Seed Borne Late Blight of Potato

Planting of potato seed pieces infected with Phytophthora infestans can lead to the introduction of late blight within a planting. When infected seed pieces are planted, there are three resulting scenarios: (i) a healthy plant emerges, (ii) no plant emerges because of the rapid decay of the seed piece, or (iii) a symptomatic plant emerges. A major factor favoring stand establishment and seed transmission is the severity of seed piece infection. When infection is severe, stand is compromised and transmission rate is low. When infection is mild, the plant emerges before the seed piece decays and, in some instances, the pathogen makes its way from the seed piece to the plant where a stem lesion is formed. Diseased seed tubers are the principle source of late blight inoculum for infection of healthy seed pieces. Treatment of infected or blighted seed tubers with a seed dressing with activity against P. infestans is not a viable tactic because the products are ineffective against established infections. Conversely, treatment of healthy seed pieces provides a high level of protection against late blight spores that are spread during the seed handling and planting operations. Optimum effectiveness is achieved when products are applied immediately following cutting, as none are effective against established infections. Seed treatment reduces the risk of seed transmission of late blight and enhances stand establishment and plant vigor. This tactic should be an important component of an integrated late blight management program. Accepted for publication 16 January 2002. Published 29 January 2002.

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Performance of Different Size True Potato Seed Seedling Tubers at Khumaltar

Nepal Agriculture Research Journal ◽

10.3126/narj.v6i0.3341 ◽

1970 ◽

Vol 6 ◽

pp. 35-38

Author(s):

Ram C Adhikari

Keyword(s):

Late Blight ◽

Ground Cover ◽

Tuber Size ◽

Potato Seed ◽

True Potato Seed ◽

Seed Tubers ◽

Research Journal ◽

Size Tuber ◽

Cut Seed ◽

Cut Seed Tubers

A field study was carried out at Khumaltar-Lalitpur, during 2002-2004 to evaluate and comparethe performance of different sizes of seedling tubers (1-5 g, 5-10 g, 10-20 g and 20-40 g) of truepotato seed (TPS) with whole and half cut seed tubers of Desiree of 20-40 g size at 60- × 25-cmspacing. Percent emergence, plant height, ground cover by foliage, stems/plant, number of tubersper plant, marketable and total yields were significantly increased with the increase in seedlingtubers weight as compared to whole and half cut seed tubers of Desiree. Late blight(Phytophthora infestans L.) disease was quite low in the TPS crops than Desiree. Both wholeand half cut seed tubers of Desiree produced significantly higher average per tuber weight.Uniformity of the tubers harvested from different sizes of seedling tubers was statisticallysimilar and tubers from Desiree were statistically uniform as compared to seedling tubers. Thethree years result suggests that more than 1 g size seedling tubers can be successfully used forpotato production as from the seed tubers of any standard variety.Key words: Desiree; seedling tuber; tuber size; tuber yieldDOI: 10.3126/narj.v6i0.3341Nepal Agriculture Research Journal Vol.6 2005 pp.28-34

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Transmission of Phytophthora infestans from Infected Potato Seed Tubers to Emerged Shoots

Plant Disease ◽

10.1094/pdis-94-1-0018 ◽

2010 ◽

Vol 94 (1) ◽

pp. 18-23 ◽

Cited By ~ 11

Author(s):

Dennis A. Johnson

Keyword(s):

