Age of potato seed-tubers influences protein synthesis during sprouting

The physiological mechanisms leading to a decline in sprout-vigor, root growth potential and apical dominance during long-term aging of potato seed tubers are currently under investigation. Malondialdehyde (MDA) and ethane, products of peroxidative degradation of PUFA increase in seed-tuber tissues with advancing age (from 2 to 32 months of storage). MDA is known to react with free amino acids to produce lipofuscin-like fluorescent compounds (FC), which build-up in aging/senescent tissues of plants and animals. With advancing seed-tuber age, an increase in free amino acids, MDA and FC concentrations was evident. Moreover, high levels of MDA have been shown to reduce protein synthesis in both plant and animal cells. We therefore examined the extent to which seed-tuber age affects protein synthesizing capacity of tuber tissues during sprouting. Tissue disks from 6- and 18-mo-old seed-tubers at various stages of sprouting, were compared for their protein synthesizing ability by monitoring the incorporation of radiolabelled amino acids into TCA precipitable products. The rate of incorporation (dpm mg protein-1 min-1) was 1.8 to 5.4-fold higher in tissue from 6-mo-old, as compared to that from 18-mo-old seed tubers, at similar stages of sprout development. Loss in protein synthesizing ability (possibly due to direct peroxidative damage) may be an important factor contributing to loss of sprout-vigor from aged potato 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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Effects of Gibberellic Acid (GA3) on Sprouting and Quality of Potato Seed Tubers in Diffused Light and Pit Storage Conditions

Journal of Biological Sciences ◽

10.3923/jbs.2006.723.733 ◽

2006 ◽

Vol 6 (4) ◽

pp. 723-733 ◽

Cited By ~ 3

Author(s):

Solomon I. Shibairo . ◽

Paul Demo . ◽

Jackson N. Kabira . ◽

Peter Gildemacher . ◽

Esther Gachango . ◽

...

Keyword(s):

Gibberellic Acid ◽

Storage Conditions ◽

Potato Seed ◽

Seed Tubers ◽

Diffused Light

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Seed Borne Late Blight of Potato

Plant Health Progress ◽

10.1094/php-2002-0129-01-hm ◽

2002 ◽

Vol 3 (1) ◽

pp. 14 ◽

Cited By ~ 5

Author(s):

Mary L. Powelson ◽

Robin Ludy ◽

Heather Heather ◽

Debra A. Inglis ◽

Babette Gundersen ◽

...

Keyword(s):

Late Blight ◽

Seed Piece ◽

Transmission Rate ◽

Seed Transmission ◽

Management Program ◽

Healthy Plant ◽

Potato Seed ◽

Stand Establishment ◽

Seed Tubers ◽

Healthy Seed

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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