Chlorophyll has direct roles on photosynthesis and hence closely relates to capacity for photosynthesis, development and yield of crops. With object to explore the roles of chlorophyll content and its relation with other yield attributing traits a field research was conducted using fourteen early genotypes of maize in RCBD design with three replications. Observations were made for Soil Plant Analysis Development (SPAD) reading, ear weight, number of kernel row/ear, number of kernel/row, five hundred kernel weight and grain yield/hectare and these traits were analyzed using Analysis of Variance (ANOVA) and correlation coefficient analysis. SPAD reading showed a non-significant variation among the genotypes while it revealed significant correlation with no. of kernel/row, grain yield/hectare and highly significant correlation with no. of kernel row/ear and ear weight which are the most yield determinative traits. For the trait grain yield/ha followed by number of kernel row/ear genotype ARUN-1EV has been found comparatively superior to ARUN-2 (standard check). Grain Yield/hectare was highly heritable (>0.6) while no. of kernel / row, SPAD reading, ear weight, number of kernel row/ear were moderately heritable (0.3-0.6). Correlation analysis and ANOVA revealed ARUN-1EV, comparatively superior to ARUN-2(standard check), had higher SPAD reading than mean SPAD reading with significant correlation with no. of kernel/row, no. of kernel row/ear, ear weight and grain yield/ha which are all yield determinative traits . This showed positive and significant effect of chlorophyll content in grain yield of the maize.

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.

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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.