Percentage of diseased hill holerate is the secondary factor.The occurrence extent of false smut of rice mainly depended on the quantity of chlamydospore that over-wintered last year.

• 根据田块中的厚垣孢子含量推断，影响水稻稻曲病发病程度的主因素可能是上年的厚垣孢子在田间的越冬量。