Toxicity of selected biorational insecticides to Pulvinaria aurantii Cockerell and its predator,Cryptolaemus montrouzieri Mulsant in citrus field     

Amir Hossein Toorani  Leila Doostdar Kalkenari 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(8):723-729

The citrus cottony scale, Pulvinaria aurantii Cockerell, is the most important pest of citrus orchards in northern Iran in recent years. Owing to the harmful impacts of chemical insecticides, the use of biorational pesticides seems a safe and convenient way to control this pest. The present investigation was set up to study contact toxicity of various biorational and chemical compounds on the first, second instar nymph and overwintering adult of the citrus cottony scale, P. aurantii, and its predator, Cryptolaemus montrouzieri Mulsant under field conditions. The results indicated that the highest percentage of mortality of first instar nymph of the citrus cottony scale was observed in the Dayabon treatment of 9 and 10?ml/L, 100.0%?±?0.0% and the lowest percentage was observed in Palizin treatment of 1.5?ml/L, 34.7%?±?2.9%. In the second instar nymph, the highest mortality was seen in the Dursban treatment of 2?ml/L, 94.7%?±?2.4% and the lowest mortality in the Palizin treatment of 1.5?ml/L, 30.0%?±?2.3%. Also, for overwintering adults Dayabon 10?ml/L caused the highest mortality, 96.0%?±?4.0% during 24?h. In the case of ladybird insects, the highest and lowest percentage of mortality was observed in the Dursban treatment of 2?ml/L, 76.7%?±?8.8%, Dayabon 5?ml/L, and Palizin 2?ml/L, 3.3%?±?3.3%, respectively. The highest and lowest mortality rate of larvae of ladybird was estimated in the Dursban treatment of 2?ml/L, 83.3%?±?3.3% and Dayabon 5?ml/L, 3.3%?±?3.3%, respectively. Also, for overwintering predator adults Palizin 1.5?ml/L had the lowest mortality, 3.3%?±?3.3% during 24?h and this rate remain unchanged after 96?h after treatment. According to the results obtained, treatments with Dayabon 9 and 10?ml/L, can be a viable alternative to other high-risk chemical pesticides in addition to effectively controlling citrus cottony scale without having any adverse impacts on predator ladybird.  相似文献   

污泥对苗圃生长的银合欢幼苗发芽和初期长势的影响   总被引：1，自引：1，他引：0  

G.M.A.Iqbal  S.M.S.Huda  M.Sujauddin  M.K.Hossain 《林业研究》2007,18(3)

研究了不同类型的污泥(城市的、工业的和住宅污泥)对苗圃生长的银合欢幼苗田间萌发、生长和分枝的影响.播种前先将不同类型污泥的混合物与养分匮乏的自然林土壤混合.播种的3和6月后,记录幼苗大田发芽、分枝状况和其他物理生长参数(枝条或根长、活力指数、茎直径、叶片数、分枝或根鲜重和干重、总的生物量干重增长)等.与对照幼苗相比,混合污泥的土壤中生长的幼苗田间发芽、分枝状况及其他生长参数均发生了显著变化.与其它条件生长的幼苗相比,住宅污泥与土壤混合(1:1)条件生长的3月龄和6月龄幼苗分枝数和分枝鲜或干重均最高.就生长参数而言,住宅污泥与自然林土壤混合(1:1)生长的幼苗长势最好.研究表明:退化的土壤补偿以住宅污泥可促进银合欢的田间发芽、生长以及分枝的形成.图1表3参29.  相似文献