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.

Mitigation of greenhouse gases (GHGs), improving nutrient-use efficiency (NUE), and maximizing yield in rainfed lowland rice cultivation poses significant challenges. To address this, a two-year field experiment (2020 and 2021) was conducted in Assam, India, to examine the impact of different fertilizer-management practices on grain yield, NUE, and GHGs in wet direct-seeded rice (Wet-DSR) during the kharif season. The experiment included eight treatments: control; farmer’s practice (30-18.4-36 kg N-P₂O₅-K₂O ha⁻¹); state recommended dose of fertilizer (RDF) @ 60-20-40 kg N-P₂O₅-K₂O ha⁻¹ with N applied in three splits @ 30-15-15 kg ha⁻¹ as basal, at active tillering (AT), and panicle initiation (PI); best fertilizer management practices (BMPs): 60-20-40 kg N-P₂O₅-K₂O ha⁻¹ with N applied in three equal splits as basal, at AT, and PI; and fertilizer deep placement (FDP) of 120%, 100%, 80%, and 60% N combined with 100% PK of RDF. The experiment was arranged out in a randomized complete block design with three replications for each treatment. The highest grain yield (4933 kg ha⁻¹) and straw yield (6520 kg ha⁻¹) were achieved with the deep placement of 120% N + 100% PK of RDF. FDP with 80% N + 100% PK reduced 38% N₂O emissions compared to AAU’s RDF and BMPs, where fertilizer was broadcasted. This is mainly due to the lower dose of nitrogen fertilizer and the application of fertilizer in a reduced zone of soil. When considering both productivity and environmental impact, applying 80% N with 100% PK through FDP was identified as the most effective practice.