不同质地潮土冬小麦SPAD值在氮素营养诊断上的应用研究

SPAD value of winter wheat as an indicator for nitrogen nutrition diagnosis in different texture fluvo-aquic soil

为建立不同质地潮土冬小麦氮素营养诊断指标,以豫农949和豫麦49为供试材料,在砂质和壤质潮土上,设置5种施氮水平,分别为0、90、180、270和360 kg·hm(^-2),研究不同施氮水平对冬小麦产量和叶片SPAD(Soil and Plant Analyzer Development)值的影响。结果表明,在2种类型潮土上,2个冬小麦品种的产量均随施氮量的增加先增加后降低,壤质潮土上2个冬小麦的产量显著高于砂质潮土。2个冬小麦品种在砂质潮土上拔节期顶1叶、孕穗期顶1叶和顶2叶的SPAD值与产量显著相关,在壤质土壤上返青期顶1叶、孕穗期顶1叶和孕穗期顶2叶的SPAD值与产量显著相关。拔节期顶1叶、孕穗期顶1叶和顶2叶的SPAD值可以作为砂质潮土上冬小麦氮素营养的诊断时期和部位,诊断临界值为47.06、44.95和45.08。返青期顶1叶、孕穗期顶1叶和孕穗期顶2叶的SPAD值可以作为壤质潮土上冬小麦氮素营养的诊断时期和部位,诊断临界值为54.80、52.58和55.01。

To establish nitrogen nutrition diagnostic index of winter wheat in different texture alluvial soils,the effects of different amounts of nitrogen fertilizer on yield and SPAD value of different leaf positions of winter wheat were studied.Yu Nong 949 and Yu Mai 49 of wheat cultivars were used as model materials.Five fertilization rates of nitrogen(0,90,180,270,360 kg·hm-2)were applied in field trial.The results showed that the yields of two cultivars firstly increased then decreased with an increase of the nitrogen rate.Wheat yield in loamy fluvo-aquic soil was higher than those of sandy fluvo-aquic soil.In the sandy fluvo-aquic soil,the SPAD value of top 1 leave at jointing stage,top 1 and 2 leaves at booting stage were significantly correlated with wheat yield.In the loamy fluvo-aquic soil,the SPAD value of top 1 at turning green,top 1 and 2 leaves at booting were significantly correlated with wheat yield.The SPAD value of top 1 leave at jointing stage,top 1 and 2 leaves at booting can be used as diagnostic time and location in the sandy fluvo-aquic soil,which the critical value of SPAD were 47.06,44.95 and 45.08,respectively.The SPAD value of top 1 at turning green,top 1 and 2 leaves at booting stage can be used as diagnostic time and location in the loamy fluvo-aquic soil with the critical value of 54.80,52.58 and 55.01,respectively.