Pesticidal Properties Of Chive (Allium Schoenoprasum)Against Cabbage Aphid (Brevicoryne Brassicae) In Rape (Brassica Napus)

The cabbage aphid is of agricultural concern vectoring at least 20 viral pathogens in crucifers. The aphids have demonstrated tolerance to a number of synthetic pesticides. Botanical pesticides are reasonably sustainable and effective in suppressing cabbage aphid populations in crucifers hence improved crop quality and yield per hectare. An experiment was run to test the efficacy of various concentrations of a botanical pesticide derived from chive (Alliumschoneoprasum) fresh leaf extract in controlling cabbage aphid (Brevicoryne brassicae) in rape. The experiment was laid out in a Complete randomized design (CRD) with four treatments and four replicates as follows; 12g chive extract, 8g chive extract, 4g chive extract and 0g control (water spray). Analysis of variance to separate mean mortality was done using Gens tat version 18 and least significant difference at 0.05 probability level was used to separate means. SPSS version 20 was used in estimating LC50 value and excel was used in calculating the regression equation. Significant differences (p<0.05) were observed throughout the trial, where highest mortality rates were observed in 12g chive extract (94.5%) and lowest mortality in control (12.2%) was observed. Pesticide concentration atLC50for the chive extract was estimated as a concentration of 7g/l. There were no observed signs of phytotoxicity even though other studies have shown that chances are high when the dose is increased. The experiments revealed that chive leaf extracts had pesticidal effects hence can be used to effectively control cabbage aphid in rape by smallholder vegetable producers.