Vine Nutrient Status Research Articles

Phenological Stage and Tissue Type of Grapevines Affect Concentrations and Variability of Mineral Nutrients

<h3>Abstract</h3> <h3>Background and goals</h3> There is currently no consensus on the ideal tissue type or on the ideal phenological stage at which to sample grapevine mineral nutrients. The goal of this study was to assess the concentrations and variability of nutrients in leaf blades and petioles during differing phenological stages and in different vineyards. <h3>Methods and key findings</h3> The study was conducted in the Finger Lakes region of New York State. Multivariate analysis showed that phenology, tissue type, vineyard site, and year all influence vine nutrient status. Tissue type accounted for more than twice the proportion of variance within the model than site, even though these vineyards consisted of different soil types, ages, rootstocks, and training systems. Within tissue type, leaf blade samples had lower variability than petioles; petiole samples had 30% greater variability in nutrient concentrations than leaf blades. Tissue samples taken at bloom had 66% greater variability than those sampled at veraison. <h3>Conclusions and significance</h3> The differences in nutrient concentrations among different tissue types and phenological time points underscore the importance of basing recommended nutrient concentrations on specific tissue types and time points. We concluded that nutrient recommendations should be developed based on leaf blade samples to assess vine nutrient status more precisely. Sampling tissue at veraison provided samples with lower variability. However, logistical considerations such as obtaining grapevine nutrient reports with sufficient time to address deficiencies within the current growing season, may be of greater importance to growers. The results within this study may be region- and/or cultivar-specific.

Phenological Stage and Tissue Type of Grapevines Affect Concentrations and Variability of Mineral Nutrients

<h3>Background and goals</h3> There is currently no consensus on the ideal tissue type or on the ideal phenological stage at which to sample grapevine mineral nutrients. The goal of this study was to assess the concentrations and variability of nutrients leaf blades and petioles during differing phenological stages and in different vineyards. <h3>Methods and key findings</h3> The study was conducted in the Finger Lakes region of New York State. Multivariate analysis showed that phenology, tissue type, vineyard site and year all influence vine nutrient status. Tissue type accounted for more than twice the proportion of variance within the model than site, even though these vineyards consisted of different soil types, ages, rootstocks and training systems. Within tissue type, leaf blade samples had lower variability than petioles; petiole samples had 30% greater variability in nutrient concentrations than leaf blades. Tissue samples taken at bloom had 66% greater variability than those sampled at veraison. <h3>Conclusions and significance</h3> The differences in nutrient concentrations among different tissue types and phenological timepoints underscore the importance of basing recommended nutrient concentrations on specific tissue types and timepoints. We concluded that nutrient recommendations should be developed based on leaf blade samples to more precisely assess vine nutrient status. Sampling tissue at veraison provided samples with lower variability. However, logistical considerations, such as obtaining grapevine nutrient reports with sufficient time to address deficiencies within the current growing season, may be of greater importance to growers. The results within this study may be region and/or cultivar specific.

Cover crops and a devigorating rootstock can impart substantial agroecosystem services to high-resource vineyards: A multi-year study

In vineyards, cover crops typically grow concurrently with grapevines and can impart a multitude of agroecosystem services; yet concerns over potential disservices might limit adoption. Reductions in yield and vegetative growth are key disservices of concern, but at sites with high soil resources, reducing excessive vegetative growth is often considered beneficial, if the yield is not strongly penalized. To optimize agroecosystem services provided by cover crops, it is crucial to examine above- and belowground plant responses over multiple years. Documentation of the responses of fruit crop root systems to cover crops may clarify potential benefits for long-term agroecosystem services associated with aboveground growth and soil resources. In 2016, we established a perennial grass under young vines (full floor cover) to examine if agroecosystem services imparted by an under-vine cover crop change in the first five years of vineyard production and depend on rootstock vigor. Overall, cover crop reduced grapevine vegetative growth between 13% and 30% across all years and with a trend of more substantial reductions in the first two years. In contrast, yield was reduced in only three of the five years, between 9% and 25%, depending on the rootstock. Furthermore, neither cover crop nor differences in rootstock vigor resulted in relevant or consistent changes in fruit chemistry during the study. Overall, we found that in a relatively fertile, young vineyard, combining a lower vigor rootstock with a perennial, under-vine cover crop imparts substantial agroecosystem services in comparison to the more common practices of using a medium vigor rootstock and spraying herbicide under the vines. These services included improved crop load (ratio of fruit to vegetative mass), increased soil phosphorus availability, increased deep soil water content, and presumably lower labor and other costs associated with vineyard maintenance. Studies on a decadal timescale are needed to further clarify whether these services persist, accumulate with time, or if competition from the cover crop eventually leads to unacceptable decreases in vine nutrient status, growth, and production.