Late Blight ◽

Phytophthora Infestans ◽

Fine Sand ◽

Russet Burbank ◽

Potato Seed ◽

Infected Seed ◽

Seed Tubers ◽

Moist Environment ◽

Soil Level ◽

Spring Planting

Transmission of Phytophthora infestans from infected seed tubers to emerged potato sprouts, infectivity of sporangia deposited on whole tubers before burial in soil, and infectivity of sporangia in a loamy fine sand to leaflets were investigated in the greenhouse under simulated spring planting conditions of the Columbia Basin. Incidence of late-blight-infected shoots from infected seed tubers was significantly greater when foliage was exposed to wet periods in mist chambers (mist for 45 s every 15 min) for either 24 or 48 h than when not exposed to a wet period. Proportion of infected shoots from infected tubers was 0.210 to 0.261 in a moist environment versus 0.013 to 0.052 in a nonmist environment. Development of chlorosis, necrosis, and sporangia occurred on shoots that emerged from infected, symptomatic tubers buried in soil. However, approximately 20% of the infected shoots produced sporangia before stems had visible discoloration of late-blight symptoms. Sporulation was sparse and formed near the soil line on some of the shoots after 24 h in the moist environment. The latent period or time from inoculation to sporulation on young stems of Russet Burbank was 5 to 6 days, which is too long to account for an infection from either sporangia or zoospores at the soil level of shoots during the wet period in this study. Sporangia were infective when placed directly on eyes of whole tubers before planting. Leaflets touching a loamy fine sand infested with sporangia developed typical late-blight lesions beginning at the leaflet tip within 7 days after a 24-h wet period and the infested loamy fine sand was infective when splashed on leaflets.

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Latent Infection of Potato Seed Tubers by Phytophthora infestans During Long-Term Cold Storage

Plant Disease ◽

10.1094/pdis-93-9-0940 ◽

2009 ◽

Vol 93 (9) ◽

pp. 940-946 ◽

Cited By ~ 13

Author(s):

Dennis A. Johnson ◽

Thomas F. Cummings

Keyword(s):

Late Blight ◽

Phytophthora Infestans ◽

Pacific Northwest ◽

Cold Storage ◽

Latent Infection ◽

Seed Tuber ◽

Potato Seed ◽

Seed Tubers ◽

Humidity Chamber

Latent infection of potato seed tubers by Phytophthora infestans was determined following inoculation of tubers and typical seed tuber storage conditions in the Pacific Northwest. Severity of late blight increased over 182 to 209 days during two storage seasons at mean temperatures of 4.1 and 4.2°C. From 0 to 44% of inoculated tubers sampled at given intervals were asymptomatic. However, P. infestans sporangia were observed on slices from these tubers when incubated in a humidity chamber at 15°C or late blight symptoms developed in asymptomatic tubers obtained following storage when incubated at 22 to 23°C for 3 weeks. Development of P. infestans sporangia and symptoms of late blight in asymptomatic seed tubers indicated latent infection of tubers by P. infestans during long-term cold storage. Sporulation was observed after 21 to 24 h on symptomatic tubers and 6 to 20 days on asymptomatic tubers that were removed from storage and incubated in a humidity chamber at 15°C. Latent infection of seed tubers and production of viable sporangia of P. infestans were demonstrated after long-term cold storage of infected potato tubers.

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First Report of Fludioxonil-Resistant Isolates of Fusarium spp. Causing Potato Seed-Piece Decay

Plant Disease ◽

10.1094/pdis-92-1-0172a ◽

2008 ◽

Vol 92 (1) ◽

pp. 172-172 ◽

Cited By ~ 16

Author(s):

R. D. Peters ◽

H. W. Platt ◽

K. A. Drake ◽

R. H. Coffin ◽

S. Moorehead ◽

...

Keyword(s):

