Control of Postharvest Gray Mold of Table Grapes in the San Joaquin Valley of California by Fungicides Applied During the Growing Season

Fungicides applied before harvest were evaluated to control postharvest gray mold of table grapes, caused by Botrytis cinerea. The concentrations of thiophanate methyl (THM), iprodione (IPR), cyprodinil (CYP), pyraclostrobin + boscalid (PS+BO), pyrimethanil (PYR), or fenhexamid (FEN) that inhibited the growth of four isolates sensitive to these fungicides by 50% (EC50) were 12.4, 2.5, 0.61, 0.29/0.57, 0.26, or 0.17 mg liter-1, respectively. THM, IPR, CYP, PS+BO, PYR, or FEN were applied to detached ‘Thompson Seedless’ berries at the equivalent of the maximum approved rates of 600, 500, 270, 59/116, 370, or 290 mg liter-1, respectively, except PS+BO, which were used at 54.2% of their current registered maximum rates. The berries were inoculated with B. cinerea 48 or 24 h before treatment or 24 or 48 h after treatment. Gray mold 2 weeks after treatment and storage at 15°C was lowest after FEN application, followed by PYR, CYP, IPR, PS+BO, and THM. In commercial vineyards, one application of FEN, PYR, CYP, or PS+BO, all at their current maximum approved rates, 2 weeks before harvest reduced postharvest gray mold by approximately 50%. When fungicides were applied repeatedly after berry set either in mixtures or alternated with fungicides of different mode of action classes, postharvest gray mold was reduced by about 50% using a commercial air-blast sprayer and by 70 to 87% using a hand-held sprayer that was directed into the clusters. The fungicide sensitivity of isolates collected in numerous vineyards indicated those with reduced sensitivity to all of the tested fungicides, except FEN, were common. The efficacy of preharvest fungicide regimes was not sufficient to replace postharvest sulfur dioxide fumigation.

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Preharvest Fungicide, Potassium Sorbate, or Chitosan Use on Quality and Storage Decay of Table Grapes

Plant Disease ◽

10.1094/pdis-12-11-1043-re ◽

2013 ◽

Vol 97 (3) ◽

pp. 307-314 ◽

Cited By ~ 28

Author(s):

E. Feliziani ◽

J. L. Smilanick ◽

D. A. Margosan ◽

M. F. Mansour ◽

G. Romanazzi ◽

...

Keyword(s):

Gray Mold ◽

Potassium Sorbate ◽

Thompson Seedless ◽

Berry Skin ◽

Grape Berries ◽

Table Grapes ◽

Berry Quality ◽

Seedless Grape ◽

And Storage ◽

Natural Incidence

Potassium sorbate, a program of four fungicides, or one of three chitosan formulations were applied to clusters of ‘Thompson Seedless’ grape berries at berry set, pre-bunch closure, veraison, and 2 or 3 weeks before harvest. After storage at 2°C for 6 weeks, the natural incidence of postharvest gray mold was reduced by potassium sorbate, the fungicide program, or both together in a tank mixture, in 2009 and 2010. In 2011, the experiment was repeated with three chitosan products (OII-YS, Chito Plant, and Armour-Zen) added. Chitosan or fungicide treatments significantly reduced the natural incidence of postharvest gray mold among grape berries. Berries harvested from vines treated by two of the chitosan treatments or the fungicide program had fewer infections after inoculation with Botrytis cinerea conidia. None harmed berry quality and all increased endochitinase activity. Chitosan decreased berry hydrogen peroxide content. One of the chitosan formulations increased quercetin, myricetin, and resveratrol content of the berry skin. In another experiment, ‘Princess Seedless’ grape treated with one of several fungicides before 4 or 6 weeks of cold storage had less decay than the control. Fenhexamid was markedly superior to the other fungicides for control of both the incidence and spread of gray mold during storage.

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BiofumigationwithMuscodoralbus Pads for Controlling Decay in Commercial Table Grape Cartons

HortScience ◽

10.21273/hortsci.40.4.1144d ◽

2005 ◽

Vol 40 (4) ◽

pp. 1144D-1144 ◽

Cited By ~ 4

Author(s):

Julien Mercier ◽

Paul Walgenbach ◽

Jorge I. Jiménez

Keyword(s):

