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A new emergence trap was fabricated for collecting saproxylic insects from precise areas of dead and fallen trees. The trap works on the principle of all emergence traps, i.e., organisms emerging from a substrate get attracted towards light, where they encounter a transparent surface and get collected in a collecting tube with preservative fluid. It is one of the most objective methods for sampling saproxylic insects as they emerge from wood substrata. Using many replicates of this trap, the entire heterogeneity of a substratum like dead wood can be easily covered. The trap can provide a higher definition of the sampling area and be used for studying assemblages of saproxylic insects. It is almost costeffective and user-friendly under field conditions, on logs and snags, and even on live trees. In this study, 102 such field emergence traps were deployed in a conserved area, and 59 species of saproxylic insects belonging to 5 functional groups were collected during a brief sampling period of 3 months. Extensive sampling trials using such traps in more numbers for extended periods can provide insights into species’ diversity and host preferences. [ABSTRACT FROM AUTHOR]

Successful exploitation of fungi as biocontrol agents depends on the ability to produce high concentrations of quality inoculum at reasonable costs. Metarhizium anisopliae is the most exploited entomopathogen for biocontrol, as it is well known for its high virulence against a variety of insect pests. In the present study, the suitability of various grains, agro-wastes, and other naturally available solid media was evaluated for mass production of three M. anisopliae isolates, MIS2, MIS7, and MIS13. Effect of supplementing the growth media with yeast extract, powdered dry silkworm pupae, and mannose on the production of conidia was studied. Among the grains, rice yielded the highest number of conidia, while among agro-wastes, groundnut cake was the best. Among the other substrates, soybean yielded maximum conidia. Spore yields were considerably less on agro-wastes and other substrates when compared to rice. Spore yield on rice was 19.87, 19.02, and 19.62 × 109 conidia/g for isolates MIS2, MIS7, and MIS13, respectively. Augmenting the substrates with dry silkworm pupa powder yielded more conidia than other fortifying substances. Rice + pupa powder combination yielded 21.36, 20.61, and 20.16 × 109 conidia/g for the three isolates, respectively. Supplementing the culture media with dried pupa powder during sub-culturing and storage enhanced the virulence and prolonged the viability of the entomopathogen isolates. This technique of adding silkworm pupa powder is an innovative and first time attempt to exploit a nutrient-rich insect product, available in plenty as an underutilized byproduct of sericulture industry. [ABSTRACT FROM AUTHOR]

A survey of butterfly fauna was conducted in the study area comprising of Kudremukh National Park and Mookambika and Someshwara Wildlife Sanctuaries in Central Western Ghats of Karnataka. The study on the distribution and relative abundance of butterflies occurring in these areas was conducted through random sampling. Butterfly sample plots were laid in five different forest types, namely, evergreen, semi-evergreen, shola forests, open forest, and misc. plantation. Sampling was done by Blair and Launer (1997) method. Sample plots were of size 100 m×200 m. Transects were traversed on a monthly basis for counting of butterflies for a period of 2 years. The numbers of butterflies sighted in each sample plot were recorded separately for each family. The total number of butterflies sighted in each month was calculated. Out of the reported 149 species of butterflies in the region, a total of 142 species belonging to the five families were sighted during the study. For comparing the trends in the butterfly population, Shannon diversity index (H) and Margalef's richness index were calculated. Density of butterfly species in each sample plot was calculated. The values of H were then grouped according to the three different seasons. Of the five families of butterflies in the study area, Nymphalidae were found to be dominating in all the seasons. Species belonging to Hesperiidae were found in least number. The population of all butterfly families peaked during the month of September in both the years. However, in the year 2003-2004 in semi-evergreen forest, the peak was observed in the month of August. In the year 2004-2005, evergreen and miscellaneous plantation plots recorded the highest numbers in the month of October. There was a second peak during March/April. The lowest population was reported during spring, i.e. February/March. The increase in number of butterflies is due to the favorable conditions for breeding in the post-monsoon months when plenty of fresh flush of leaves are available. This is followed by flowering season of several plants which provide a nectar source for adult butterflies. Similar conditions prevail in the months of March/April too favoring a second peak. Significant fluctuations in butterfly population with change of seasons across forest types were observed. [ABSTRACT FROM AUTHOR]

