Beauty Seedless Research Articles

In vitro Growth and Leaf Composition of Grapevine Cultivars as Affected by Sodium Chloride

In vitro proliferated shoot culture of six grape genotypes (Vitis vinifera L.) were screened for tolerance to NaCl (0 to 200 mM). The cv. Perlette was found to tolerate 175 mM NaCl followed by cvs. Pusa Seedless and Beauty Seedless 150 mM NaCl. Na, K, Cl, Ca and Mg content increased upto 100 mM NaCl in most of the genotypes. Total sugar and proline content of stem tissue gradually increased under NaCl stress while leaf chlorophyll a+b content declined. Studies suggest that the in vitro screening procedure can be used for ranking the grape genotypes for salinity tolerance.

`Fantasy Seedless': A New Black Seedless Grape

‘Fantasy Seedless’ grape (Vitis vinifera L.) (Fig. 1) is a midseason, attractive, blue-black, referred to as black in the industry, seedless grape with naturally large berries. This grape was introduced in 1989 to fill the need for a black seedless cultivar for the fresh market. The California table grape industry has made dramatic strides in producing more seedless grapes. In 1982, 61.4% (31,300,000 boxes; box = 10 kg) of the grapes produced for the fresh market were seedless, compared to 80.0% (50,100,000 boxes) in 1992 (California Table Grape Commission, 1983, 1993). The development and release of ‘Flame Seedless’, a red grape (Weinberger and Harmon, 1974), in 1973 by the U.S. Dept. of Agriculture (USDA) played a significant role in this change. Since its inception in 1923 (Snyder, 1931, 1937), one of the objectives of the USDA grape breeding program in Fresno, Calif., has been to develop seedless grapes. However, since 1975, as a result of consumer demand, the development of seedless cultivars has become the most important objective. White seedless grapes (i.e., ‘Perlette’, ‘Superior Seedless’, and ‘Thompson Seedless’) are available most of the season. ‘Flame Seedless’ is available from May to October, ripening at various times in California’s grape production districts. However, few black grapes are being produced. In 1992, most black grapes shipped were ‘Ribier’ (877,000 boxes) and ‘Exotic’ (661,000), both of which have seeds (California Table Grape Commission, 1993). A few black seedless grapes have been introduced, but they have not become major cultivars. Among these is ‘Beauty Seedless’ (174,000 boxes shipped in 1992), which has been planted principally in the Coachella Valley of southern California for the early market. Also, ‘Black Monukka’ has been grown for the fresh market, but it shatters badly and is not economical to produce. Other minor black seedless cultivars are ‘Negrita’ (5600 boxes) and ‘Majestic’ (97,000 boxes).

Glutathione Increases in Grape Berries at the Onset of Ripening

Glutathione (GSH) was measured in grape (<i>Vitis vinifera</i> L.) berries during ripening. The Thompson Seedless variety was studied during two consecutive seasons from just before the onset of sugar accumulation until the berries attained commercial maturity. The GSH content increased along with soluble solids in both years. From Julian day 173 to day 197 in 1990 (21 June to 15 July), the GSH increased from 28.8 nmoles/gFW to 319 nmoles/ gFW. The average fresh weight of the berries increased from 0.79 g/berry to 1.95 g/berry during this period, so the GSH increase on a per berry basis was 22.4 nmoles/berry to 639 nmoles/berry. An increase in GSH was also observed in berries of Perlette, another seedless table grape variety. Beauty Seedless, a red variety, showed a gain in GSH accompanying the increase in soluble solids which began with the onset of pigmentation. Pigmented berries on a turning cluster showed higher GSH than green berries on the same cluster. Likewise, a seeded wine variety (Cabernet Sauvignon) had more GSH in berries with higher soluble solids, and more in pigmented berries on a turning cluster than in green berries from the same cluster. The results show that there is an increase in glutathione at the onset of ripening in grape berries. The increase was observed in red, green, seeded and seedless varieties, so GSH accumulation may be a general feature of grape berry ripening. The source of the GSH and a possible explanation for the timing of this phenomenon is discussed.

