Management of blast disease of finger millet (Eleusine coracana L. Gaertn) caused by Pyricularia grisea under field conditions in Dolakha, Nepal

Lack of understanding regarding the choice of chemical fungicides or botanicals with their optimal doze and spraying schedule is one of the major problems concerning mid-hill farmers to control finger millet diseases in Nepal. In order to assess the effectiveness of the four fungicides, namely Bavistin 50 WP (Carbendazim 50%), SAAF (Carbendazim 12% + Mancozeb 63% WP), RIDOMIL-MZ 72 WP (Metalyxl 8% + Mancozeb 64% WP), BAAN 75 WP (Tricyclazole 75%), and two botanicalsermented anaerobically in cattle urine, an artificial epiphytotic field. In the years 2018 and 2019, the experiment was run using a randomized complete block design with three replications. Carbendazim, one of the chosen treatments, had the greatest impact in lowering the AUDPC values for leaf blast (1818, 1191) as well as neck (4,53) and finger blast (10,45) incidence percentage in both 2018 and 2019 years. Tricyclazole, SAAF, RIDOMIL-MZ, and Lantana camara fermented in cow urine were also discovered to be beneficial throughout the year.  So it is recommended to deploy fungicides in a controlled manner through rotation and mixed applications, which is advantageous for both grain and seed production even for minor and underutilized crops from an economic aspect

Grain Yield Stability of Rice Genotypes

Stability analysis identifies the adaptation of a crop genotype in different environments. The objective of this study was to evaluate promising rice genotypes for yield stability at different mid-hill environments of Nepal. The multilocation trials were conducted in 2017 and 2018 at three locations viz Lumle, Kaski; Pakhribas, Dhankuta; and Kabre, Dolakha. Seven rice genotypes namely NR11115-B-B-31-3, NR11139-B-B-B-13-3, NR10676-B-5-3, NR11011-B-B-B-B-29, NR11105-B-B-27, 08FAN10, and Khumal-4 were evaluated in each location. The experiment was laid out in a randomized complete block design with three replications. The rice genotype NR10676-B-5-3 produced the highest grain yield (6.72 t/ha) among all genotypes. The growing environmental factors (climate and soil conditions) affect the grain yield performance of rice genotypes. The variation in climatic factors greatly contributed to the variation in grain yield. Polygon view of genotypic main effect plus genotype-by-environment interaction (GGE) biplot showed that the genotypes NR10676-B-53 and NR11105-B-B-27 were suitable for Lumle; NR11115-B-B-31-3 and NR11139-B-B-B-13-3 for Pakhribas; and 08FAN10 and NR11011-B-B-B-B-29 for Kabre. The GGE biplot showed that genotype NR10676-B-5-3 was stable hence it was near to the point of ideal genotype. This study suggests that NR10676-B-5-3 can be grown for higher grain yield production in mid-hills of Nepal

Variation in grain zinc and iron concentrations, grain yield and associated traits of biofortified bread wheat genotypes in Nepal

Wheat (Triticum aestivum L.) is one of the major staples in Nepal providing the bulk of food calories and at least 30% of Fe and Zn intake and 20% of dietary energy and protein consumption; thus, it is essential to improve its nutritional quality. To select high-yielding genotypes with elevated grain zinc and iron concentration, the sixth, seventh, eighth, and ninth HarvestPlus Yield Trials (HPYTs) were conducted across diverse locations in Nepal for four consecutive years: 2015–16, 2016–17, 2017–18, and 2018–19, using 47 biofortified and 3 non-biofortified CIMMYT-bred, bread wheat genotypes: Baj#1, Kachu#1, and WK1204 (local check). Genotypic and spatial variations were found in agro-morphological traits; grain yield and its components; and the grain zinc and iron concentration of tested genotypes. Grain zinc concentration was highest in Khumaltar and lowest in Kabre. Likewise, grain iron concentration was highest in Doti and lowest in Surkhet. Most of the biofortified genotypes were superior for grain yield and for grain zinc and iron concentration to the non-biofortified checks. Combined analyses across environments showed moderate to high heritability for both Zn (0.48–0.81) and Fe (0.46–0.79) except a low heritability for Fe observed for 7th HPYT (0.15). Grain yield was positively correlated with the number of tillers per m2, while negatively correlated with days to heading and maturity, grain iron, grain weight per spike, and thousand grain weight. The grain zinc and iron concentration were positively correlated, suggesting that the simultaneous improvement of both micronutrients is possible through wheat breeding. Extensive testing of CIMMYT derived high Zn wheat lines in Nepal led to the release of five biofortified wheat varieties in 2020 with superior yield, better disease resistance, and 30–40% increased grain Zn and adaptable to a range of wheat growing regions in the country – from the hotter lowland, or Terai, regions to the dry mid- and high-elevation areas

