Sustainability and climate change are the two major challenges to the agricultural production system. The trade-off between them is essential for higher profitability. The energy assessment is essential for judging the sustainability and vulnerability of a production system. Besides, nutrient management and weed management are equally imperative to sustainability. Thus, the present study was executed to assess the energy balance, key energy indicators and profitability of rice–maize–green gram system under different nutrient and weed management practices. Application of Brassicaceous seed meal (BSM) along with mineral fertilizer attributed the highest rice (5.62 t ha⁻¹) and maize (6.48 t ha⁻¹) yield which was 11.6%, 8.3% and 3.7% in maize and 10.0%, 6.2% and 8.7% in rice for the conjoint application with vermicompost, farmyard manure (FYM) and neem cake, respectively. Moreover, BSM recorded the highest net energy gain, energy use efficiency and energy efficiency ratio and the lowest specific energy in all the crops. Application of pre-emergence herbicides followed by hoeing was found to be best in all respects including yield, profitability, energy use efficiency, energy effectiveness, etc. The appropriate combination of integrated nutrient management with BSM and pre-emergence herbicide application followed by hoeing provided an additional advantage not only in terms of yield but also an efficient use of energy, profitability and environmental safety. BSM and neem cake could be the alternative organic manure in the integrated nutrient-cum-weed management module and they could be able to compensate the paucity of FYM and vermicompost in the country.

A field experiment was conducted at Pundibari, Cooch Behar in West Bengal during 2003-05 to study the re- sponse of ramie [Boehmeria nivea (L.) Gaud.] cultivars ('R 141 1 ' and ' R 67-34') to different planting methods (ridge and flat-bed methods) and nutrient management [I00 and 150% NPK supplied through chemical fertilizer, 50% N with 100% PK from chemical fertilizer + 50% N through ramie waste (1,339 kglha), and 50% N with 100% PK from chemical fertilizer + 50% N through vermicompost (828 kglha)]. Based on four cuttings, ramie cultivar 'R 141 1' recorded higher fibre yield and net income under ridge-bed planting when supplied with 150% NPK through chemical fertilizer, which was on a par with that of 50% N with 100% PK from chemical fertilizer + 50% N through ramie waste. Integrated use of chemical fertilizer and ramie waste improved the pH and NPK status of the soil. 'R 141 1' proved suitable with either sole application of 150% NPK of chemical fertilizer or combined use of chemical fertilizer and ramie waste under ridge-bed planting method to get optimum yield.

Appraisal has been made at the fodder farm of ICAR-IVRI, Izatnagar campus by following standard procedure adopted by AICRP on Weed Management (ICAR) during 2015 and 2016. Results revealed that Trianthema portulacastrum and Trianthema monogyna were widely distributed in the fodder farm during summer and rainy seasons. It produced flower continuously up to second fortnight of November with 224 to 504 seeds/plant and multiplied both by seeds (More than 80% germination of current seeds) and fragmented plant parts. Another broad-leaved weed Celosia argentea preferred the growing condition of fodder sorghum and it produced 1, 716 to 3, 496 seeds/plant. The broadleaved weed Coccinia grandis was associated with fodder maize and sorghum, and produced 2, 934 to 4, 428 seeds/plant. Numerous seed production capacity of these weeds supported its high profile emergence. Among the other weeds the grasses were widely distributed, whereas the sedges were appeared in patches. Three major broad-leaved weeds Coronopus didymus, Rumex dentatus and Cichorium intybus appeared during 1^st, 2^nd, 3^rd and 4^th cutting of berseem during winter season, respectively. The weeds Trianthema portulacastrum, Trianthema monogyna, Coccina grandis, Rumex dentatus and Cleome viscosa had shown the character of endozoochory dissemination. Uniform distribution of rainfall during 2015 caused rapid infestation of broad-leaved weeds (Trianthema sp., Coccinia grandis, Celosia argentea) whereas huge down pour within short period during monsoon season of 2016 caused submergence which, in turn, reduced infestation of broad-leaved weeds and side by side increased invasion of grasses. Mixed cropping of fodder maize (Variety ‘African Tall’) and fodder cowpea (Variety ‘Bundel Lobia 2’) controlled Trianthema sp. and maximum green fodder yield was obtained at 55 days after sowing beyond that cowpea showed competitive effect on maize. Turning the land from fodder sorghum to cowpea minimised distribution and seed production capacity of Celosia argentea. Mixed cropping of berseem (Variety ‘Wardan’) + gobhi sarson (Brassica napus var. napus) and berseem (Variety ‘Wardan’) + rye grass (Variety ‘Makkhan Grass’) reduced infestation of Coronopus didymus. Growing of dual purpose (grain-cum-green fodder) wheat variety ‘VL Gehun 829’ reduced infestation of resistant biotype of Phalaris minor.

