Evaluation of open pollinated and hybrid maize varieties in Dhading district of Nepal

Five maize varieties namely Rampur composite, Arun-2, Manakamana-3, Rampur Hybrid-4 and Rajkumar were evaluated in randomized complete block design with four replications at farmers field at Nilkantha Municipality-09, Aashikhola, Dhading from February 2018 to June 2018 to identify high yielding maze  varieties. Significant variation  was observed for grain yield, silking and tasseling, number of kernels per cob and cob length.The largest cob length was found in Rampur composite (19.550 cm) and highest number of kernel row per cob  was found in Rajkumar (17.25) and Manakamana-3 (17.25).The highest number of leaves above cob  was found in Rampur composite (5.678). The number of days for 50% tasseling and number of days for 50% silking had a highly significant and positive correlation with plot yield. The highest number of days for 50% tasseling (78.50 DAS) and days for 50 % silking (82.50 DAS) was observed in the genotypes Rampur Hybrid-4. Similarly, the number of leaves above the cob , thousand kernel weight and length of the cob  had a significant and positive correlation with plot yield. Rampur Hybrid -4 was the highest yielding genotype (7.79 t/ha) for such domain area with a B:C ratio of 1.48.Thus, Rampur Hybrid-4 genotype is recommended for spring season in Dhading

Performance of potato (Solanum tuberosum L.) varieties with and without straw-mulch at Shankharapur, Kathmandu, Nepal

The suitability of crop varieties in a particular location determines the productivity of crops. A field experiment was conducted from February to May 2020 at Shankharapur, Kathmandu, Nepal to evaluate the growth and productivity of potato varieties with and without mulch. Five potato varieties (Cardinal, Janakdev, Khumal Bikas, MS- 42.3, Panauti Local) were evaluated under straw-mulch and no-mulch conditions. The treatments were arranged in two factorial Randomized Complete Block Design (RCBD) with 3 replications. The results revealed that the highest tuber yield was produced by Janakdev (34.29 t ha-1) followed by Panauti Local (29.52 t ha-1). Similarly, straw-mulch gave higher yield (25.9 t ha-1) as compared with no mulch condition (21.73 t ha-1). The higher tuber yield in the Janakdev and Panauti Local was because of higher tuber weight per hill, higher number and weight of medium size (50 -100 g) and oversize (> 100 g) tuber per hill. Similarly, higher yield in straw mulch was due to higher number and weight of tuber per hill. Higher gross return, net return was observed and the benefit cost ratioin varieties Janakdev (4.08) and Panauti Local (3.53) and rice straw mulch (2.88). Therefore, potato varieties Janakdev and Panauti Local with straw mulch are most suitable for Kathmandu like climate for improving productivity and profitability

Bridging yield gap of winter maize using improved agronomic management practices

Appropriate combinations of inputs determine the productivity of crops. A field experiment was carried out to evaluate the effect of different combinations of inputs on the yield of winter maize at National Maize Research Program (NMRP), Rampur, Chitwan. The experiment was laid out in randomized complete block design with four replications comprising of six treatments (T1= Hybrid (H) + recommended doses of NPK (RD) + irrigation (I) + high density (HD) (83333 plant ha-1) + improved weed management practice (IWMP), T2=Open pollinated variety (OPV)+RD+I+HD+IWMP, T3=OPV+ farmer’s doses of NPK (FD)+I+HD+IWMP, T4= OPV+FD+rainfed (R)+HD+IWMP, T5=OPV+ FD+ R+low  density (LD) (55555 plant ha-1) + IWMP, T6=OPV+FD+R+LD+ farmer’s weed management practice (FWMP). The research result revealed significant variation on the grain yield among the different treatments. The highest grain yield (5357 kg ha-1) was obtained when hybrid maize was grown with recommended dose of fertilizer, higher density, irrigation and improved weed management practices. This treatment was followed by replacement of OPV in the above treatment (4410.77 kg ha-1). The decline in yield due to replacement of OPV from hybrid was 17.67 percent. The percent yield decline from full Package of practices (T1) were 23.01, 47.81, 36.66 and 35.95 when input combinations OPV+FD+I+ HD+IWMP, OPV + FD+R+HD+IWMP, OPV+FD+R+LD+IWMP and OPV+FD+R+LD+ FWMP respectively were used..The contrast for grain yield between hybrid vs. OPV, RD vs. FD and Irrigated vs. Rainfed were significant. Therefore, present investigation showed hybrid maize, recommended dose of fertilizer and irrigation were the most important inputs for improving maize productivity in winter season in Chitwan like climatic condition

Nitrogen uptake and economics of black rice (Oryza sativa L. indica) under different crop geometries and nitrogen management practices

