The nutritive value of five edible aquatic insects of Assam—Hemipterans; water bug (Diplonychus rusticus Fabricius) family belostomatidae; giant water bug (Lethocerus indicus Lepeletier and Serville) family belostomatidae; water scorpion (Laccotrephes sp.) family nepidae, water stick (Ranatra sp.) family nepidae; Coleopterans diving beetle (Cybister sp.) family dytiscidae—based on their proximate and elemental composition, antioxidant and antinutritional properties were assessed by using standard methods of analysis. Analytical studies revealed that the selected aquatic insect species have high nutritive value and are rich sources of protein (50.03 to 57.67%) and other nutrients (fat, carbohydrate and crude fiber, etc.) along with superior energy contents (331.98 to 506.38 kJ/100 g). The aquatic insect species also contained appreciable amounts of major and trace dietary elements. Phenol and flavonoid contents reflect its high antioxidant activity (80.82 to 91.47% DPPH inhibition). Tannin (18.50 to 60.76 mg tannic acid equivalent/100 g), phytic acid (11.72 to 97.30 mg/100 g) and oxalic acid (2.93 to 5.34 mg/100 g) as antinutritional compounds were registered below the toxic level (0.52% or 520 mg/100 g). The present findings indicate that the selected aquatic insect species can be considered as ideal candidates for exploration as food and feed to ensure nutritional and livelihood security of this region.

Land use change has a great impact in determining the diversity patterns of soil fauna. Adoption of any land use pattern significantly affects the soil structure and its physico-chemical characteristics, which often leads to the loss of biodiversity. Considering the collembolans as the key organism in the indicator shopping basket of soil environment, the response of Collembola communities under three different land uses represented by forest, vegetable and tea ecosystems was studied. Collembolans were sampled at monthly intervals using Tullgren funnel and identified by standard taxonomic keys. Diversity analysis and soil chemo-edaphic factors were studied to establish the impact of different land uses on Collembola communities. Five genera of Collembola viz., Cyphoderus, Entomobrya, Isotoma, Folsomia and Hypogastrura were recorded from the forest ecosystem whereas Folsomia was completely absent in vegetable ecosystem and the tea ecosystem soil was devoid of both Folsomia and Hypogastrura. Seasonal diversity and density of Collembola were recorded to be higher in the forest ecosystem indicating the presence of relatively stable habitats as compared to vegetable and tea ecosystems showing relatively disturbed habitats. Correlation studies between different chemo-edaphic factors and collembolan population revealed that the moisture and organic carbon content of soil had significant positive correlation during all the four seasons in all the ecosystems studied. Higher adoption of mechanical and chemo-centric agriculture depletes the available resources of the soil and makes it less habitable and conducive for the growth and sustenance of collembolans in vegetable and tea ecosystem as compared to forest. Appropriate landscape planning, land management strategies and developing proper methods of land use practices may pave the way for the improvement of collembolan diversity at landscape level.

Aim: To investigate the influence of soil physico-chemical properties on diversity and density of Collembola in an undisturbed fallow land ecosystem. Methodology: Soil sampling was done at monthly intervals to explore the diversity, density and seasonal variation patterns of collembolan population in a fallow land ecosystem during March, 2015 to February, 2016. Collembolans were sampled using Tullgren funnel and identified by standard taxonomic keys. Finally, correlation studies were conducted to assess the influence of different soil physico-chemical properties on diversity and density of collembolans. Results: Five species of Collembola (Cyphoderus sp., Entomobrya sp., Isotoma sp., Folsomia sp. and Hypogastrura sp.) belonging to 4 families (Cyphoderidae, Entomobryidae, Isotomidae and Hypogastruridae) were identified. Cyphoderus sp. was recorded to be the most abundant species contributing 44.29 percent of population. Analysis of different diversity indices revealed higher diversity of collembolans during summer, indicating the presence of relatively stable habitats as compared to other seasons. Summer season also recorded highest density of Collembola. During all the seasons studied, a strong significant positive correlation (P

