American Journal of Potato Research最新文献

The robust root system of Solanum chacoense Bitt. (Chc) offers potential for improving nutrient use efficiency in potato breeding. This study investigated methods and traits associated with nitrogen uptake efficiency (NUpE) to facilitate the selection of superior Chc parents for developing improved potato varieties for two consecutive growing seasons. The objectives were to (1) determine correlations between phenotypic traits and nitrogen use efficiency (NUE) components in Chc genotypes, (2) evaluate the reliability of a greenhouse-based screening method for predicting field performance of NUE-related traits in Chc, and (3) identify Chc genotypes with superior NUpE for introgression into cultivated potato (S. tuberosum, Tbr) to improve NUE. Eight Chc genotypes and three Tbr cultivars (‘Atlantic’, ‘Elkton’, and ‘Harley Blackwell’) were grown in greenhouse and field environments under two nitrogen (N) application rates (84 and 168 kg ha⁻¹). Above-ground dry weight (AGDW), root and stolon dry weight (RSDW), tuber dry weight (TBDW), and total dry weight (TDW) were measured and correlated with N accumulation, NUpE, nitrogen utilization efficiency (NUtE), and NUE. AGDW and TDW in Chc were positively correlated with N accumulation, NUpE, and NUE in both environments over two years. Positive correlations for N accumulation and NUpE between greenhouse and field performance were observed for Chc genotypes in 2015, supporting the reliability of the greenhouse screening method. One Chc genotype (C-9) exhibited superior NUpE compared to the Tbr cultivar ‘Atlantic’ in both environments in the second season. These findings demonstrate the potential of using superior NUpE Chc parents for introgression into Tbr to develop potato cultivars with enhanced NUE.

Potato cytoplasm type has been linked to fertility and disease resistance traits, making it an important consideration in potato breeding programs. Previous research has developed genetic markers to distinguish the six different cytoplasm types (P, T, W, D, A, and M). These markers were used to identify the different cytoplasm types present in the USDA-ARS Potato Variety Development Program for the Eastern U.S. Tetraploid families were predominantly type T, with a significant number of type D. Diploid families had a large proportion of type P, reflecting the contribution of Solanum tuberosum Group Phureja. Primary dihaploids, being derived from tetraploids, had a similar cytoplasm composition as the tetraploid families, predominantly type T and D. As has been previously reported, cytoplasm type was correlated with male fertility. The USDA-ARS Potato Variety Development Program for the Eastern U.S. will use the cytotype data to direct breeding efforts going forward.

The growth and yield of any crop are largely dependent on intercepted photosynthetically active radiation (IPAR), and the efficiency of that crop to convert it into dry matter, i.e. radiation use efficiency (RUE). In this context, two years (2018–2019 and 2019–2020) of field experiments were carried out, to study the seasonal distribution of PAR and its effect on the growth, yield attributes, and RUE of potato var. Kufri Jyoti. Four levels of irrigation with irrigation water depth (IW): cumulative pan evaporation (CPE) (IW: CPE = 0.4, 0.8, 1.2, and 1.6) and three levels of potassium (K₂O: 100, 150, and 200 kg ha⁻¹) were applied as the main plot and sub-plot factors respectively in the experiment which was laid out in split-plot design with three replications. Seasonal variation of all components of PAR was studied and RUE was assessed. Furthermore, correlations were established between these variables and various growth and yield parameters. The results revealed that the incident PAR use efficiency (PARUE) varied from 1.12 to 3.31 g MJ⁻¹ in 2018-19 and from 1.58 to 2.53 g MJ⁻¹ in 2019-20 whereas the intercepted PARUE varied from 3.64 to 8.35 g MJ⁻¹ in 2018-19 and from 4.34 to 6.24 g MJ⁻¹ in 2019-20. APAR (%) exerted a positive and highly significant correlation whereas reflected PAR (RPAR) (%) showed a significantly strong negative correlation with the growth and yield of potatoes.

The Rx1 and Rx2 genes from wild potato species confer extreme resistance to potato virus X (PVX). Accurate genotyping is essential for their integration into breeding programs. We developed tetra-primer ARMS-PCR markers targeting SNPs (G2515C in Rx1 and C2445G in Rx2) in the LRR regions to distinguish resistance alleles. These markers effectively genotyped 50 tetraploid potato varieties, identifying 16 as Rx1 heterozygous, 5 as Rx2 heterozygous, and 29 as homozygous susceptible consistent with phenotypic data. The T-ARMS-PCR outperformed existing markers and enabled efficient duplex detection of both genes. Although no homozygous resistant varieties were found, artificial DNA mixtures validated marker reliability for homozygous and heterozygous resistance detection. To our knowledge, this is the first use of T-ARMS-PCR for Rx1/Rx2 genotyping, offering a high-throughput tool for marker-assisted selection in developing PVX-resistant cultivars.

