Cultivar-specific Apple Fruit Growth Rates in Vivo and Sink Activities in Vitro

Absolute and relative fruit growth rates (AGR and RGR) of apple (Malus domestics Borkh.) were calculated from the fruit dry weights of several cultivars harvested periodically following June drop during 1988-90. AGRs were constant or varied slightly, and RGRs generally declined as the season progressed. Generally, both AGR and RGR values were higher for relatively large fruit of several cultivars with similar days to maturity, e.g., `McIntosh' vs. `Jonathan' and for summervs. fall-ripening cultivars, e.g., `Stayman' vs. others. An exception was observed in 1990, when `Golden Delicious' exhibited a higher AGR but lower RGR than `Rome Beauty', yet ripened 1 month earlier. `Golden Delicious' AGR and RGR values were lower for both fruit of a pair on a spur than the values for a single fruit on a spur, and the dominant fruit of the pair exhibited higher growth rates than the inferior fruit. Rates of sorbitol accumulation (SAR) by cortex disks incubated in 14C-labeled sorbitol solutions in vitro declined as the season progressed. Within a cultivar, SARS were not related to fruit size, nor were differences found between cortex disks from competing fruit on a spur, although SARS were higher for both competing fruit on a spur as compared to that of a single fruit per spur. Due to a positive correlation between RGR and SAR values, the SAR of cortex cells may be regulated in such a manner as to be a physiological constraint on fruit sink strength and growth rate.

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CULTIVAR VARIATION IN APPLE FRUIT GROWTH RATES, SORBITOL ACCUMULATION, AND TISSUE OSMOTIC POTENTIAL

HortScience ◽

10.21273/hortsci.25.9.1070b ◽

1990 ◽

Vol 25 (9) ◽

pp. 1070b-1070

Author(s):

Dougles D. Archbold

Keyword(s):

Growth Rates ◽

Osmotic Potential ◽

Fruit Size ◽

Dry Weight ◽

Apple Fruit ◽

Cellular Level ◽

Fruit Growth ◽

Tissue Samples ◽

Uptake Rates

Absolute and relative fruit growth rates (AGR and RGR) of 5 cultivars were calculated from the oven-dry weights of fruits harvested periodically throughout the growing season. Both AGR and RGR were higher for larger fruit of different cultivars with similar days to maturity, and for summer- versus fall-ripening cultivars. Seasonal variability in AGR and RGR was observed, Apple fruit cortex disks were incubated in 14C-sorbitol solutions in vitro to determine if uptake rates at the cellular level varied between cultivars. Rates of sorbitol accumulation, expressed es μg sorbitol per mg dry weight cortex tissue, declined as the season progressed. Within a cuitivar, uptake rates were not relatad to fruit size, nor were differences found between cortex tissue samples from competing fruit on a spur. Sorbitol uptake rates were significantly lower for the more slowly-growing cultivar. The osmotic potential of the expressed cortex sap, sampled on several dates, was consistently lower for the more rapidly-growing cultivar. Thus, inherent differences in fruit growth rates among cultivars may be due to variation in regulation of osmotic potential.

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185 BIOASSAYS TO DETERMINE OF APPLE THINNING RESPONSE FROM APPLICATIONS OF NAA

HortScience ◽

10.21273/hortsci.29.5.455e ◽

1994 ◽

Vol 29 (5) ◽

pp. 455e-455

Author(s):

J. A. Flore ◽

M. Ventura ◽

D. Neri ◽

M. Sakin

Keyword(s):

