title: [Interactive effect of N and Ca on N uptake by tomato].
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 NO3(-)-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 NO3(-)-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 NO3(-)-N content and electric conductivity (EC) were increased with the increasing amount of applied fertilizer N.
authors.affiliation: Institute of Soil and Fertilizer, Liaoning Agricultural Academy of Sciences, Shenyang 110161, China. lcrlys@yahoo.com.cn
authors.forename: Chunrong
authors.initials: C
authors.lastname: Lou
authors.forename: Xiaori
authors.initials: X
authors.lastname: Han
authors.forename: Qianming
authors.initials: Q
authors.lastname: Xiao
authors.forename: Wentao
authors.initials: W
authors.lastname: Sun
authors.forename: Weiwen
authors.initials: W
authors.lastname: Qiu
authors.forename: Zhongxin
authors.initials: Z
authors.lastname: Fu
mesh_terms: D002118:Calcium / Q000494:pharmacology*; D002734:Chlorophyll / Q000378:metabolism; D004553:Electric Conductivity; D005308:Fertilizers; D005638:Fruit / Q000187:drug effects / Q000378:metabolism; D018551:Solanum lycopersicum / Q000187:drug effects / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism / Q000494:pharmacology*; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D018547:Plant Stems / Q000187:drug effects / Q000378:metabolism; D012987:Soil / Q000032:analysis
chemical_list: D005308:Fertilizers; D009566:Nitrates; D012987:Soil; D002734:Chlorophyll; D009584:Nitrogen; D002118:Calcium