不同施氮方式对龙桑一号生物量及生理特性的影响

Effects of different N application methods on biomass and physiological characteristics in Longsang No.1

为确定适宜的桑树施氮方式,提高氮肥有效利用率,获得较高产量和好的经济效益,以龙桑一号为材料,研究了不同施氮方式下龙桑一号的生长和生理特性。结果表明:距桑树根部20 cm穴施(T20处理)和距根部20 cm深环施处理(Th处理)的品种单株条数、单株叶片数、单株叶片叶面积、叶片鲜质量、叶片干质量和单株产叶量显著高于另外2种处理。不同施氮方式间桑树的每hm2产量差异显著,T20和Th处理的每hm2的产量远高于对照处理,增产率分别为64.26%和65.22%。叶绿素含量在T20处理和Th处理下达到最大,差异不显著。可溶性蛋白含量在T20处理下最高,但是各处理间差异不大。不同施氮方式对供试品种的可溶性糖含量无明显影响。T20处理和Th处理对供试品种的全氮含量在测定初期的促进作用较明显,与距桑树根部10 cm穴施和距根部30 cm穴施处理差异显著。Th处理对供试品种全磷含量的促进作用最大,与其它3种处理差异显著。从试验结果来看,T20和Th处理效果更佳。

In order to determine an optimal N application method of mulberry,to improve nitrogen use efficiency,and to obtain higher yield and good economic benefit,taking Longsang No.1（Morus alba L.cv Longsang No.1） as test materials,growth and physiological characteristics were researched under different N application methods.The results show that the number of branches per plant,the number of leaves per plant,the leaf area,fresh leaf mass,dried leaf mass and leaf yield per plant in T20（application in small holes at 20 cm from roots） and Th（deep circulating application at 20 cm from roots） treatments are significantly higher than those in the other two treatments.Leaf yield per hectare in mulberry among nitrogen application methods were significant different,and yields in T20 and Th are much higher than that in CK treatment,increasing by 64.26% and 65.22%,respectively.The chlorophyll content in Longsang No.1 in T20 and Th treatments get the top point,but no significant differences exist among all treatments.Soluble protein content in leaves of mulberry of T20 treatment is the highest in all treatments,but no significant differences exist among the treatments.Different nitrogen application methods have little effect on soluble sugar content in leaves.T20 and Th treatments increase significantly nitrogen content in leaves of mulberry at initial stage of determination,which have significantly differences compared with T10（application in small holes at 10 cm from roots） and T30（application in small holes at 30 cm from roots） treatments.Total phosphorus content in Th treatment is the highest,and there is significant difference compared with the other three treatments.From the result,T20 and Th treatment are much better than other treatments.