Finding supplementary treatments with high sprout suppression efficacy is necessary for maintaining optimum potato (Solanum tuberosum L.) tuber quality in storage. The objective of this research was to determine the efficacy of sweet orange (Citrus sinensis), spearmint (Mentha viridis), and oregano (Origanum vulgare) essential oils (EOs) as sprout suppressor treatments and optimize their application methods. EOs were applied either thermally, using cv. Russet Burbank and cv. Ranger Russet tubers at different stages of dormancy, or applied via air-wicking method using mini tubers of cv. Russet Burbank. After the treatments, sprout growth of tubers was monitored and different tuber tissues were collected for biochemical analysis in the air-wicking study. Overall, thermal application of EOs was an effective method, and oregano EO exhibited higher efficacy for sprout control. When applied using an air-wick method, temporary sprout suppression until 6-weeks and lower reducing sugar content in bud tissues were observed with spearmint EO. Increase in chlorogenic acid content and activity of antioxidant enzyme was observed in primary bud tissues with oregano EO treatment, indicating a stress induction response. Overall, EO treatments impacted sugar metabolism, antioxidant enzymes, and secondary metabolites, which significantly influence the sprouting of potato tubers.

Potato growers and processors throughout the Pacific Northwest have observed that extensive periods of smoke exposure from summer wildfires can have negative effects on potato crops (Solanum tuberosum L). Replicated field studies were conducted during 2022 and 2023 to document the impact of smoke exposure on yield, grade and storability of three russet potato cultivars (‘Russet Burbank’, ‘Clearwater Russet’, ‘Alturas’). Potato plants were treated from July 10 to August 18 each year in clear plastic-covered hoop house enclosures between 6:00 and 9:00am MST, before rising temperatures within the enclosures would cause heat stress. The fuel used to generate smoke consisted of a mixture of hard and soft wood tree species. Tubers were harvested in mid-September, graded, and samples placed into storage at 9^oC for 6 months. Yield, quality and decay after storage were used to calculate revenue and smoke impact using a potato processing contract. Potato plants exposed to smoke did not exhibit any visual symptoms and did not senescence earlier than plants not exposed to smoke. Smoke exposure caused a decline in proportion of U.S. No 1 tubers (p = 0.09). and a slight increase in the proportion of cull tubers (p = 0.08). The effect of smoke on cull production was more apparent during the 2022 trial when daytime high temperatures were often above the level considered optimum for potato growth, and less apparent in the more moderate conditions experienced during 2023. A similar effect was seen on specific gravity, with smoke treatment causing a significant decline in 2022 but not in 2023. Smoke treatments had no impact on weight loss but decreased decay after six months of storage. The three cultivars tended to exhibit different responses to smoke exposure in terms of proportion of < 113 g and > 170 g tubers (p = 0.06 and 0.04, respectively). Alturas and Russet Burbank exhibited no change in the percentage of < 113 g and > 170 g tubers due to smoke treatment in both 2022 and 2023. In contrast, Clearwater Russet showed an increase in < 113 g tubers in 2022 due to smoke treatment and a decline in 2023. Clearwater Russet also exhibited a significant decline in the proportion of yield that was > 170 g in response to smoke treatment in 2022, but no effect in 2023. The impact of smoke on crop revenue was variable, ranging from a 20% decrease to a 17% increase. It is unclear whether cultivar selection could be used as a tool to reduce the risk of losses due to wildfire smoke exposure.

Most of the germplasm in the US Potato Genebank is stored as seedlots with varying levels of genetic diversity both within and among them. Therefore, we aim to determine the most efficient method for measuring this diversity. A seedlot from each of four species of tuber-bearing Solanum representing different ploidies and breeding systems (S. fendleri, jamesii, microdontum, and sucrense), was sown to produce 24 individuals. Additionally, three types of bulk samples were created. These samples were genotyped using Genotyping By Sequencing (GBS) with enhanced read depth (> 100 × per sample). We introduced the shorthand term “Cap2” for loci where the two SNP alleles, known to be present among individuals, were detected in the bulk (i.e., Captured). After excluding loci with missing calls or one fixed allele, 100% of the remaining loci were considered potentially Cap2. Cap2 was evaluated for loci categorized by different combinations of average minor allele frequencies (MAF) among individuals and read depth of the bulks. For loci with at least 5% MAF and a minimum of 100 reads, the average Cap2 for individuals was 81%, while all bulks, irrespective of species or bulking method, showed a Cap2 bulk average of 100% (average of 8,000 loci with an average of 144 reads). While genotyping a large number of individuals in a seedlot provides a precise measure of diversity, bulking DNA of many individuals followed by assessment of only the high-read loci with a MAF of at least 5% offers an efficient and optimized method for detecting the genetic landscape of a population with just a single sample.

The 4Rs of nutrient management is an initiative to balance economics with sustainability. The objective was to evaluate individual and stacked 4R practices on potato (Solanum tuberosum L.) profitability. Treatments included all combinations of two nitrogen (N) sources (urea or polymer coated urea [PCU]), two rates (82 or 100%), and/or two timing/placements (at emergence or split-applied). Gross income and net profit were determined using yields, market sale data, and costs. Total gross income was greatest for PCU split applied and PCU at emergence in 2020 and 2023, respectively. Gross income and net profit were higher for the full rate for PCU compared to urea. The detrimental effect of the reduced rate disappeared with PCU, but not urea. A reduced rate of PCU was similar to a full rate of split applied urea. These data suggest that PCU is a profitable N source for potato even at reduced rates.