACE: free-air CO2 enrichment; Ta: air temperatur
%U https://www.tandfonline.com/doi/full/10.1080/1343943X.2018.1563496