Regression Analysis ◽

Growth Rates ◽

Environmental Conditions ◽

Fruit Size ◽

Fruit Growth ◽

Ethylene Evolution ◽

Fruit Drop ◽

Ethylene Response ◽

Golden Delicious ◽

Early Indicators

Auxin induction of ethylene, and fruit growth rates were investigated as early indicators of NAA thinning response for Golden Delicious, Red Delicious, McIntosh, Empire, and Tydeman's Red over a four period. Abscission at the end of the drop period was correlated with ethylene evolution from leaves 24-48 hours after NAA application and with changes in fruit growth at 2-3 day intervals through 10-14 days after application. Variation in ethylene evolution and fruit growth were also associated with environmental conditions prior to and at the time of NAA application to determine which factors have the greatest influence on response. Ethylene was a better predictor of final fruit drop than changes in fruit size for all varieties tested. However both performed very well. The ethylene bioassay requires more equipment, but the response is more-immediate. Bourse, and spur leaves as well as fruit were capable of producing ethylene in response to NAA application. Thinning response was greatest when all leaves and fruit were treated with NAA, followed by the bourse and spur leaves. Little or no response was produced when the fruit alone were treated. Concentration experiments and radioisotope data indicate that ethylene response is directly related to the amount of NAA absorbed. Regression analysis indicates that approximately 60% of the variation in response can be predicted by ethylene evolution

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699 PB 309 THE MODE OF CO2 ACTION ON ACC OXIDASE AND ITS ROLE IN INHIBITION OF ETHYLENE BIOSYNTHESIS

HortScience ◽

10.21273/hortsci.29.5.533b ◽

1994 ◽

Vol 29 (5) ◽

pp. 533b-533 ◽

Cited By ~ 5

Author(s):

James R. Gorny ◽

Adel A. Kader

Keyword(s):

Acc Oxidase ◽

Ethylene Biosynthesis ◽

Apple Fruit ◽

Cytosolic Ph ◽

Western Blots ◽

Golden Delicious ◽

Catalytic Capacity ◽

Acc Content

Ethylene biosynthesis of Golden Delicious apple fruit at 20°C is rapidly inhibited by a controlled atmosphere of air + 20% CO2. However, in vitro ACC oxidase activity and ACC content were not significantly different between air and air + 20% CO2 treated fruit, To determine the in vivo effects of CO2 treatment, both in vivo and in vitro enzyme activity essays were performed in en atmosphere of air or air + 20% CO2. Western blots were also performed to quantify the amount of ACC oxidase protein present in the air and air + 20% CO2 treated fruit. We believe that in vivo cytosolic pH changes, induced by CO2, may reduce the in vivo catalytic capacity of ACC oxidase, end hence significantly reduce ethylene biosynthesis in climacteric tissue,

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Elevated CO2 and/or Low O2 Atmospheres Influence ACC Synthase and ACC Oxidase during Long-term Storage of `Golden Delicious' Apple Fruit

HortScience ◽

10.21273/hortsci.30.4.782c ◽

1995 ◽

Vol 30 (4) ◽

pp. 782C-782

Author(s):

James R. Gorny ◽

Adel A. Kader

Keyword(s):

Blot Analysis ◽

Acc Oxidase ◽

Acc Synthase ◽

Ethylene Biosynthesis ◽

Apple Fruit ◽

Long Term Storage ◽

Golden Delicious ◽

Compare And Contrast

The objective of this study was to compare and contrast the mode of action by which elevated carbon dioxide and/or reduced oxygen atmospheres inhibit ethylene biosynthesis. `Golden Delicious' apple fruit were placed at 0C in one of the following four atmospheres: 1) air; 2) air + 5% CO2; 3) 2% O2 + 98% N2; or 4) 2% O2 + 5% CO2 + 93% N2 and then sampled monthly for 4 months. Ethylene biosynthesis rates and in vitro ACC synthase activities were closely correlated in all treatments. In vitro ACC synthase activity and ethylene biosynthesis rates were lowest in fruit treated with 5% CO2 + 2% O2, while air-treated fruit had the highest ethylene biosynthesis rate and in vitro ACC synthase activity. Fruit treated with air + 5% CO2, or 2% O2 + 98% N2, had intermediate ethylene and in vitro ACC synthase activities. In vitro ACC oxidase was significantly different among treatments, but not as closely correlated with the ethylene biosynthesis rate as in vitro ACC synthase activity. Western blot analysis of the ACC oxidase protein was performed to determine if activity differences among treatments were correlated with the amount of enzyme present in vivo. ACC synthase and ACC oxidase mRNA transcript of abundance was determined via Northern blot analysis. Results will be discussed regarding how ethylene biosynthesis is inhibited at the molecular level by elevated CO2 and/or reduced O2.