Isobutyric Acid ◽

Gray Mold ◽

Fruit Weight ◽

Table Grape ◽

Fungal Decay ◽

Isobutyl Alcohol ◽

Thompson Seedless ◽

Significant Control ◽

Table Grapes ◽

And Control

The volatile-producing fungus Muscodoralbus is being developed as a biological fumigant for postharvest use, as it can kill storage pathogens and control fungal decay in various commodities. A wettable pad or sachet system made of teabag paper containing desiccated rye grain culture of M. albus was designed for the biofumigation of individual fruit containers. The fungus is reactivated before use by a brief immersion of the pad in water. This research was conducted to determine the potential of the pad system for controlling decay of table grapes in commercial cartons. Individual pads containing 24 or 86 g of grain culture (to achieve a 1:10 ratio of fumigant to box volume or a 1:100 ratio of fumigant to fruit weight, respectively) were added to Styrofoam cartons containing 8.6 kg of freshly harvested `Thompson Seedless' (TS) or `Ruby Seedless' (RS) grapes, which were then placed in cold storage at –1 to 0 °C. Control cartons exposed to SO2 were placed in a separate storage room and SO2 fumigation was performed once for TS and weekly for RS. After 8 to 9 weeks, the grapes were taken out of storage and rated for decay. In the experiment with TS, the 24-g and 86-g pads provided significant control of gray mold rot when compared to untreated cartons and were not statistically different from cartons exposed to a single SO2 fumigation. In the experiment with RS, only the 86-g pads provided significant decay control. Measurements of the three most abundant volatile compounds in empty cartons containing 10 g of the biofumigant revealed that partial coverage of holes mimicking obstruction by packed fruit achieved levels of isobutyl alcohol, 2-methyl-1-butanol, and isobutyric acid of 0.7, 1.6, and 11.2 ppb, respectively.

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Gibberellic Acid Application Timing Influences the Bud Viability and Fruitfulness of Seedless Table Grape Cultivars

HortScience ◽

10.21273/hortsci.31.4.598c ◽

1996 ◽

Vol 31 (4) ◽

pp. 598c-598 ◽

Cited By ~ 1

Author(s):

N.K. Dokoozlian

Keyword(s):

Gibberellic Acid ◽

Table Grape ◽

Thompson Seedless ◽

Application Timing ◽

Table Grapes ◽

Grape Cultivars ◽

Berry Set

A study initiated in Spring 1995 examined the influence of gibberellic acid (GA3) application timing on the return fruitfulness of Thompson Seedless and Flame Seedless table grapes. Vines treated with GA3 at prebloom, bloom, or berry set were compared to vines treated at prebloom + bloom + berry set and nontreated vines. Application amounts for each cultivar and timing were based on commercial label recommendations. Nodes from each treatment were collected in mid-winter and dissected, and their viability and fruitfulness were recorded. Bud viability (shoots per bud) and fruitfulness (clusters per shoot) also were evaluated at budbreak in 1996. The results indicate that GA3 applications at prebloom and bloom are most detrimental to bud viability and cluster initiation in these cultivars.

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Biological indicators to estimate the prevalence of gray mold and hairline cracks on table grapes cv. Thompson Seedless after cold storage

Postharvest Biology and Technology ◽

10.1016/j.postharvbio.2008.11.010 ◽

2009 ◽

Vol 52 (1) ◽

pp. 126-133 ◽

Cited By ~ 10

Author(s):

Juan Pablo Zoffoli ◽

Bernardo A. Latorre ◽

Jessica Rodriguez ◽

José M. Aguilera

Keyword(s):

Cold Storage ◽

Biological Indicators ◽

Gray Mold ◽

Thompson Seedless ◽

Table Grapes

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Identification of epiphytic yeasts and bacteria with potential for biocontrol of grey mold disease on table grapes caused by Botrytis cinerea

Spanish Journal of Agricultural Research ◽

10.5424/sjar/2018161-11378 ◽

2018 ◽

Vol 16 (1) ◽

pp. e1002 ◽

Cited By ~ 4

Author(s):

Kazem Kasfi ◽

Parissa Taheri ◽

Behrooz Jafarpour ◽

Saeed Tarighi

Keyword(s):

Botrytis Cinerea ◽

Disease Incidence ◽

Gray Mold ◽

Antagonistic Activity ◽

Antagonistic Effect ◽

Bacterial Isolates ◽

Thompson Seedless ◽

Grape Berries ◽

Table Grapes

The objective of this study was to identify grapevine epiphytic yeasts and bacteria for biocontrol of Botrytis cinerea on grapes. Antagonistic yeasts and bacteria were isolated from the epiphytic flora associated with grape berries and leaves cv. ‘Thompson seedless’ from vineyards in Iran and identified by sequencing the conserved genomic regions. A total of 130 yeast and bacterial isolates from the surface of grapevine were screened in vitro for determining their antagonistic effect against B. cinerea and used to control postharvest gray mold. Among the 130 isolates, five yeasts and four bacterial isolates showed the greatest antagonistic activity in vitro against B. cinerea. Two yeasts species including Meyerozyma guilliermondii and Candida membranifaciens had high antagonistic capability against the pathogen. Also, 4 bacterial isolates belonging to Bacillus sp. and Ralstonia sp. showed significant biocontrol effect against B. cinerea. The isolates were capable of producing volatile and non-volatile substances, which suppressed the pathogen growth. The antagonistic activity of selected yeasts and bacteria against the pathogen was investigated on wounded berries of ‘Thompson seedless’. On small clusters with intact berries, all of the antagonistic isolates considerably reduced the decay on grape berries and inhibition of gray mold incidence on fruits treated by these isolates was less than 50%, except for the isolate N1, which had higher capability in inhibiting the disease incidence. These results suggest that antagonist yeasts and bacteria with potential to control B. cinerea on grape can be found in the microflora of grape berries and leaves.