Seed Piece ◽

Solanum Tuberosum L ◽

Potato Seed ◽

Fusarium Spp ◽

Benzimidazole Fungicides ◽

First Report ◽

Seed Tubers ◽

Seed Piece Decay ◽

Potato Seed Piece ◽

Petri Dishes

Potato (Solanum tuberosum L.) diseases incited by Fusarium spp. include postharvest dry rot and seed-piece decay. Fusarium seed-piece decay is commonly controlled by preplant applications of chemical seed treatments. However, isolates of Fusarium spp. resistant to benzimidazole fungicides have been reported (2,4). In the spring of 2007, samples of cut seed tubers (cvs. Shepody and Russet Burbank) showing extensive symptoms of decay were received from three seedlots in Prince Edward Island (PE) and one seedlot in Saskatchewan (SK), Canada. All seed tubers had been treated with fludioxonil (Maxim Potato Seed Protectant [PSP], 0.5% fludioxonil) following cutting and then stored for 10 to 14 days prior to planting. Using standard isolation protocols (4), the 19 potato tuber pieces examined from PE and 2 from SK yielded 21 Fusarium isolates for further study. Five isolates (including both isolates from SK) were identified as Fusarium sambucinum Fuckel and the remaining 16 isolates were identified as F. coeruleum (Libert) Sacc. (3). To confirm identifications, isolates were compared with two known standards of each of F. sambucinum and F. coeruleum identified by K. Seifert (Agriculture and Agri-Food Canada, Ottawa, ON) by DNA sequencing of the partial β-tubulin gene or the translation elongation factor 1-α ( http://fusarium.cbio.psu.edu ; [1]). These standard isolates were also used as fludioxonil-sensitive controls in amended agar assays for chemical sensitivity. Agar plugs (5 mm in diameter) taken from the margins of 7-day-old cultures of the Fusarium isolates were transferred to petri dishes containing ½-strength potato dextrose agar amended with 0, 0.1, 1.0, 10.0, or 100.0 mg/liter of fludioxonil. Fludioxonil (Maxim PSP, 0.5% a.i.) was prepared as a stock solution in sterile distilled water and added to the molten agar after autoclaving. Culture incubation and mycelial growth measurements were performed as described previously (4). Measurements from four replicate petri dishes per concentration of fludioxonil were taken. Calculated EC50 values (fludioxonil concentration inhibiting pathogen growth by 50%) were obtained. The trial was repeated three times. The two standard isolates of F. sambucinum were sensitive to fludioxonil, with mean EC50 values of 0.002 (±0.002 standard error [SE]) and 0.005 (±0.002 SE) mg/liter. The two standard isolates of F. coeruleum were also sensitive to fludioxonil, with mean EC50 values of 0.17 (±0.005 SE) and 0.19 (± 0.005 SE) mg/liter. All other tested isolates of F. sambucinum and F. coeruleum were resistant to fludioxonil and showed no growth inhibition even at 100 mg of fludioxonil per liter. To our knowledge, this is the first report of resistance to fludioxonil in isolates of Fusarium spp. causing potato seed-piece decay. Since the isolates of F. sambucinum were also resistant to thiophanate-methyl and thiabendazole (data not shown), multiclass (benzimidazole and pyrrole) resistance was also documented. References: (1) D. M. Geiser et al. Eur. J. Plant Pathol. 110:473, 2004. (2) L. M. Kawchuk et al. Am. Potato J. 71:185, 1994. (3) P. E. Nelson et al. Fusarium Species: An Illustrated Manual for Identification. Pennsylvania State University Press, 1983. (4) R. D. Peters et al. Plant Dis. 85:1030, 2001.

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Potato Seed Piece Calcium can Influence Tuber Yield

HortScience ◽

10.21273/hortsci.31.4.592d ◽

1996 ◽

Vol 31 (4) ◽

pp. 592d-592

Author(s):

Christopher C. Gunter ◽

Matthew D. Kleinhenz ◽

Jiwan P. Palta

Keyword(s):

Seed Piece ◽

Pathogenic Bacteria ◽

Tuber Yield ◽

Seed Tuber ◽

Calcium Nitrate ◽

Soft Rot ◽

Economic Loss ◽

Potato Seed ◽

Seed Tubers ◽

Supplemental Calcium

Pathogenic bacteria (Erwinia spp.) can have a significant impact on stand establishment and sprout health. These bacteria cause soft rot of the seed piece, which is common in wet spring conditions resulting in great economic loss. Recent studies have demonstrated that the incidence and severity of soft rot can be significantly reduced by increasing tuber calcium. We investigated the influence of seed piece calcium on tuber production. Field growing potato plants were treated with supplemental calcium during tuber bulking (calcium at 168 kg·ha–1 from calcium nitrate or N-Hib) to increase the seed tuber medullary calcium levels. All three cultivars (`Superior', `Atlantic', `Dark Red Norland') responded to supplemental calcium application with increases in mean calcium contents, even though soil tests showed high native calcium levels (1000 kg·ha–1). Seed tubers were sampled for calcium by removing a longitudinal slice from the center of each tuber and planting one of the resulting halves for seed piece decay evaluation and the other for yield evaluation. Calcium nitrate-treated seed tubers produced higher yields compared to ammonium nitrate and N-Hib in `Atlantic' in `Dark Red Norland'. This trend did not hold true for `Superior'. Our results suggest that a) it is possible to increase seed piece tuber calcium levels with supplemental calcium application even in soils testing high in calcium and b) improving the calcium concentration of the seed piece can increase tuber yield in some cultivars.

