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Exotic invasive whiteflies (Hemiptera: Aleyrodidae) in India cause direct and indirect yield losses in agriculture, horticulture and forestry crop plants. Around 25 years ago, the spiralling whitefly, Aleurodicus dispersus Russell invaded and established on many host plants including economically important crops in India. Recently, within a span of five years, seven whiteflies invaded India viz., solanum whitefly, Aleurothrixus trachoides (Back) reported to breed on 37 plant species; rugose spiraling whitefly (RSW), Aleurodicus rugioperculatus Martin found breeding on 40 host plants; nesting whiteflies, Paraleyrodes bondari Peracchi on 34 host plants and P. minei Ιaccarino infest about 25 host plants; legume feeding whitefly, Tetraleurodes acaciae (Quaintance) infesting 5 host plants; palm infesting whitefly, Aleurotrachelus atratus Hempel on 4 host plants and woolly whitefly, Aleurothrixus floccosus (Maskell) infesting guava. These invasive species are native to the Neotropical region, mostly from Central America and the Caribbean. Extensive spread along the coastal regions and gardens near the backwater of India is predicted owing to the favorable weather factors and availability of host plants. Species of exotic whiteflies with similar habits co-exist in more or less the same niche and have a similar pattern of growth and development. The intensity of infestation of RSW on coconut, banana and oil palm, the woolly whitefly on guava and the palm infesting whitefly and nesting whiteflies on coconut was severe. The exotic aphelinid parasitoid, Encarsia guadeloupae Viggiani (Hymenoptera: Aphelinidae), a predator Pseudomallada astur (Banks) (Neuroptera: Chrysopidae) and the entomopathogenic fungus, Isaria fumosorosea Wize (Hypocreales: Clavicipitaceae) play a major role in reducing the population of these invasives. The most insidious spread of these species in India is likely mediated by humans through the movement of infested seedlings and plant materials. Extensive surveys revealed that these species spread rapidly in the large geographical region of India mostly through transportation of infested seedlings. This study reports a major expansion of the geographic and host range and the patterns of co-occurrence, damage and economic impact of these exotic species in India and their natural enemies.

Infestation of the highly invasive whitefly Aleurotrachelus atratus Hempel (Hemiptera: Aleyrodidae) is reported for the first time from India as well as from the Oriental region. The pest was found colonizing coconut palm, Cocos nucifera (Arecaceae) and ornamental areca palm, Dypsea lutescens (Arecaceae) in Mandya and Mysore districts of Karnataka during February, 2019. Whitefly specimens were collected from infested palm plants and the identity of the species is confirmed by morphological characteristics. No parasitisation was observed but four species of predators viz., Dichochrysa astur (Neuroptera: Chrysopidae), Cybochephalus spp. (Coleoptera: Nitidulidae), Chilocorus nigrita and Jauravia pallidula (Coleoptera: Coccinellidae) were found feeding on this invasive species. The severity of the infestations and its impact on coconut as well as other crop plants in India is discussed.

The heartwood borer Aristobia octofasciculata Aurivillius and red stem borer Zeuzera coffeae Nietner were found more prevalent infesting sandalwood in natural forest areas of Karnataka. In the sandalwood plantations, Z. coffeae was the major stem borer distributed in all the districts of Karnataka while the infestation of stem borer Purpuricenus sanguinolentus was prevalent in Bangalore rural district. In addition, two cerambycid beetles, viz. Ceresium gracile (Perroud) and Stenodryas nigromaculatus (Gardner), were found infesting sandalwood for the first time. The host plant of C. gracile is so far unknown and S. nigromaculatus is so far reported on Albizzia procera from India. The impact of infestation of these stem borers on the economy of cultivation of Indian sandalwood is discussed.

Considerable interest has been developed on environmentally friendly technologies for wood protection. The current investigation focused on the development of an ecofriendly wood preservative formulation from coconut shell pyrolytic oil distillate (CSPOD). Rubberwood specimens treated with CSPOD were exposed to brown rot and white rot fungi and the efficacy was assessed in terms of percentage weight loss and FTIR spectra analysis. Treated samples showed significant reduction in weight loss when compared to control samples indicating the efficacy of the distillate. FTIR spectra further confirmed the ability of the distillate to protect wood against decay fungi. Phenolic compounds were the main components in the distillate as evidenced by GC–MS analysis. The presence of phenolic compounds in the distillate has given the significant decay resistance to the treated wood against both white rot and brown rot fungi. Hence, coconut shell pyrolytic oil distillate has the potential to be developed into a wood preservative formulation.

The invasion and infestation of the Rugose spiraling whitefly (RSW), Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) on coconut palm (Cocos nucifera L.) (Arecales: Arecaceae) in India is reported for the first time from Indian as well as from Oriental region. The severity of its infestations and impact on coconut cultivation in India is discussed.

