1001 ANOXIA TOLERANCE OF MAIZE SEEDLING ROOTS

We have been examining the response of maize seedling roots to oxygen stress. Previously, we have shown that maize seedlings with primary root lengths of 10cm or greater require a pretreatment with low oxygen (hypoxia) for survival of greater than 12 hours of anoxia. During the pretreatment there is induction of mRNA and increase in enzymatic activity of alcohol dehydrogenase (ADH) and other enzymes that are necessary for alcoholic fermentation. However, we have found that younger seedlings do not need a pretreatment to survive anoxia. They appear to have high levels of ADH and other enzymes that are needed for anaerobic survival at levels equivalent to those that are induced in older seedlings. These results suggest that, at the time of seedling emergence, seedlings may be more adapted to oxygen stress than during later stages of growth.

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The colonization of maize seedling roots and rhizosphere by Fusarium spp. in Mississippi in two soil types under conventional tillage and notillage systems

Phytoprotection ◽

10.7202/706203ar ◽

2005 ◽

Vol 81 (3) ◽

pp. 97-106 ◽

Cited By ~ 8

Author(s):

P. Soonthornpoct ◽

L.E. Trevathan ◽

D. Ingram

Keyword(s):

Dry Weight ◽

Conventional Tillage ◽

Maize Seedling ◽

Soil Types ◽

Silty Clay ◽

Maize Seedlings ◽

Planting Dates ◽

Primary Roots ◽

Seedling Roots ◽

Hybrid Maize

Pioneer 3167 hybrid maize was planted on two soil types in Mississippi on four dates annually from 1995 to 1997 and was sampled at weekly intervals beginning one week and ending 4 weeks after planting. Plots were either tilled with a do-all and rows formed in the fall or were left undisturbed until planting in the spring. Under tillage, Fusarium spp. were isolated most frequently at the earliest and latest planting dates when seedlings were sampled at 10 and 17 days. In no-tillage plots, the overall isolation frequency was lower than in conventional-tillage plots and decreased with later planting dates and sampling times. The highest Fusarium populations were found in the rhizosphere of a silt loam in conventional-tillage plots when seedlings were sampled 28 days after the second planting in 1997, compared to populations from a silty clay soil. Fusarium moniliforme, F. solani and F. oxysporum were the predominant Fusarium spp. isolated from maize seedling roots. In pathogenicity tests, F. moniliforme and F. solani produced measurable effects on maize seedlings. F. moniliforme reduced the length of primary roots and decreased the number of secondary roots, and F. solani reduced root dry weight of maize seedlings.

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Dynamic changes of antioxidants and fermentative metabolites in apple peel in relation to storage, controlled atmosphere, and initial low oxygen stress

Scientia Horticulturae ◽

10.1016/j.scienta.2021.110312 ◽

2021 ◽

Vol 288 ◽

pp. 110312

Author(s):

Marina Buccheri ◽

Valentina Picchi ◽

Maurizio Grassi ◽

Davide Gandin ◽

Giulia Bianchi ◽

...

Keyword(s):

Controlled Atmosphere ◽

Low Oxygen ◽

Dynamic Changes ◽

Oxygen Stress ◽

Apple Peel

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Suppression of Cellulase and Polygalacturonase and Induction of Alcohol Dehydrogenase Isoenzymes in Avocado Fruit Mesocarp Subjected to Low Oxygen Stress

PLANT PHYSIOLOGY ◽

10.1104/pp.96.1.269 ◽

1991 ◽

Vol 96 (1) ◽

pp. 269-274 ◽

Cited By ~ 45

Author(s):

Angelos K. Kanellis ◽

Theophanes Solomos ◽

Kalliopi A. Roubelakis-Angelakis

Keyword(s):

Alcohol Dehydrogenase ◽

Low Oxygen ◽

Alcohol Dehydrogenase Isoenzymes ◽

Oxygen Stress ◽

Avocado Fruit

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Morphophysiological dormancy and germination ecology in diaspores of the subtropical palm Phoenix canariensis Chabaud

Botany ◽

10.1139/cjb-2021-0126 ◽

2021 ◽

Author(s):

Lanlan He ◽

Ganesh K. Jaganathan ◽

Baolin Liu

Keyword(s):