Mangrove forests, the sentinels of the seashores, contribute highly to the ecological and economic security of mankind. Insects living in mangrove trees play diverse roles and assist in many ecosystem processes, among which their role as pollinators is the most noteworthy. Attempts were made to bring out the fascinating interrelationships between plants and insects as partners in the reproductive success of this ecosystem. Insects associated with pollination of three selected major mangrove plants in the coastal tracts of Karnataka were documented. Twenty-three species of insects belonging to 15 families of four major orders were documented from the flowers of Avicennia officinalis L. Eleven species were observed on Rhizophora mucronata L. and eight species on Sonneratia caseolaris (L.) Engler. Floral morphology, flowering season, different floral phenomena, and pollination biology were studied through various field experiments. A. officinalis starts flowering in mid-late April and continues till the middle of August. The flowering period of R. mucronata was found to stretch over a period of February to July in coastal Karnataka. S. caseolaris was found to start flowering in the month of October and the flowering season was found to last up to the month of May. The study revealed that S. caseolaris and A. officinalis offer both nectar and pollen to the visitors. However, in the case of R. mucronata no nectar was found to be produced by the flower. Profuse amount of pollen was produced as a reward in this species. Reproductive biological experiments revealed that A. officinalis can reproduce through both cross-pollination and self-pollination, with preference for cross-pollination. Field pollination biology experiments in R. mucronata clearly showed its self-pollination mode. Insect exclusion resulted in very less fruit set in S. caseolaris, the maximum being only 5%, which indicated the predominance of cross-pollination in the case of this species. This study show cases the mutual benefits of the diversity of insects and plants in the sustenance of the mangrove ecosystem. [ABSTRACT FROM AUTHOR]

Mangrove is a highly resilient ecosystem unique in harboring a diverse group of plants and animals with extreme salt tolerance capacity. In Indian scenario, 4461 km² area is under mangrove cover, amounting to 5% of the world's mangrove area. Coringa mangrove is situated in East Godavari district of Andhra Pradesh state in the east coast of India. Vast floral diversity of this mangrove supports large entomofaunal diversity. Damage of leaf photosynthetic area due to insect feeding is a major problem in this mangrove ecosystem. The present research focused on quantification of the damage of mangrove leaves due to insect feeding and measuring the extent of insect folivory between three species of Avicennia, a major floral component of Coringa mangrove. This study involved the application of a software-based digital image analysis to quantify the magnitude of insect defoliation. Three species of Avicennia, namely, Avicennia officinalis, Avicennia marina, and Avicennia alba were selected as target species due to their abundance in good numbers. The digital image of the collected leaf samples was created using desktop scanner, and the same was subjected to analysis. The result showed an overall range of 0.15-20.42% leaf area damage due to insect folivory in three species of Avicennia in two maturational stages of leaves, namely, young and matured leaves. The analysis showed significant variation in the magnitude of insect folivory in 2009, when compared between three species of Avicennia in the case of both young and matured leaves. However, in 2010, though in the case of young leaf samples, there is no significant variation in leaf area damage between three species; the matured leaves showed clear cut variation in damage extent. [ABSTRACT FROM AUTHOR]