Spatial distribution, abundance and assemblage of termites depend mainly on the local conditions and habitats in which they thrive. Striking differences are observed in the species richness, number of clades and functional diversity of termite assemblage between different habitats. This study aim was to examine effect of human interference in the diversity of wood destroying termite in forest areas as well as managed and unmanaged plantations in South India. Termites attacking trees and wooden logs were collected from forest areas, managed plantations and unmanaged plantations. The termites collected were identified and compared for species abundance, richness and species diversity. Results show that the species composition and species diversity of the wood destroying termites vary according to the conditions. The species diversity measures revealed that there is a significance variation among the forest fauna and plantations. The forest areas have the highest species composition compared to plantations. Species richness is high forest areas. Even though the abundance of termites are more in unmanaged plantations, there is no significant difference related to species diversity among the managed and unmanaged plantations.

This paper provides a user friendly pictorial guide for the identification of 15 wood destroying termites of south India with distinct characters and routes. The species included in the key are Coptotermesheimi (Wasmann), Heterotermes malabaricus Snyder, Microcerotermes flecheri Holmgren and Holmgren, Microtermes obesi Holmgren, Odontotermes assmuthi Holmgren, O. bellahunisensis Holmgren and Holmgren, O. bhagwatii Chatterjee and Thakur, O. bruneus (Hagen), O. ceylonicus (Wasmann), O. feae (Wasmann), O. horni (Wasmann), O. obesus (Rambur), O. redemanni (Wasmann), O. wallonensis (Wasmann) and Nasutitermes sp.

A study was conducted to investigate the population dynamics of four important coccids viz., Aonidiella orientalis (Newstead), Ceroplastes actiniformis Green, Cardiococcus bivalvata (Green) and Parasaissetia nigra (Nietner) infesting sandal in Bangalore, India. Meteorological data viz., monthly mean maximum and minimum temperatures, morning and evening relative humidity and total rainfall were also collected during the experimental period for statistical analysis to ascertain their influence on the population of coccids. The results show that all the four coccids are infesting sandal throughout the year. Maximum temperature exhibited significantly negative correlation with the population dynamics of A. orientalis, while other weather parameters did not show much influence on its incidence. In case of C. bivalvata, minimum temperature and morning relative humidity exhibited significant positive correlation with its population dynamics while other weather parameters had less significant effect on its population dynamics. For C. actiniformis and P. nigra, none of the weather factors seem to have influence on their incidences.

Investigations were carried out to determine the natural resistance of 20 commercially available imported timber species and two Indian timber species against wood decay fungi. Based on the resistance against the wood decay fungi, Fagus grandifolia Ehrh. F. sylvatica L., Acer pseudoplatanus L., and Hevea brasiliensis Muell. Arg. with weight loss of around 40–50 % comes under “non-resistance class”. Decay was around 30 % in Fraxinus angustifolia Vahl., F. excelsior Quctnon. and Michelia champaka L. which come under “moderately resistance class”. Dryobalanops aromatica Geratin., Pterocarpus soyauxii Taub. (from two countries), Quercus robur L., Shorea laevis Ridl., S. marcoptera Dyer., S. robusta Gearth., Tectona grandis L.f. (from five countries) and Xylia dolabriformis Benth. showed less than 10 % of weight loss and can be grouped under “high resistance class”.

The influence of biochemical parameters of the host plants viz.Jasminum multiflorum Andr.,Jasminum sambac Ait.,Jasminum grandiflorum Linn.,Jasminum auriculatum Vahl.,Jasminum pubescens Willd. andJasminum flexile Vahl. on the biology of Dialeurodes vulgaris was studied. The results indicate remarkable variation in the biochemical parameters of host plants which affected significantly the biology of the insect. The per cent survival and growth index have been considerably low inJasminum pubescens, Jasminum auriculatum andJasminum grandiflorum and the same trend has been noticed with regard to fecundity and longevity also. The most preferred hosts have beenJasminum sambac andJasminum multiflorum. It is observed that high amount of phenol and excessive accumulation of sugars in host plants make them nonpreferred while high amount of amino acids makes the plants more preferred byDialeurodes vulgaris.

The present study aims to understand the influence of biochemical parameters of the host plants vizAbelmoschus esculentus L.,Gossypium hirsutum L. andAbutilon indicum G. Den. on the reproductive biology ofEarias vittella. The results indicate remarkable variation in the biochemical parameters of host plants which affected significantly the growth index and reproductive potential of the insect species. Decrease in body weight, fecundity, prolongation of larval period, percentage of larva becoming adult and adult longevity of both male and female was observed when reared onAbutilon indicum which had less amount of reducing sugars, protein and free amino acids but had high amount of non reducing sugars. Decreased larval period, increased fecundity and adult longevity were observed when reared on cotton and okra which had high amount of reducing sugars, free amino acids and protein. There was no significant difference in the amount of total soluble sugars among the 3 hosts tested. The growth index and fecundity ofEarias vittella are apparently high on okra than on cotton. It is observed that high amount of reducing sugars, free amino acids and protein seems to be favourable for increase in fecundity ofEarias vittella.