Imbibition Rates in Film-coated Shrunken-2 Sweet Corn (Zea mays) Seeds

Mutant endosperm associated with shrunken-2 sweet corn possesses a high osmotic potential that increases the rate of imbibition. Membrane damage associated with the rapid influx of water during imbibition can play a role in the poor emergence and seedling vigor associated with sweet corn germination. Film-coating as a seed treatment has been used to improve germination and vigor in sweet corn. This improvement may be associated with alterations in the kinetics of imbibition. Two seed lots of shrunken-2 sweet corn, low-vigor `Even Sweeter' and high vigor `Sugar Bowl', were treated with a polymer film-coating and evaluated for differences in water uptake. Imbibition curves were established for nontreated and film-coated seeds. Seeds were weighed every hour for 6 hours and showed a significant difference between the two treatments in fresh weight for both cultivars. This pattern continues throughout the imbibition phase of germination and continues into the lag period. Bulk conductivity tests resulted in no significant mean difference between untreated and film treated seeds after 24 hours. Film treatment assumes characteristics of a hydrophilic polymer. Electrolyte leakage is not reduced and imbibition rate increases by 18% for both varieties of film-coated seeds.

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422 Water Uptake Patterns in shrunken-2 Sweet Corn (Zea mays) during Imbibition of Film-coated Seeds

HortScience ◽

10.21273/hortsci.35.3.466a ◽

2000 ◽

Vol 35 (3) ◽

pp. 466A-466

Author(s):

Tina Wilson ◽

Robert Geneve ◽

Brent Rowell

Keyword(s):

Water Uptake ◽

Seed Treatment ◽

Sweet Corn ◽

Membrane Damage ◽

Film Coating ◽

Fresh Weight ◽

Fluorescent Compound ◽

Hydrophobic Polymer ◽

Trisodium Salt ◽

Water Uptake Patterns

Membrane damage associated with rapid influx of water during imbibition can play a role in the poor emergence and seedling vigor associated with sweet corn germination. Film-coating as a seed treatment has been used to improve germination and vigor in sweet corn and this improvement may not be associated with changes in imbibition rate. Two seed lots of shrunken-2 variety sweet corn, low-vigor `Even Sweeter' and high-vigor `Sugar Bowl', were treated with a hydrophilic polymer film-coating and evaluated for differences in emergence and water uptake. Both cultivars were grown at 19, 21, and 26 °C with no effect on emergence due to film-coating. Imbibition curves were established for untreated and hydrophilic film-coated seeds. Film-coated seeds showed an 18% increase in fresh weight compared to untreated seeds for both cultivars during a 6-h period. Bulk conductivity tests resulted in no significant mean difference between untreated and hydrophilic-treated seeds after 24 h. These seed lots have been treated with a hydrophobic polymer and are currently being evaluated for cold temperature emergence and imbibition rates. Water entry during imbibition will also be compared for untreated sugary (su) and shrunken-2 (sh2) seeds using the fluorescent compound trisodium salt, 8-hydroxypyrene-1, 3,6-trisulfonic acid (HPTS).

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Enhanced Emergence and Seedling Vigor in shrunken-2 Sweet Corn via Seed Disinfection and Solid Matrix Priming

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.117.3.400 ◽

1992 ◽

Vol 117 (3) ◽

pp. 400-403 ◽

Cited By ~ 14

Author(s):

Carlos A. Parera ◽

Daniel J. Cantliffe

Keyword(s):

Seed Treatment ◽

Sweet Corn ◽

Germination Rate ◽

Dry Weight ◽

Cold Test ◽

Field Trials ◽

Solid Matrix ◽

Significant Difference ◽

Seed Disinfection ◽

Emergence Percentage

Presowing seed treatments were devised to improve emergence and crop uniformity of two sweet corn (Zea mays L.) cultivars [`Crisp N' Sweet 711' (CNS-711) and `How Sweet It Is' (HSII)] that carry shrunken-2 (sh2) mutant endosperm. The treatments included a fungicide combination, sodium hypochlorite (SH), solid matrix priming (SMP), and SMP combined with SH during treatment (SMPSH). Seed germination was tested in a laboratory cold test. Emergence percentage, emergence rate index (ERI), and seedling dry weight were calculated from field trials. CNS-711, in the cold test and field trials, had a higher germination rate, ERI, final emergence, and seedling dry weight than HSII. In both cultivars, SMPSH significantly improved germination in the cold test and final emergence and ERI in the field trials for HSII compared to nontreated seeds. There was no significant difference between the fungicide and SMPSH treatments regardless of cultivar. These results suggest that the combination of SMP and disinfection with SH can be an alternative seed treatment to fungicides to improve uniformity and stand establishment in sh2 sweet corns.

