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Sixteen isolates of bacteria obtained from the entomopathogenic nematode (Heterorhabditis sp.) infected cadavers of Galleria mellonella larvae were identified following phenotypic characterization and molecular analysis of 16S rRNA. Two isolates were identified as the symbiotic bacterium, Photothabdus luminescens, while 14 other isolates were represented by nine species of nonsymbiotic bacteria viz., Stenotrophomonas maltophilia, Alcaligenes aquatilis, Brevundimonas diminuta, Brucella pseudointermedia, Ochrobactrum sp., Brucella pseudogrignonensis, Brucella anthropic, Pseudomonas azatoformans and Pseudomonas lactis. The phylogenetic analysis confirmed the evolutionary relationship between P. luminescens and Pseudomonas spp. The study also found a close relationship among the nonsymbiotic bacteria such as A. aquatilis, B. diminuta, Ochrobactrum sp., and Brucella spp. P. luminescens has been documented for its insecticidal effects against a wide range of insects. The two local isolates obtained in this study may be explored for their biocontrol potential against major pests of the region. Further, the association of nonsymbiotic bacteria with the EPN may be investigated. [ABSTRACT FROM AUTHOR]

Coccinellidae is a diverse and species-rich family that includes predaceous, phytophagous and mycophagous insects, which are significant to agriculture. This study aimed to estimate the diversity of coccinellids and document their associated prey in agricultural fields of northern Kerala, India and to generate DNA barcodes for the species collected during the study. Twenty-seven species under seven tribes were reported in this study, which includes three phytophagous, two mycophagous and 22 predaceous beetles. The information on prey species and/or host plants of the beetles are given furnished. Diversity indices of coccinellids across different agroecological zones and crops of northern Kerala were estimated. Mitochondrial cytochrome oxidase subunit I sequences of 18 species were generated and phylogenetic analysis was carried out. Coccinellini was recorded as the predominant tribe of Coccinellidae in northern Kerala. High hills were found to be the most diverse agroecological zone for Coccinellidae, whereas plantation crops and vegetables were the most diverse crop ecosystems. [ABSTRACT FROM AUTHOR]

Armored scale insects (Hemiptera: Diaspididae) are major economic pests and are among the world's most invasive species. Most armoured scale insect pests are invasive and with increased international trade, these concealed and cryptic pests pose a serious threat to the world agricultural economy causing economic losses in the US to be as high as $1 billion annually. Aulacaspis Cockerell is one of the largest genera of armoured scale insects with 151 species known worldwide, and 23 species from India. Five species of Aulacaspis are associated with Cycas spp. throughout the world. Through this correspondence, we report the occurrence and severe infestation of A. maduinensis (Zehntner) on C. circinalis from India, though it has been reported to infest other species of Cycas from elsewhere. We provide information about nature and extent of damage, field and taxonomic diagnostic characters which will be helpful in quick diagnosis of the pest, monitoring its spread to different geographical areas, and generation of awareness about the pest species to avoid further economic loss. [ABSTRACT FROM AUTHOR]

Efficacy of solvent fractions of Tagetes minuta L. (hexane, chloroform and aqueous fractions of aerial parts) was evaluated against Aphis craccivora Koch at five different concentrations (0.025, 0.05, 0.1, 0.15 and 0.2%) in the laboratory. At higher concentrations, all the fractions recorded significant reduction in aphid count; maximum reduction after 120h of treatment was in hexane fraction at 0.2 per cent (90.00%), followed by chloroform fraction at 0.2 per cent (86.67%) and aqueous fraction at 0.2 per cent (85.00%). The best concentrations of the three solvent fractions of T. minuta identified in the laboratory were evaluated against the aphid on cowpea, in a pot culture experiment. By 10th day of treatment, all the fractions at 2 per cent concentration reduced population of aphids, with the highest reduction in hexane fraction. [ABSTRACT FROM AUTHOR]

For many decades, mites are posing threat to agricultural and horticultural industries. Recently mite infestation in Horticultural nurseries has become serious problem in Kerala, India. Purposive sampling surveys were eonducted in the Horticultural nurseries of Thrissur and Ernakulam districts to record the incidence of mite pests on nursery plants. Study of morphologicae characters like setae and aedeagus confirmed the mite species infesting TC bananf plants is Tetranychus gloveri Banks. [ABSTRACT FROM AUTHOR]

The potential of aqueous and methanol extracts of ten botanicals were evaluated against the egg and adult of the spider mite Tetranychus truncatus Ehara, under laboratory conditions. The extracts showed no or negligible ovicidal action, but significant adulticidal action; among the aqueous extracts, A. squamosa (5, 7.5 and 10%), C. papaya (10%) and B. monnieri (10%) caused significantly maximum mortality, while it was methanolic extracts of A. calamus, C. papaya (1 and 2%) and A. marmelos (2%) which revealed maximum mortality with adults. [ABSTRACT FROM AUTHOR]

