Vine Vigor Research Articles

Influence of Spacing on Fruit Yields and Quality of Grape Cultivars Differing in Vine Vigor

Abstract Five grape cultivars (Vitis spp.) varying in vine vigor were planted at 4 spacings (1.8 m × 1.8 m, 1.8 m × 2.7 m, 2.7 m × 1.8 m, 2.7 m × 2.7 m) on a Trafalgar silty clay loam soil in Ontario. In each of the first 5 harvest years (years 3 through 7 following planting), lowest yields per vine were obtained from the closest spacing (1.8 m × 1.8 m) but the increased plant number at this spacing resulted in highest yields/ha. Fruit quality, as evidenced by soluble solids and titratable acidity, was not adversely affected by close spacing. There was a greater reduction in fruit yields per vine and vegetative growth at the closer within-row spacing than at the closer between-row spacing; this effect of within-row competition was especially pronounced for the vigorous cultivars. Results obtained in this study indicate that increasing the planting density (by reducing the between-row distance) of grapevines on clay loam soils in Ontario may lead to economical increases in production.

Yield and Quality of ‘Niagara’ Grapes as Affected by Pruning Severity, Nodes per Bearing Unit, Training System, and Shoot Positioning

Abstract A 4-year study was conducted on ‘Niagara’ grapes (Vitis labrusca L.) to examine the effects of 3 pruning severities (based on nodes retained), 3 levels of nodes/bearing unit (3, 6, and 9), 2 training systems [Geneva Double Curtain (GDC) and Bilateral Cordon (BC)], and 2 canopy management treatments (shoots positioned and shoots not positioned) on yield and fruit quality. Leaving heavy fruit loads suppressed yields in the 4th and final year of this study as a result of reduced node fruitfulness. The 3 node spurs were not as productive as the 6 and 9 node canes. GDC training produced higher yields than BC training in the 3 high yielding years of the study while maintaining vine vigor. Shoot positioning was more beneficial in increasing yields on the BC training system than on the GDC training system, because of the crowded conditions of the canes on the BC system. The effects of these variables on fruit quality were small, but the heavy fruit loads did result in fruit with a reduced percentage of soluble solids and pH, increased acidity and light color (increased CDM ‘L’ values). Shoot positioning reduced fruit pH, slightly in-creased acidity, and produced darker color (decreased CDM ‘L’ values). Under Arkansas growing conditions, if harvest is delayed beyond 14% soluble solids, it is possible that unacceptable fruit pH and acidity levels will exist.

Black Vine Weevil Control, 1983-84

Abstract Plots, 2 ft x 4 ft, were surrounded by 12-inch-high aluminum barriers. The metal was coated with Fluon to keep the flightless adult weevils from crawling either in or out. Treatments were replicated 4 times in a randomized complete block design and were applied in 1983 on the dates shown in the table. Sprays were applied at the rate of 300 gal of water/acre. Granules were broadcast over the plots by use of a “salt shaker” applicator. Plots were infested with 10 adult black vine weevils on both 1 Jun ’83 and 25 Jun ’83. Sprays were allowed to dry before the weevils were placed on the soil under the vines. Treatments were evaluated on 16 Apr ’84. All vines were pulled from each plot and then vine and root vigor were rated subjectively on a scale of 1 (poorest) to 5 (best). All larvae were collected from the soil and counted.

Principles of Grapevine Canopy Microclimate Manipulation with Implications for Yield and Quality. A Review

This paper develops concepts of grapevine canopy microclimate by considering how the canopy presence can alter the climate. Solar radiation levels are particularly affected due to high absorption by leaves. The radiation environment of canopy exteriors is shown to depend on vineyard geometry and ambient radiation levels. The number of leaf layers within grapevine canopies determines the degree of shading, and an optimal canopy density of about three leaf layers is advocated. Three means of altering canopy microclimate are discussed: shoot number control, vigor control, and use of training systems. The interaction between row spacing, shoot number, vigor, and leaf angle in affecting canopy density is illustrated. Within-canopy shading is promoted by high shoot numbers per hectare, wide row spacing, high vine vigor, and vertical leaves. Examples are given of the effect of reduced vigor on improving canopy microclimate. An analysis of different training systems shows that shading is reduced with narrow rows or by canopy division. The review concludes by considering the effects of canopy microclimate on yield, fruit and wine composition, and offers points for further research.