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Seed Maturity Influences Germination and Vigor of Two Shrunken-2 Sweet Corn Hybrids

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.116.3.401 ◽

1991 ◽

Vol 116 (3) ◽

pp. 401-404 ◽

Cited By ~ 9

Author(s):

Alicia M. Borowski ◽

Vincent A. Fritz ◽

Luther Waters

Keyword(s):

Seed Weight ◽

Sweet Corn ◽

Cold Test ◽

Seed Vigor ◽

Seedling Vigor ◽

Fresh Weight ◽

Germination Test ◽

Corn Hybrids ◽

Seed Maturity ◽

Seed Harvest

The objective of this study was to examine seed maturity at harvest as it relates to seed vigor in two commercial shrunken-2 (sh2 J sweet corn hybrids (Zea mays L. var rugosa Bonaf., cvs. Florida Staysweet, Crisp N' `Sweet 710). Seed harvest began at 0.76 g H2O/g fresh weight in 1987 and at 0.70 g H2O/g fresh weight in 1988 and 1989, and was continued at gradually declining moisture levels until frost. In five different tests of seed performance, seed of `Florida Staysweet' (FLASS) harvested between 0.23 to 0.57 g H2O/g fresh weight in 1987 possessed the highest seedling vigor. In 1988 and 1989, maximum vigor was achieved by FLASS seed harvested from 0.40 to 0.60 g H2O/g fresh weight and `Crisp N' Sweet 710' (CNS) seed harvested from 0.45 to 0.65 g H2O/g fresh weight. Standard germination test, seedling growth cold test (SGCT), and seed leachate conductivity provided the most consistent results to `determine optimum seed maturity. Seed weight was not as reliable an indicator of seed vigor in 1988 and 1989 as it was in 1987, and endosperm and embryo weights did not correlate with seedling vigor in any year.

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210 Water Uptake in Film-coated shrunken-2 Sweet Corn (Zea mays)

HortScience ◽

10.21273/hortsci.34.3.478c ◽

1999 ◽

Vol 34 (3) ◽

pp. 478C-478

Author(s):

Tina Wilson ◽

Robert Geneve ◽

Brent Rowell

Keyword(s):

Electrical Conductivity ◽

Water Uptake ◽

Electrolyte Leakage ◽

Seed Treatment ◽

Sweet Corn ◽

Film Coating ◽

Soil Conditions ◽

Bulk Electrical Conductivity ◽

Additional Conductivity ◽

Water Uptake Patterns

One possible influence film-coating may have on seeds is modifying water uptake and electrolyte leaking during imibibition. Film-coating is a seed treatment that can improve sweet corn germination, especially under cold soil conditions. Two shrunken-2 sweet corn varieties (`Even Sweeter' and `Sugar Bowl') were treated with a polymer film-coating and evaluated for water uptake patterns during imibibition. `Even Sweeter' is a low-vigor sweet corn, while `Sugar Bowl' is a high-vigor variety. Standard germination tests were performed according to AOSA rules and suggest film-coated seeds germinated at a slower rate than untreated seeds. After 4 days of imibibition, `Sugar Bowl' film-coated seeds had 5% germination, while untreated seeds had ≈20% germination. However, after 7 days, film-coated seeds had 94% germination with untreated seeds at 80% germination. Results were similar for `Even Sweeter'. Bulk electrical conductivity readings were taken over 24 h to determine the amount of electrolyte leakage during imibibition. Low-vigor `Even Sweeter' had 92% higher overall leakage than high-vigor `Sugar Bowl'. Additional conductivity readings were taken for both seed lots every 2 h for 12 h. Film-treated seeds leaked 15% less than untreated seeds for `Sugar Bowl'. However, `Even Sweeter' film-coated seeds actually leaked 17% more than the untreated seeds. In both cases, 70% of electrolyte leakage occurred within the first 12 h of imibibition. An imibibition curve was established for the two seed lots comparing untreated and film-coated seeds. During the first 6 h of water uptake, film-treated seeds weighed ≈50% more than the untreated seeds for both `Even Sweeter' and `Sugar Bowl'. Pathways for water uptake as influenced by film-coating shrunken-2 seeds will also be presented.

