【摘要】 以沈阳草甸土为栽培基质 ,采用二次D 饱和最优设计 ,进行番茄N、Ca两因素效应的盆栽试验 .结果表明 ,在本试验条件下 ,番茄茎、叶、果实中氮素含量随生育期的进展而下降 ,氮肥对番茄果实中NO-3 N含量影响呈直线正效应 ,但各处理番茄果实中NO-3 N含量均不超过可生食标准 .适量施用钙肥有利于控制果实中NO-3 N含量 .氮肥对番茄植株地上部分和果实中N含量影响均符合报酬递减律 .氮肥和钙肥对番茄N素积累符合报酬递减律 ;番茄从开花期到果实膨大期属N素最大效应期 .番茄叶片硝酸还原酶活性受氮素影响较大 .N、Ca配合施用 ,有利于提高番茄叶片硝酸还原酶活性 ,钙素可降低硝酸还原酶活性 .土壤中NO-3 N含量和电导率EC值均随氮肥施用增加而提高更多还原

【Abstract】 To study the effect of fertilizer N and Ca on tomato plant,a pot experiment was conducted with meadow soil in Shenyang.The results showed that under the experimental condition,the N contents in stems,leaves and fruits decreased gradually along with the growth stages.For all treatments,the NO - 3-N content in fruits,which was within the raw eatable standard,had a positive correlation to N fertilization level.Adequate application of Ca was useful to control the NO - 3-N content.The response of N contents in stems,leaves and fruits to fertilizer N and Ca was in line with the law of diminishing marginal returns.From flowering stage to fruit expanding stage,the response of fertilizer N was most activated.The nitrate reductase activity in leaves might be greatly affected by fertilizer N,while adequate Ca fertilization could decrease it.A combined application of N and Ca could promote the nitrate reductase activity. Both soil NO - 3-N content and electric conductivity (EC) were increased with the increasing amount of applied fertilizer N.更多还原