Journal of Nepal Agricultural Research Council

Screening of Maize Genotypes against Maize Leaf Aphid [Rhopalosiphum maidis (Fitch)] under Field Condition at Chitwan, Nepal

2022-05-03T07:25:22+00:00

Thirty maize genotypes including five hybrids, eight quality protein (QPM) and seventeen full season open pollinated (OP) were screened for their resistance against maize leaf aphid (Rhopalosiphum maidis Fitch) at the research field of National Maize Research Program, Rampur, Chitwan, Nepal during the year 2019 and 2020. The design of the experiment was randomized incomplete block with three replications. The plot size was 2 rows of 5 m long with the spacing of 60 cm × 25 cm. The recommended dose of fertilizer for full season OP and QPM were 120:60:40 and for hybrid maize 180:60:40 N: P₂O₅:K₂O kg/ha with farmyard manure 10 t/ha and seed rate was 20 kg/ha. Data on aphid incidence, severity, yield and yield components were recorded. Maize hybrids RML-95/RML-96 (18%) and Rampur Hybrid-10 (22%), two quality protein maize (QPM) S00TLYQ-AB (22%) and S99TLYQ-A (23%) and two full season OP genotypes TLBRS07F16 (24%) and ZM 627 (26%) were less susceptible to aphid infestation and resulted in higher grain yield. The findings could aid in the selection of maize genotypes for the development of aphid resistant and high-yielding maize varieties.

Effect of Wrapping Materials and Maturity Stages on Postharvest Loss Reduction of Papaya

2022-05-03T10:07:21+00:00

Papaya fruits are vulnerable to high postharvest losses if harvesting and handling techniques are inappropriate. Therefore, an experiment was conducted in two consecutive years, 2019 and 2020, to assess the effects of wrapping materials and maturity stages on postharvest loss reduction of papaya stored at ambient condition. A factorial combination of four wrapping materials (brown paper, white paper, fiber bag, and control) and three maturity stages (MS2; few yellow streaks from base to stalk end of fruits, MS3; 1/2 ripe, and MS4; 3/4 ripe), using a completely randomized design (CRD) with three replications was used to carry out this experiment. The papaya fruits were evaluated for transportation weight loss, bruised fruit percent, physiological weight loss, decay percent, total soluble solids, firmness, and shelf life. The result revealed that wrapping materials significantly affected on the transportation weight loss, percent bruised fruit, decay percent, and shelf life. The stage of maturity had a significant effect on TSS and firmness of the fruit. However, the interaction of wrapping materials and maturity stages had a non-significant effect on all the parameters. Out of the four wrapping materials, brown paper wrapped fruits had the lowest bruised fruit (4.1%), the lowest decay (10.8%), and the highest shelf life (11.8 days), while MS2 showed the minimum bruised fruit (15.1%), decay (21.2%), and shelf life (12.8 days). Fruit harvested at MS2 wrapped with brown paper can reduce postharvest loss and improve shelf life of papaya.

Application of Nitrogenous Fertilizer in Rice Production: A Review

2022-05-03T13:09:53+00:00

Rice (Oryza sativa L.) is one of the world's most important cereal crops. Nitrogen is one of the most important plant nutrients for rice. Different forms of nitrogenous fertilizer are the major sources of nutrients in rice production. Nitrogen affects various physiological and biochemical processes in plant cells that ultimately affect the growth and development and, thereby, the grain yield of rice. Rice production can be increased by applying nitrogenous fertilizer either as organic or inorganic fertilizer at an appropriate dose, time, method, and place. Soil testing is needed to assess the nutritional status of the soil as it is affected by crop nutrient uptake and removal. Nitrogenous fertilizers should be applied in multiple split doses depending upon the nutrient status of the soil, crop demand, and sources of nutrients. To reduce the nitrogen loss from rice fields, surface runoff, denitrification, ammonium volatilization, and leaching should be managed. Sustainable and environmentally friendly fertilizer management practices enhance the sustainable soil fertility status and, thereby, crop yields. This review article examines the impact of nitrogenous fertilizers on rice growth, development, and production, along with time and doses of nitrogen applications that will help agricultural technicians, academicians, farmers, and policy makers.

Assessment of Proso millet Genotypes against Blast Caused by Pyricularia grisea (Cooke) Sacc. under Field Condition at Mid Hill Region of Nepal

2022-05-04T09:51:08+00:00

A total of 14 proso millet genotypes, including the farmers' variety, which was the most commonly cultivated landrace in the Karnali region and most susceptible to blast disease as a susceptible check, were evaluated for resistance to leaf blast at the Hill Crops Research Program, Kabre, Dolakha, Nepal during the summer seasons of 2020 and 2021. The experiment was conducted under natural epiphytotic conditions. The experiment revealed that none of the tested genotypes were found immune or highly resistant. Most of the genotypes showed moderately susceptible and susceptible reactions to the leaf blast disease for both experimental years. However, genotypes C04654, Humla-239, and C04651 were found to have lower blast severity and produce higher grain yields. Genotype C04654 was found as resistant with 34.6% disease severity and high yielding (2.6 t/ha), followed by Humla-239 and C04651 as moderately susceptible with 44.8 and 45.9% disease severity resulting grain yields of 2.5 and 2.4 t/ha, respectively. The higher disease severity (68.1%) with lower grain yield (1.4 t/ha) was recorded in the farmer's variety (susceptible check). The genotypes reported with lower blast severity and higher grain yield could be the source for the release of a leaf blast resistant and high-yielding proso millet variety in the mid-hill region of Nepal.

