Participatory varietal selection of potato using the mother & baby trial design: A gender-responsive trainer’s guide.

This guide aims to provide step-by-step guidance on facilitating and documenting the PVS dynamics using the MBT design to select, and eventually release, potato varieties preferred by end-users that suit male and female farmers ’different needs, diverse agro-systems, and management practices, as well as traders ’and consumers’ preferences

Yield Evaluation of Nutrient-rich Potato Clones in High Hill of Nepal

A study was conducted to evaluate the yield of nutrient-rich potato clones in high-hill districts: Dolakha and Jumla of Nepal during the years 2013 and 2014, respectively. Fourteen potato clones were tested as on-station and on-farm experiments at both districts, and those fourteen clones were compared to ‘Lady Rosita' and ‘Jumli Local' respectively as the check varieties in the first year experiment, 2013. Eight promising clones were selected from the first year experiment, and were evaluated and compared with same local varieties in the consecutive year, 2014. Two clones namely; CIP 395112.32 (19.3 tha-1) and CIP 393073.179 (17.8 tha-1) exhibited superior marketable tuber yield than that of ‘Lady Rosita'(14.2 tha-1) in Dolakha and five CIP clones namely; 395112.32 (25.5 tha-1), 393073.179 (22.5 tha-1), 394611.112 (20.9 tha-1), 390478.9 (19.9 tha-1) and 395017.229 (17.0 tha-1) showed higher marketable tuber yield than ‘Jumli Local'(14.5 tha-1). Based on two years' phenotypic and tuber yield result, clones CIP 395112.32 and CIP 393073.179 are recommended to potato growers at high hills of Nepal for commercial cultivation.Journal of Nepal Agricultural Research Council Vol.3 2017: 6-1

Multiple QTLs linked to agro-morphological and physiological traits related to drought tolerance in potato.

Dissection of the genetic architecture of adaptation and abiotic stress-related traits is highly desirable for developing drought-tolerant potatoes and enhancing the resilience of existing cultivars, particularly as agricultural production in rain-fed areas may be reduced by up to 50 % by 2020. The “DMDD” potato progeny was developed at International Potato Center (CIP) by crossing the sequenced double monoploid line DM and a diploid cultivar of the Solanum tuberosum diploid Andigenum Goniocalyx group. Recently, a high-density integrated genetic map based on single nucleotide polymorphism (SNP), diversity array technology (DArT), simple sequence repeats (SSRs), and amplified fragment length polymorphism (AFLP) markers was also made available for this population. Two trials were conducted, in greenhouse and field, for drought tolerance with two treatments each, well-watered and terminal drought, in which watering was suspended 60 days after planting. The DMDD population was evaluated for agro-morphological and physiological traits before and after initiation of stress, at multiple time points. Two dense parental genetic maps were constructed using published genotypic data, and quantitative trait locus (QTL) analysis identified 45 genomic regions associated with nine traits in well-watered and terminal drought treatments and 26 potentially associated with drought stress. In this study, the strong influence of environmental factors besides water shortage on the expression of traits and QTLs reflects the multigenic control of traits related to drought tolerance. This is the first study to our knowledge in potato identifying QTLs for drought-related traits in field and greenhouse trials, giving new insights into genetic architecture of drought-related traits. Many of the QTLs identified have the potential to be used in potato breeding programs for enhanced drought tolerance

A case study of potato germplasm enhancement using distant late blight resistant wild relatives

Improving potato late blight (LB) resistance is essential for ensuring food security, particularly using wild relatives endemic to Phytophthora infestans - prone regions. However, reproductive barriers can impede the transfer from potato wild relatives (PWR) to the cultivated genepool. This study sought to incorporate potentially novel LB resistance from wild diploid accessions of Series Piurana (S. chiquidenum, S. paucissectum, and S. piurae), Tuberosa (S. cajamarquense), and Megistracroloba (S. sogarandinum) into tetraploid potato. Trough rescue pollination, 699 diploid interspecific hybrids were obtained, of which 385 displayed LB resistance in two endemic environments. Based on a comprehensive evaluation, including assessing 2n pollen production, 14 diploid interspecific hybrids were selected to continue the introgression process. These pre-bred stocks were then used in interploidy (4x-2x) crosses to incorporate their LB resistance in the cultivated tetraploid background. Assessment of 1978 genotypes resulting from interploidy crosses under endemic disease pressure yielded 717 hybrids with moderate to high levels of LB resistance. Evaluation of pollen viability and ploidy revealed moderate fertility and predominantly tetraploid genotypes. Reassessment of LB resistance on this new subset of hybrids further identified 214 genotypes with sustained resistance. Among them, 12 tetraploid hybrids with low glycoalkaloid content, favorable agronomic and post-harvest attributes were identified as crossing-friendly stocks. Notably, 11 of these hybrids were derived from S. cajamarquense and one from S. sogarandinum. These promising 4x hybrids are now primed to be incorporated into potato breeding programs

Estudio del genoma de la yuca mediante las técnicas de RFLP y RAPD

IP 2228-07-003-92Incluye anexos

Total and individual carotenoid profiles in Solanum phureja of cultivated potatoes. 1: Concentrations and relationships as determined by spectrophotometry and HPLC.

Total and individual carotenoid concentrations were determined by spectrophotometry and HPLC, in raw tubers of a sample of 23 accessions of Solanum phureja potatoes taken at random from the world germplasm collection following its stratification on tuber flesh color. Lutein, zeaxanthin, violaxanthin, antheraxanthin and ß-carotene were detected in all accessions and three distinct patterns of carotenoid accumulation were evidenced by cluster analysis. Accessions in group 1 showed the highest concentrations of total carotenoids (1258–1840 µg 100 g-1 FW) comprised largely of zeaxanthin (658–1290 µg 100 g-1 FW) with very low or no presence of ß-carotene (below 5.4 µg 100 g-1 FW). Accessions in group 2 presented moderate total carotenoid concentrations with violaxanthin, antheraxanthin, lutein and zeaxanthin as the major carotenoids. Accessions in group 3 showed low concentrations of total carotenoids (97–262 µg 100 g-1 FW) and very low or no zeaxanthin, with lutein and violaxanthin as the predominant carotenoids and relatively high concentrations of ß-carotene (up to 27 µg 100 g-1 FW). Five accessions with significant concentrations of zeaxanthin were identified with the accession 703566 showing the highest concentration (1290 µg 100 g-1 FW). This value is to our knowledge higher than any value previously reported for potatoes, including those achieved through genetic modification. For the 23 S. phureja accessions, total carotenoid concentration was positively and significantly correlated with antheraxanthin and zeaxanthin concentrations, and negatively and significantly correlated with ß-carotene concentration

PL-4 (CIP596131.4): an Improved Potato Haploid Inducer

Dihaploid production from elite tetraploid cultivars is key to both traditional and novel breeding approaches that seek to simplify potato genetics. For this purpose, efficient and widely compatible haploid inducers (HIs) are needed. We compared PL-4, a new HI developed at the International Potato Center, to known HIs IvP101 and IvP35. By pollination of elite tetraploid breeding lines, we showed that PL-4 performed significantly better and had a homogeneous response regardless of the genetic background of the pistillate parents, on the most important efficiency traits-number of dihaploids per 100 fruits and haploid induction rate. Moreover, PL-4 exhibited a reduced proportion of hybrid seeds, a convenient trait for efficient screening. In this context, we recommend PL-4 as an enhanced HI for the potato breeding community