氮钾营养与花椰菜氮素代谢和产量的初步研究

采用４种不同氮钾营养处理研究了花椰菜叶片硝酸盐的还原作用，硝酸还原酶活性与花球产量的关系，结果表明，以Ｎ８Ｋ１０处理植株生物较好，花球产量与单位叶面积商品生产率最高，Ｎ８Ｋ５，Ｎ１５Ｋ１０和Ｎ１０Ｋ５处理依次降低，植株不同叶位叶片的ＮＲ活性自下而上逐渐提高。氮钾交互作用明显地影响叶和ＮＲ活性和ＮＯ３＾－—Ｎ含量。增氮显著地提高ＮＲ活性，降低ＮＯ３＾－—Ｎ含量，低氮时增钾提高ＮＲ活性，降低ＮＯ３＾－

THE PRELIMINARY STUDY ON THE RELATIONSHIPBETWEEN NK NUTRITION AND NITROGEN METABOLISM,CURD YIELD IN CAULIFLOWER(Brassica Oleracea var.botrytis L.)

The effects of four NK treatments on nitrate reductase(NR)activity ,nitrate ni-trogen(NO3-N)content of leaves and curd yield in cauliflower were studied.The results in-dicated that N8K10 treatment resulted in better plant growth ,the highest curd yield and perunit leaf area curd productivity as compared with the other treatments which decreased inthe order of N8K5,N16K10,N16K5.The NR activity in leaves was higher during the curd for-mation ,while lower before flower bud differentiation and at curd harvest.The NR activityin leaves increased gradually form low to high nodes.The change trends of NO3-N contentof leaves were the same as the NR activity NK interaction caused marked effects on NR ac-tivity and NO3-N content of leaves.High N treatment could promote NR activity and de-crease NO3-N content.When N level was lowet , high K treatment could enhance NR ac-tivity and decrease NO3-N content.When N level was higher,high K treatment could de-crease NR activity and increase NO3-N content. There were no significant correlation be-tween NR activity in leaves of various growth period and curd yield.