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Characterizing the Interaction between NAA and BA on Apple Fruit Abscission and Development

HortScience ◽

10.21273/hortsci.43.6.1794 ◽

2008 ◽

Vol 43 (6) ◽

pp. 1794-1801 ◽

Cited By ~ 3

Author(s):

Martin J. Bukovac ◽

Paolo Sabbatini ◽

Philip G. Schwallier ◽

Michael Schroeder

Keyword(s):

Strong Interaction ◽

Fruit Size ◽

Apple Fruit ◽

Fruit Growth ◽

Crop Load ◽

Fruit Thinning ◽

Small Fruit ◽

Golden Delicious ◽

Fruit Formation ◽

Fruit Diameter

NAA and BA are important compounds for regulating crop load in apples (Malus domestica Borkh.). When used for fruit thinning, both induce abscission, but at an equivalent crop load NAA tends to reduce and BA to increase fruit size. There is a strong interaction between NAA and BA when used together on ‘Delicious’ and ‘Fuji’, leading to excessive development of pygmy and small fruit (<65 mm diameter). The combination of BA (as Promalin, 1:1 BA + GA4+7) applied at king bloom (KB) and NAAm (amide) at petal fall increased the percentage of small fruit by 3.3- or 5.1-fold compared with BA or NAAm alone. Similar results were obtained with BA (Promalin) at KB oversprayed with NAA at 10 to 12 mm king fruit diameter (KFD). When NAA was oversprayed with BA during fruitlet development, i.e., 5 to 6 mm, 10 to 12 mm, and ≈18 mm KFD, the greatest inhibition of fruit growth occurred at the 10- to 12-mm KFD stage, and there was no significant effect at 18 mm KFD. Inhibition by treatment at the 5- to 6-mm stage was intermediate and trees were overthinned. NAA + BA inhibition of fruit growth in ‘Delicious’ and ‘Fuji’ was not crop load-dependent. In all experiments, crop load (wt basis) of trees treated with NAA + BA was similar or less than of those treated with NAA or BA alone, but they produced 2.5- to 5-fold more small fruit. NAA + BA increased the number of fruit per cluster, many of which failed to fully develop. Increasing the ratio of BA to NAA from 25:15 to 125:15 mg·L−1 increased small fruit formation. The presence of GA4+7 in commercial formulations of BA (0:100, Maxcel; 10:100, Accel; 50:50, Promalin) did not significantly affect the NAA + BA response. Fruit growth was not inhibited by the NAA + BA combination in large-fruited ‘Golden Delicious’ and ‘Jonagold’ and was increased in small-fruited ‘Elstar’ and ‘Gala’ compared with the nontreated control.

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The effect of the blue light on the pericarp cell growth and lycopene content of cherry tomato (Solanum lycopersicum var. cerasiforme) fruit

Science and Technology Development Journal - Natural Sciences ◽

10.32508/stdjns.v4i4.891 ◽

2020 ◽

Vol 4 (4) ◽

pp. First

Author(s):

Dien Thi Kieu Pham ◽

Kiet Thuong Do ◽

Sanh Du Nguyen

Keyword(s):

Blue Light ◽

Tomato Fruit ◽

Fruit Size ◽

Total Content ◽

Fruit Growth ◽

Cell Diameter ◽

Cherry Tomato ◽

Blue Filter ◽

Lycopene Content

The cherry tomato fruit size depends on the growth of the pericarp which is parenchymal cells. The blue light stimulates the expansion of cotyledon cells, hypocotyl cells and leaf cells. In this study, the cherry tomato fruit was used as a material to investigate the effects of the blue light on the pericarp cells growth in fruit growth stage and lycopene accumulation in fruit growth and ripening stage. After 7 days of the blue light (440, 450 or 460 nm) treatment, pericarp cells growth and physiological, biochemical changes of the pericarp cells of 7-day-old fruit pericarp piece in vitro were analyzed. The lycopene content and some organic compound contents of 42-day-old postharvest fruits treated by the blue light similarly in 7 days and 7, 21-day-old fruit wrapped with blue filter (440-510 nm filtered) in 7 days were measured. The results showed that the 450 nm wavelength blue light the increased pericarp thickness of 7-day-old fruits through the increasement of the pericarp cell diameter. The 460 nm wavelength blue light the increased lycopene content of 42-day-old postharvest fruits. The blue filter treatment increased the sugar total content of 7- day-old fruits and increased the lycopene content of 21-day-old fruits.

