不同N-P源处理对菌根化高粱N和P吸收的影响

Effects of different N-P source treatments on N and P uptake of mycorrhizal sorghum

为了探究不同N-P源处理下,丛枝菌根(arbuscular mycorrhizal,AM)真菌对高粱N和P吸收的影响.应用凯氏定氮法测定总N含量,钥锑抗显色法测定总P含量,甲萘酚-双乙酰法测定精氨酸含量,Real-time PCR法检测菌根中的精氨酸分解酶GiCAR1的相对表达量,评价不同处理下高粱的N,P吸收差异.结果表明:尿素为N源时,地上部总N、总P含量达到最高,菌根中精氨酸酶GiCAR1表达水平最高,达到1.7569;在精氨酸为N源时,精氨酸酶表达水平最低(为1),低于对照组;尿素+过磷酸钙组,菌根精氨酸分解酶表达水平最高,达到15.9101,菌根组相对于非菌根组基因表达量高出9.13倍.综上所述,AM真菌吸收同化尿素的能力较强;AM真菌侵染能促进真菌与植株的能源转换,增加适量的过磷酸钙也会促进AM真菌对N源的吸收和利用,促进精氨酸的转运,从而增强了精氨酸分解酶基因的表达.

In order to study the effects of AM fungi on the absorption of N and P in sorghum under different N-P source treatments,the kjeldahl method was used to determine total nitrogen content,the molybdenum antimony anti-color method was used to determine total phosphorus content,the naphthol-diacetyl method was used to determine arginine content,real-time PCR method was used to detect the relative expression of arginase GiCAR1 in mycorrhiza,and the difference in N and P absorption of sorghum under different treatments were evaluated.The results showed that when urea was the N source,the total nitrogen and total phosphorus content in the shoots reached the highest,and the expression level of arginase GiCAR1 in mycorrhiza reached the highest 1.7569.When arginine was the N source,the lowest arginase expression level was 1,which was lower than the control group.In the urea+superphosphate group,the expression level of arginase reached 15.9101,and the gene expression level of the mycorrhizal group was 9.13 times higher than that of the nonmycorrhizal group.Experimental results showed that AM fungus had a strong ability to absorb and assimilate u-rea.AM fungal infection could promote energy conversion between fungi and plants.Increasing an appropriate amount of superphosphate could also promote the absorption and utilization of N sources by AM fungi,promote the transport of arginine,and enhance the expression of arginine decomposing enzyme genes.