Yellow Mite Research Articles

Effect of plant characteristics of jute varieties on incidence of pests in West Bengal, India

This study was conducted with a view to understand the effect of plant characteristics on the incidence of pests on most popular jute varieties, viz. JRO-524, JRO-632, JRO-878, JRO-7835 of olitorius jute and JRC-212, JRC-321, JRC-4444, JRC-7447 of capsularis jute. Correlation studies of plant characteristics with pest incidence in jute (Corchorus spp.) revealed that the basal girth of plant exhibited a positive significant relationship with the incidence of Apion corchori Marshall but not with other pests such as jute semilooper (Anomis sabulifera Guen.), Bihar hairy caterpillar (Spilarctia obliqua Wlk.), grey weevil (Myllocerus discolor Bohemus) and yellow mite (Polyphagotarsonemus latus Banks). However, plant height showed positive correlation with the incidence of all the major pests of jute. Leaf characteristics (number of leaves/plant, leaf area, leaf thickness, moisture and chlorophyll content of leaves of all the varieties recorded at three different growth stages, i.e. at 50, 80 and 110 days after sowing), number of leaves/plant had positive and significant relationship with the incidence of all the pests except stem weevil. However, leaf area and moisture content of leaves showed significant positive relationship with the incidence of yellow mite. Leaf moisture also showed a positive role on the infestation of grey weevil. Leaf thickness and chlorophyll content of leaves and stem, fibre thickness and moisture content of stem did show any significant effect on pest's incidence. Upon comparing the plant characteristics between the two jute species, olitorius varieties had greater fibre thickness than that of capsularis varieties but fibre thickness had no significant impact on incidence of pests.

Integrated Management Approach for Control of the Pest Complex of Olitorius Jute, Corchorus Olitorius L.

Integrated Management Approach for Control of the Pest Complex of Olitorius Jute, Corchorus Olitorius L. Field trials were conducted with six treatments against the pest complex of olitorius jute var. JRO-524 during 2004 and 2005 at Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India. The results revealed that incidence of Anomis sabulifera Guen., Spilarctia obliqua Wlk., Myllocerus discolor Bohemus, Apion corchori Marshall and Polyphagotarsonemus latus Banks were found causing a minimum of 6.10, 4.68, 12.38, 5.09, and 10.47 percent plant infestation, respectively. These were the results from the 2004 crop season in the IPM module M3 designed against insect, mite and nematode pests as compared to the other treatments. Similar results were obtained in 2005 with a relatively low plant infestation of 7.66, 28.60, 11.90 and 11.21 caused by A. sabulifera, M. discolor, A. corchori and P. latus, respectively, in module M3 as compared to the other treatments. The maximum reduction (69.39 to 82.46%) of root-knot nematode (Meloidogyne incognita Chitwood) population along with low gall index (1.33 to 1.67) at harvest was observed in module (M3) in 2004-05. The yellow mite population was observed to be a minimum of 14.33 and 19.33 per leaf in 2004 and 2005, respectively in M3. The maximum average fiber yield of 30.32 q/ha and the benefit-cost ratio of 7.34 were also recorded in M3. Based on the benefit-cost ratio, the performance of the treatments was in the decreasing order of M3 > M2 > M4 > M5 > M1 > M6. Considering performance for managing insect, mites and root-knot nematodes, M3 was the most effective and economical management strategy against the pest complex of olitorius jute. Four spider species viz. Neoscona mukerji Tikader, Neoscona sp., Araneus sp. and Xysticus sp. were recorded for the first time in the jute ecosystem of West Bengal. The pest population in the jute ecosystem could be suppressed naturally to a great extent, because thirteen insects and ten spider predators were encountered in the experimental field during the crop season. Furthermore, a larval parasitoid (Apanteles obliquae) was found acting on the larvae of bihar hairy caterpillars.

Integrated Management of the Yellow Mite, Polyphagotarsonemus latus (Banks), on Sweet Pepper Grown under Polyhouse

Different IPM modules were evaluated for the management of yellow mite, Polyphagotarsonemus latus (Banks) on sweet pepper grown under protected cultivation at the Indian Institute of Horticultural Research, Bangalore. Results indicated that application of module 1(spray of abamectin followed by ethion and abamectin) or module 2 (spray of abamectin followed by profenophos and abamectin) was significantly more effective (3.91-6.58 mites/ leaf) than module 3 (spray of dicofol followed by pongamia oil and neem seed kernal extract (5.79 -6.95 mites/ leaf) in the first two trials (Sept. 2002- Mar. 2003 and June - Dec.2003). IPM modules like module 4 (spray of dicofol followed by release of Amblyseius tetranychivorus and spray of Verticillium lecanii and module 5 (spray of dicofol followed by release of A. tetranychivorus and spray of pongamia oil (9.25-15.53 mites/leaf) were marginally effective during the first two trials. However, in the third trial (Mar. - Sept., 2004) all the revised modules, viz., abamectin followed by dicofol (M1), dicofol-fenazaquin (M2), fenazaquin-pongamia oil (M3) and organic module oxymetrin-neem soap (M4) were effective (2.30-3.03 mites/leaf) against the yellow mite.