Biology and Control of the Grape Bud Beetle, Glyptoscelis squamulata (Coleoptera: Chrysomelidae), in Southern California Table Grapes

Glyptoscelis squamulata, often called the grape bud beetle (GBB), is indigenous to North America. During the 1920’s and into the late 1940’s this univoltine species was considered the major pest of fresh table grapes in the Coachella Valley of southern California. Adult beetles feed on emerging buds and eat the immature leaves and flower cluster primordia. The larval stages are spent in the soil feeding on roots. The beetle has reappeared recently as a major pest of grapes. Adult emergence from the soil was monitored in five Coachella Valley vineyards. Peak emergence occurs in the last three weeks of March. Early-budding varieties such as ‘Perlette,’ ‘Cardinal,’ and ‘Beauty Seedless’ may suffer less damage than the late-developing ‘Thompson Seedless.’ Adults are active at night, making detection difficult with a flashlight. We found that the beetles glow a bright silver blue under ultraviolet light; detection can be made in seconds. Feeding and oviposition studies were conducted. Phosmet, azinphosmethyl, and dimethoate were applied for control of adult beetles at 1.41, 1.41, and 2.25 kg (AI)/ha, respectively. They gave statistically similar results and caused significantly higher mortality than diazinon and carbaryl, which were both applied at 1.80 kg (AI)/ha.

ANTHOCYANINS OF BEAUTY SEEDLESS GRAPES

Beauty Seedless grape pigments were isolated and identified by chromatographic, spectral and chemical properties. The pigments were identified as delphinidin‐3‐glucoside, petunidin‐3‐glucoside, malvidin‐3‐glucoside, peonidin‐3‐glucoside, malvidin‐3‐glucoside acylated with caffeic acid and malvidin‐3‐glucoside acylated with p‐coumaric acid. Beauty Seedless grapes contained 62 mg anthocyanins per 100g fresh grapes and malvidin derivatives accounted for 73% of the total anthocyanins.

A PROCEDURE FOR QUANTITATIVE ESTIMATION OF MALIC AND TARTARIC ACIDS OF GRAPE JUICE

The ion‐exchange behaviors of succinic, malic and tartaric acids on Amberlite resins are evaluated. Retention and detector response data on silyl derivatives of several organic acids are presented. A procedure for the purification of grape juice by use of ion‐exchange resins prior to gas chromatography is described. The malic and tartaric acid contents (g/100 ml juice) respectively, of commercially acceptable grapes were found to be: Thompson Seedless 0.25, 0.90; Cardinal 0.31, 0.91; Beauty Seedless 0.19, 0.62; Perlette 0.26, 0.97; Exotic 0.27, 0.36; and Robin 0.41, 0.37.

The Glucose-Fructose Ratio ofVitis ViniferaGrapes

Concentrations of glucose, fructose, and total soluble solids in the fruits of 28 table varieties, 26 red wine varieties, and 24 white wine varieties of <i>Vitis vinifera</i> L. were determined at an early and a late stage of maturity. All fruits were from virus-free vines grown at Davis, California. The glucose-fructose ratio of table varieties ranged from 0.74 to 0.97 (mean 0.91 for the slightly to moderately ripe fruits, and 0.83 for the very ripe to overripe fruits). The ratio for the wine varieties ranged from 0.74 to 1.05 (mean 0.94 for the early-harvested fruits, and 0.85 for the late-harvested fruits). In every variety there was either a decrease or no change in the glucose-fructose ratio between the early- and the late-harvested fruits. Table varieties with relatively high amounts of fructose (glucose-fructose ratio less than 0.9) included Beauty Seedless, Black Corinth, Canner, Early Muscat, July Muscat, Loose Perlette, Niagara, Perlette and Black Monukka. High-fructose wine varieties were Chardonnay, Chasselas doré, Feher Szagos, Green Hungarian, Pinot blanc, Pinot gris and Red Veltliner. Varieties that were relatively high in glucose (glucose-fructose ratio greater than 0.9) at the late stage of fruit maturity were Exotic, Malaga, and Muscat of Alexandria table varieties, and Burger, Chenin blanc, Early Burgundy, Emerald Riesling, Flora, Grey Riesling, La Rienha and Zinfandel wine varieties. The glucose-fructose ratios of mature fruits from six varieties were lower during the warm 1966 season than during the cooler 1964 and 1965 seasons.