Vine sprays

Figure 2. Zinfandel grape clusters at harvest, from vines sprayed April 28 with KGAS...

One Thompson Seedless and one Black Corinth vine, sprayed after flowering in two consecutive years, respectively, showed no visible injury from KGA3 at 1000 and 100 p.p.m. Thus, high concentrations are not toxic to the seedless varieties studied, although far lower concentrations are highly toxic to the seeded varieties studied. A generalization must await tests with more varieties. 

Table IV. Growth of Shoots on April 19, 1958, on Zinfandel Vines Sprayed Previous Autumn with KGA3...

As there was an excess of resin compared to the amount of cations in the wine, stoichiometric H+ ions were released in exchange and assayed using sodium hydroxide. Wine contains the cations naturally present in grapes, with the addition of manganese and zinc, originating from vine sprays containing fungicides such as dithiocarbamates. 

Finally, it has been reported that some vine sprays may have an unexpected impact on the varietal aromas of wines. In particular, owing to the reactivity of thiols with copper, the apphcation of copper-based prodncts on Sauvignon Blanc and Cabernet Sanvignon vines results in a significant decrease in the aroma of young wines made from these grape varieties (Hatzidimitriou et al., 1996 Darriet et al, 2001). 

This section deals with those reduction defects attributable to vine sprays containing elemental sulfur and various fungicides or insecticides. The risk of sulfur compounds developing due to thermal or photochemical mechanisms ( sunlight flavor ) is also discussed. 

Volatile Sulfur Compounds from Vine Sprays... 

Wbat to do Early in the growing season, cover vines with row cover or mesh uncover later for pollinators, or hand-pollinate flowers. To save attacked vines, slit infested stems and remove the borers, then heap soil over the vines to induce rooting. If squash vine borers have been a serious problem in previous years, spray the base of susceptible plants with pyrethrin to kill young larvae before they enter vines. 

Since the five seeded varieties were similar in response, they are represented herein by Red Malaga, various vines of which were sprayed in 1957 with gibberellin at one of three stages (prebloom, full bloom, and after berry shatter). Shoots and clusters were counted in April of 1958 and 1959, and crop weights were measured in September or October. Since the results were essentially alike, regardless of spray date, only results of the full-bloom spraying are presented here (Table II). 

Prebloom sprays of gibberellin also hasten flowering. Sprayed vines flower 3 or 4 days earlier than the unsprayed. In some varieties such as Zinfandel, ripen-... 

When gibberellin is sprayed on seeded vines during the summer or fall, foliation is often delayed in the following spring. Such sprays may be valuable to retard bud break in the spring and protect against early frost injury. Further work must be done on this phase, however. 

It is important to note that calling wine organic does not guarantee that it is 100% pure and free from pesticides and chemicals. The water the vines will use is likely to carry some pollution, there is the chance of spray drift from conventional vineyards nearby, and some chemicals are allowed in organic winemaking. Principally, organic... 

Alanycarb is a stomach poison and contact insecticide used as a foliar spray, soil treatment, or seed treatment for control of coleopterous, hemipterous, lepidopterous, and thy-sanopterous pests in corn, cotton, peanuts, vines, pome fruits, soybeans, sorghum, tea, sugar beet, vegetables, turf, and ornamentals. Its oral LD30 in rats is 440 mg/kg. 

The presence of other plants, such as tree or vine rows, or shelter belts, has a considerable influence on the distance that small spray droplets travel, or in the interception of spray in general. Modelling distribution of spray deposits in such environments is much more complex aud is not yet at a stage that it can be applied to operational situations. The usability to do so will lead to improvements in the deposition of spray within a spray area, as well as within the canopy, and it will be used to define spray drift interception. This could become an important part of spray mitigation management plans, especially relevant to the use in horticulture of relatively hazardous insecticides. 

Leaves with a white powdery coating on. ike surfaces. Cause Powdery mildew, jne-cred leaves eventually become distorted, un r w a. and fall. Dark patches appear on 3BK5. TMs fungal disease weakens vines, dimin-ines > eld. and makes plants more suscepti-"m winter injury. More common in the t spreads fastest when days are dry and am and nights are cool. For susceptible nar ings. apply sulfur spray in the spring. 

Grape scales are tiny, round, immobile insects resembling light gray bumps. Scales usually hide under the loose bark of older canes or trunks, where they suck sap and cause the vine to slowly decline. For control, spray with dormant oil in late winter and prune old growth severely. 

Leaves with notched edges. Cause Black vine weevils. The wingless. Vs", brownish black adults feed on the leaves and bark and can kill branches. See the opposite page for an illustration of this pest. To control them, try spreading a dropcloth around your plants, then shaking the plants the adults will drop and can be removed and destroyed. Spray leaves several times with pyrethrin for major infestations. The small, curved, white grubs of these weevils feed on the roots drench the soil around... 

Vines wilt suddenly. Cause Squash vine borers. These fat, white, 1" long larvae burrow into the stems and exude masses of yellow-green, sawdustlike excrement. For an illustration of this pest, see page 214. Slit stems lengthwise above injury with a sharp knife and kill larvae. Cover cut stems with moist soil so they will form new roots. Injecting stems with BTK or parasitic nematodes may also control borers. To reduce problems, plant the cultivar Sweet Mama Hybrid , which is resistant to vine borers. Or spray base of stems with BTK once a week in late spring and early summer. 

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