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INFLUENCE OF DRY-BACK TEMPERATURES AFTER SOLID MATRIX PRIMING ON SUBSEQUENT SEED PERFORMANCE

HortScience ◽

10.21273/hortsci.27.6.576e ◽

1992 ◽

Vol 27 (6) ◽

pp. 576e-576

Author(s):

Carlos A. Parera ◽

Daniel J. Cantliffe

Keyword(s):

Enzyme Activity ◽

Moisture Content ◽

Seed Treatment ◽

Sweet Corn ◽

Solid Matrix ◽

Acid Decarboxylase ◽

Decarboxylase Activity ◽

Fresh Weight ◽

Seed Respiration ◽

Low Rate

The effects of the dry-back temperature on sh2 sweet corn seeds primed via solid matrix priming combined with sodium hypochlorite (SMPsh) were studied. Seeds of two sh2 sweet corn cultivars: Crisp N'Sweet 711 (CNS-711) and How Sweet It Is (HSII) were primed via SMPsh. After the treatment, the seeds were dried-back from 50-54% to 6-7% moisture content at 20, 30 or 40C and 25% RH. The rate of dehydration was significantly lower in CNS-711 compared to HSII at all dry-back temperatures. In both cultivars, seed respiration after 4, 16, and 32h of imbibition was greater in those dried at 30 and 40C compared to 20C or non-primed seed. Enzyme activity (glutamic acid decarboxylase activity) was decreased in HSII seeds dried at 20C. There were no differences among treatments in CNS-711. Leakage conductivity was significantly less when the seeds were dried-back at 30C or 40C compared to 20C or nonprimed seeds. Laboratory germination and seedling fresh weight were greater in seeds dried-back at 30C compared the others temperatures or non-primed seeds. The low rate of desiccation at 20C (30h and 8h in CNS-711 and HSII, respectively) may not suppress germination events after priming, thus damaging the embryo during dry-back. This work demonstrated the importance of dry-back temperature to the efficacy of SMPsh seed treatment in sh2 corn.

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Solid Effluent from Thermophilic Anaerobic Digestion of Poultry Litter as a Potential Fertilizer

HortScience ◽

10.21273/hortsci.39.4.877b ◽

2004 ◽

Vol 39 (4) ◽

pp. 877B-877

Author(s):

Barbara E. Liedl* ◽

John Bombardiere ◽

Melissa L. Williams ◽

Amanda Stowers ◽

Christopher Postalwait ◽

...

Keyword(s):

Nutrient Management ◽

Sweet Corn ◽

Statistical Significance ◽

Tomato Fruit ◽

Poultry Litter ◽

Management Program ◽

Fresh Weight ◽

Perennial Crop ◽

Intensive Farming ◽

Significant Difference

Fertilizer costs and increased awareness of non-point source pollution run-off amplify the pressures on farm economics. Intensive farming operations provided the impetus for our study using effluent from anaerobic thermophilically digested poultry litter as a potential fertilizer. Five fertilizer treatments were used: unfertilized control, pelletized municipal sludge, commercial crop specific products, 1x digested solids and 2x digested solids. All four applications of fertilizer were equalized for nitrogen based on commercial product recommendations. Beds treated with 2x solids accumulated higher percentage of organic matter over the 5-year period. A statistically significant increase in phosphorus was found in the solids beds in 2003. Beds with 2x solids showed statistical significance for Mg, Zn and Cu. Fertilizer trials included blueberries, tomatoes, potatoes, and sweet corn. Potato fresh weight was not significantly different in 2002 or 2003, but was in 2001. Tomato fruit number was not significantly different in 2001 or 2003, but was in 2002. Tomato fresh weight for 2x solids was not significantly different from the commercial or pelletized sludge treatments in 2002 and 2003 suggesting that tomato may discriminate between treatments. Commercial and pelletized sludge fertilizers were statistically better for sweet corn fresh ear weight and number of ears in 2002 and 2003. Blueberry yields were not significantly different between treatments for any year. As this is a perennial crop, it may be several years before a significant difference is observed. While not a total solution, our research shows the effectiveness of digested poultry litter as part of a nutrient management program; making livestock residuals a nutrient resource which offers the potential for organic use.

