An experiment was carried out at farmers' field to compare the effects of live mulches and herbicide on weed growth and dynamics, yield, and economic performance of direct seeded rice under humid sub-tropical condition at Phulbari, Chitwan in 2009. The experiment was conducted in Randomized Complete Block Design with eight treatments and three replications. The treatments consisted of i) control, ii) three hand weeding, iii) herbicide application (bispyribac sodium @ 80 ml/ha) + one hand weeding, iv) wheat straw mulch @ 5t/ha + one hand weeding, v) Eupatorium mulch @ 5t/ha + one hand weeding, vi) brown manuring with Sesbania aculeata @ 30 kg/ha, vii) brown manuring with Sesamum indicum @ 2kg/ha, and viii) brown manuring with Crotolaria juncea @ 30 kg/ha. Weed dry matter accumulation was significantly lower with herbicide application (1.15 g/m 2 ) than wheat straw mulch (6.75 g/m 2 ). The treatments with brown manuring and Eupatorium mulch were found to be equally effective in suppressing the weed growth by reducing both dry matter content and weed density. Application of Eupatorium mulch one day after sowing produced significantly higher grain yield (3.5 t/ha) than control (1.77 t/ha), Sesamum brown manuring (2.97 t/ha) and wheat straw mulch (2.83 t/ha). Yield attributes like effective tillers/m 2 , panicle length and panicle weight were positively correlated with grain yield (r = 0.540, 0.705, 0.531 and 0.613 respectively). The net profit (Rs. 63.17 x 1000/ha) obtained from the treatment with Eupatorium mulch was higher than other tested treatments. Eupatorium mulch and herbicide application recorded equal benefit cost ratio of 2.4. Cultivation of direct seeded rice with the application of Eupatorium mulch or brown manuring (BM) of Sesamum was found effective for increasing yield and net returns in humid subtropical condition of Chitwan. Live mulching could be an eco-friendly weed control options in DSR. The BM option also provides crop residue for the addition of organic matter. This result suggests that BM is a potential alternative of herbicide application. Either mulching with Eupatorium and wheat straw or growing of Sesbania and Crotolaria as BM with rice up to 30 DAS are advisable to increase productivity with reduced cost of production at Chitwan and similar condition.

Being a maize producing region, cultivation of hybrid and improved maize varieties in the spring season is very low in Baitadi district. In order to examine the performances of different maize varieties, five maize varieties including both open-pollinated (i.e. Arun-2, Arun-4 and Rampur composite) and hybrid varieties (i.e. Rajkumar and Rampur Hybrid-10) were tested using Randomized Complete Block Design (RCBD) in spring season during February to August, 2020 at Dasarathch and municipality-1, Baitadi. The highest days to emergence of seedlings was in Rampur Hybrid-10 (30 days) and the lowest days to emergence was in Arun-2 (23 days) and Arun-4 (23 days), respectively. The plant height was significantly higher in Rajkumar (156.4 cm), whereas the leaf area index were significantly higher in Arun-2 (4.36 cm). Similarly, the phenological behavior like days to 50% tasseling (112 days) and silking (119 days) were significantly earlier in Arun-4. Likewise, yield attributing characteristics like cob length, cob diameter, number of rows/cobs, number of kernels/rows, shelling%, thousand grain weight (TGW) were found significantly higher in hybrid maize varieties as compared to openpollinated varieties. Grain yield was found significantly higher in hybrids Rajkumar recording yield of 5.32 Mt ha-1 closely followed by Rampur Hybrid-10 (4.75 Mt ha-1) whereas open-pollinated Rampur composite, Arun-2 and Arun-4 recorded grain yield of 4.58 Mt ha-1, 3.99 Mt ha-1 and 2.33 Mt ha-1 respectively. The results indicated that hybrid varieties were promising and should be promoted for general cultivation in the hills area of Nepal. SAARC J. Agric., 19(2): 123-136 (2021)

AbstractA field experiment was carried out to study the effect of spacing and nitrogen level on growth and yield of maize in Parbat from February to July, 2019. The experiment was laid out in two Factorial Randomized complete Block Design (RCBD) comprising of spacing: 60×15 cm and 60×25 cm and nitrogen: 30, 60, 90 and 120 kg/ha level as treatment with three replications. “Arun-2” variety of maize was planted on clay loam and acidic soil (pH 5.3) having medium in total nitrogen (0.15%), medium in soil available phosphorus (48.1 kg/ha), medium in soil available potassium (218.8 kg/ha) and medium in organic matter content (2.92%). Result shows that yield was significantly increased with increment in N-level up to 90 kg N/ha. The grain yield (5.18 mt/ha) was significantly higher at 90 kg N/ha than at 30 and 60 kg N/ha but at par with 120 kg N/ha. Significant effect on grain yield due to spacing was observed. The grain yield (4.11 mt/ha) obtained at spacing 60×15 cm. Moreover, the highest grain yield showed that highest grain yield (4.33 mt/ha) was obtained under 90 kg N/ha plus 60×15 cm spacing. The result revealed that different spacing and nitrogen level significantly affect the plant height and leaf area index. The plant height and leaf area index were significantly high at close spacing (60×15 cm) and at 120 kg N/ha. Likewise, yield attributing characteristics like cob length, cob diameter, number of kernel/rows, number of kernel row, thousand gran weight were the highest at 90 kg/ha but as par with 120 kg/ha at close spacing (60×15 cm). This study suggested that maize production can be maximized by cultivating “Arun-2” maize fertilizing with 90 kg N/ha and maintaining 60×15 cm spacing.