铝处理对不同耐铝水稻品种吸收铵态氮和硝态氮以及相关基因表达的影响

Effects of Aluminum Treatments on Uptake of Ammonium and Nitrate and Expression of Related Genes in Different Aluminum-tolerant Rice Varieties

选用水稻铝敏感品种‘Kasalath’和耐铝品种‘Koshihikari’为试验材料,研究了不同铝处理方式(先铝后氮和氮铝同时处理)对水稻铵态氮/硝态氮吸收及其相关基因表达的影响。结果表明:对于铝敏感品种,铝主要抑制铵态氮的吸收,低浓度铝甚至促进对硝态氮的吸收;对于耐铝品种,铝预处理对铵态氮和硝态氮吸收的影响很小,只有在铵态氮和硝态氮吸收过程中存在铝,无论铝浓度高低,铝都会抑制铵态氮和硝态氮吸收;铝敏感品种对硝态氮的吸收速率高,而耐铝品种对铵态氮的吸收速率高,这与OsAMT1;2、OsNRT2;1和OsNRT2;2的相对表达丰度存在对应关系。因此,铝对水稻铵态氮和硝态氮吸收的影响取决于水稻的耐铝能力、铝浓度和铝氮处理方式。

Two rice varieties‘Kasalath’(Al-sensitive)and‘Koshihikari’(Al-tolerant)were used to study the effects of different Al and N treatments(Al pretreatment followed by N treatment,Al and N treatment at the same time)on the uptake of NH4^(+)/NO3^(-)and related gene expression in rice.The results showed that for the Al-sensitive variety,Al mainly inhibited the uptake of ammonium,while a low concentration of Al even promoted the uptake of nitrate.For the Al-tolerant cultivar,the uptake of NH 4^(+)and NO 3^(-)was almost not affected by the pretreatment of Al.As long as Al was supplied together with NH4^(+)and NO3^(-),the uptake of NH4^(+)and NO3^(-)would be inhibited regardless of Al concentrations.Al-sensitive variety had a higher nitrate uptake rate,and Al-tolerant variety had a higher ammonium uptake rate.There is a corresponding relationship between the relative expression abundance of OsAMT1;2,OsNRT2;1 and OsNRT2;2 and the uptake rates of ammonium and nitrate.We concluded that the effects of Al on the uptake of ammonium and nitrate by rice depend on Al tolerance of rice,Al treatment concentrations and the treatment method of Al and N.