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Preharvest Chitosan and Postharvest UV Irradiation Treatments Suppress Gray Mold of Table Grapes

Plant Disease ◽

10.1094/pd-90-0445 ◽

2006 ◽

Vol 90 (4) ◽

pp. 445-450 ◽

Cited By ~ 81

Author(s):

G. Romanazzi ◽

F. Mlikota Gabler ◽

J. L. Smilanick

Keyword(s):

Chitinase Activity ◽

Gray Mold ◽

Grape Berry ◽

Thompson Seedless ◽

Berry Skin ◽

Grape Berries ◽

Table Grapes ◽

Ultraviolet C ◽

Berry Skins ◽

Uv C

The effectiveness of chitosan treatment of table grapes, alone or in combination with ultraviolet-C (UV-C) radiation, to control postharvest gray mold caused by Botrytis cinerea, was determined in California, United States. The influence of these treatments on catechin and resveratrol contents and chitinase activity in grape berry skins also was assessed. Clusters of cvs. Thompson Seedless, Autumn Black, and Emperor were sprayed in the vineyard with 1% chitosan, then harvested daily for 5 days. Promptly after harvest, they were inoculated with B. cinerea. Decay incidence and disease severity were significantly reduced by chitosan, which was most effective on berries harvested 1 or 2 days after treatment. In another experiment, grape berries were sprayed in the vineyard with chitosan, harvested 2 days later, irradiated for 5 min with UV-C (0.36 J/cm2), and inoculated with B. cinerea 2 days later. Combined chitosan and UV-C treatments applied to cv. Autumn Black or selection B36-55 were synergistic in reducing gray mold incidence and severity compared with either treatment alone. Preharvest chitosan treatment increased neither concentration of catechin or resveratrol nor activity of chitinase in berry skin. Conversely, UV-C irradiation, alone or combined with chitosan treatment, induced catechin in cv. Autumn Black berries and trans-resveratrol in both cv. Autumn Black and selection B36-55.

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Barley seed storage under controlled conditions

Genetičnì resursi roslin (Plant Genetic Resources) ◽

10.36814/pgr.2019.25.11 ◽

2019 ◽

pp. 140-150 ◽

Cited By ~ 1

Author(s):

O. A. Zadorozhna ◽

T. P. Shyianova ◽

M.Yu. Skorokhodov

Keyword(s):

Hordeum Vulgare ◽

Moisture Content ◽

Spring Barley ◽

Seed Storage ◽

Growing Season ◽

Storage Conditions ◽

Meteorological Conditions ◽

Hordeum Vulgare L ◽

The Relationship ◽

And Storage

Seed longevity of 76 spring barley gene pool samples (Hordeum vulgare L. subsp. distichon, convar. distichon: 56 nutans Schubl., two deficience (Steud.) Koern., two erectum Rode ex Shuebl., two medicum Koern.; convar. nudum (L.) A.Trof.: one nudum L. та subsp. vulgare: convar. vulgare: nine pallidum Ser., three rikotense Regel.; convar. coeleste (L.) A.Trof.: one coeleste (L.) A.Trof.) from 26 countries, 11 years and four places of reproduction was analyzed. Seeds with 5–8% moisture content were stored in chamber with unregulated and 4oC temperature. The possibility of seed storage under these conditions for at least 10 years without significant changes in germination has been established. The importance of meteorological conditions in the formation and ripening of seeds for their longevity is confirmed. The relationship between the decrease of barley seeds longevity and storage conditions, amount of rainfall, temperature regime during the growing season of plants is discussed.

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Effect of aminoethoxyvinylglycine (AVG) on quality, berry set and coloration of ‘Alphonse Lavallée’ table grapes

The Journal of Agricultural Science ◽

10.1017/s0021859621000496 ◽

2021 ◽

pp. 1-7

Author(s):

Zehra Babalık

Keyword(s):

Ethylene Biosynthesis ◽

Grape Berry ◽

Soluble Solids ◽

Anthocyanin Content ◽

Quality Properties ◽

Table Grapes ◽

Colour Parameters ◽

Length Width ◽

Solids Content ◽

Berry Set

Abstract The effect of different concentrations of aminoethoxyvinylglycine (AVG; 0 (control), 250, 500, 750 and 1000 mg/l), an ethylene biosynthesis inhibitor, on grape berry set and fruit quality was evaluated under vineyard conditions. Treatments were performed on ‘Alphonse Lavallée’ grape cultivar at full bloom stage for two years. Cluster and berry growth (length, width and weight), firmness, soluble solids content, yield, berry set, anthocyanin content and colour parameters were determined on treated and untreated (control) fruits. As a result of the study, the effects of AVG concentrations on firmness were not significant. When AVG applications were compared with control, it is determined that some quality properties were statistically affected, the others were not. Fruit set was increased by lower concentrations of AVG (250 mg/l) and anthocyanin content was increased by higher concentrations of AVG (750 mg/l).

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