陇南山区小麦条锈病流行程度预测模型

利用1957-2006年陇南山区小麦条锈病资料分析得出：白龙江流域小麦条锈病在海拔1600m以上自生麦苗上越夏，在海拔1000m以下的川坝河谷地无明显的越冬期，春季流行以当地菌源为主，西汉水流域海拔1600m以上区域是陇南小麦条锈病的主要越夏区。小麦感病品种面积比率，上年条锈病越夏菌量、秋苗病情病田率和上年8月、10月及当年1月、3月平均气温与春季小麦条锈病流行程度相关十分显著，10月一次年3月平均气温与小麦条锈病流行程度呈正相关，4—8月平均气温与小麦条锈病流行程度呈负相关，逐月降水量与小麦条锈病流行程度呈正相关，由此建立的预报模型，其历史拟合率可达87．5％，其中偏重到大流行历史拟合率为100％，2006年在业务应用中预报正确。

Prediction Model on Seripe Rust Influence Extent of Winter Wheat in Longnan Mounain Area

Based on the data from 1957 to 2006 in Longnan City,the prevalence rules of the stripe rust of winter wheat were analyzed.The prediction model was established and validated.The results showed that the stripe rust of winter wheat in Bailongjiang river area oversummered at the regions with an altitude over 1600 meters,while there was no obvious over-wintering of the stripe rust in the river valley and plain areas below 1000 meters,where the local stripe rust was the main sources of the stripe rust in the spring.The areas with an altitude over 1600 meters in the Xihanshui river were the main regions of over-summering of the wheat stripe rust for the Longnan area.The area percentage of the infected varieties of winter wheat,the over-summered stripe rust count from the last year and the infection rate in autumn,together with the mean temperature in the last August,last October,January and March,were significantly related to the prevalence of the stripe rust of winter wheat in the spring.The prevalence of the stripe rust of winter wheat was positively related to the mean temperature from October to March,while it was negatively to the mean temperature from April to August.The monthly precipitation was positively related to the prevalence of the stripe rust of winter wheat.