Impact of Erythroneura comes Say (Homoptera: Cicadellidae) on Caged ‘Concord’ Grapevines 1

Caged ‘Concord’ grapevines were artificially infested with “low” and “high” populations of the leafhopper, Erythroneura comes Say, between early July and late August from 1979 to 1982. Foliage injury became evident shortly after the first introductions and increased during the season. At harvest, the injury inflicted by the “high” populations in the caged vines was similar to or higher than the injury inflicted by natural populations of E. comes in commercial vineyards. The caged grapevines injured by E. comes produced fruit yields and juice quality that did not differ significantly from the noninfested caged vines. In addition, vine vigor was not reduced by the leafhopper injury. Concord vines may be able to withstand greater injury from first- and second-generation E. comes than was previously believed. Lacking in this study was foliage injury that may occur during June from overwintered leafhoppers as they first enter vineyards. This is the main period of berry and cluster primordia initiation, the major contributing factors to fruit production.

The Effect of Source and Rate of Potassium on the Performance of ‘Concord’ Grape Vines Grown on Clay Loam Soils1

Abstract The responses of ‘Concord’ grape vines (Vitis labrusca L.) to 3 potassium fertilizer sources (KCl, K2SO4, and KNO3) used at 2 rates were compared. Fertilizers were applied for 10 years to vines on a poorly drained Jeddo clay loam soil. Performance on a moderately well-drained Oneida clay loam as influenced by KCl and K2SO4 levels was also studied. There was no reduction in yield, fruit quality, or vine vigor with high rates of KCl. KCl and K2SO4 were equally effective in increasing petiole K but the response was slow under Jeddo clay loam conditions. Yield, vigor, and petiole K levels were less with vines receiving KNO3 than with those receiving other sources of K, or with the non-treated control vines. KNO3 was undesirable as a source of K. Petiole K was higher in grape vines growing on Onedia clay loam than on Jeddo clay loam; in addition, they responded more quickly to applied K irrespective of source. There was an indication of a yield response one year to high levels of KCl but no such response occurred with K2SO4. No toxic response to high rates of KCl was detected at either location.

Effects of trellising, crown bunch handling, and the number of oil emulsion and gibberellic acid sprays on harvest-pruned sultanas

Effects of trellising together with the use of various foliage wire arrangements on the production and quality of harvest-pruned sultanas were studied over 4 years. In one experiment a single wire and four narrow 0.4 m 'T' trellis systems, and in a second experiment four 0.9 m wide 'T' trellis and one 0.4 m narrow 'T' trellis system, were tested. Other treatments superimposed on all trellises included crown bunch removal in early spring or at harvest pruning, one and two alkaline oil-in-water sprays (oil sprays) and gibberellic acid (GA) or no GA spray. There were no differences between the four narrow trellises. Dried fruit yield of these four trellises was greater than that of the single wire by an average of 27%, because of higher bunch and cane numbers. There were also no differences between the four wide trellises except that two of the complex ones had more canes. The narrow trellis NTI (used in both experiments) yielded 27% less than the wide trellises because of fewer bunches per vine, caused by lower cane numbers and fruitfulness. Trellising had no effect on fruit quality and only marginal effects on rate of fruit drying, most probably due to low vigour of the experimental vines. As the complex trellis systems had no advantage over the simpler two wire 'T' trellises, their use in harvest pruning is not advocated. In both experiments two oil sprays produced slightly better fruit quality with faster drying of fruit. Use of two oil sprays is warranted where fruit has to be dried rapidly to minimise risk due to rain damage. Early crown bunch removal did not reduce yield and the best time for bunch removal was 6 weeks after bud burst. Use of GA in harvest pruning is not recommended as it does not improve fruit quality and in some years leads to slower fruit drying.

Propagation ofVitis ChampiniPlanchon CV Ramsey. Seasonal and Temperature Effects in Comparison withV. ViniferaL. CV Sultana

The dependence of successful propagation of hardwood cuttings of Ramsey on cane morphology and several environmental factors is examined, and compared with that of Sultana. Successful propagation of Ramsey requires release of organic dormancy and a relatively high culture temperature (c. 25°C). Comparison of Ramsey with Sultana reveals that Ramsey requires longer cold treatment for release of bud dormancy and higher temperatures for root development. The variance of the number of days to root emergence is greater for cuttings selected from light canes than for those selected from heavier, more vigorous canes. This effect is independent of parent vine vigor. With the possible exception of cane weight, none of the morphological characters examined provides a useful measure of predicted cutting performance.