A field experiment was carried out during winter (Rabi) seasons of 2012–13 and 2013–14 at research farm of Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal with the objectives to study the weed control practices in no-tilled dibbling maize within rice residues. The experiment consisted of eight treatments, comprising of varying doses of 2, 4-D (post-emergence treatment), atrazine with sequential application as pre-emergence and post-emergence treatment, pendimethalin followed by atrazine, weedy check and complete weed-free treatments, laid out in randomised block design (RBD) with four replications. Highest weed control efficiency and lowest weed index values were registered by atrazine 1.0 kg/ha as pre-emergence + atrazine 1.1 kg/ha as post-emergence. The dominant weed flora were the broad-leaved weeds Polygonum persicaria, P. pensylvanicum, P. orientale, and the grasses Digitaria ciliaris, Setaria glauca. Among the weed control practices, season long weed free condition recorded the highest grain/kernel yield of maize (9.52 and 10.6 t/ha) during both the years, which was statistically at par with atrazine 1.0 kg/ha as pre-emergence + atrazine 1.1 kg/ha as post-emergence (9.3 and 10.4 t/ha) and atrazine 0.75 kg/ha as pre-emergence + atrazine 1.1 kg/ha as post-emergence (9.07 and 10.12 t/ha). The atrazine 1.0 kg/ha as pre-emergence + atrazine 1.1 kg/ha as post-emergence gave maximum net return of (` 93, 650/ha and ` 1, 21, 050/ha) and maximum net return per rupee invested (1.88 and 2.31).

The effectiveness of endozoochory and germination success of the weeds after passage through the animal gut are the important traits for dissemination and invasion of weeds. With this view, experiments were conducted during the Rabi season of 2017–18 and 2018–19 at ICAR-Indian Veterinary Research Institute (IVRI), Izatnagar Campus with the objective to assess the effect of endozoochorous dissemination of weed (Rumex dentatus) on late sown wheat productivity (Variety HD 3059) while using cattle shed water for irrigation. The results revealed that late harvesting of the berseem led to the development of R. dentatus up to seeding stage. Berseem green fodder contaminated with seeds of R. dentatus was fed to the cattle and buffaloes. Application of carfentrazone at 25 days after sowing (DAS) reduced the population of existing broad-leaved weeds, however, use of cattle shed water for irrigation increased the population of R. dentatus from 35 DAS up to 17% at 50 DAS, 134% at 65 DAS and 186% at 80 DAS. Whereas, the adjacent plot irrigated with normal ground water, recorded the declining trend of R. dentatus population from 35 DAS i.e. up to 15, 32 and 50% reduction at 50, 65 and 80 DAS, respectively. Large infestation of R. dentatus due to use of cattle shed water contaminated with seeds of R. dentatus reduced wheat productivity up to 44% (2.14 t/ha) as compared to the grain yield 3.82 t/ha obtained from the plot irrigated with normal ground water. During second year, the entire field was irrigated with normal ground water and similarly carfentrazone was used at 25 DAS. These measures reduced the population of R. dentatus and weed showed declining trend up to 30, 71 and 79% reduction at 50, 65 and 80 DAS from 35 DAS. These results confirmed that R. dentatus has the endozoochorous mechanism of its dissemination and use of cattle shed water for irrigation may not be recommended if the berseem fodder is infested with seeds of R. dentatus.