The durability of bamboo depends on many factors like the species, edaphic conditions of its growth and also the position of the culm. Bambusa bamboos and Dendrocalamus strictus are the most commonly grown important commercial bamboo of South India. Experiments were conducted to investigate the durability of B. bamboos and D. strictus of these 2 species collected from the dry and wet zones in Karnataka. Durability against termites was tested as per IS: 4833-1968 at the termite test yard at Nallal test yard and observations were taken for a period of 36 months. The 36 month observation indicates that B. bamboos and D. strictus collected from the dry zone were more resistant to termites. The durability test against fungi was conducted as per standard under laboratory conditions by using the white rot and brown rot fungus. The results revealed that in D. strictus, culms of wet zone are more durable when compared to culms of dry zone, and in case of B. bamboos, dry zone culms are more durable than those of the wet zone. However, the length wise durability of selected bamboos against termites and fungi followed a fixed pattern where the bottom portion of culm showing more durable followed by the middle and the top portion. [ABSTRACT FROM AUTHOR]

Dendrocalamus brandisii (Munro.) is one of the economically important bamboo species, the culms of which are used for building house, baskets and decorative articles. The edible young shoots are used in food items. The germination percentage is reduced due to the problem of fungal infection in seed stages which can further cause diseases in the nurseries and sometimes at plantation stages. Adopting standard techniques, fungal species associated with the seeds were evaluated. Total 38 species of seed borne fungi were encountered, of them the major species were Alternaria, Aspergillus, Chaetomium, Colletotrichum, Cladosporium, Curvularia, Fusarium, Mucor, Penicillium and Rhizopus along with few non-sporulating fungi. Of the total isolates, species of Alternaria were the common fungal isolates in both blotters and agar plate techniques. Agar plate method showed more fungi than blotter method. In vitro control studies were conducted by disinfecting the seeds using fungicides (0.12% of Dithane M-45, Captaf, Blitox, Bavistin and Emisan) and leaf and bark extracts of Prosopis juliflora (0.1, 0.5 and 1%). Dithane M-45 and Captaf were most effective and 1% leaf extract of P. juliflora showed complete inhibition of seed borne fungi. [ABSTRACT FROM AUTHOR]

Paliga machoeralis is the most malicious pest of teak responsible for epidemic defoliation of trees in plantations and natural forests. Metarhizium spp. have been a long standing model for biological control reported to have great potential for the management of over 200 insect species. The present study was conducted to evaluate the virulence of M. anisopliae isolates against P. machoeralis in the laboratory. Bioassay of 25 isolates of M. anisopliae was carried out using inoculum concentrations ranging from 10³-108 conidia ml-1. The dose-mortality and time-dose-mortality responses for these isolates were determined. Median lethal dose concentration (LC50) values of isolates ranged from 0.11 x 105 to 3417.65 x 105 conidia ml-1. Among the 25 isolates, MIS2, MIS7, MIS1 and MIS3 were found to be more effective with lower LC50 values. MIS2 was the most effective isolate with lowest LC50 (0.11 x 105 conidia ml-1) followed by MIS7 (0.15 x 105 conidia ml-1). Lowest median lethal time (LT50) of 3.4 days was also recorded for MIS2 followed by MIS7 (3.7 days), MIS1 (4.3 days) and MIS3 (4.9 days) at spore load of 107 conidia ml-1. With respect to LC50 and LT50, MIS2 proved to be superior over other isolates. The results indicate prospects of isolates MIS2 and MIS7 in developing biopesticide formulation for management of teak skeletoniser [ABSTRACT FROM AUTHOR]

Teak (Tectona grandis) is one of the most favoured timbers in the world and is used for many products and services. In north Canara Circle of Karnataka, India the heartwood borer, Alcterogystia cadambae, is found to cause substantial damage to teak trees. From morphometric estimations of larvae collected in the field, and by applying Dyar's law, it was ascertained that there were seven stages of instars. The laboratory rearing using artificial diet also revealed that larvae moulted six times to have seven instars in its larval life. The duration of the first to seventh instar was 32.2, 13.0, 38.0, 31.0, 30.5, 33.0 and 43.0 days respectively. The total larval duration was 207 days. [ABSTRACT FROM AUTHOR]