Management of blast disease of finger millet (Eleusine coracana L. Gaertn) caused by Pyricularia grisea under field conditions in Dolakha, Nepal

Lack of understanding regarding the choice of chemical fungicides or botanicals with their optimal doze and spraying schedule is one of the major problems concerning mid-hill farmers to control finger millet diseases in Nepal. In order to assess the effectiveness of the four fungicides, namely Bavistin 50 WP (Carbendazim 50%), SAAF (Carbendazim 12% + Mancozeb 63% WP), RIDOMIL-MZ 72 WP (Metalyxl 8% + Mancozeb 64% WP), BAAN 75 WP (Tricyclazole 75%), and two botanicalsermented anaerobically in cattle urine, an artificial epiphytotic field. In the years 2018 and 2019, the experiment was run using a randomized complete block design with three replications. Carbendazim, one of the chosen treatments, had the greatest impact in lowering the AUDPC values for leaf blast (1818, 1191) as well as neck (4,53) and finger blast (10,45) incidence percentage in both 2018 and 2019 years. Tricyclazole, SAAF, RIDOMIL-MZ, and Lantana camara fermented in cow urine were also discovered to be beneficial throughout the year.  So it is recommended to deploy fungicides in a controlled manner through rotation and mixed applications, which is advantageous for both grain and seed production even for minor and underutilized crops from an economic aspect.</jats:p

Assessment of wheat genotypes for spot blotch (Bipolaris sorokiniana Sacc.) resistance under artificial epiphytotic conditions in the inner terai of Nepal

Spot blotch, caused by (Bipolaris sorokiniana Sacc.) is a significant fungal disease leading to economic losses in wheat (Triticum aestivum), especially in regions with low soil fertility and warm, humid climates, such as the inner Terai of Nepal. A field experiment was conducted at the National Maize Research Program (NMRP), Rampur, Chitwan, during winter of 2021/022 with an aim of identifying wheat genotypes with spot blotch resistance under artificial epiphytotic conditions. Each genotype was sown in a single 2-meter long row alongside susceptible check genotypes (Agra and Morocco) at every 20th row. Aqueous spore suspension of B. sorokiniana was applied twice in border rows during the booting stage at 15-day intervals. Disease severity was assessed four times at five-day intervals using a double-digit scale based on the percentage blighted area on the flag and penultimate leaf, and the area under the disease progress curve (AUDPC) was calculated. The results categorized 43 genotypes as resistant, 127 as moderately resistants, 135 as moderately susceptible, 66 as susceptible, and 7 as highly susceptible based on AUDPC. Cluster analysis identified cluster 3 comprising 17 genotypes as superior in terms of disease resistance as well as agronomic parameters. NRN-34 emerged as the top-ranked genotype within this cluster, followed by NAL-73, NAL-94, NAL-12, NRN-34, NAL-57, NAL-43, NAL-82, and NAL-35, exhibiting lower AUDPC values and higher yield-attributing character values.  This study will aid breeders in developing spot blotch-resistant and high-yielding wheat varieties by incorporating the identified promising genotypes into further breeding programs