Seed Dormancy ◽

Seedling Emergence ◽

Primary Root ◽

Germination Percentage ◽

Early Summer ◽

Germination Ecology ◽

Phoenix Canariensis ◽

Morphophysiological Dormancy ◽

Cotyledonary Petiole ◽

Seed Dormancy And Germination

The timing of germination is a crucial event in a plant’s life cycle. Seed dormancy and germination mechanisms are important factors regulating seedling emergence. Since detailed experimental evidence for germination pattern of Phoenix canariensis colonizing sub-tropical climate is scarce, we investigated seed dormancy and germination ecology of P. canariensis. We found that the embryo is underdeveloped at the time of dispersal and doubles in size before the cotyledonary petiole (CP) protrudes through the operculum. The primary root and plumule emerge from the elongated CP outside the seed. In light/dark at 30/25°C, the CP emerged from 8% of the diaspores within 30 days and from 76% within 14 weeks. Thus, 8% of the diaspores have MD and the others MPD. Removal of the pericarp and operculum resulted in 100% germination within 5 days in light/dark at 30/25°C. Cold and warm stratification as well as treatment with GA3 significantly increased the germination speed, but the final germination percentage was not significantly increased. Seed germination was synchronized in early summer when seed dormancy was released by cold stratification in the soil over winter. A remote-tubular germination type and intricate root system provide an ecological advantage to the seedling establishment.

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Response of pomegranate arils (cv. Wonderful) to low oxygen stress under active modified atmosphere condition

Journal of the Science of Food and Agriculture ◽

10.1002/jsfa.9276 ◽

2018 ◽

Vol 99 (3) ◽

pp. 1088-1097 ◽

Cited By ~ 1

Author(s):

Zinash A Belay ◽

Oluwafemi J Caleb ◽

Pramod V Mahajan ◽

Umezuruike L Opara

Keyword(s):

Modified Atmosphere ◽

Low Oxygen ◽

Oxygen Stress ◽

Pomegranate Arils

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Differential response of Daphnia genotypes to oxygen stress: respiration rates, hemoglobin content and low-oxygen tolerance

Oecologia ◽

10.1007/bf00379661 ◽

1985 ◽

Vol 65 (4) ◽

pp. 487-491 ◽

Cited By ~ 87

Author(s):

Lawrence J. Weider ◽

Winfried Lampert

Keyword(s):

Differential Response ◽

Low Oxygen ◽

Hemoglobin Content ◽

Oxygen Stress ◽

Oxygen Tolerance ◽

Respiration Rates

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Low-Oxygen Stress in Plants

10.1007/978-3-7091-1254-0 ◽

2014 ◽

Cited By ~ 7

Keyword(s):

Low Oxygen ◽

Oxygen Stress

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Pyrophosphate as an alternative energy currency in plants

Biochemical Journal ◽

10.1042/bcj20200940 ◽

2021 ◽

Vol 478 (8) ◽

pp. 1515-1524

Author(s):

Abir U. Igamberdiev ◽

Leszek A. Kleczkowski

Keyword(s):

Metabolic Pathways ◽

Energy Efficient ◽

Alternative Energy ◽

Plant Cells ◽

Atp Synthesis ◽

Continuous Operation ◽

Low Oxygen ◽

Pyruvate Phosphate Dikinase ◽

Oxygen Stress ◽

Membrane Bound

In the conditions of [Mg2+] elevation that occur, in particular, under low oxygen stress and are the consequence of the decrease in [ATP] and increase in [ADP] and [AMP], pyrophosphate (PPi) can function as an alternative energy currency in plant cells. In addition to its production by various metabolic pathways, PPi can be synthesized in the combined reactions of pyruvate, phosphate dikinase (PPDK) and pyruvate kinase (PK) by so-called PK/PPDK substrate cycle, and in the reverse reaction of membrane-bound H+-pyrophosphatase, which uses the energy of electrochemical gradients generated on tonoplast and plasma membrane. The PPi can then be consumed in its active forms of MgPPi and Mg2PPi by PPi-utilizing enzymes, which require an elevated [Mg2+]. This ensures a continuous operation of glycolysis in the conditions of suppressed ATP synthesis, keeping metabolism energy efficient and less dependent on ATP.

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