Nepal has released and registered a total of 623 genetically uniform (mono genotyped) varieties. These varieties were developed by both conventional and classical plant breeding, biotech-assisted plant breeding, and participatory plant breeding methods. However, these varieties have been shown to vary in their yield performance over the years and locations. Smallholder farmers dominate agriculture with 53% of the land-owning households with their land holding size of less than 0.5 ha in Nepal. Farmers are increasingly losing their own saved seeds. There have been impacts of weather variability, often modern crop varieties are not available to suit with these changing conditions. Farmers are looking for crop varieties that can better adapt to these changing conditions, and seeds of which can be saved for the next season planting. Evolutionary Plant Breeding (EPB), which creates and maintains a high degree of genetic diversity (i.e. polymorphic population), is a choice for breeders and farmers for accelerating the development of climate resilient and sustainably high-performance crop varieties. In 2015, the National Gene Bank in Nepal started an EPB program for the local rice variety, Jumli Marshi with the objective of enhancing genetic conservation through creating a dynamic gene pool. An evolutionary population can be compared to a living gene bank, not only in line with bringing greater yield stability, but also greater diversity in aroma, nutritional value and quality. Evolutionary populations have the potential to produce higher yields and perform better than their local or improved counterparts in adverse, or stress conditions. Under stress conditions, evolutionary populations have also been shown to be more resistant to weeds, diseases and pests damage than homogenous crop populations. Based on the source of diversity used in EPB, two different types of populations- Composite Cross population, and Composite Mixtures, population are developed. With the exception of Europe, and only for some crops, existing seed policies do not favor such populations. Therefore, there is a need to revise seed regulations in order to allow the cultivation of a higher degree of genetic diversity.

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Photoperiod responsive flowering and growth habit might have played a key role in domestication of lablab bean (Lablab purpureus) and currently shifting its cultivation from intercropping to monoculture. Most of the landraces of lablab bean exhibit photoperiod sensitivity in flowering and indeterminate growth habit. A cross was made between GNIB21 and GP189 which are phenotypic extremes for photoperiod responsive flowering. The F1 hybrid exhibited dominant traits like indeterminate growth habit and photosensitive flowering endowed from male parent. Segregation pattern of 3:1 in F2 generation indicated monogenic recessive nature of photoperiod insensitive flowering. Bulk segregant analysis in F2 population revealed association of PvTFLy1, a locus governing determinate growth habit in lablab bean, with photoperiod responsive flowering where an amplicon of 300 bp was observed in photo sensitive GP189 while it was absent in photo insensitive variety GNIB21. Significant ÷2 test indicated coupling phase of linkage between PvTFLY1 and photoperiod responsive flowering. Linkage analysis placed PvTFLY1 at the distance of 19.23 cM from the locus governing photoperiod responsive flowering. The linkage between growth habit and photoperiod responsive flowering in common bean, soybean and Indian bean suggest that these traits may be governed by mutation or deletion of E3 (or GmPhyA3) and Dt1 homologs in Indian bean. Information available on characterized genes for photoperiod responsive flowering and determinate growth habit from common bean, soybean and other related legumes may be utilized for isolation, characterization, mapping and molecular dissection of genes involved in regulation of photoperiod responsive flowering in Indian bean.

Background Biologically important curcuminoids viz curcumin, demethoxycurcumin, and bisdemethoxycurcumin in turmeric rhizome have several health benefits. Pharmaceutical industries synthesize curcuminoids manipulating gene expressions in vitro or in vivo because of their medicinal importance. In this experiment, we studied the gene expressions involved in the curcuminoid biosynthesis pathway in association with curcuminoid yield in turmeric rhizome to study the impact of individual gene expression on curcuminoid biosynthesis. Results Gene expressions at the different growth stages of turmeric rhizome were association tested with respective curcuminoid contents. Gene expression patterns of diketide-CoA synthase (DCS) and multiple curcumin synthases (CURSs) viz curcumin synthase 1 (CURS1), curcumin synthase 2 (CURS2), and curcumin synthase 3 (CURS3) were differentially associated with different curcuminoid contents. Genotype and growth stages showed a significant effect on the gene expressions resulting in a significant impact on curcuminoid balance in turmeric rhizome. DCS and CURS3 expression patterns were similar but distinct from CURS1 and CURS2 expression patterns in turmeric rhizome. DCS expression had a significant positive and CURS3 expression had a significant negative association with curcumin, demethoxycurcumin, bisdemethoxycurcumin, and total curcuminoid in turmeric rhizome. CURS1 expression had a negative association with curcumin whereas CURS2 expression showed a positive association with demethoxycurcumin. Conclusions The effects of DCS and CURS expressions are not always positive with different curcuminoid contents in turmeric rhizome. DCS expression has a positive and CURS3 expression has a negative association with curcuminoids. CURS1 and CURS2 are also associated with curcumin and demethoxycurcumin synthesis. This mechanism of co-expression of diketide-CoA synthase and multiple curcumin synthases in turmeric rhizome has a significant effect on curcuminoid balance in different turmeric cultivars. Further experiment will explore more insights; however, association-based test results from this experiment can be useful in improving curcuminoid yield in turmeric rhizome or in vitro through the application of genetic engineering and biotechnology. Graphical abstract Associating gene expressions with curcuminoid biosynthesis in turmeric

