摘要
以‘甘农3号’紫花苜蓿为材料,采用砂培方法,研究了硝态氮和铵态氮对紫花苜蓿根系生长、根系活力、地上部和地下部全氮含量、根瘤数量和固氮酶活性的影响.结果表明:铵态氮培养下,‘甘农3号’紫花苜蓿的根系及根瘤生长、根系活力、地上部和全株全氮含量、固氮酶活性均好于硝态氮培养;在不同形态氮素培养下接种根瘤菌,紫花苜蓿的根系活力、根瘤数量和固氮酶活性均高于不接菌紫花苜蓿;供氮条件下接菌与不接菌紫花苜蓿的根体积、根干质量、根系活力、有效根瘤数和固氮酶活性均高于无氮培养;接种12531根瘤菌的紫花苜蓿的根系活力、各部位全氮含量、根瘤数量和固氮酶活性在供氮及无氮培养下均好于接种LW107根瘤菌.总体而言,甘农3号紫花苜蓿接种12531根瘤菌在铵态氮培养下的结瘤固氮能力更强.
The sand culture with nutrient solution was used to study the effects of NO-3-N and NH＋4-N on root growth,root activity,above and under-ground nitrogen content,nodule number and nitrogenase activity of alfalfa（cv.Gannong 3）.The results showed that root and nodule growth,root activity,shoot and whole plant nitrogen content,nitrogenase activity grown in NH＋4-N nutrition showed better than those grown in NO-3-N.Root activity,nodule number and nitrogenase activity of alfalfa inoculated with rhizobia that grown under different nitrogen forms were found higher than un-inoculated alfalfa plants.Root volume,root dry weight,effective nodule number and nitrogenase activity of inoculated and un-inoculated alfalfa supplied with nitrogen were found higher than those N-free plants.According to the comparison of the two rhizobia,root activity,total nitrogen content of different parts of the plants,nodule number and nitrogenase activity of alfalfa inoculated with 12531 performed better than alfalfa inoculated with LW107 in both N and N-free environment.It is suggested that the ability of nodulation and nitrogen fixation of alfalfa inoculated with 12531 and grown in NH＋4-N is better.
出处
《甘肃农业大学学报》
CAS
CSCD
北大核心
2011年第5期106-110,共5页
Journal of Gansu Agricultural University
基金
甘肃省科技厅自然科学基金(1010RJZA157)
