大豆锈病初次侵染源调查及其作用分析

本调查基本确定了大豆锈病(Phakopsora pachyrhiza syd.)在南方的越冬范围为北纬23°55′以南;经综合分析锈病发生时期、锈病专性寄生性和气流传播特性、栽培葛、野生葛和大豆种植时期、生长季节、锈病发生实况与接种鉴定结果,基本确定南方的栽培葛(Pueraria lobata ohwi)和野葛(P.lobata(wild)ohwi)是大豆锈病病原菌的越冬寄主,其上发生的锈病是本地大豆锈病的主要初次侵染源之一;该区域发生的病原菌成为向北传播扩散的起始源;为今后大豆锈病的监测、预测预报与治理提供了可靠的依据。

2020年草地贪夜蛾呈重发态势

近日,全国农业技术推广服务中心组织专家会商分析,今年草地贪夜蛾侵入我国区域广,国内外越冬范围广、虫源基数大,玉米等作物种植布局和气候条件有利,预计2020年草地贪夜蛾重发态势明显,发生形势极为严峻。发生区域涉及西南、华南、江南、长江中下游、江滩、黄淮、华北、西北玉米种植区,有迁入东北春玉米主产区的可能,发生区域占玉米种植区面积的80%以上,见虫区域超过1亿亩:各地区均有集中危害的可能,南方省份发生代次多、危害重。

Effect of the Microclimate of Underground Systems on the Occurrence of Hibernating Bats

This study investigates the microclimatic connections between underground systems and the hibernation sites of particular species of bats. The distribution of hibernating bats was analysed in five selected zones designated Ⅰ-Ⅴ. These zones have a similar relative humidity, diverse temperature ranges inside the system, as well as air flow rates. A multi-year research programme highlighted the relationships between the occurrence of hibernating bats of various species and the microclimate of these particular zones. What is of essential importance are the sites with an air flow in their zones exceeding 0.02 m·s^-1, then is temperature and humidity. The air flow determines more intensive settling of wintering bats （zones Ⅲ, Ⅳand Ⅴ）. The zone Ⅱ-tourist zone with periodic air flows and often visited by humans is the least used by hibernating bats.