A field study was conducted to evaluate the efficacy of horticultural mineral oil (HMO), combination of HMO + neem oil and neem oil 2 per cent along with a synthetic acaricide, Spiromesifen 240SC and an untreated control against Tetranychus truncatus on okra during March, 2018. The plots treated with HMO at 2.5 (92.60%) and 3.0 per cent (93.90%) as well as combination treatments HMO 2.5 per cent + neem oil 2.0 per cent (94.14%) and HMO 3.0 per cent + neem oil 2.0 per cent (96.79%) recorded significant reduction in mite population and were superior to plots treated with either spiromesifen (91.08%) or neem oil alone at 2.0 per cent (90.42%). The high efficacy of HMO against the spider mite T. truncatus brought out in the study suggests that HMO can be an effective tool for mite management in vegetable crops. [ABSTRACT FROM AUTHOR]

Cucumber is one of the most preferred crops grown in polyhouses of Kerala. However, incidence of spider mite, Tetranychus urticae Koch, 1836 as emerged as an important limiting factor for cucumber cultivation in the polyhouses. Increasing concern over the abuse of acaricides for mite management in polyhouses has necessitated development of alternative strategy with emphasis on biological control. The phytoseiid mite, Neoseiulus longispinosus (Evans, 1952) which has a wide distribution and has the ability to adapt to warm temperatures can be a potent candidate against tetranychid mites. To identify the optimum predator: prey ratio of N. longispinosus to T. urticae for effective management of spider mites, experiments were conducted both in the laboratory as well as polyhouse using a range of ratios. In the laboratory, the experiment was carried out on excised cucumber leaves maintained on moist sponge in plastic trays. Gravid females of N. longispinosus were released to 100 mixed stages including eggs, nymphal stages and adults of prey on cucumber leaves at predator: prey ratios of 1:5, 1:10, 1:20, 1:25, 1:33, 1:50 and 1:100. In the polyhouse, hundred mixed stages of T. urticae were released on four leaf stage of twenty days old cucumber plants at the rate of 25 mites/leaf, followed by the release of gravid females of N. longispinosus at predator: prey ratios of 1: 20, 1: 25, 1: 33 and 1:50. Laboratory studies showed that, at ratios of 1:5 and 1:10, the prey population was significantly reduced by third day. The prey was completely eliminated by seventh and tenth day at ratios 1:5 and 1:10 respectively. Ten days after the release, the prey population at ratios, 1 20, 1:25 and 1:33 were on par with that of 1:5 and 1:10. In the polyhouse, the predator: prey ratios of 1:20 and 1:25 were significantly superior in reducing the population of T. urticae on cucumber. The present study has revealed the potential of the predatory mite, N. longispinosus as a biocontrol agent against T. urticae on cucumber in polyhouse. [ABSTRACT FROM AUTHOR]

Field study was conducted to evaluate two acaropathogenic fungi (Hirsutella thompsonii and Beauveria bassiana), two botanicals [neem oil 2 per cent and neem seed kernel extract (NSKE)5 per cent] and three new acaricide molecules (Fenazaquin 10 EC, Diafenthiuron 50 WP and Spiromesifen 240 SC) along with a standard check (Dicofol 18.5 EC) and an untreated control against Tetranychus urticae on okra during two seasons viz., February-May, 2012 and November, 2012-February, 2013. The new acaricide molecules fenazaquin 10 EC, diafenthiuron 50 WP and spiromesifen 240 SC exhibited high efficacy against T. urticae and significant reduction in mite population was observed ten days after treatment application. Among the botanicals evaluated, neem oil 2 per cent was found to be superior to NSKE 5 per cent during the second season, though on par with each other during the first season of study. Among the acaropathogenic fungi, B. bassiana was found to perform better than H. thompsonii during first season and was on par with each other during the second season. The study identified three novel acaricide molecules for the effective management of T. urticae though the bio-agents and botanicals did not give consistent results during the two seasons of study. [ABSTRACT FROM AUTHOR]

Laboratory bioassay was conducted to evaluate the relative toxicity of four new acaricide molecules viz., fenazaquin 10 EC, spiromesifen 240 SC, fenpyroximate 5SC and propargite 57SC, two botanicals, azadirachtin 0.005 per cent and neem oil 2 per cent and wettable sulphur along with a standard check dicofol 18.5 EC against rice leaf mite, Oligonychus oryzae. Fenazaquin was found to be the most effective molecule which recorded 100 per cent mortality of gravid females 24h after treatment application. It recorded an egg mortality of 86.60 per cent at 72 h. At 72h, spiromesifen recorded 80 per cent egg mortality and 100 per cent mortality of gravid females. Propargite recorded a mortality of 83.30 per cent of eggs and 90 per cent of gravid females. Efficacy of fenpyroximate though found to be superior over standard check, dicofol, was found to be inferior to other novel molecules and on par with wettable sulphur. The efficacy of botanicals was found to be inferior to standard check, dicofol. [ABSTRACT FROM AUTHOR]

The article offers information on the presence of invasive azedarach scale Aulacaspis crawii in India. It mentions that alien invasive species posed major economic and environmental threats that affect ecosystems, human health and economies. It also presents information on invasive species natural enemies that would lead to the biological control of the new entrant and thus minimize the economic losses.