[Physiological adaptability of seeding rice genotypes with different P uptake efficiency under low P-deficient stress].
The genotypic differences in P uptake efficiency of three rice varieties (IR74, IR71331 and IR71379) were studied under the P-deficiency condition with hydroponics, and their adaptability to low phosphorus stress about physio-biochemical mechanisms was further studied. The results showed that rice genotypes tolerated low P stress resulted from the co-ordination of P uptake efficiency, internal utilization efficiency and its translocation efficiency. The higher P-efficiency type IR74 and the middle type IR71331 had a higher P uptake efficiency. The rice genotype with higher P-efficiency was characterized by higher activity and desirable kinetic parameters of H2 PO4- uptake, showing lower Km and Cmin, but higher Imax values and relative APase activity, small amount of Km and Cmin. Moreover, under low P stress, the activity of RNase was about ten to fifteen times as high as that of the control (CK), but it had little genotypic differences.
Guo
Yuchun
Y
College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Lin
Wenxiong
W
Shi
Qiumei
Q
Liang
Yiyuan
Y
He
Huaqin
H
Chen
Fangyu
F
D000135:Acid Phosphatase / Q000378:metabolism; D000222:Adaptation, Physiological / Q000187:drug effects / Q000235:genetics*; D001692:Biological Transport / Q000187:drug effects; D005838:Genotype; D007700:Kinetics; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism; D010758:Phosphorus / Q000172:deficiency / Q000378:metabolism / Q000494:pharmacology; D017553:Phosphorus Compounds / Q000378:metabolism* / Q000494:pharmacology; D012260:Ribonucleases / Q000378:metabolism
D010710:Phosphates; D017553:Phosphorus Compounds; D010758:Phosphorus; D012260:Ribonucleases; D000135:Acid Phosphatase