Abstract: For understanding the influence of manganese fertilizer on the trace element nutrition of alfalfa,the effect of different application levels of manganese sulfate on alfalfa forage yield and trace element content was studied in 2006 year through leaf surface spraying.The results indicate that manganese sulfate spraying remarkably increased the yield of alfalfa(P<0.05) and treatment of 100 mg·kg^-1 level was the best and the forage yield increased by 24% in comparison with CK.Manganese sulfate spraying significantly increased the Mn,Fe,Zn,Mo,Co,and Se contents in alfalfa.Mn content in alfalfa was increased along with manganese sulfate concentration increasing and reached maximum when spraying concentration was 400 mg·kg^-1(Mn3 treatment).High manganese sulfate concentration restrained the absorption of Zn,Co,Mo,and Se and the contents of these trace elements in alfalfa reached maximum when spurting concentration was 100 mg·kg^-1(Mn1 treatment).Fe content in alfalfa reached maximum when spraying concentration was 200 mg·kg^-1(Mn2 treatment).While manganese sulfate spraying reduced the Cu and B contents in alfalfa.The annual accumulation of the above 8 trace elements increased significantly as the result of manganese sulfate spraying and Mn1 treatment had the best effectiveness.

Key words: Alfalfa, Manganese sulfate, Yield, Trace element content

摘要： 为了解外源锰肥对紫花苜蓿(Medicago sativa L.)微量元素营养的影响,于2006年采用叶面喷施的方法,研究不同锰水平对其草产量和微量元素吸收的影响。结果表明:喷施硫酸锰可以显著提高苜蓿草产量(P<0.05),以施锰量为100 mg·kg^-1的处理效果最好,与对照CK相比,产量可提高24%;施锰可显著地提高锰、铁、锌、钼、钴、硒,其中锰含量以Mn3处理(400 mg·kg^-1)最高,即苜蓿锰含量随施锰量的增加而增加,但苜蓿锌、钴、钼和硒含量以Mn1处理(100 mg·kg^-1)最高,施加高浓度的锰却降低植株内含量;而铁含量以Mn2处理(200 mg·kg^-1)最高;喷施锰肥后苜蓿铜、硼含量有所降低,并随外加锰浓度的增加而降低;喷施硫酸锰能显著地提高8种微量元素的年积累量(P<0.05),其中Mn1(100 mg·kg^-1)处理效果最好。

关键词: 紫花苜蓿, 硫酸锰, 草产量, 微量元素含量