Vine Performance and Wine Quality for Four Red Wine Grape Cultivars Grown for Three Growing Seasons in Erie County, Pennsylvania

Replicated field trials for four red wine grape cultivars (cvs) were initiated in the spring of 1967 at The Pennsylvania State University Field Research Laboratory located in North East, Pennsylvania. The principal objectives were to determine whether cvs other than Catawba and Delaware could be grown commercially in Pennsylvania and produce table wines of acceptable quality exhibiting a "vinifera-like" character. Consistent wine evaluations were made from 1971 through 1973 for these four cvs: Chancellor (Seibel 7053), Chelois (Seibel 10878), DeChaunac (Seibel 9549), and Landot 4511. These trials revealed that at least four cvs can be grown commercially along the southern shore of Lake Erie in Pennsylvania and produce high-quality table wines with a "vinifera-like" character. The cv Chancellor consistently produced a wine of excellent quality. Wines of DeChaunac and Chelois were of high quality, and musts of Landot 4511 fermented into wines of acceptable quality. Average yield of fruit from vines of these four cvs ranged 19.0 metric tons per hectare (t/ha), for Chelois, to 15.3 t/ha, for Landot 4511. Soluble solids of the musts were lowest for DeChaunac (18.5%) and highest for Landot 4511 (19.4%). Total acidity values, expressed as tartaric acid, were lowest for Landot 4511 (0.90 g/100 g of must) and highest for Chancellor (1.13 g/100 g). Average vine vigor for these cvs ranged from 0.6 kg of cane wood per vine (kg/v), for Chancellor, to 1.7 kg/v, for Landot 4511.

Propagation ofVitis ChampiniPlanchon CV Ramsey. Seasonal and Temperature Effects in Comparison withV. ViniferaL. CV Sultana

The dependence of successful propagation of hardwood cuttings of Ramsey on cane morphology and several environmental factors is examined, and compared with that of Sultana. Successful propagation of Ramsey requires release of organic dormancy and a relatively high culture temperature (c. 25°C). Comparison of Ramsey with Sultana reveals that Ramsey requires longer cold treatment for release of bud dormancy and higher temperatures for root development. The variance of the number of days to root emergence is greater for cuttings selected from light canes than for those selected from heavier, more vigorous canes. This effect is independent of parent vine vigor. With the possible exception of cane weight, none of the morphological characters examined provides a useful measure of predicted cutting performance.

SOME CLUSTER THINNING AND GIBBERELLIC ACID EFFECTS ON JUICE AND WINE QUALITY OF DE CHAUNAC GRAPES

Thinning to one and two flower clusters per fruitful shoot significantly increased total soluble solids and total phenols but had no effect on titratable acidity of de Chaunac grapes in two vineyards differing widely in vine vigor and soil type. Treatment with 50 ppm gibberellic acid 10 days after bloom did not affect juice quality at either location. Grapes from the high vigor, heavy soil site were particularly high in titratable acidity, and potassium content was higher in berries from thinned vines in the same vineyard. An early assessment of wine quality showed the one-cluster treatment to be superior.

Cluster-thinning ‘de Chaunac’ French Hybrid Grapes Improves Vine Vigor and Fruit Quality in Ontario1

Abstract Cluster-thinning of the French hybrid grape cultivar ‘de Chaunac’ (Vitis sp.) resulted in superior fruit quality and an increase in vigor of the vines in comparison to the unthinned vines in a similar pruning and management regime. The higher sugar levels associated with thinning are consistently desirable for wine making under Ontario conditions. The favorable test site used limited the expression of vine decline and winter injury usually associated with over-cropping of this cultivar in the Niagara Peninsula of Ontario.

