Genetic diversity must be maintained and utilized for sustainable agriculture development. The amount of genetic diversity in the country depends on the number and diversity of the original ancestors involved in the creation of a germplasm pool, wild relatives and existing landraces. The objective of this research was to study the diversity of wheat gene pool present in the Nepalese bread wheat cultivars and landraces that could help for developing conservation and utilization strategy effectively. We examined the pedigrees of 35 Nepalese wheat cultivars and surveyed the literature for distribution of landraces and wild relatives of wheat. Cultivated landraces of spring and winter type, wild landraces and diploid species of wheat are found in Nepal. There are 35 improved wheat cultivars, 540 landraces and 10 wild relatives of wheat. Crosses between winter and spring wheat gene pools are far more common and offer a new source of diversity. Mexico, India and Nepal are the origin countries for 35 cultivars. In Nepal four cultivars were bred and developed using foreign landraces and maximum number of cultivars was developed in Mexico. Lerma 52, first improved cereal variety to be released in the history of cereal breeding in Nepal was released in 1960. A total of 89 ancestors originated in 22 different countries were used to develop these cultivars. Highest number of ancestors was from India. Ancestors of both aestivum and durum species having winter, spring and intermediate growth habit indicated the collection of wide gene pool. Most of the ancestors were aestivum (76.40%) and spring growth habit (57.31%). Modern varieties are replacing the landraces and improved old varieties resulted in the genetic erosion. Therefore, in situ, on farm and ex situ conservations are necessary for maintaining these genetic variations. Unutilization of local landraces in breeding program may be the major factor that causes to accelerate the genetic erosion. Gene pool from these landraces along with international gene pool could make towards success in developing high yielding cultivars with wide adaptability. In this study, cultivars and landraces surveyed represent a wide range of variation for different areas of origin and adaptation.

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Foxtail millet (Setaria italica (L) P Beauv) falls on the category of underutilized crops in Nepal and mainly cultivated in Karnali region of the country. It is hardy crop and considered as one of the potential crops for future food security with respect to climate change. Five accessions of Nepalese foxtail millet were purposefully selected for evaluation of the agromorphological characteristics. Foxtail landraces from Dolpa, Mugu, Bajura, Bajhang and Lamjung districts of Nepal were evaluated at Khumaltar, Lalitpur, Nepal during 2010. The plot size was 1m 2 and there were five samples. Days to heading and days to maturity varied from 33-56 and 59 to 87 days after germination respectively. Similarly, flag leaf length/breadth ratio, flag leaf sheath length, ligule length, peduncle length, peduncle exertion and plant height varied from 3.84-10.90, 5.47-9.84 cm, 0.1-0.2 mm, 10-22.57 cm, 2.7-13.58 cm and 41.67-120 cm, respectively. Fruit and apiculus color varied from straw to black. All accessions were actively growing with very slight lodging. Similarly, the thousand grain weight varies from 1.064 g to 2.172 g. This variation is useful in foxtail millet breeding program. Similarly, the significant correlation between thousand kernel weight and total basal tiller (r=-0.975) showed that foxtail millet lines with low tillering ability is better for yield enhancement.

There are many socioeconomic and technological constraints that aVect the production of wheat and other staple cereals in South Asia. Wheat production is one of the economic mainstays in South Asia, but the yield gap between farmers' Welds and experimental yields is wide across the region. For the last 3 years, CIMMYT and the CAZS-NR have been collaborating with farmers, NARS, and other South Asian partners to promote improved wheat varieties and new resource conservation technologies (RCTs) in farmers' Welds. Participation fostered among farmers, scientists, extension specialists, NGOs and the private sector included variety selection (PVS), and evaluation of agronomic practices. Through PVS, several farmer-preferred technologies have been identiWed including wheat varieties for adverse conditions in eastern Uttar Pradesh (India) and for boron deWciency in parts of Nepal. There has been considerable improvement in the access of farmers to new varieties and technologies in the rural areas. Yield increases (15-70%) have been achieved by resource-poor farmers over the existing varieties through the adoption of new varieties and RCTs. The farmers have also made substantial cost savings and achieved higher yields through resource-conserving agronomic techniques such as zero till. Seed of the new farmerselected cultivars has been multiplied by groups of collaborating farmers and widely distributed.

The diversity of agro-environmental conditions among wheatbased farming systems in the mountainous regions of Nepal may favor the development and production of multiple narrowly adapted varieties over a few broadly adapted varieties. Sixteen genotypes were tested using Participatory Varietal Selection (PVS) trials at farmers' fields in three districts in the Kathmandu Valley.Grain yield was the trait most preferred by farmers, followed by tillering, resistance to diseases, drought, and lodging. Farmer selection of optimal genotypes varied over time and location depending on agronomic and climatic pressures, indicating a preference by farmers for growing multiple, narrowly adapted varieties. Production potential of PVS genotypes averaged up to 142% greater than the most widely grown variety, RR21. With farmer participation in the selection process in different agroecological micro-niches of Nepal, both yield potential and yield stability of wheat should increase significantly, thereby providing farmers with the economic means to sustain the current smallscale agriculture suited to the mountainous terrain.