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Low-temperature related abiotic stress is an important factor affecting winter survival in lowland switchgrass when grown in northern latitudes in the United States. A better understanding of the genetic architecture of freezing tolerance in switchgrass will aid the development of lowland switchgrass cultivars with improved winter survival. The objectives of this study were to conduct a freezing tolerance assessment, generate a genetic map using single nucleotide polymorphism (SNP) markers, and identify QTL (quantitative trait loci) associated with freezing tolerance in a lowland × upland switchgrass population. A pseudo-F 2 mapping population was generated from an initial cross between the lowland population Ellsworth and the upland cultivar Summer. The segregating progenies were screened for freezing tolerance in a controlled-environment facility. Two clonal replicates of each genotype were tested at six different treatment temperatures ranging from −15 to −5°C at an interval of 2°C for two time periods. Tiller emergence (days) and tiller number were recorded following the recovery of each genotype with the hypothesis that upland genotype is the source for higher tiller number and early tiller emergence. Survivorship of the pseudo-F 2 population ranged from 89% at −5°C to 5% at −15°C with an average LT 50 of −9.7°C. Genotype had a significant effect on all traits except tiller number at −15°C. A linkage map was constructed from bi-allelic single nucleotide polymorphism markers generated using exome capture sequencing. The final map consisted of 1618 markers and 2626 cM, with an average inter-marker distance of 1.8 cM. Six significant QTL were identified, one each on chromosomes 1K, 5K, 5N, 6K, 6N, and 9K, for the following traits: tiller number, tiller emergence days and LT 50 . A comparative genomics study revealed important freezing tolerance genes/proteins, such as COR47, DREB2B, zinc finger-CCCH, WRKY, GIGANTEA, HSP70, and NRT2, among others that reside within the 1.5 LOD confidence interval of the identified QTL.

The lowland ecotype of switchgrass has generated considerable interest because of its higher biomass yield and late flowering characteristics compared to the upland ecotype. However, lowland ecotypes planted in northern latitudes exhibit very low winter survival. Implementation of genomic selection could potentially enhance switchgrass breeding for winter survival by reducing generation time while eliminating the dependence on weather. The objectives of this study were to assess the potential of genomic selection for winter survival in lowland switchgrass by combining multiple populations in the training set and applying the selected model in two independent testing datasets for validation. Marker data were generated using exome capture sequencing. Validation was conducted using (1) indirect indicators of winter adaptation based on geographic and climatic variables of accessions from different source locations and (2) winter survival estimates of the phenotype. The prediction accuracies were significantly higher when the training dataset comprising all populations was used in fivefold cross validation but its application was not useful in the independent validation dataset. Nevertheless, modeling for population heterogeneity improved the prediction accuracy to some extent but the genetic relationship between the training and validation populations was found to be more influential. The predicted winter survival of lowland switchgrass indicated latitudinal and longitudinal variability, with the northeast USA the region for most cold tolerant lowland populations. Our results suggested that GS could provide valuable opportunities for improving winter survival and accelerate the lowland switchgrass breeding programs toward the development of cold tolerant cultivars suitable for northern latitudes.

Goat marketing study was conducted in eleven districts with the objectives of exploration the existing goat marketing system in western hills of Nepal. The methodology of the study was households survey, Rapid Marketing Appraisal and use of secondary data. Some of the marketing centers are at the village level, catchments, terminal level markets and district headquarters. There are some marketing agents dealing with the goat marketing from village to the municipalities. Goat marketing agents mainly found farmers and middlemen at the village level and catchments markets. In terminal markets mainly wholesalers and middlemen were involved where as in district headquarters and municipalities middlemen, wholesalers and butchers were dealing the goat business. 59.3% respondents believed that middlemen visit in the village for goat marketing. Almost all farmers sell their goats on the basis of estimated price. Major constraints on goat marketing were lack of public goat marketing centres, lack of communications about goat marketing and lack of infrastructure etc in all the domestic markets. In the western hills of Nepal main goat marketing centre was found in Pokhara sub municipality where traders/whole sellers bring their goats to sale from different catchments. Government has the provision of establishing new goat marketing centers in each VDCs and district headquarters.

Sainfoin is a highly nutritious non-bloating leguminous forage crop of temperate regions. Despite non-bloating properties, its use in pastures was limited due to low dry matter yield (DMY), lack of persistence in the mixed pasture and slow regrowth. The paradigm then shifted when new sainfoin cultivars planted in mixtures with alfalfa reduced 98% bloat incidence in ruminants. Two experiments were conducted to determine the compatibility of sainfoin with grass and alfalfa. Exp. I was established by drilling alfalfa cv. Longview and orchardgrass cv. Kayak with new sainfoin populations in alternate or cross-seeding rows under irrigated and unirrigated conditions in Lethbridge, AB. Exp. II was established by drilling sainfoin populations in mixture with alfalfa cultivars in alternate rows under irrigation. Dry matter yield (DMY) and botanical composition (DM basis) were observed for both experiments. In Exp. I, monoculture orchardgrass produced the least DMY compared to the mixtures at both growing conditions and over all growing seasons. Alfalfa-sainfoin mixture yielded higher under irrigation and less under unirrigated conditions relative to alfalfa monoculture. The percentage DMY contribution of sainfoin in alfalfa-sainfoin mixtures decreased but increased in sainfoin-orchardgrass mixtures over successive harvests under both environments. In Exp. II, we observed new sainfoin populations mixed with alfalfa cvs. Beaver and Longview yielded greater (P< 0.05) than their corresponding monocultures and this increase was not associated with the proportion of the species in the mixture suggesting new sainfoin populations are as productive as alfalfa.

High winter mortality limits biomass yield of lowland switchgrass (Panicum virgatum L.) planted in the northern latitudes of North America. Breeding of cold tolerant switchgrass cultivars requires many years due to its perennial growth habit and the unpredictable winter selection pressure that is required to identify winter‐hardy individuals. Identification of causal genetic variants for winter survivorship would accelerate the improvement of switchgrass biomass production. The objective of this study was to identify allelic variation associated with winter survivorship in lowland switchgrass populations using bulk segregant analysis (BSA). Twenty‐nine lowland switchgrass populations were evaluated for winter survival at two locations in southern Wisconsin and 21 populations with differential winter survivorship were used for BSA. A maximum of 10% of the individuals (8–20) were bulked to create survivor and nonsurvivor DNA pools from each population and location. The DNA pools were evaluated using exome capture sequencing, and allele frequencies were used to conduct statistical tests. The BSA tests revealed nine quatitative trait loci (QTL) from tetraploid populations and seven QTL from octoploid populations. Many QTL were population‐specific, but some were identified in multiple populations that originated across a broad geographic landscape. Four QTL (at positions 88 Mb on chromosome 2N, 115 Mb on chromosome 5K, and 1 and 100 Mb on chromosome 9N) were potentially the most useful QTL. Markers associated with winter survivorship in this study can be used to accelerate breeding cycles of lowland switchgrass populations and should lead to improvements in adaptation within USDA hardiness zones 4 and 5.

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