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Field trials of rice and bean dynamic mixtures were carried out in low input and hill farming systems of Nepal from 2019 to 2021 to improve productivity and resilience. The rice trials were conducted in two locations (Jumla and Lamjung) and those on bean in Jumla, using a randomized complete block design with three replications. Dynamic mixtures were constructed from landraces, improved varieties and breeding lines for both crops. A total of 48 bean entries were used in Jumla, whereas 56 and 66 rice entries were used to make location-specific dynamic mixtures in Lamjung and Jumla, respectively. They were formed by mixing diverse varieties as a strategy to maintain a broad genetic base. Farmers (men and women) and technicians selected from the most complex mixture and the selections were added to the trials starting from second year. In rice, some mixtures and selections from the mixtures gave grain yield comparable to the improved check and higher than the local checks. In the case of bean, differences between entries were not significant but some of the selections received a high preference score. Overall, the dynamic mixtures appear as a reliable material for sustainable increase in yield in the low input and hill farming system of Nepal.

Turmeric (Curcuma longa L.) is an economically important spice and medicinal plant for production of curcuminoids, oleoresin, essential oil which are used in pharmaceutical and cosmetics industries. Presence of these contents in turmeric determine its quality. Average productivity and quality of turmeric is not satisfactory because of the poor genetic materials and non-availability of quality materials. Conventional clonal selection takes long time and slow progress to achieve the same level of quality improvement than molecular or biotechnological approaches. Use of molecular markers, transcriptome sequencing, real time PCR approaches can be applied as a supplement to conventional methods of breeding through clonal selection and advancing elite genotypes. In this paper, we will discuss in short about the use of different approaches developed for quality improvement in turmeric.Keywords: Clonal selection; Curcuminoids; Molecular approach; Quality; Turmeric IntroductionTurmeric (Curcuma longa L.) (2n=3x=63) belonging to the family Zingiberaceae is an economically important spice and medicinal plant for production of curcumin, oleoresin, essential oil which are used in pharmaceutical and cosmetics industries. Traditionally turmeric is known as Haldi in India, Besar in Nepal and is under extensive cultivation in South Asian countries for medicinal, religious, culinary purposes and also as a cosmetic and dye. Dry recovery (curing percentage), curcumin and oleoresin contents determine the quality of turmeric and high variability has been observed in turmeric germplasm with respect to these characters [1]. Turmeric powder obtained from rhizomes of C. longa is extensively used as a spice, food preservative, natural dye in food industry and in cosmetics and drugs [2]. Curcuminoid, a phenylpropanoid derivative, is a mixture of curcumin (50-60 % of the curcuminoids), demethoxycurcumin and bisdemethoxycurcumin which imparts yellow colour to turmeric [3]. The medicinal properties of curcuminoids as anti-inflammatory, anti-oxidant, antimutagenic, anti-diabetic, anti-bacterial, hepatoprotective and expectorant are reported extensively. It is also well known in treating conditions ranging from arthritis and inflammation to Alzheimer's disease and cancer [2]. Because of widespread multipurpose use of this medicinal herb in pharmacological industry, spice industry and other culinary purpose use, quality improvement for enhanced phyto-constituents production in turmeric is of great importance in the present context. Need for Crop Improvement in TurmericAlthough India is a leading producer of turmeric and few high yielding cultivars are available in this crop, the average productivity and quality are not satisfactory. Major problems are non-availability of requisite high yielding genotype, slow multiplication rate, low curcumin and essential oil content in available cultivars and loss due to disease during cultivation and storage. Crop improvement work in turmeric is so far confined mostly to clonal selection by exploiting...

A field experiment was conducted in popular carrot cultivar Nepa Dream using randomized complete block design (RCBD) with four replications for evaluating the effects of ten different treatments of soil conditioner in combination with organic and inorganic fertilizers on root growth and soil productivity. Soil samples from each microplot were also analyzed for soil texture, pH, organic matter, total nitrogen, available nitrogen, total phosphorus and total potassium before sowing and after harvest. Effects on soil was not significant in the single season experiment but effects of the treatments on the carrot root growth and production was significant. For higher root yield and biological yield, treatments Soil Conditioner +Micronutrient (Double Dose)+1/2 Recommended Dose of Fertilizer +1/2 Farm Yard Manure (T10) followed by Soil Conditioner +Micronutrient (Normal)+1/2Recommended Dose of Fertilizer +1/2 Farm Yard Manure (T7), and Recommended Dose of Fertilizer Full (T2) were found better whereas treatment T10 was found closer to T2 and Soil Conditioner +Micronutrient  (Double Dose)+Farm Yard Manure Full (T9) which showed higher mean performances for root diameter, cortex diameter and root length of carrot. In contrast, total soluble sugar as % brix was found less in the treatments involving one or more combinations of conditioner whereas highest for Farm Yard Manure and Recommended Dose of Fertilizer treatments either alone or in combination.  Thus, use of normal dose of GMT™ soil conditioner along with ½ Recommended Dose of Fertilizer and ½ Farm Yard Manure (T7) can be used as an alternative to T2 for higher carrot production which also can reduce the use of commercial inorganic fertilizers for improving soil fertility status. For organic carrot production at low cost, T9 can also be used as an alternative to other combinations of chemical fertilizers.