Biological activity of horticultural mineral oils against thrips and mites on Kinnow
Loading...
Date
2018
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Punjab Agricultural University, Ludhiana
Abstract
The studies on biological activity of horticultural mineral oils against thrips and mites on Kinnow were carried out at Fruit Research Farm/Old orchard and Entomology Laboratory, Department of Fruit Science, Punjab Agricultural University, Ludhiana, during 2016 and 2017 with the objective to evaluate the biological activity and phytotoxicity of different HMOs against thrips and mites on Kinnow. Eight year old trees of Kinnow were sprayed with five different horticultural mineral oils (HMOs), viz. MAK All Season, Servo, Arbofine, Sparrow 888 Plus and HPHMO at different concentrations (0.75, 1.00, 1.25, 1.50 and 2.00% for efficacy and 3.00 and 4.00% for phytotoxicity) alongwith insecticide/acaricide i.e. triazophos 40 EC and fenazaquin 10 EC as check and untreated control (in which only water was sprayed) at 15 days interval during March, April, May and June with the help of Rocking/Foot pump sprayer. The results on the evaluation of HMOs against citrus thrips, Scirtothrips citri showed that triazophos (0.075%) was found to be the most effective treatment against thrips upto 15 days after spray. All the HMOs at different concentrations three days after spray reduced the thrips population marginally and provided about 40 per cent control of thrips upto seven days after treatment. Similarly, in case of mites, fenazaquin (0.015%) was found the most effective treatment as compared to different HMOs. As in case of thrips, HMOs also reduced the mite population by 40-50 per cent upto seven days after treatment. The results further showed that with the increase in concentration of each HMO, the efficacy against thrips and mites increased. Among different HMOs, Arbofine was found to be numerically better both against thrips and mites. Similar results were also found against predatory mite, Amblyseius spp. where population was reduced marginally with the application of HMOs. The rind scarring of fruits due to thrips and mites also decreased with the application of HMOs. Fruits free from scarring increased from 40.00-49.17 per cent at 0.75 per cent to 64.17-75.83 per cent fruits at 2.00 per cent of each HMO spray as compared to 12.50 per cent in untreated control. It was also found that with the increase in concentration of HMOs, there was an increase in the deformity of the leaves in terms of leaf hyponasty, epinasty and yellowing. Trees treated with 4.00 per cent concentration of HMOs had only 55.00-60.00 per cent normal leaves as compared to 90.00 per cent in untreated control. Thus, it is concluded that with the increase in the concentration of HMOs, though there was an increase in the efficacy against thrips and mites but there was more phytotoxic effect on leaves if the concentration of HMOs is more than 2.00 per cent.
Description
Keywords
null