Evaluating Drip, Flood, and Sprinkler Irrigation of Wine Grapes

The response of Saint Emilion to drip, flood, and sprinkler irrigation was measured in the southern San Joaquin Valley. The trial began in 1972 after planting, and the extent of plant and soil modifications was monitored through 1974. The principal benefit with drip irrigation was increased efficiency of water use. Drip irrigation used less water while maintaining vine vigor, fruit production, and fruit quality similar to results with sprinkler or flood irrigation. Soil salt levels with sprinkling and flooding were similar but lower than observed with drip irrigation. With drip irrigation, total salts and sodium concentrated on the surface 100 cm from the vine row (drip line) and to a 30-cm depth. Soil-water pressure-head values and hydraulic gradients indicated substantial soil-water flow to the 150-cm depth following both flood and sprinkler irrigation, whereas flow to the 150-cm depth was slight with drip irrigation.

Evaluating Drip, Flood, and Sprinkler Irrigation of Wine Grapes

The response of Saint Emilion to drip, flood, and sprinkler irrigation was measured in the southern San Joaquin Valley. The trial began in 1972 after planting, and the extent of plant and soil modifications was monitored through 1974. The principal benefit with drip irrigation was increased efficiency of water use. Drip irrigation used less water while maintaining vine vigor, fruit production, and fruit quality similar to results with sprinkler or flood irrigation. Soil salt levels with sprinkling and flooding were similar but lower than observed with drip irrigation. With drip irrigation, total salts and sodium concentrated on the surface 100 cm from the vine row (drip line) and to a 30-cm depth. Soil-water pressure-head values and hydraulic gradients indicated substantial soil-water flow to the 150-cm depth following both flood and sprinkler irrigation, whereas flow to the 150-cm depth was slight with drip irrigation.

Responses of Mature Concord Grapevines to SADH in Pennsylvania1

Abstract Applications of succinic acid-2,2-dimethylhydrazide (SADH) solutions at 125, 250, 500 and 1000 ppm during the 1967-1969 growing seasons in Erie County, Pennsylvania were not effective in increasing yields of mature ‘Concord’ grapes (Vitis labrusca L.), although the number of berries per basal cluster and cluster weights were increased significantly over the three-year experimental period. Berry weights and vine vigor were reduced significantly at the highest concentration of SADH utilized in this study. Treatments did not significantly affect the amount of fruit produced per node retained or juice quality.

Effect of Pruning Severity and Rootstock on Growth and Yield of Two Grafted, Cane-pruned Wine Grape Cultivars1

Abstract Three years of observations were made at Oakville, California, on a vineyard trial of 3 pruning severities on 2 scion grape cultivars, Chardonnay and Gamay Beaujolais, grafted onto 2 phylloxera-resistant rootstocks, ‘St. George’ and ‘A × R #1’. There was a marked increase in crop production with decreased pruning severity. With ‘Chardonnay’ on ‘St. George’ there was nearly a 3-fold increase in yield when the pruning went from 5 retained buds/lb. (453.6g) of prunings to 15 buds/lb. With ‘Gamay Beaujolais’, the yield increase approached 2-fold. Vines on ‘A × R #1’ were markedly more fruitful than those on ‘St. George’, and this rootstock difference was not influenced by pruning severity over a 3-year period. The variability in level of pruning, as estimated from a visual inspection of individual vines, was great. This could account for both low yields and high vine sizes with ‘Chardonnay’. The pruning level used by an experienced pruner was about 8 retained buds/lb. of prunings on average-sized vines of ‘Chardonnay’ on ‘St. George’, and about 6 buds on the largest vines. The most severe pruning was very restrictive on yields per vine, and vine vigor was enhanced at these low bud counts. Fruit maturity was delayed by the least-severe pruning level and, in some instances, vine size was reduced the following year. Under the conditions of the test site, the intermediate level of pruning severity, 10 buds/lb. of prunings, was appropriate for the small-clustered, cane-pruned cultivars at the intermediate vine sizes.

