American Journal of Potato Research最新文献

Potato virus Y (PVY) is an important pathogen in seed potato production that may cause seed lots to be downgraded or rejected for certification. A study was conducted to determine if mother seed tuber size influences the prevalence of PVY within a seed sample during evaluations of seed-borne infection in a grow-out. The trial was conducted using Russet Norkotah (two growing seasons) and Umatilla Russet (one growing season). Several seed tuber size categories were utilized: (a) single drop (42 to 112 g), (b) small (113 to 169 g), (c) medium (170 to 282 g), (d) large (283 to 340 g), and (e) a mixed sample (year one only). The trial was planted in Kimberly, ID in a randomized block design. Visual evaluations for foliar PVY symptoms were conducted when plants were approximately 30 cm tall and total yield and yield profile evaluated at harvest. Visual foliar seedborne PVY incidence did not significantly differ among mother tuber size categories, for either year, cultivar, or seedborne PVY level. Seed tuber size treatments ranged from 38 to 43% visual PVY incidence in Umatilla Russet, 68 to 73% in Russet Norkotah in year one, and 5 to 6% in Russet Norkotah in year two. Differences in yield and yield size profile were observed, however, may be attributed to mother seed tuber size rather than PVY level. It appeared PVY was evenly distributed within seed samples and various mother tuber sizes and types did not affect the evaluation of seed-borne infection.

Blackberry is a tablestock variety with uniquely deep purple skin and flesh. The tubers have an attractive, uniform, round shape with common scab resistance and low incidence of internal defects. It also carries the Rysto marker for extreme resistance to potato virus Y. When baked or microwaved, the tuber flesh is a brilliant deep purple with an enjoyable mild taste. It was selected in 2011 from a cross between two breeding lines COMN07-W112BG1 and MSU200-5PP. Although primarily oriented towards the fresh market, Blackberry is an all-purpose variety that also has the ability to chip out of the field. Yields are high under irrigated conditions and specific gravity averaged 1.068 in on-farm trials in Michigan.

Manistee is a round white chip-processing potato (Solanum tuberosum) variety developed for long-term storage. Evaluated as MSL292-A, Manistee is a selection from a cross between Snowden and the chip-processing breeding line MSH098-2. The tubers of Manistee are compressed, round with shallow eyes and early to mid-season maturity. Field testing and on-farm trials show that this variety has high yield potential with specific gravity comparable to Snowden and similar to better tolerance to blackspot bruise. Manistee was formally released in 2013 and has demonstrated reliable and excellent long-term storage chip-processing quality up to eight months post-harvest which extends the chip-processing storage season beyond Snowden. Furthermore, preliminary studies with Manistee, Snowden, Lamoka and Pike tuber disks demonstrated that Manistee started the wound healing process faster than Lamoka and Pike and slightly faster than Snowden which supports observations of stable and reliable commercial storage of the tubers for chip-processing.

Petoskey is a high specific gravity round white chip-processing potato variety with resistance to common scab (Streptomyces scabies). It was selected from a cross between Beacon Chipper and the breeding line MSG227-2, and designated MSV030-4 during the trialling phase of its development. This variety has high yield potential with attractive round, uniform tubers with netted skin. Five years of field testing in Michigan demonstrate that yield of Petoskey is similar to Snowden with higher specific gravity averaging 1.089. Out-of-the field chip scores were comparable to Snowden while Petoskey chip scores outperform Snowden in long-term storage trials at eight months post-harvest. Petoskey has a medium upright canopy and a mid to full season maturity with excellent long-term storage chip-processing quality. This variety has performed well in Michigan in on-farm trials and multistate national SNAC trials. Formally released in 2019, Petoskey is a comparable alternative to Snowden with strong resistance to common scab. Producers can expect higher specific gravity and longer storage potential than Snowden with high chip-processing quality up to eight months post-harvest.