Genotype × environment interaction of quality protein maize grain yield in Nepal

In order to determine G × E interaction of quality protein maize grain yield, six maize genotypes were evaluated under different environments of three Terai (Chitwan, Surkhet and Doti) and four mid hill (Dhankuta, Lalitpur, Dolakha and Kaski) districts of Nepal during summer seasons of 2014 and 2015. The experiments were conducted using randomized complete block design along with three replications. The genotypes namely S99TLYQ-B, S99TLYQ-HG-AB and S03TLYQ-AB-01 were identified high yielding and better adapted genotypes for Terai environments with grain yield of 4199 kg ha-1, 3715 kg ha-1, and 3336 kg ha-1 respectively and S99TLYQ-B and S03TLYQ-AB-01 for mid hill environments with grain yield of 4547 kg ha-1 and 4365 kg ha-1 respectively. Therefore, these genotypes can be suggested for cultivation in their respective environments in the country

Grain Yield Stability of Rice Genotypes

Stability analysis identifies the adaptation of a crop genotype in different environments. The objective of this study was to evaluate promising rice genotypes for yield stability at different mid-hill environments of Nepal. The multilocation trials were conducted in 2017 and 2018 at three locations viz Lumle, Kaski; Pakhribas, Dhankuta; and Kabre, Dolakha. Seven rice genotypes namely NR11115-B-B-31-3, NR11139-B-B-B-13-3, NR10676-B-5-3, NR11011-B-B-B-B-29, NR11105-B-B-27, 08FAN10, and Khumal-4 were evaluated in each location. The experiment was laid out in a randomized complete block design with three replications. The rice genotype NR10676-B-5-3 produced the highest grain yield (6.72 t/ha) among all genotypes. The growing environmental factors (climate and soil conditions) affect the grain yield performance of rice genotypes. The variation in climatic factors greatly contributed to the variation in grain yield. Polygon view of genotypic main effect plus genotype-by-environment interaction (GGE) biplot showed that the genotypes NR10676-B-53 and NR11105-B-B-27 were suitable for Lumle; NR11115-B-B-31-3 and NR11139-B-B-B-13-3 for Pakhribas; and 08FAN10 and NR11011-B-B-B-B-29 for Kabre. The GGE biplot showed that genotype NR10676-B-5-3 was stable hence it was near to the point of ideal genotype. This study suggests that NR10676-B-5-3 can be grown for higher grain yield production in mid-hills of Nepal.</jats:p

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

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.</jats:p

Variation in Grain Zinc and Iron Concentrations, Grain Yield and Associated Traits of Biofortified Bread Wheat Genotypes in Nepal

Wheat (Triticum aestivum L.) is one of the major staples in Nepal providing the bulk of food calories and at least 30% of Fe and Zn intake and 20% of dietary energy and protein consumption; thus, it is essential to improve its nutritional quality. To select high-yielding genotypes with elevated grain zinc and iron concentration, the sixth, seventh, eighth, and ninth HarvestPlus Yield Trials (HPYTs) were conducted across diverse locations in Nepal for four consecutive years: 2015–16, 2016–17, 2017–18, and 2018–19, using 47 biofortified and 3 non-biofortified CIMMYT-bred, bread wheat genotypes: Baj#1, Kachu#1, and WK1204 (local check). Genotypic and spatial variations were found in agro-morphological traits; grain yield and its components; and the grain zinc and iron concentration of tested genotypes. Grain zinc concentration was highest in Khumaltar and lowest in Kabre. Likewise, grain iron concentration was highest in Doti and lowest in Surkhet. Most of the biofortified genotypes were superior for grain yield and for grain zinc and iron concentration to the non-biofortified checks. Combined analyses across environments showed moderate to high heritability for both Zn (0.48–0.81) and Fe (0.46–0.79) except a low heritability for Fe observed for 7th HPYT (0.15). Grain yield was positively correlated with the number of tillers per m2, while negatively correlated with days to heading and maturity, grain iron, grain weight per spike, and thousand grain weight. The grain zinc and iron concentration were positively correlated, suggesting that the simultaneous improvement of both micronutrients is possible through wheat breeding. Extensive testing of CIMMYT derived high Zn wheat lines in Nepal led to the release of five biofortified wheat varieties in 2020 with superior yield, better disease resistance, and 30–40% increased grain Zn and adaptable to a range of wheat growing regions in the country – from the hotter lowland, or Terai, regions to the dry mid- and high-elevation areas.</jats:p