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Presowing Seed Treatments to Enhance Supersweet Sweet Corn Seed and Seedling Quality

HortScience ◽

10.21273/hortsci.29.4.277 ◽

1994 ◽

Vol 29 (4) ◽

pp. 277-278 ◽

Cited By ~ 7

Author(s):

Carlos A. Parera ◽

Daniel J. Cantliffe

Keyword(s):

Seed Treatment ◽

Sweet Corn ◽

Seedling Emergence ◽

Solid Matrix ◽

Seedling Vigor ◽

Seed Treatments ◽

Tetramethylthiuram Disulfide ◽

Corn Seed ◽

Presowing Treatment ◽

Emergence Percentage

Poor emergence and low seedling vigor are characteristics of many supersweet sweet corn (Zea mays L.) cultivars carrying the shrunken-2 (sh2) gene. Four sh2 sweet corn cultivar seeds [`How Sweet It Is' (HSII), `Crisp N' Sweet 711' (CNS-711), `Sweet Belle' (SB), and `Dazzle' (DZ)] were solid-matrix-primed (SMP), SMP with sodium hypochlorite (SMPcl), treated with a fungicide combination (F) (Imazalil + Captan + Apron + Thiram), or primed with the aforementioned fungicides (SMPf). The seed treatments were tested in the laboratory and the field. Seed imbibition and leachate electrical conductivity were lower in SMP seeds than in nonprimed seeds. In the field, emergence percentage and rate of CNS-711 and SB (high-vigor seeds) were not improved by the seed treatments compared to the nontreated seeds. Emergence percentage and rate of HSII and DZ (considered low-vigor seeds) were improved as a result of SMPcl, SMPf, or F treatments compared to nonprimed seeds. Compared to the F treatment, the SMPcl presowing treatment increased DZ seedling emergence rate and percentage. The combined SMP and seed disinfection via NaOCl seems to be a promising fungicide seed-treatment substitute that improves the stand establishment and seedling vigor of sh2 sweet corn cultivars. Chemical names used: 1-[2-(2,4-dichlorophenyl)-2-(2-propenyloxy)ethyl]-1 H imidazole (Imazalil); N-[(trichloromethyl)thio]-4-cyclohexene-1,2-dicarboximide(Captan); N- (2,6-dimethylphenyl)- N -(methoxyacetyl)alanine methyl ester (Apron); tetramethylthiuram disulfide (Thiram).

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Functional Fractionation of Platelets: Aggregation Kinetics and Glycoprotein Labeling of Differing Platelet Populations

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657259 ◽

1982 ◽

Vol 48 (02) ◽

pp. 211-216 ◽

Cited By ~ 12

Author(s):

V M Haver ◽

A R L Gear

Keyword(s):

Galactose Oxidase ◽

Aggregation Kinetics ◽

Maximal Rate ◽

Membrane Glycoproteins ◽

Whole Cells ◽

Reversible Aggregation ◽

Significant Difference ◽

Small Doses ◽

Major Loss ◽

Kinetics Of

SummaryPlatelet heterogeneity has been studied with a technique called functional fractionation which employs gentle centrifugation to yield subpopulations (“reactive” and “less-reactive” platelets) after exposure to small doses of aggregating agent. Aggregation kinetics of the different platelet populations were investigated by quenched-flow aggregometry. The large, “reactive” platelets were more sensitive to ADP (Ka = 1.74 μM) than the smaller “less-reactive” platelets (Ka = 4.08 μM). However, their maximal rate of aggregation (Vmax, % of platelets aggregating per sec) of 23.3 was significantly lower than the “less-reactive” platelets (Vmax = 34.7). The “reactive” platelets had a 2.2 fold higher level of cyclic AMP.Platelet glycoproteins were labeled using the neuraminidase-galactose oxidase – [H3]-NaBH4 technique. When platelets were labeled after reversible aggregation, the “reactive” platelets showed a two-fold decrease in labeling efficiency (versus control platelets). However, examination of whole cells or membrane preparations from reversibly aggregated platelets revealed no significant difference in Coomassie or PAS (Schiff) staining.These results suggest that the large, “reactive” platelets are more sensitive to ADP but are not hyperaggregable in a kinetic sense. Reversible aggregation may cause a re-orientation of membrane glycoproteins that is apparently not characterized by a major loss of glycoprotein material.