Effect of Ethephon and A Morphactin on Growth and Fruiting of 'Thompson Seedless' and 'Carignane' Grapes

Ethephon [(2-chloroethyl) phosphonic acid] and a morphactin IT 3456 (methyl-2-chloro-9-hydroxy-fluorene-9-carboxylate) were applied as sprays to 9Thompson Seedless9 and 9Carignane9 grapes at prebloom, bloom, fruit set, or 2 weeks after fruit set. Ethephon was used at 30, 300, and 3,000 ppm, and morphactin at 0.1, 1, 10, and 100 ppm. On 9Thompson Seedless,9 morphactin at 100 ppm resulted in much leaf cupping and abnormal venation. Prebloom and bloom treatments had more formative effects than did later applications. However, axillary bud growth was stimulated by sprays at fruit set and after fruit set. The response of 9Carignane9 was similar but less marked. Ethephon at 3,000 ppm applied at prebloom or bloom to 9Thompson Seedless9 caused curling of shoot tips and development of abscission layers at the apical nodes. Ethephon reduced the crop on 9Thompson Seedless9 at almost every level tested, and 30 ppm was effective at the prebloom stage. With 9Carignane9, fruit set was reduced by all concentrations of ethephon except with the treatment after fruit set. Morphactin reduced the crop of 9Thompson Seedless9 the most when applied at prebloom or fruit set, and 9Carignane9 was most sensitive at the first three growth stages. In the season following treatment, bud break was usually delayed on 9Thompson Seedless9 that had been treated with ethephon; but morphactin delayed bud break only when 100 ppm was applied at prebloom. Both ethephon and morphactin applied at the high rate usually reduced the number of clusters the following year. Growth of ethephontreated 9Thompson Seedless9 vines was weak, especially with the higher concentration. Results with 9Carignane9 were similar to those of 9Thompson 9Seedless9. Main veins of the leaves and clusters of 9Carignane9 treated with morphactin were fasciated, though vine vigor was normal. With later dates of treatment, damage on leaves and clusters was closer to the apex.

Changes in soil chemical properties in a long-term fertilizer trial in a non-irrigated vineyard

Changes in soil properties in a long-term factorial experiment with nitrogen, phosphorus, and potassium fertilizer at the Nuriootpa Viticultural Research Station in South Australia were measured after 23 years of application. The measurements were related to vine yield responses reported earlier. Phosphorus, broadcast as superphosphate, gave excessively high available phosphorus levels in the top 6 in, of soil, but yield responses were delayed for 8 years until the slow-moving phosphorus reached the 6–12 in. layer where the feeder roots occurred. Broadcasting superphosphate was a wasteful and inefficient means of applying phosphorus in this environment. About three-quarters of the phosphorus applied could be measured in the top foot of soil. Nitrogen applied as sulphate of ammonia reduced pH significantly in the top 18 in. of soil, with the biggest reduction of 1.5 units to pH 5.0 in the 6–12 in. layer. As this acidity developed it probably caused the depression in vine vigour and yield. Potassium levels were high and not limiting in the unfertilized soils. The relation between nutrients supplied in the fertilizers and nutrients removed in the grapes is discussed.

Phosphorus Fertilization of Hops1

AbstractHops were grown on field plots treated with five levels of phosphorus fertilization to determine the effect of P on vine growth, cone quality, and zinc nutrition. A maximum P treatment of 1,344 kg/ha, applied over a 5‐year period, increased the extractable P level of the surface 20 cm of soil from 10 ppm to approximately 100 ppm. The P level in leaves and cones from this treatment was increased by approximately 0.10 to 0.15% P as compared with the no‐P treatment. Increased levels of P had no observable effect on vine color and vigor or on total growth as determined by vine green weight. The critical level for P in sidearm leaves at early bloom was indicated to be below 0.25%.The alpha acid content of cones decreased where P fertilization exceeded approximately 500 kg/ha. However, this decrease was poorly correlated with the P content of leaves, indicating the lack of a direct causal relationship.The P treatments caused a definite reduction in the Zn concentration in leaf and cone tissues, but did not induce observable Zn deficiency symptoms.

The effect of some Cultural Practices on Nitrogen and Fruitfulness in the Sultana Vine

In a small field trial over two seasons, sowing a cereal crop between the rows of Sultana vines at the beginning of September, and turning it in in late November a few days after full flowering for the vines, led to reduced leaf nitrogen in the vines over the period of differentiation of inflorescence primordia. In the second season there was a 27% increase in bunches per vine on such vines, compared with vines treated according to good district practice and already yielding more than district average. Since there was no sign of moisture stress due to the cereal, and no reduction in berry set, which is known to be affected by moisture stress, the increase in bunch number is associated with reduced nitrogen, but the treatment caused weakening of some of the vines and reduced yield in the following year and was discontinued. Further attempts to lower soil nitrogen enough to increase number without seriously affecting vine vigor have not succeeded.