Black rice has more antioxidants than any other rice variety.  It is considered to have multiple benefits in human health due to the presence of different antioxidants. A field experiment was conducted during rainy season of 2015-2016 to assess the nitrogen uptake, use efficiency and economics of black rice production under different crop geometry and nitrogen (N) management practices in Rampur, Chitwan, Nepal. The experiment was laid out in strip plot design with three replications. The experiment consisted of  treatment combination of three crop geometry (20 cm × 20 cm, 20 cm × 15 cm and 15 cm × 15 cm) in vertical plots and three nitrogen management practices (N level: 30 kg N ha-1, 60 kg N ha-1, and LCC based N-management) in horizontal plots. The results showed that the highest N uptake was recorded from closer spacing (15 cm × 15 cm) with LCC based N management. The net return and B: C ratios were higher at a closer spacing of 15 cm × 15 cm with LCC based N management and closer spacing of 15 cm × 15 cm with N application of 60 kg ha-1. The overall analysis revealed that LCC based N management under closer crop geometry (15 cm × 15 cm) was the best management practices because of high nitrogen uptake and highest monetary return with B: C ratio of 5.76

Frequency distribution and mean comparisons of red light absorbance- transmittance of the e1 leaf sectors of five pipeline maize hybrids during early grain filling in subtropical winter Precision of chlorophyll meter measures

ABSTRACT Background: Crop scientist"s curiosities were to examine variation in photosynthetic sectors of grain filler leaf or flag leaf of any major crop species. Crop scientists including plant breeders too will be privileged from the findings. So it includes such precision evaluation of single cross pipeline hybrids of yellow maize before their release as cultivars. Materials and methods: For it, five pipeline hybrids were examined from two trials of RCBD trial that they were in a big research plot with uniform soil fertility level and with the same control environment. Each of the trials was conducted planting the seeds of the fifteen newly bred separate hybrids on October 3, 2012 exposing their flowering and early grain filling to the natural winter in the subtropical region in Nepal. Five plants of the pipeline hybrids of the fifteen plots of three replications were randomly selected and tagged from each of the fifteen plots of the five hybrids before tassel emergence. After about one month of anthesis, one hundred observations of red light absorbance-transmittance (RAT) measures were taken from chlorophyll meter "SPAD 502" (Soil Plant Analysis Development) from the just-above-ear (e1) leaf of each of the selected plants of the hybrids in three days from 99 to 101 days after sowing (DAS). Results and discussion: From analysis of frequency distribution of the RAT SPAD measures of the e1 leaf sectors, it is not necessary that hybrids that demonstrates curve with high kurtosis always yield higher. Among the five hybrids, second highest grain yielding hybrid 112 had least leaf sectors of very low RAT SPAD measures. Besides, the hybrid 112 has been found least skewed and least peaked among the five hybrids. Furthermore, the hybrid 112 displayed least coefficient of variation and standard deviation among the 1500 RAT SPAD readings of its e1 leaf sectors. From the mean analysis through DMRT (Duncan Multiple Range Test), the twenty four averages have been found almost non-significant different among themselves inside each of the five hybrids. Singl

Strategies to improve cereal production in the Terai region (Nepal) during dry season: simulations with aquacrop

Strategies to improve cereal yield in Terai (Nepal) were developed with AquaCrop by simulating different scenarios of irrigation and fertilizer management for three dominant soil types with 30 years historical climatic data. Farmers yield increased from 25 to 115% depending on soil type, fertility and irrigation level. Considering the low availability of irrigation water and fertilizers, use of deficit irrigation with 1/4 of the net irrigation requirement (Inet) and fertilizer application below 50% of national recommended fertilizer dose (NRFD) was regarded as the most suitable strategy. For fertilizer applications above 50% of NRFD, deficit irrigation with 1/3 Inet is recommended.status: publishe

Influence of Sowing Date on Phenology, Biometric, and Yield of Mungbean (Vigna radiata) Cultivars in Chitwan, Nepal

Mungbean is a commercially promising legume crop, accounting for a very low productivity of approximately 0.5 tons ha1 in the Terai region of Nepal. This study aimed to achieve the potential yield of mungbean promising cultivars planting at optimum sowing time. An experiment was conducted at the Agriculture and Forestry University (AFU), Rampur, Chitwan, during the spring of 2019 in a split-plot design (SPD) with three replications and 16 treatment combinations. Four sowing dates at 15 days intervals (13th February, 28th February, 15th March, and 30th March) of 2019; cultivars viz. Kalyan, Pratikshya, Pratigya, and Pant-5 are considered as main and subplot factors. The Dunken test was carried out to compare the mean in R-software at p≤0.05 level of significance. The results revealed that earlier planting (Feb 13 planting) resulted in delayed emergence, slower growth, and the lowest yield (1.79 tons/ha). The March 15 to March 30 plantations resulted in significantly faster emergence, germination, and growth showing a higher yield. Pant-5 yielded a higher grain yield, which was statistically at par with Partigya (2.08 tons/ha) and Partikshya (1.983 tons/ha). Vigna radiata plantations from March 15 to March 30 are the optimum sowing times for higher productivity (2.119 tons/hectare) and high potential yield, which can be applied for perfect decision-making in mungbean plantations. Future work on least-squares analysis for understanding the genotypic-environment interaction of economic traits and the effect of different nutrient sources on cultivars has scope

