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In wheat development programs, the evaluation and identification of superior genotypes  is the first and leading step in a crop improvement program. Coordinated Farmer’s Field Trial (CFFT) was conducted during the three successive wheat growing season of 2010/11, 2011/12 and 2012/13. In CFFT six different wheat genotypes were planted in different outreach sites of research stations of Nepal Agricultural Research Council (NARC) at varying geographical regions. CFFT was conducted according to standard recommended practices of wheat at farmers’ field with different sets of genotypes for Terai and hill. In CFFT for Terai Tar and Lower valley (TTL) under timely sown irrigated (TSI) condition wheat genotype NL 1073 produced the grain yield of 3695 kg/ha and under the timely sown rainfed (TSR) that was 2738 kg/ha in 2010/11. In 2011/12, wheat genotype NL 1073 had the highest recorded grain yield of 3691 kg/ha in mid western region which was followed by check variety Vijay in CFFT-TTL in 2011/12 in the same region. Similarly in 2012/13, check variety Vijay showed the highest grain yield of 3818 kg/ha and 3044 kg/ha followed by NL 1094 (2938 kg/ha and 3468 kg/ha) in TSR and TSI environments, respectively. In CFFT for Mid and High Hill (MHH) WK 1204 had the highest grain yield of 3967 kg/ha in TSI which was followed by NL 1008 with the yield of 3890 in 2010/11. In 2011/12 the highest mean grain yield was observed in WK 1204 (4242 kg/ha) followed by BL 3872 (3922 kg/ha). Similarly, in 2012/13 NL 1008 was the best genotypes on the basis of grain yield (3297 kg/ha) followed by NL 1055 (3131 kg/ha) under CFFT-MHH.

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 dryer mid- and high-elevation areas.

Multilocation testing of the Coordinated Varietal Trial (CVT) of wheat genotypes were conducted at different hill research stations of Nepal Agricultural Research Council (NARC) during the normal planting season of 2012/13 and 2013/14. Twenty genotypes including two check varieties were included in Randomized Complete Block (RCB) design with three replications in the experiment. Data on the different yield attributing traits were recorded.  Highly significant difference (p<0.01) among the genotypes for the days to heading, days to maturity, plant height, thousand grain weight and grain yield was observed in 2012/13. Wheat genotype BL 4061 had the highest grain yield with 3802 kg/ha followed by NL 1153 (3736 kg/ha), NL 1159 (3733 kg/ha), NL 1154 (3674 kg/ha) and NL 1156 (3462 kg/ha). In 2013/14 also a highly significant difference among the tested genotypes for all the recorded traits was observed and these genotypes were stable for the yield and yield attributing traits. The most promising genotypes for the grain yield was NL 1153 (5816 kg/ha) followed by NL 1178 (5760 kg/ha), NL 1156 (5454 kg/ha), NL 1159 (5259 kg/ha) and NL 1179 (5075 kg/ha). From the yield and other yield attributing trait wheat genotypes NL 1055, NL 1153, NL 1159, NL 1156 and NL 1179 need to be tested under farmers’ field for further confirmation and release as variety.

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Wheat, the third major staple crop of Nepal has been suffered from many diseases. Various diseases are the major limiting factors of considerable wheat production, one of them is Spot blotch. Spot blotch caused by Bipolaris sorokiniana is a major disease of wheat in warm and humid regions of the Nepal. The fungus has a worldwide distribution but as a pathogen it is the most aggressive under the conditions of high relative humidity and temperature associated with the low fertility of soils in South Asia, South America, Africa, and Australia. The yield loss due to the disease is very significant Nepal. This experiment was conducted to identify the genotypes (crossing) having good level of resistance against spot blotch. The experiment set was received from CIMMYT comprises 52 entries and arranged in alpha lattice design with two replication in 2012/13 at NWRP, Bhairahawa condition. Three times diseases scoring were done in double digit method and calculated the Area under disease progress curve (AUDPC). Heading days, days to maturity, plant height and test weight were found highly significant but the grain yield and AUDPC were not significant among the entries. However, the grain yield and test weight (50.5 gm) were found higher where the AUDPC was lower recorded in genotype 6719 (4046 kg/ha and AUDPC 488.33) followed by genotype 6737 (3765 Kg/ha and AUDPC 576.9) and genotype 6718 (3550 kg/ha and AUDPC 596.33). International Journal of Environment Volume-4, Issue-3, June-August 2015Page: 140-150