内蒙古中部地区苜蓿锈病发生规律的初步研究

Occurrence of Alfalfa Rust in Central Inner Mongolia

在内蒙古中部地区，苜蓿锈病可于６月上旬始见发生，病害高峰期一般出现在７月下旬至８月上旬以后。通过对１９９２～１９９４年病害发生发展的调查与当地气象资料的分析，发现病害高峰出现的早晚，以及病害程度的轻或重，主要与当年４～８月的降水量及其分布有密切关系。降水量较多又分布较均匀的年份，病害高峰期出现较早，发病程度较重，反之病害高峰期较晚，发病较轻。

The occurrence of alfalfa rust in the central part of Inner Mongolia begins in early June, with its peak appearing in the period from late July to late August. An investigation of the incidence of alfalfa rust during 1992～1994 and an analysis of local climatic data for the same period indicate that the time of peak appearance and the degree of damages caused by the disease are highly correlated with the amount of rainfall for April-August and its distribution during that period. In a year with ample rainfall and a relatively even distribution, the peak of the disease comes earlier and its impact would be more severe than in an average year.