Effect of concentrations and time of kaolin spraying on wheat aphid

Abstract

Common wheat aphid (Schizaphis graminum Rondani) is the cereal key pest. To study the effectiveness of different concentrations and times of kaolin spraying on the reduction of S. Graminum damage, a field experiment was arranged based on randomized block design with 4 replicates. Treatments were kaolin concentrations at four levels [0, 1.25 %, 2.5 % and 3.75 %, k1, K2, k3, and k4, respectively], times of kaolin spraying at three levels (concurrently with the stem forming, coincides with the first appearance of spikelets, coincides with dough development, T1, T2 and T3 respectively. The results indicated that the maximum (9914.81 kg ha -1 ) and minimum (6277.76 kg ha -1 ) grain yield were found in plots received 3.75 % kaolin at T2 time and untreated control, respectively. The highest (22666.66 kg ha -1 ) and lowest (16465.92 kg ha -1) biological yield were detected in plots exposed to kaolin 1.25 % at T3 time and control treatment, respectively. The present study showed that Kaolin could reduce wheat aphid damage and had positive effect of grain and biological yields. Therefore, Kaolin can be an important and effective tool to mitigate wheat aphid damage, and could be a good alternative to chemical products.