Journal of Research in Weed Science

Abstract A field experiment was conducted in pre-monsoon season during 2017 and 2018 at National oil seed research program, Nawalpur, Sarlahi, Nepal, to study the impact of weed management practices in groundnut production. Pendimethalin as pre-emergence, while Metribuzin, Propaquizafop at 100 g per hectare, Quizalofop ethyl at 100 g per hectare, as post emergence was used along with integration with hand weeding and intercultural operation. The result revealed that supplement of the hand weeding after the application of the pre-emergence herbicides pendimethalin was found effective in  reducing  the weed severity and improves the growth and yield attributes and ultimately yielded 2101 kg ha^‑1. This treatment also recorded the highest gross and net return (NRs 168080 and 48470) and benefit cost ratio (1.4) thus, this integrated weed management practice could become effective and economic under southern belt terai agro climatic condition of Nepal.

Abstract The experiment was conducted in farmer field with farmer managed in Randomized Complete Block Design (RCBD) with three treatments and seven replications. The treatments were weed management practices including (i) Farmer’s Practice (FP) (ii) Two manual weeding (iii) First manual weeding and 2nd weeding by post emergence herbicides (Temboterine and Atrazine) application in Inner-terai, Dang, Nepal. Results showed that first manual weeding and 2nd weeding by herbicides significantly reduced weed infestation and gave higher maize grain yield. The yield attributes were cob length, total number of grain, number of grain per row, cob weight with husk and cob weight without husk. Thus, herbicides used after 1^st manual weeding is successful for high maize yield.

Abstract An experiment was conducted in IAAS, Lamjung research field in 2017 in spring Maize with split plot design to evaluate the effect of weed management practice and tillage system on productivity of spring maize. In tillage system, no-till and conventional tillage were kept as main factor whereas seven weed management practices (viz. sequential application of atrazine at 0.75 kg a.i. ha-1 and 2,4-D at 1.5 kg ha-1; pre-emergence tank mix application of atrazine at 0.75 kg ha-1 and glyphosate at 2.5ml lit-1 of water; pre-emergence tank mix application of atrazine at 0.75 kg ha-1 and pendimethalin at 2ml lit-1 of water; cowpea co-culture; black polythene mulch with control treatment weed free and weedy check as sub-plot. Tillage method had not significant effect on the weed dry matter accumulation in different stages. However, weed dry matter accumulation was varied with different weed management practices. The weed check plot was of highest dry matter accumulation (273.38g m-2, 361.95 g m-2 and 235.95 g m-2 in three different stages (30, 60 and 90 DAS respectively). The highest grain, straw yield and yield attributes was found in plastic mulch plot and no-till system with less severe to weed infestation and index which is statically at par with intercropping with cowpea. Though none of weed management practices completely eliminated weeds, black polythene mulching resulted in best grain yield. Besides the environmental protection, cowpea co-culture treatments yielded almost similar grain yield as compared with common herbicidal weed management practices.

Abstract Sustainable agriculture requires the use of environmentally friendly management practices. Mulching is one of the most effective methods that can play a positive role in weed management, improving soil properties as well as increasing crop production. A field experiment was conducted at the research farm of National Maize Research Program (NMRP), Rampur, Chitwan, Nepal during winter season, 2016. The experiment was carried out in single factor randomized completely block design comprising of nine weed management methods with four replications. Data regarding the weed population, weed dry weight, yield attributes and yield were recorded during the study. Different weed management practices showed significant differences on weed dynamics and weed control efficiencies. Black polythene mulch and silver black mulch was found more effective to reduce total weed density and dry weight during whole crop season and remain comparable with other polythene mulch too. The effect of weed management practices observed on weed density and dry weight were reflected on grain yield. The highest grain yield was recorded in silver black plastic mulch (4537.50 kg ha^-1) followed by black plastic mulch (4068.20 kg ha^-1), clear plastic mulch (4065.22 kg ha^-1), green plastic mulch (3834.84 kg ha^-1) and weed free (3222.74 kg ha^-1) which were comparable to each other. At tasseling-silking stage among plastic mulch treatment, the higher moisture conservation observed on the black plastic mulch followed by clear plastic mulch, green plastic mulch and silver black plastic mulch. While comparing of plastic mulch with dead mulch, moisture on dead mulch remain higher than plastic mulch after 90 DAS. Thus, in humid subtropical region of western Chitwan, Rampur, the maize can be successfully cultivated by using different color of polythene mulch.