木薯氮素营养状况的SPAD仪诊断  

Diagnosis of Cassava Nitrogen Nutrition Status by Using Chlorophyll Meter SPAD-502

作　　者：柳红娟[1] 欧燕楠[1] 刘子凡[1] 黄洁[2] 

机构地区：[1]海南大学农学院,海南海口570228 [2]中国热带农业科学院热带作物品种资源研究所,海南儋州571737

出　　处：《西南农业学报》2012年第6期2153-2156,共4页Southwest China Journal of Agricultural Sciences

基　　金：现代农业产业技术体系建设专项资金资助(CARS-12-hnhj)

摘　　要：本文以华南8号为材料,研究了不同生育时期木薯叶片SPAD值、鲜薯产量以及淀粉产量随土壤供氮水平的变化规律及其相互关系。结果表明:①在块根形成期和块根膨大期,叶片SPAD值随土壤施氮量表现为线性加平台的模式,而在块根工艺成熟期仅表现为线性模式。②不管是在块根形成期、块根膨大期和块根工艺成熟期,木薯叶片SPAD值与块根鲜薯产量和淀粉产量之间均呈现二次函数关系,据此确定了在块根形成期、块根膨大期和块根工艺成熟期应用叶绿素仪SPAD-502进行木薯推荐施肥的SPAD临界值:鲜薯产量最大时分别为45.19、43.09、40.63,淀粉产量最大分别为44.31、42.49、40.51。③若在块根形成期、块根膨大期和块根工艺成熟期观测SPAD值小于临界SPAD一个单位,且施氮量小于1.98 kg/667m2时,则应增加的施氮量分别为0.42、0.63和1.34 kg/667m2;若施氮量大于1.98 kg/667m2,追氮量则需进一步研究。In this paper, taken the cassava variety of SC8 as tested materials, the change of cassava leaf SPAD value, fi^sh cassava yield and starch yield during different growth period were studied with nitrogen supply. The results showed that （i） at the root initiation stage and the root bulking stage, the leaf SPAD value varied with nitrogen fertilization levels in linear-plateau regression modes, and in linear regression modes at the root technical maturity stage; （ii） Fresh cassava yield and starch yield varied with the leaf SPAD value in a quadratic-function modes at root initiation stage, root bulking stage and the root technical maturity stage, and the threshold SPAD values of different growth sta- ges of cassava were obtained by SPAD-502, which were critical for the instruction of nitrogen fertilization in cassava. SPAD values were 45. 19, 43.09, 40.63, respectively, in the highest fresh cassava yield in above three stages and 44.31,42.49, 40.51, respectively, in starch yield; （iii） when the observed SPAD value was less one unit than the critical SPAD value at the three stages, and the amount of nitrogen application was less than 1.98 kg/667m^2, the increasing amount of nitrogen apply were 0.42, 0.63 and 1.34 kg/667m^2 in the three stages. The amount of nitrogen application was more than 1. 98 kg/667m^2 and the additional application amount would be studied in advance.

关 键 词：木薯 SPAD值 氮素营养诊断 

分 类 号：S533[农业科学—作物学]