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Age of potato seed-tubers influences protein synthesis during sprouting

Physiologia Plantarum ◽

10.1034/j.1399-3054.1993.890203.x ◽

1993 ◽

Vol 89 (2) ◽

pp. 262-270 ◽

Cited By ~ 1

Author(s):

G. N. Mohan Kumar ◽

N. Richard Knowles

Keyword(s):

Protein Synthesis ◽

Potato Seed ◽

Seed Tubers

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Determination of optimum tuber planting density in the potato varieties Pentland Squire, Cara, Estima, Maris Piper and King Edward

The Journal of Agricultural Science ◽

10.1017/s0021859600071525 ◽

1992 ◽

Vol 119 (1) ◽

pp. 35-44 ◽

Cited By ~ 7

Author(s):

D. C. E. Wurr ◽

J. R. Fellows ◽

E. J. Allen

Keyword(s):

Complex Analysis ◽

Seed Tuber ◽

Tuber Size ◽

Planting Density ◽

Potato Seed ◽

Stem Density ◽

Seed Tubers ◽

Net Returns ◽

Analysis Technique ◽

The Cost

SummaryThirty-two experiments examining the effects of the weight and within-row spacing of potato seed tubers on graded tuber yields of five varieties were conducted on eight sites from 1980 to 1985. A complex analysis technique was used to combine these data and estimate the optimum tuber planting densities for different ratios of seed cost to small (40–60 mm) and large (60–80 mm) ware value. The same technique could be applied to any other combination of seed cost, ware size and ware value.The optimum tuber planting density decreased with increasing seed-tuber weight. Differences in optimum planting density between varieties were much greater with small (35 g) than with large (105 g) seed tubers and decreased as the cost of seed increased relative to the value of ware. As large ware became worth more than small ware the influence of increasing seed cost on the optimum density was reduced. As the value of large ware increased, net returns increased and the effect of seed cost on net returns was reduced. Mean tuber size decreased with increasing stem density at harvest and at the same stem density was lower in varieties producing more daughter tubers/stem. Changes of mean tuber size (μ) and the spread of yield across size grades (σ) with time were well described by parallel curves in different varieties. It is suggested that in future it may not be necessary to determine optimum tuber planting densities by complex experiments involving several seed-tuber weights and spacings. Instead μ and σ could be estimated from simple experiments and tuber spacings determined by comparison with control varieties.

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Effect of potato spindle tuber viroid on sexual reproduction and viroid transmission in true potato seed

Canadian Journal of Botany ◽

10.1139/b86-048 ◽

1986 ◽

Vol 64 (2) ◽

pp. 336-340 ◽

Cited By ~ 23

Author(s):

M. E. Grasmick ◽

S. A. Slack

Keyword(s):

Fruit Development ◽

Seed Weight ◽

Seed Set ◽

Transmission Rate ◽

Pollen Viability ◽

Polyacrylamide Gel Electrophoresis ◽

Potato Spindle Tuber Viroid ◽

Potato Seed ◽

True Potato Seed ◽

Viroid Infection

The effect of potato spindle tuber viroid infection on pollen viability, fruit-set, botanical seed set, seed weight, and seed germination in potatoes was determined. Pollen collected from the infected cultivar 'Monona' was less viable than pollen collected from healthy plants. Pollen collected from infected plants reduced seed set significantly but did not reduce fruit development or seed set in all cultivars tested. For some cultivars, infected maternal plants increased the frequency of fruit development and seed weight compared with healthy controls. True potato seed from viroid-infected 'Katahdin' × 'Superior' crosses germinated at a higher rate than did seed from comparable uninfected parents. Progeny from viroid-infected parents that exhibited potato spindle tuber viroidlike symptoms did not always test positive for potato spindle tuber viroid by bioassay or polyacrylamide gel electrophoresis tests. Efficiency of potato spindle tuber viroid detection by bioassay was highest for seedlings 2 weeks after imbibition. Potato spindle tuber viroid was detected in 100% of the progeny tested after true potato seed was stored at 4 °C for 12 years. Tests on selfed true potato seed from the viroid-infected cultivar 'Monona' demonstrated a transmission rate of 100% after subinoculation of initial bioassay plants.

