套袋果樹的果實在成熟期前後出現的黑點、黑hei斑ban,大da多duo情qing況kuang下xia是shi在zai幼you果guo期qi噴pen灑sa的de藥yao劑ji種zhong類lei或huo質zhi量liang不bu合he適shi,造zao成cheng幼you果guo果guo皮pi受shou傷shang,給gei一yi些xie寄ji生sheng菌jun提ti供gong了le侵qin入ru通tong道dao,最zui終zhong在zai果guo麵mian上shang形xing成cheng黑hei色se或huo褐he色se斑ban點dian。在zai小xiao麥mai拔ba節jie後hou依yi然ran大da劑ji量liang使shi用yong2,4—Ddingzhi,huizaochengxiaomaisuifenhuashoudaoraoluan,xiaomaichousuihouwangwangchuxianniuqujixingdemaisui。dajiliangshiyongbenhuanglong,duixiachadehuashengyehuizaochengyinxingyaohai,chuxianhuashengshengchangman、根係不長等症狀。
不少農藥,尤其是除草劑,往往會對某類作物或作物的某一生育階段,有較明顯的敏感性。比如桃樹對銅製劑、敵敵畏、敵百蟲、樂果、殺撲磷等敏感,花生對苯磺隆、甲磺隆等磺酰脲類除草劑敏感,小麥對毒死蜱、莠去津敏感,瓜類對氟矽唑、binghuanzuodengmingan。yixieliezhiyaojiyetebierongyizaochengchuyuminganshiqidezuowuchuxianyaohai。youdenongminweileshenggong,youshihoubabenyingfensantongshuideyaojidaojinyitongshuili,rongyishizuowujubuyaojiguoliangdaozhiyaohaichansheng。
規避藥害的要領有三個。一是合理選擇農藥,盡量不選用容易對作物敏感的藥劑種類;二是選擇合適的天氣條件使用農藥,避開高溫、幹旱、高濕、低溫、寡照或高光照時噴灑農藥;三是嚴格按要求劑量和操作規程用藥,準確計算使用劑量,分步稀釋,噴完除草劑以後要盡快清洗噴霧器械。
手機版




