Evaluation of Some Botanical Extracts Against Major Insect Pests (Leafminer, Armored scale and Woolly Whitefly) of Citrus Plants in Central Zone of Tigray, North Ethiopia

Abstract

Citrus fruit production is suffering from various yield-limiting factors particularly the sucking pests viz, citrus leafminer Phyllocnistis citrella , woolly whitefly, Aleurothrixus floccosus and scale insects especially armored scales Aonidiella auriantii . The present paper tries to identify the effective botanical insecticides against these insect pests on citrus orange. An experiment was conducted in the established citrus orange farm in Kolla Temben at two farmer’s fields, Adiha and Agibe during the off-season of 2018 under irrigation growing condition in a randomized complete block design with six treatments and replicated thrice. The findings in both experimental sites showed that the neem seed extract had a significantly (P=0.001) lower leafminer infestation levels compared to the untreated control which is on par to the insecticide treatment of dimethoate. On the other hand, in both areas, whitefly mortality of more than 81% on average was recorded from neem seed extract followed by Tree tobacco (70%) (P=0.001). For scale insects however, in both experimental sites, the highest mean percent mortality was recorded from the insecticide dimethoate 40% EC (86.9%, 87.2 & 86.0%on average) followed by neem seed and tree tobacco extracts,70.1 and 65.4% respectively. The botanicals particularly the neem seed extracts followed by tree tobacco are as effective as the chemical insecticide, dimethoate 40% EC, even superior in some cases, in controlling the target pests. Therefore, these botanicals could be used as an IPM component for against the target pests.