不同施氮量对甜椒碳、氮营养分配的影响

Effect of Different Nitrogen Applied on the Distribution of Carbon and Nitrogen in Sweet Pepper

通过水培试验,利用15N和13C双示踪技术研究了不同施氮量对甜椒结果期碳、氮营养分配的影响。结果表明:结果前期吸收的15N在低氮(NO3--N 2.5 mol·L-1,NH4+-N 0.25 mol·L-1)营养处理下分配于果实中的比率高于中氮(NO3--N 5.0 mol·L-1,NH4+-N 0.5 mol·L-1)和高氮(NO3--N 11.0 mol·L-1,NH4+-N 1.0 mol·L-1)营养处理。氮水平制约着15N在各器官中的分配和再运转,很少影响13C在器官间的分配,但却制约着13C的运转和再分配,表现为中氮营养最有利于13C向果实中的再运转。碳氮营养平衡有利于碳素向生殖器官的运转和积累,这是低氮营养产量前高后低,高氮营养产量前低后高,中氮营养前后期产量均较高的根本原因。

Sweet pepper (Capsicum annuum L. ) was used to study the effect of different nitrogen applied on the distribution of carbon and nitrogen assimilated and absorbed during fruit harvest period by using 15N and 13C double tracer technique. The results obtained are as follows; The distributed ratio of the 15N absorbed at early fruiting stage on the fruit was 50. 49% at lower N and it was higher significantly than that at the moderate and the higher N treatments. Nitrogen nutrition not only controlled the distribution of 15N absorbed on the different organs, but also affected its translocation. Nitrogen nutrition affected hardly the distribution of 13 C assimilated among the organs but controlled the translocation and redistribution of 13 C, and as a result, the moderate N was most beneficial to the redistribution of C up to fruit. The balance of carbon and nitrogen is favorable to the accumulation and translocation to the reproductive organ. It is why that the yield is higher earlier stage than after stage at lower N, but adversely at higher N and only at moderate N either of all is higher.