Multi-Environment Screening of Nepalese Finger Millet Landraces against Blast Disease [Pyricularia grisea (Cooke) Sacc.)]

2022-05-04T12:18:08+00:00

Three hundred finger millet genotypes (295 landraces from 54 districts and five released varieties) were evaluated for leaf, finger, and neck blast resistance under natural epiphytotic conditions across three hill locations in Nepal, namely Kabre, Dolakha (1740m); Vijaynagar, Jumla (2350 m); and Khumaltar, Lalitpur (1360 m) during the summer seasons of 2017 and 2018. The highest incidence of leaf, neck, and finger blast was observed at Lalitpur, followed by Dolakha and Jumla, whereas the overall disease incidence was higher in 2018 compared to 2017. Combined analysis over environments revealed non-significant differences among accessions for leaf blast, but the difference was highly significant for neck and finger blast. Correlation analysis suggested that there was a strong positive correlation between neck blast and finger blast (r = 0.71), leaf blast (seedling stage) and neck blast (r = 0.68), and leaf blast (seedling stage) and finger blast (r = 0.58) diseases. Among 300 accessions, 95 had lower scores for finger blast, 30 for neck blast, and 74 for leaf blast than the score of Kabre Kodo-2, the latest released variety in Nepal. Genotypes NGRC04798, NGRC03478, NGRC05765, NGRC03539, NGRC06484, NGRC01458, NGRC01495 and NGRC01597 were found the resistant genotypes for finger blast (2.1-2.3) and neck blast (1.5-2.3) based on pooled mean scores. This study shows the variable reactions of finger millet genotypes against blast disease in various environments and reports the promising landraces having field resistance to leaf, finger, and neck blast, which ultimately serve as important donors for blast resistance in finger millet breeding.

Effect of Organic Manures and Chemical Fertilizers on Maize Productivity and Soil Properties in the Winter Season

2022-05-04T10:25:57+00:00

Field experiments were conducted at the National Maize Research Program Rampur, Chitwan, Nepal, during the two consecutive winter seasons of 2018/19 and 2019/20. The objective was to identify the effects of different sources of nutrients on the growth and yield parameters of winter maize and soil properties. The experiment was laid out in a randomized complete block design with three replications and twelve treatments. Combinations of different organic and inorganic sources, including the recommended dose of chemical fertilizer, farmyard manure, poultry manure, biochar, vermicompost, mustard oil cake, sunhemp and bone meal, were tested. Different nutrient levels significantly influenced the maize grain yield. The maximum grain yields of 7102 kg/ha (2018/19) and 6985 kg/ha (2019/20) were obtained with the combined application of 50% recommended dose (RD) of chemical fertilizer along with mustard oilcake at the rate of 5 t/ha, which was at par (6969 kg/ha and 6535 kg/ha) with the sole application of mustard oilcake at 10 t/ha. It can be concluded that the highest grain yield (7043.5 kg/ha) was obtained when 50% of the recommended dose of N, P2O5 and K2O fertilizers were combined with 5 t mustard oilcake/ha application, followed by sole application of 10 t mustard oilcake/ha (6752 kg/ha). Soil properties including organic matter were found to be significantly improved due to the application of a combined application of organic and inorganic fertilizer. Thus, in subtropical conditions, integrated organic manures and chemical fertilizers can enhance soil
properties and increase maize productivity during the winter season.

Reproductive and Productive Performance of Crossbred and Terai Cattle in Bardiya District of Nepal