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Silver nanoparticles used to counter Monilinia fructicola fungicide-resistance and reduce fungicide environmental footprint

10.5194/egusphere-egu21-9285 ◽

2021 ◽

Author(s):

Constantinos Chrysikopoulos ◽

Anastasios A. Malandrakis ◽

Nektarios Kavroulakis ◽

Anthi Stefanarou

Keyword(s):

Silver Nanoparticles ◽

Control Plant ◽

Resistance Mutation ◽

Silver Ions ◽

Apple Fruit ◽

Ag Nps ◽

Gene Target ◽

Benzimidazole Fungicides

<div>The potential of silver nanoparticles (Ag-NPs) to control plant pathogen Moniliafructicola and to deter environmental contamination by reducing fungicide doses was evaluated in vitro and in vivo. &#160;Fungitoxicity screening of&#160;M. fructicola&#160;isolates resulted in the detection of 18 benzimidazole-resistant (BEN-R) isolates with reduced sensitivity to fungicides &#160;thiophanate methyl (TM)&#160; and carbendazim. All resistant isolates caried the E198A resistance mutation in their &#946;-tubulin gene, target site of the benzimidazole fungicides.&#160;Ag-NPs could effectively control both sensitive (BEN-S) and resistant isolates while the combination of Ag-NPs with TM significantly enhanced their fungitoxic effect both in vitro&#160;and in apple fruit tests. The positive correlation observed between Ag-NPs and TM+Ag-NPs treatments indicates a mixture-enhanced Ag-NPs activity/availability as a possible mechanism of synergy. No correlation between Ag-NPs&#160; and AgNO3&#160;could&#160; be found suggesting difference(s) in the fungitoxic mechanism of action between Nps and their bulk/ionic counterparts. Indications of the involvement of energy (ATP) metabolism in the mode of action of Ag-NPs were also evident by the synergy observed between Ag-NPs and the oxidative phosphorylation-uncoupler fluazinam (FM) against both BEN-R and BEN-S phenotypes. The role of silver ions release on the inhibitory action of Ag-NPs against the fungusis probably limited since the AgNPs/NaCl combination enhanced fungitoxicity, a fact that could not be justified by the expected binding of silver with chlorine ions. Concluding, Ag-NPs can be effectively used as a means of controlling both BEN-S and BEN-R M.&#160;fructicola&#160;isolates while&#160;their combination with conventional fungicides should aid anti-resistant strategies and reduce the environmental impact of synthetic fungicides by reducing effective doses to the control the pathogen.</div>

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Indole-3-Acetic Acid Improves Postharvest Biological Control of Blue Mold Rot of Apple by Cryptococcus laurentii

Phytopathology ◽

10.1094/phyto-99-3-0258 ◽

2009 ◽

Vol 99 (3) ◽

pp. 258-264 ◽

Cited By ~ 22

Author(s):

Ting Yu ◽

Jishuang Chen ◽

Huangping Lu ◽

Xiaodong Zheng

Keyword(s):

