Efficacy of Miticides Against Two-Spotted Spider Mite, Tetranychus urticae, Infesting Three Almond Varieties

摘要

The efficacy of three miticides viz. Pyrida, Ethion and Agrifol was tested against two-spotted spider mite. Tetranychus urticae Koch (Acari: Tetranychidae) on three almond (Prunus dulcis) cultivars viz. Ferraster. Karishma and Lajawab. All the three miticides significantly reduced the mite populations on all the tested cultivars as compared to the check. Pyrida was the most effective miticide, followed by Ethion and Agrifol. Mean mite populations after three cumulative splays oil these varieties recorded per leaf after 1, 3, 7. 10 and 15 days was 0.52, 0.22, 2.44, 3.19 and 3.85. respectively, with Pyrida: 2.04, 0.96, 3.70, 5.04 and 6,22, respectively, with Ethion: and 3.93, 2.63, 6.07, 8.74 and 10.55, respectively with Agrifol, as compared with 42.22. 47.37, 46.52, 54.15 and 57.18 for the check. Overall mean mite population after three spays on three varieties, Ferraster, Karishma and Lajawab was noted as 4.87, 1.91 and 2.60 for Pyrida, 2.82, 3.09 and 4.86 for Ethion, and 5.00. 5.62 and 8.54 for Agrifol as compared to 48.24, 48,56 and 56.71 mite per leaf on untreated trees, respectively, It is concluded from these results that Pyrida was the best insecticide followed by Ethion and Agrifol for the control of T. urticae on the basis of their performance; three sprays are recommended. Variety Lajawab was more susceptible to T. urticae than Ferraster and Karishma.