[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.
College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Yuchun
Y
Guo
Wenxiong
W
Lin
Qiumei
Q
Shi
Yiyuan
Y
Liang
Huaqin
H
He
Fangyu
F
Chen
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