2022-05-04T10:46:59+00:00

To compare the reproductive and productive performance of exotic crossbreds and indigenous Terai cattle under farmers' management condition, a household survey was carried out in 218 households of Bardiya, Nepal. Total of 262 cows [Jersey cross (n=107), Holstein cross (n=24) and indigenous Terai cattle (n=131)] were considered to determine the production and reproduction parameters. The age at first calving in months was the lowest in Jersey crossbred (27.8±1.8) followed by Holstein cross (29.5±4.0) and Terai cattle (45.7±3) (P<0.05). However, the number of services per conception, calving to conception interval (in months) and inter-calving interval (in months) were shorter in Terai cattle (1.3±0.7, 3.4±1.4 and 12.6±1.9) compared to Jersey cross (1.7±1.3, 4.4±2.2 and 13.5±3.1) and Holstein cross (1.8±0.9, 5.7±2.8 and 14.9±4.7), respectively (P<0.05). Total 6.5% of cattle had a history of reproductive problems; Incidence of repeat breeding tended (P<0.1)) to be higher in Jersey cross (8.4%) and Holstein cross (8.3%) than in Terai cattle (3.0%). Daily peak milk yield (L/day) was significantly lower in Terai cattle (1.7±1.1) than Jersey cross (13.5±3.1) and Holstein cross (14.9±4.7). The lactation length (months) was significantly shorter in Terai cattle than exotic crossbreds. Consequently, the length of dry period (in months) was significantly longer in Terai cattle (5.2±2.1) than in Jersey cross (2.5±0.9) and Holstein cross (2.2±0.7). The reproductive performance parameters in exotic crossbred cows under the farmers' management condition were satisfactory; however, their productivity was low. Thus, the good reproductive traits and variations in productivity of Terai cattle can be utilized in cross breeding programs.

Resource Use Efficiency (RUE) in Lentil Production in Terai and Inner Terai Regions of Nepal

2022-05-04T10:59:15+00:00

A study was carried out to estimate and analyze the profitability and resource use efficiency of lentil grain and seed production in Nepal's terai and inner terai regions. Using a pre-tested questionnaire, primary data and information were collected from 300 lentil grain producing farmers, categorized by local seed users, improved seed users, and 100 seed producing farmers in Kailali, Dang, and Siraha districts. The study revealed that the B:C ratio in lentil seed production was higher (1.59) than in lentil grain production (1.41). The benefit in both grain and seed production realized by farmers was mainly due to increased prices rather than production. Return to scale was found to be increasing (1.016) in lentil grain production using local seed, but it was decreasing at a rate in lentil grain production using improved seed (0.854) and in lentil seed production (0.822). Analysis on resource use efficiency revealed that labor input is excessively overused, reflecting the Marginal Value Product of less than unity in lentil production. To get the maximum profit from lentil grain production using improved seed, input use in land preparation, threshing, and post-harvest should be increased while decreasing the amount of other inputs.

Multi-year Prediction of Rice Yield under the Changing Climatic Scenarios in Nepal Central Terai Using DSSAT Crop Model

2022-05-04T11:19:35+00:00

NASA-POWER derived weather data of Dumkauli in Nawalparasi (27.68˚ N, 84.13˚E) district in the Nepal central Terai for the past 33-years (1984/85-2017/18) were purposively downloaded and validated with recorded weather data of Department of Hydrology and Meteorology (DHM). The trend analysis for grain yield of rice in Nawalparasi was drawn with the historical data of the maximum and minimum temperatures and rainfall. Positive correlations between grain yields and minimum temperature and rainfall each showed an acceptable coefficient of determination (R²). The CSM-CERES-Rice embedded in DSSAT ver 4.7 was used for multi-year prediction of rice yield using both historically recorded and simulated climatic scenarios. The model simulated results closely agreed with the observed rice yield recorded by the Ministry of Agriculture and Livestock Development (MoALD) in Nepal. The correlation between precipitation and observed rice yield was 0.71 and the correlation between precipitation and observed and DSSAT simulated yield was 0.379. The multi-year predicted rice yield using historical weather data and the DSSAT rice model showed that rice yield could be sustained with the use of the current crop cultivars only for the upcoming few years. The climate index, mainly the rainfall index, was found to be more sensitive to rice production in the Nepal central Terai region. This study suggests for the development of new climate change ready rice cultivars to feed the increasingly growing Nepalese population.

Production Performance and Nutrient Composition of Fodder Triticale (x Triticosecale W.)

2022-05-04T11:50:07+00:00

A study was undertaken to compare the productivity and nutrient compositions of different varieties of fodder triticale (xTriticosecale W.) from 2019 to 2021. The experiments were laid-out in a Randomized Complete Block Design with four treatments consisting three varieties of triticale (Winter Max, Crack Jack, and Bolt) and one local wheat variety (as a check), with three replications. The fodder dry matter (DM) yields of evaluated varieties significantly varied (p<0.05) in 2020 and in 2021, although it was non-significant in pooled data analysis of three years. The interaction effects of the varieties and locations on fodder dry matter yield were non-significant in 2019, 2020 and pooled data analysis of three years but was significantly different in 2021. The seed yield was statistically different for the varieties in different years and also in pooled data analysis. Similarly, the interaction effects of varieties and locations were significantly different in seed yields in all three years. The seed yields were significantly different for the fodder triticale varieties in both the locations and pooled data analysis. The interaction effects of varieties and years were significant for seed yields. The average protein percentage was ranged from 8.88 to 10.39%. Bolt performed well in terms of dry matter and Winter Max did well in terms of seed production in different years while Crack Jack was found to be best for the protein percentage. The temporal and spatial effects on varieties indicate the need of the further niche or region-specific studies.