TY - JOUR
T1 - Abscisic acid and the key enzymes and genes in sucrose-to-starch conversion in rice spikelets in response to soil drying during grain filling
AU - Wang, Zhiqin
AU - Xu, Yunji
AU - Chen, Tingting
AU - Zhang, Hao
AU - Yang, Jianchang
AU - ZHANG, Jianhua
N1 - This work was supported by grants from the National Basic Research Program (973 Program, 2012CB114306), the National Natural Science Foundation of China (31461143015; 31271641, 91317307; 31471438), the National Key Technology Support Program of China (2011BAD16B14; 2012BAD04B08;
2014AA10A605), the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), and Shenzhen Overseas Talents Innovation & Entrepreneurship Funding Scheme (The Peacock Scheme).
PY - 2015/5/1
Y1 - 2015/5/1
N2 - Main conclusion: Abscisic acid mediates the effect of post-anthesis soil drying on grain filling through regulating the activities of key enzymes and expressions of genes involved in sucrose-to-starch conversion in rice spikelets. This study investigated if abscisic acid (ABA) would mediate the effect of post-anthesis soil drying on grain filling through regulating the key enzymes in sucrose-to-starch conversion in rice (Oryza sativa L.) spikelets. Two rice cultivars were field-grown. Three treatments, well-watered (WW), moderate soil drying (MD), and severe soil drying (SD), were imposed from 6 days after full heading until maturity. When compared with those under the WW, grain filling rate, grain weight, and sink activity, in terms of the activities and gene expression levels of sucrose synthase, ADP glucose pyrophosphorylase, starch synthase, and starch branching enzyme, in inferior spikelets were substantially increased under the MD, whereas they were markedly decreased in both superior and inferior spikelets under the SD. The two cultivars showed the same tendencies. Both MD and SD increased ABA content and expression levels of its biosynthesis genes in spikelets, with more increase under the SD than the MD. ABA content was significantly correlated with grain filling rate and sink activities under both WW and MD, while the correlations were not significant under the SD. Application of a low concentration ABA to WW plants imitated the results under the MD, and applying with a high concentration ABA showed the effect of the SD. The results suggest that ABA plays a vital role in grain filling through regulating sink activity and functions in a dose-dependent manner. An elevated ABA level under the MD enhances, whereas a too high level of ABA under the SD decreases, sink activity.
AB - Main conclusion: Abscisic acid mediates the effect of post-anthesis soil drying on grain filling through regulating the activities of key enzymes and expressions of genes involved in sucrose-to-starch conversion in rice spikelets. This study investigated if abscisic acid (ABA) would mediate the effect of post-anthesis soil drying on grain filling through regulating the key enzymes in sucrose-to-starch conversion in rice (Oryza sativa L.) spikelets. Two rice cultivars were field-grown. Three treatments, well-watered (WW), moderate soil drying (MD), and severe soil drying (SD), were imposed from 6 days after full heading until maturity. When compared with those under the WW, grain filling rate, grain weight, and sink activity, in terms of the activities and gene expression levels of sucrose synthase, ADP glucose pyrophosphorylase, starch synthase, and starch branching enzyme, in inferior spikelets were substantially increased under the MD, whereas they were markedly decreased in both superior and inferior spikelets under the SD. The two cultivars showed the same tendencies. Both MD and SD increased ABA content and expression levels of its biosynthesis genes in spikelets, with more increase under the SD than the MD. ABA content was significantly correlated with grain filling rate and sink activities under both WW and MD, while the correlations were not significant under the SD. Application of a low concentration ABA to WW plants imitated the results under the MD, and applying with a high concentration ABA showed the effect of the SD. The results suggest that ABA plays a vital role in grain filling through regulating sink activity and functions in a dose-dependent manner. An elevated ABA level under the MD enhances, whereas a too high level of ABA under the SD decreases, sink activity.
KW - Inferior spikelets
KW - Oryza (rice)
KW - Sink activity
KW - Starch biosynthesis
KW - Superior spikelets
UR - http://www.scopus.com/inward/record.url?scp=84940005955&partnerID=8YFLogxK
U2 - 10.1007/s00425-015-2245-0
DO - 10.1007/s00425-015-2245-0
M3 - Journal article
C2 - 25589060
AN - SCOPUS:84940005955
SN - 0032-0935
VL - 241
SP - 1091
EP - 1107
JO - Planta
JF - Planta
IS - 5
ER -