Cereal yield stabilization in Terai (Nepal) by water and soil fertility management modeling

Rice (Oryza sativa L.), maize (Zea mays L.) and wheat (Triticum aestivum L.) are the major cereals cultivated in the Terai region of Nepal. In the region, agriculture is mainly rainfed and fertilizer applications are low. In this study, water and soil fertility management was modeled with the FAO AquaCrop model. For the model calibration and validation, field trials were set up during two years in Rampur, a representative area of Terai at Chitwan. The statistical comparison between the simulated and observed yield of the validation fields resulted in an average RRMSE (relative root mean squared error), R2 (coefficient of determination) and EF (Nash–Sutcliffe efficiency) of 0.05, 0.94 and 0.90 for rice, 0.08, 0.90 and 0.87 for wheat and 0.08, 0.97 and 0.96 for maize, respectively. The validated model was subsequently used to simulate different scenarios with 30 years of historical climatic data to determine realistic soil fertility and water management strategies for increasing crop yields. For the monsoon crops (rice and maize) that benefit from abundant rainfall, only an improved fertility management could increase crop yields by up to 65% and 58%, for rice and maize, respectively. During the winter and spring, seasons with lesser rainfall, crops were severely under-watered in absence of irrigation. For winter wheat, application of deficit irrigation increased yield by up to 67–197% compared to the rainfed crop yield for different fertility levels. For spring maize, full irrigation with increased fertilizer application was recommended to increase the yield. However, by considering the water scarcity in the region, application of deficit irrigation resulted in good and stable yields under low to moderate fertility and always resulted in a better water productivity than fully irrigated crops. It was demonstrated that increasing soil fertility of the winter and spring crops without considering irrigation could sometimes result in crop failure, instead of a yield increase. For fertilizer applications above 50% of the national recommended fertilizer applications, full irrigations are recommended for best yield results for winter and spring crops.status: publishe

Dynamics of chlorophyll and N concentration on e0 and e3 leaves of maize hybrids in winter in subtropical region Red light absorbance through maize

ABSTRACT National maize productivity is very low in Nepal. Increase of the productivity is only possible through growing high grain yielding single cross hybrid maize cultivar. So, development and evaluation of maize hybrids are principal steps to select high grain yielding and superior hybrid for cultivar. For it, fifteen newly bred single cross hybrids of yellow maize were examined from the standpoint of chlorophyll (chl) dynamics and their effects on grain yield. the kernels more efficiently from the e3 leaf. It is not necessary that maize hybrids must constantly maintain soluble proteins and chl conc during most of early to mid-grain filling duration for high grain yield. Instead, diagnostic decline of the soluble protein and chl conc during early to mid-grain filling also accelerate grain filling phenomena

Frequency distribution and mean comparisons of red light absorbance-transmittance of the e1 leaf sectors of five pipeline maize hybrids during early grain filling in subtropical winter Precision of chlorophyll meter measures

ABSTRACT Background: Crop scientist's curiosities were to examine variation in photosynthetic sectors of grain filler leaf or flag leaf of any major crop species. Crop scientists including plant breeders too will be privileged from the findings. So it includes such precision evaluation of five single cross pipeline hybrids (Hs 6, 112, 14, 113 and 109) of yellow maize using red light absorbancetransmittance (RAT) measure by chlorophyll meter SPAD 502 before their release as cultivars. Materials and methods: For it, five pipeline hybrids were examined from two RCBD trials that they were in a big research plot with uniform soil fertility level and with the same control environment. Each of the trials was conducted planting the seeds of the fifteen newly bred separate hybrids on October 3, 2012 exposing their flowering and early grain filling to the natural winter in the subtropical region in Nepal. Five plants of the pipeline hybrids of the fifteen plots of three replications were randomly selected and tagged before tassel emergence. After about one month of anthesis, one hundred observations of the RAT SPAD measures were taken from the chlorophyll meter from the just-above-ear (e1) leaf of each of the selected plants of the hybrids of 180 to 185 days of crop maturity in three days from 99 to 101 days after sowing (DAS). Results and discussion: From analysis of frequency distribution of the RAT SPAD measures of the e1 leaf sectors, it is not necessary that hybrids that demonstrates curve with high kurtosis and high RAT SPAD measures always yield higher. Among the five hybrids, secon