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COMPARISON OF ASCORBIC ACID CONTENT IN IMPORTED TOMATOES AND IN CULTIVARS GROWN IN NOVA SCOTIA

Canadian Journal of Plant Science ◽

10.4141/cjps87-047 ◽

1987 ◽

Vol 67 (1) ◽

pp. 331-335

Author(s):

HAK-YOON JU ◽

W. JOHN MULLIN

Keyword(s):

Ascorbic Acid ◽

Nova Scotia ◽

Vitamin C ◽

Acid Content ◽

Ascorbic Acid Content ◽

Fresh Weight ◽

Atlantic Region ◽

Significant Difference ◽

Cluster Location ◽

Greenhouse Tomatoes

The ascorbic acid (vitamin C) content of fresh imported field tomatoes and Nova Scotia greenhouse and field tomatoes was determined on a bi-weekly basis during the period of availability of each type of tomato to the Nova Scotia consumer in 1984. The average ascorbic acid contents of imported and Nova Scotia field and greenhouse tomatoes were 13.3, 16.7 and 17.7 mg 100 g−1 fresh weight, respectively. A study of nine recommended or promising field tomatoes for the Atlantic region showed significant differences in ascorbic acid content among the cultivars. The cultivar Quick Pick had the highest ascorbic acid content of 22.5 ± 1.5 mg 100 g−1, the cultivar Campbell 18 had the lowest content, 12.0 ± 2.9 mg 100 g−1. In Dombito greenhouse tomatoes the stage of maturity and the effect of cluster location were tested against ascorbic acid content. The lowest ascorbic acid content of 9.1 ± 1.0 mg 100 g−1 was found with the small green tomatoes while others from mature green to overripe contained 14.0–16.7 mg 100 g−1. Tomatoes from different cluster locations showed no significant difference in ascorbic acid content.Key words: Vitamin C, L-ascorbic acid, tomatoes

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Determinants of mRNA stability in Dictyostelium discoideum amoebae: differences in poly(A) tail length, ribosome loading, and mRNA size cannot account for the heterogeneity of mRNA decay rates.

Molecular and Cellular Biology ◽

10.1128/mcb.8.5.1957 ◽

1988 ◽

Vol 8 (5) ◽

pp. 1957-1969 ◽

Cited By ~ 23

Author(s):

R A Shapiro ◽

D Herrick ◽

R E Manrow ◽

D Blinder ◽

A Jacobson

Keyword(s):

Steady State ◽

Dictyostelium Discoideum ◽

Mrna Decay ◽

Decay Rates ◽

Time Dependent ◽

Translational Efficiency ◽

Cdna Clones ◽

Dependent Manner ◽

Significant Difference ◽

Kinetics Of

As an approach to understanding the structures and mechanisms which determine mRNA decay rates, we have cloned and begun to characterize cDNAs which encode mRNAs representative of the stability extremes in the poly(A)+ RNA population of Dictyostelium discoideum amoebae. The cDNA clones were identified in a screening procedure which was based on the occurrence of poly(A) shortening during mRNA aging. mRNA half-lives were determined by hybridization of poly(A)+ RNA, isolated from cells labeled in a 32PO4 pulse-chase, to dots of excess cloned DNA. Individual mRNAs decayed with unique first-order decay rates ranging from 0.9 to 9.6 h, indicating that the complex decay kinetics of total poly(A)+ RNA in D. discoideum amoebae reflect the sum of the decay rates of individual mRNAs. Using specific probes derived from these cDNA clones, we have compared the sizes, extents of ribosome loading, and poly(A) tail lengths of stable, moderately stable, and unstable mRNAs. We found (i) no correlation between mRNA size and decay rate; (ii) no significant difference in the number of ribosomes per unit length of stable versus unstable mRNAs, and (iii) a general inverse relationship between mRNA decay rates and poly(A) tail lengths. Collectively, these observations indicate that mRNA decay in D. discoideum amoebae cannot be explained in terms of random nucleolytic events. The possibility that specific 3'-structural determinants can confer mRNA instability is suggested by a comparison of the labeling and turnover kinetics of different actin mRNAs. A correlation was observed between the steady-state percentage of a given mRNA found in polysomes and its degree of instability; i.e., unstable mRNAs were more efficiently recruited into polysomes than stable mRNAs. Since stable mRNAs are, on average, "older" than unstable mRNAs, this correlation may reflect a translational role for mRNA modifications that change in a time-dependent manner. Our previous studies have demonstrated both a time-dependent shortening and a possible translational role for the 3' poly(A) tracts of mRNA. We suggest, therefore, that the observed differences in the translational efficiency of stable and unstable mRNAs may, in part, be attributable to differences in steady-state poly(A) tail lengths.

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