Mackinaw is a disease resistant round white chip-processing potato with resistance to potato virus Y (PVY), late blight (Phytophthora infestans), and tolerance to common scab (Streptomyces scabies). Mackinaw also carries the TG689 marker for the H1 resistance gene to golden cyst nematode (Globodera rostochiensis) race Ro1. Designated as MSX540-4 during the trialling phase of its development, it was selected from a cross between the cultivars Saginaw Chipper and Lamoka. Field testing in Michigan show that this variety has average yield potential, similar to Snowden, with high specific gravity averaging 1.087. Mackinaw has a strong vine with a mid- to late-season maturity, producing a large percentage of A-sized tubers with a low incidence of internal defects and excellent long-term storage chip-processing quality. Mackinaw performed well in on-farm trials in Michigan and in multistate SNAC trials showing broad adaptation, especially in the northern tier states. Formally released in 2017, Mackinaw offers a unparalleled combination of disease resistance, long-term storage potential, and excellent chip-processing quality out of the field and out of long-term storage.

The availability of disease-free, high-quality seed material is crucial for improving potato productivity in India. Microplants of potato, being disease-free and pest-free, are used to produce minitubers when planted in various media, including soil and soilless. The study was conducted in an insect-proof net house to evaluate the performance of microplants of two potato varieties; Kufri Pukhraj and Kufri Himalini grown in soil and soilless media (cocopeat based media). Initial growth observations (35 days after planting) indicated that soilless led to better vegetative growth. However, at 55 and 70 days after planting, soil-grown plants exhibited more growth. Yield parameters such as total tuber number and tuber weight per square meter showed that Kufri Pukhraj outperformed comparative to Kufri Himalini. While observing total number of tubers in media, soilless yielded lesser tuber numbers and dry matter than soil. Significantly higher value of Harvest Index was obtained from soilless than the soil. There is marked increase in the net income and benefit cost ratio by growing microplant in soil (6.95) which was 4.54 times less in microplant grown in soilless culture under insect proof net house. The technology has a huge potential for adoption by small farmers for maintaining the quality of their own seed, where a smaller net house will enable them to harvest the larger number of tubers. The technology shows significant potential for adoption by small farmers, allowing them to maintain high seed quality through soilless and increase tuber yields in smaller net houses (Soil).

Solanum fendleri (fen) is one of two wild potato species native to the USA. The US Potato Genebank has 269 samples, over 90% of which were collected by the authors in annual expeditions to the states of Arizona, New Mexico, and Texas since 1992. For the ultimate in efficiency for germplasm representation of a species in the genebank one would: (1) acquire many population samples from the broadest possible eco-geographic representation of the range, (2) identify the minimum number of populations that collectively capture the maximum amount of diversity (a core subset), (3) identify the minimum number of individuals which, when combined as parents, collectively capture the maximum genetic diversity in a single new synthetic population. In 2016 we published a recommended core subset of fen from the USA. In 2020 we reported the discovery of a single very large “mega-population” of fen near Tucson, AZ that by itself could be considered a core subset of the species, capturing most of the known USA fen genetic diversity. We further optimized sampling of that mega-population site with more intensive sampling as 160 dispersed individuals, genotyping them at 32 K GBS loci, removing redundant individuals and selecting only 38 plants that capture 93% of the allele diversity and 71% of unique alleles, and then intermating those 38 plants. This study is presented as a model for composing the ultimate genebank sample of a species– the richest and most efficient representation of fen diversity in the USA packed into a single seedlot for sharing with researchers, breeders, and other genebanks.

Bacterial wilt or brown rot caused by Ralstonia solanacearum is among the most destructive diseases of potato in tropical highlands worldwide. There are no completely wilt-resistant varieties, but growers can reduce losses by planting partially resistant or tolerant potatoes. We screened the popular tropical potato cv. ‘Granola’ for bacterial wilt resistance under controlled conditions. Granola plants inoculated with high doses of R. solanacearum IIB-1 (Race 3 biovar 2) had reduced wilt disease progress relative to susceptible control cv. ‘Russet Norkotah’. Although the pathogen did colonize Granola plants, it reached significantly lower population sizes in Granola stems, stolons, and especially tubers than in those of Russet Norkotah. These results suggest that Granola has some tolerance to bacterial wilt, likely mediated by suppression of bacterial colonization. Thus, Granola could be a useful parent for tropical potato breeding programs.