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Recognition of Tomato Late Blight by using DWT and Component Analysis

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v7i1.pp194-199 ◽

2017 ◽

Vol 7 (1) ◽

pp. 194

Author(s):

Hiteshwari Sabrol ◽

Satish Kumar

Keyword(s):

Principal Component Analysis ◽

Late Blight ◽

Distance Measure ◽

Recognition Accuracy ◽

Principal Component ◽

Component Analysis ◽

Plant Diseases ◽

Kernel Principal Component Analysis ◽

Healthy Plant ◽

Testing Dataset

Plant disease recognition concept is one of the successful and important applications of image processing and able to provide accurate and useful information to timely prediction and control of plant diseases. In the study, the wavelet based features computed from RGB images of late blight infected images and healthy images. The extracted features submitted to Principal Component Analysis (PCA), Kernel Principal Component Analysis (KPCA) and Independent Component Analysis performed (ICA) for reducing dimensions in feature data processing and classification. To recognize and classify late blight from healthy plant images are classified into two classes i.e. late blight infected or healthy. The Euclidean Distance measure is used to compute the distance by these two classes of training and testing dataset for tomato late blight recognition and classification. Finally, the three-component analysis is compared for late blight recognition accuracy. The Kernel Principal Component Analysis (KPCA) yielded overall recognition accuracy with 96.4%.

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Improving Evaluation of Potato Resistance to Rhizoctonia solani infection by Optimizing Inoculum Method Combined with Toxin-based Assay

10.21203/rs.2.23572/v1 ◽

2020 ◽

Author(s):

Xiaoyu Zhang ◽

Xing Xing ◽

Yayan Feng ◽

Zhuo Yu ◽

Jianjun Hao ◽

...

Keyword(s):

Rhizoctonia Solani ◽

Seed Piece ◽

Wheat Bran ◽

Agar Medium ◽

Stem Canker ◽

Field Trials ◽

Potato Seed ◽

Potato Resistance ◽

Highly Correlated ◽

Potato Seedlings

Abstract Background: Rhizoctonia solani causes stem canker and significantly impacts the production of potato. Conventional assay to evaluate potato resistance using R. solani inoculum is time consuming. To establish an effective and fast assay, 20 potato germplasms were examined using both R. solani inoculum and R. solani-derived toxin (RS toxin). Results: In field trials of 2009 and 2010, wheat-bran-based inoculum of R. solani was incorporated at either 0, 2, 3, 4 or 5 g per seed piece in the soil followed by sowing potato seed pieces in the furrow. Stem canker was evaluated in the growing season. Inoculum of wheat-bran-based 2, 3, or 4 g could well distinguish resistance of potato germplasms. For a quick assay of resistance screening, a toxin-based method was established by treating potato seedlings with the toxin of R. solani (RS toxin). RS toxin was prepared by heating R. solani culture. Potato seedlings were obtained through tissue culture and grown in Murashige and Skoog medium. Seedlings at the stage of 12 cm in height were transferred into agar medium amended with RS toxin and incubated for eight days. The inhibition caused by RS toxin was positively correlated with toxin concentration. By evaluating various potato cultivars that have different sensitivities to toxin, the inhibition of potato stems sections and seedlings was from 33% to 100% and from 32% to 148%, respectively. Results of toxin-based evaluation were highly correlated with the field data using pathogen inoculum (r = 0.731, P < 0.01). Conclusions: Inoculation with wheat bran-mediated R. solani of 2, 3 or 4 g per seed piece was an effective method for the evaluation of potato resistance in field trials. The toxin-based assay could improve efficiency and speed of disease resistance evaluation of potato germplasms. Both assays showed that none of the 20 potato materials was completely resistant to R. solani. However, cultivar ‘Desiree’ had the lowest level of disease, whereas ‘Atlantic’, ‘Favorita’, and ‘Shepody’ showed the high susceptibility.

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