Acetic Acid ◽

Apple Fruit ◽

Natural Resistance ◽

Penicillium Expansum ◽

Cryptococcus Laurentii ◽

Blue Mold ◽

Biocontrol Efficacy ◽

Indole 3 Acetic Acid

Cryptococcus laurentii is a well-known postharvest biocontrol yeast; however, it cannot provide satisfactory levels of decay control when used alone. Here, we evaluated the effects of indole-3-acetic acid (IAA), a plant growth regulator, on the biocontrol efficacy of the yeast antagonist C. laurentii against blue mold rot caused by Penicillium expansum in apple fruit. Results showed that the addition of IAA at 20 μg/ml to suspensions of C. laurentii greatly enhanced inhibition of mold rot in apple wounds compared with that observed with C. laurentii alone. The addition of IAA at 20 μg/ml or lower did not influence the population growth of C. laurentii in wounds, but adverse effects were seen on C. laurentii when the concentration of IAA was increased to 200 μg/ml or above in vitro and in vivo. P. expansum infection in apple wounds was not inhibited when the pathogen was inoculated into the fruit wounds within 2 h after application of IAA; however, infection was reduced when inoculated more than 12 h after IAA application. Treatment of wounds with IAA at 20 μg/ml 24 h before pathogen inoculation resulted in significant inhibition of P. expansum spore germination and host infection. Application of IAA at 20 μg/ml also reduced P. expansum infection when it was applied 48 h before pathogen inoculation in the intact fruit. Thus, IAA could reinforce the biocontrol efficacy of C. laurentii in inhibiting blue mold of apple fruit by induction of the natural resistance of the fruit.

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In vitro Fibre production and protein deposition in secondary hair follicles of the cashmere and angora goat

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s030822960002763x ◽

1994 ◽

Vol 1994 ◽

pp. 219-219

Author(s):

D R Lee ◽

H Galbraith ◽

J R Scaife

Keyword(s):

Growth Rates ◽

Fibre Production ◽

Culture Technique ◽

Fibre Volume ◽

Hair Follicles ◽

Winter Solstice ◽

Protein Deposition ◽

Angora Goat

Hair fibre represents an important biological process to many feral and domesticated animals, both for environmental protection and as an aid to thermoregulation. Mohair which is the fine fibre produced by secondary hair follicles of the Angora goat grows essentially independent of season, with typical growth rates of 0.5-1 .0mm/day and annual yields typically 2-3kg. In contrast, down production from secondary hair follicles of double coated goats, classified as cashmere, is dependent on season. Fibre grows from around the summer to the winter solstice or later, with growth rates in this period of 0.3-0.7mm/day and annual yields maximally 600g but typically less than 100g. Questions arise as to how the seasonal stimuli affect fibre growth, and what determines the differences in fibre production between the two genotypes at the follicle level.In the work described here, based on the in vitro isolation and culture technique developed for the Angora and Cashmere goats by Ibraheem et al (1993, 1992 repectively) we have compared fibre volume produced in vivo and in vitro, examined the DNA concentration and protein depositional capacities of mohair and cashmere secondary follicles. In addition the effects of the hormones prolactin and melatonin as mediators of photoperiod in vivo, on in vitro protein deposition in mohair and cashmere secondary hair follicles are also examined.

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Long-term passage of tachyzoites in tissue culture can attenuate virulence of Neospora caninum in vivo

Parasitology ◽

10.1017/s0031182006000539 ◽

2006 ◽

Vol 133 (4) ◽

pp. 421-432 ◽

Cited By ~ 47

Author(s):

P. M. BARTLEY ◽

S. WRIGHT ◽

J. SALES ◽

F. CHIANINI ◽

D. BUXTON ◽

...

Keyword(s):

Tissue Culture ◽

Body Weight ◽

Growth Rates ◽

Clinical Symptoms ◽

Neospora Caninum ◽

High Passage ◽

Low Passage

To determine whether prolonged in vitro passage would result in attenuation of virulence in vivo, Neospora caninum tachyzoites were passaged for different lengths of time in vitro and compared for their ability to cause disease in mice. Groups of Balb/c mice were inoculated intraperitoneally with 5×106 or 1×107 of low-passage or high-passage N. caninum tachyzoites. The mice were monitored for changes in their demeanour and body weight, and were culled when severe clinical symptoms of murine neosporosis were observed. Mice inoculated with the high-passage parasites survived longer (P<0·05), and showed fewer clinical symptoms of murine neosporosis, compared to the mice receiving the low-passage parasites. The parasite was detected in the brains of inoculated mice using immunohistochemistry and ITS1 PCR. Tissue cysts containing parasites were seen in mice inoculated with both low-passage and high-passage parasites. When the in vitro growth rates of the parasites were compared, the high-passage parasites initially multiplied more rapidly (P<0·001) than the low-passage parasites, suggesting that the high-passage parasites had become more adapted to tissue culture. These results would suggest that it is possible to attenuate the virulence of N. caninum tachyzoites in mice through prolonged in vitro passage.

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