摘要
以磷高效水稻基因型连珍11和磷低效水稻基因型嘉948为材料,通过溶液培养试验研究了正常供磷(10 mg P?L-1)和低磷胁迫(0.5 mg P?L-1)条件下的根系形态,根系磷吸收动力学参数和根系分泌酸性磷酸酶特性.结果表明,在两种供磷条件下,连珍11的吸磷量均显著高于嘉948.与嘉948相比,连珍11具有较大的根干重,根长,根表面积和侧根数量.低磷胁迫下连珍11的根系磷吸收动力学参数Imax,Km和Cmin均显著低于嘉948;而在正常供磷条件下两个水稻基因型的Imax和Km没有显著差异.低磷处理显著增加两个水稻基因型的Imax,却显著降低Km.正常供磷条件下两个基因型根系分泌酸性磷酸酶活性没有显著差异,而在低磷处理条件下连珍11的根系分泌酸性磷酸酶活性显著高于嘉948.研究表明连珍11的磷效率显著高于嘉948的原因是其具有较庞大的根系以及在磷缺乏条件下具有较高的根系分泌酸性磷酸酶活性和较低的Km和Cmin值.
A hydroponic experiment supplied with either sufficient P （10 mg P·L^-1 ） or deficient P （0.5 mg P·L^-1 ） was conducted to study the root morphology, root P uptake kinetic parameters and root secreted acid phosphatase activity （APA） of Lianzhen 11 （P-efficient rice genotype） and Jia 948 （Pinefficient rice genotype）. Results indicated that Lianzhen 11 showed greater P uptake than Jia 948 at two different P levels. Compared with Jia 948, Lianzhen 11 had greater root dry weight, root length, root surface area and more lateral roots. Lianzhen 11 showed lower Imax, Km and Cmm than Jia 948 at deficient P treatment, whereas there was no significant difference in Imax or Km between Lianzhen 11 and Jia 948 at sufficient P treatment. Low P treatment significantly increased the Imax （P〈 0.05）, but significantly decreased the Km （P〈0.05） for both rice genotypes. Lianzhen 11 showed higher root secreted APA than Jia 948 at deficient P treatment; whereas there was no difference at sufficient P treatment. In conclusion, compared to genotype Jia 948, the higher P efficiency of Lianzhen 11 can be explained by the fact that Lianzhen 11 has a greater root syslem and maintains a higher root secreted APA and lower Km and Cmin under P-deficient conditions.
出处
《浙江大学学报（农业与生命科学版）》
CAS
CSCD
北大核心
2006年第6期658-664,共7页
Journal of Zhejiang University:Agriculture and Life Sciences
基金
国家自然科学基金资助项目(30471039)