An experiment was conducted during the summer season of 2012 and 2013 to investigate the effect of Apis cerana pollination on some qualitative and quantitative parameters of sesamum at Assam Agricultural University, Jorhat, India. Sesamum capsules plant⁻¹, seeds capsule⁻¹, 1000-seed weight, per cent of seed set and germination were found to be higher in Apis cerana pollinated treatments over open pollination and pollinator exclusion. Yield of sesamum crop was also found to be higher in Apis cerana pollinated treatments over open pollination and pollinator exclusion. The highest seed yield (835 kg ha⁻¹) was recorded from Apis cerana pollination @ 7 hives per hectare which was at par with Apis cerana pollination @ 5 hives per hectare having 810 kg ha⁻¹. The per cent oil and moisture content of Apis cerana pollinated seeds of sesamum were also found to be significantly higher over open pollination and pollinator exclusion treatments. The highest per cent of oil (54.17%) and moisture (10.18%) content were recorded from Apis cerana pollination @ 7 hives per hectare.

The diversity of insect foragers and foraging behaviour of Apis cerana on Sesamum indicum were recorded, amongst foragers Apis cerana was the most dominant forager (32.66%) followed by Apis dorsata (26.54%), Xylocopa fenestrata (7.48%), Vespa cincta (6.12%), Coccinella septempunctata (6.12%), Musca domestica (6.12%), Apis florea (4.76%) and Xylocopa leucothorax (4.08%). Besides these, other insect foragers found in less numbers were Chalicodoma cephalotes (2.04%), Episyrphous belteatus (2.04%), Pieris rapae (2.04%). The study on foraging behaviour of Apis cerana revealed that 0900-1000 hours was the peak period of visit on sesamum flower. The number of Apis cerana per square meter per minute was recorded to be maximum (9.75 ± 0.15) during 0900-1000 hours and minimum (0.75 ± 0.19) during 1600–1700 hours. The number of flowers visited per minute was maximum (11.65 ± 0.15) in between 0500-0600 hours and minimum 4.12 ± 0.11 per minute at 1600–1700 hours of the day. The maximum time spent per flower was recorded to be 6.83 ± 0.10 seconds during 0900-1000 hours and minimum being 3.87 ± 0.06 seconds during 1600–1700 hours of the day. Maximum pollen load was found to be 8.34 ± 0.14 mg during 0900-1000 hours while minimum to be 2.31 ± 0.08 mg during 1500–1600 hours of the day. Bright sunshine hours and temperature showed positive correlation whereas rainfall and relative humidity showed negative correlation with foraging behaviour of Apis cerana.

Field experiments were conducted at Charaibahi village, Jorhat, Assam during 2015-17 to evaluate six ecofriendly IPM modules against red ants Dorylus orientalis Westwood in potato. Among the modules evaluated, Module-II (pre sowing treatment of mustard oil cake @ 150 kg/ ha+ wood ash 150 kg/ ha+ panchagavya @ 3% and soil drenching with neem oil @ 5 ml/ lit after 1^st and 2^nd earthing up (25 and 60 DAS) recorded the lowest tuber damage both in weight (8.65%) and number (10.70%) basis and found at par with the recommended package of practices (RPP) (application of malathion 5% dust @ 40 kg/ ha+ mustard oil cake @ 150 kg/ ha in the soil after 1^st and 2^nd earthing up) recording 8.18 and 10.20% tuber damage, respectively. The same module also recorded highest tuber yield (119.37 q/ ha) which was at par with the RPP (120.12 q/ ha). The maximum benefit cost ratio (1.41) was recorded in RPP followed by Module-II (1.33) and Module-VI (1.26). The untreated control plot registered a very high level of tuber damage (25.93 and 28.70 on weight and number basis, respectively) having maximum population of red ants (3.95 numbers/ m² ) with a tuber yield of 89.91 q/ ha.