Safety of pesticidal sprays to natural enemies in chilli (Capsicum annuum L.).

A study was conducted to assess the safety of three acaricides (Propargite 57 EC, Ethion 50 EC and Fenpyroxymate 5 SC), one insect growth regulator (Buprofezin 25 SC), four botanical pesticides (Neemgold 0.15 EC, Neem seed kernel Extract 5%, Clerodendron inermae aqueous leaf extract 5%, Vitex negundo aqueous leaf extract 5%), and formulations of two bioagents Verticillium lecanii and Paecilomyces fumosorosens to natural enemies associated with yellow mite, Polyphagotarsonemus latus (Banks) in chilli under field condition. The natural enemies observed were predatory coccinellid, Coccinella septempunctata Linnaeus, and the predatory mites, Amblyseius ovalis (Evans) and Amblyseins longispinosus (Evans). The botanical pesticides and formulations of bioagents were quite safe to predatory coccinellids and mites at tested doses. Among the synthetic acaricides, fenpyroxymate was quite safe to both predatory mite and coccinellid species and recorded on par results with the bioagents and botanical pesticides. Buprofezin and Neemgold were intermediate in their safety to predators.

Chemical control of sugarcane yellow mite(oligonychus sacchari hirst)

An experiment was conducted on chemical control of yellow mite (Oligonychus sacchari) using sugarcane variety CoS 767 during 3 consecutive years (1997-99) at farmer’s fields in Chhata factory zone of Mathura district. The chemical treatments included the spraying of plants with Endosulfan 35 EC, Monocrotophos 36 EC, Diclorvas 76 EC, Quinolphos 25 EC, Nethrin (each @ 1.25 lit/ha) and spraying of Lime sulphur wash (1:30). The results revealed that the spraying of plants with Lime-sulphur (1:30) as well as Nethrin (@ 1.25 lit/ha) gave significant and maximal reduction in the frequency of mite infestation as compared to rest of the treatments including control. The highest cane yield was also recorded under these treatments. Other chemical treatments were also effective in controlling the mite infestation but these were significantly inferior to Lime-sulphur and Nethrin. Hence, application of Lime-sulphur (1:30) and Nethrin (@ 1.25 lit/ha) may be recommended for effective control of yellow mite of sugarcane.

Control of cotton insect and mite pests in subtropical Africa: Current status and future needs

About 70 insects and five mites regularly or occasionally infest the cotton crop in subtropical Africa. The economic importance of these pests varies according to the climate and cropping pattern in the region. Cotton aphid, Aphis gossypii Glover and yellow tea mite, Polyphagotarsonemus latus (Banks) as foliage feeders and three bollworms, Pectinophora gossypiella Saunders, Diparopsis watersi Roths, and Heliothis armigera Hbn., during boll formation and development, are major pests. Pesticides have been used extensively to suppress the pest populations and infestation levels in the crop. Natural enemies of certain pests occur in the region, nevertheless, their effectiveness in pest control is not well-known or fully exploited. Research on yield loss evaluation, pest ecology, varietal resistance and cultural practices is underway in several countries. Therefore, a global pest management in cotton is discussed in the context of local conditions and perspectives are highlighted.

Pecan, Yellow Pecan Aphid and Leaf Scorch Mite Control, 1978

Abstract The experiment was conducted at Cleveland, MS. Four rates of Temik and an untreated check were tested in single-tree plots each replicated four times. Application was made on Jun 14 with an Easy-Flow applicator; then the insecticide was incorporated lightly with a drag harrow. The four rates were applied on the basis of tree-trunk-per-inch-diameter. On several dates after application, the mites and aphids present on 20 leaflets and 50 leaflets per plot, respectively, were counted.

Pecan, Yellow Pecan Aphid and Leaf Scorch Mite Control, 1977

Abstract The experiment was conducted at Shaw, Mississippi. The experiment was a completely random design with single-tree plots replicated 10 times. Application of the test materials was made on Aug 15 with a John Bean 757 sprayer calibrated to deliver 12 gal spray per tree. Evaluation was made on Aug 23 and 29 by counting the aphids present on 30 randomly selected leaflets per tree.

ESTIMATING MITE POPULATIONS IN SOUTHERN OREGON PEAR ORCHARDS

AbstractStudies were conducted in southern Oregon pear orchards to develop sampling methods for assessment of mite abundance. Those species included in the investigation were the two-spotted spider mite, Tetranychus urticae Koch; European red mite, Panonychus ulmi (Koch); yellow spider mite, Eotetranychus carpini borealis (Ewing); and the predaceous phytoseiid Typhlodromus occidentalis Nesbitt.The results show that five leaves on one limb per tree are adequate to include representative numbers of the four mite species. Variation in mite densities between trees, even of the same variety, was quite high. The sample size (numbers of trees) required for assessing mite density can be calculated provided that an estimate of the coefficient of variation (S/X) is available.