Tolerance of Muscadine grapes (&lt;i&gt;Vitis rotundifolia&lt;/i&gt;) to alkaline soil

Muscadine (Muscadinia rotundifolia) grapes have been used in grape variety and rootstock development due to their inherent pest and disease resistance, but little is known about their alkaline soil tolerance. In this study, Muscadine varieties, commercialrootstock and interspecific hybrid grape (Vitis spp.) cultivars were evaluated for alkaline soil tolerance under field conditions to determine the potential suitability of muscadines for rootstock development. Thirty-one muscadine and eleven interspecific hybridgrape cultivars were grown in a moderately alkaline soil (pH = 8.1) over a three-year period. Alkaline soil tolerance wasdetermined by relative vine vigour (shoot length), vine nutrient status (whole leaf tissue testing) and visual chlorosis. Additional data were collected on the timing of budbreak. Overall, the muscadines studied expressed low vigour and had greater chlorosissymptoms than the interspecific hybrid rootstocks (Paulsen 1103, Millardet et de Grasset 101-14, Millardet et de Grasset 420A,Ruggeri 140, Schwarzmann, and Matador). These parameters were not correlated with the concentration in any specific nutrient, although nutrient deficiencies (nitrogen, copper) and excesses (calcium, boron) were observed in the muscadine varieties.Overall, the muscadine grapes expressed poor alkaline soil tolerance compared to interspecific hybrid grape rootstocks (1103P, 101-14 MGt., 140Ru, Schwarzmann, 420A, and Matador), even the ones having poor alkaline soil tolerance (101-14 MGt., Schwarzmann) and own-rooted cultivars (Black Spanish, Blanc Du Bois, Dunstan’s Dream and Victoria Red). Nevertheless, some variability in chlorosis symptoms and nutrition was observed across the muscadine group, suggesting some interests to select Muscadine hybrid rootstocks less sensitive to iron chlorosis.

Compost Application to Degraded Vineyard Soils: Effect on Soil Chemistry, Fertility, and Vine Performance

A two-year experiment investigated the effects of compost application rate on soil chemical properties, vine nutrient status, vine performance, and grape juice characteristics in a degraded vineyard soil in northern California. The intent of the research was to identify vineyard management strategies to improve soil fertility and to identify optimal compost application rates. We applied composted steer manure at three rates (11.2, 22.4, and 33.6 t/ha) in a randomized complete block design before the 2012 growing season. Pruning and berry weight increased over the control at the highest application rate in both years, while vine yield significantly increased over the control in year two. Polynomial orthogonal contrasts suggest that pruning weight, vine yield, and berry weight increased linearly with increasing compost application rate in 2012, and that vine yield and berry weight increased linearly and quadratically with compost application rate in 2013. Measured soil properties increased from compost application, including nitrogen (N), carbon, pH, exchangeable potassium (K), manganese, and calcium and available phosphorus (P, Olsen-P), while phosphorus fixation decreased. Vine petiole nutrients (N, P, and K) significantly increased from compost application in both years. Juice characteristics (pH, total soluble solids, and titratable acidity) were unaffected by compost application. Similarly, vine balance was unaffected by compost application. All vine metrics improved at the highest application rate, and soil chemical properties increased with the two highest application rates. Therefore, significant benefits to soil fertility and vine performance can be achieved for at least two years in degraded vineyard soils following a single dose of compost at higher application rates (22.4 and 33.6 t/ha) without compromising juice characteristics or vine balance.

Utility of dormant season pruning wood to predict nutrient status of grapevines

Grape growers utilize leaf blades or petioles collected during the growing season to monitor vine nutrition. However, an earlier indicator of vine nutrient status is desirable. The pruning wood derived from last season’s fruiting shoots (dormant stems) collected in winter may be a useful tissue to assess vine nutrition before the growing season. The utility of dormant stems to indicate grapevine nitrogen (N), phosphorus (P), and potassium (K) status was tested in Pinot noir grapevines (Vitis vinifera L.) from a microplot vineyard where varying levels of N, P, or K were provided over four years. Dormant stem nutrients were evaluated based on their response to varying nutrient supply and as predictors of vine nutrient status in the upcoming growing season. Concentrations of P and K in dormant stems reflected the amount of P and K supplied to vines, and effects grew larger over time. The concentrations of P and K in dormant stems also correlated well with next season P and K levels in leaf blades and petioles. Relationships between leaf blade and petiole tests and dormant stems were more consistent across three years for P than for K. Nitrogen concentrations in dormant stems did not consistently reflect N inputs and were correlated only weakly to leaf blade and petiole N tests during the growing season. These findings indicate that dormant stems can be useful for diagnosing P and K status of grapevines.

Potassium Requirements for Pinot noir Grapevines

The potassium (K) requirements of Pinot noir grapevines were studied in a microplot vineyard, where four levels of fertilizer K supply were carefully controlled. Vine nutrient status, productivity, and must chemistry were studied over four years, and fermentation dynamics were evaluated over three years. Vine productivity, based on leaf area, pruning weights, and yield, was reduced by K supply only after four years in vines receiving no K fertilizer. K deficiency symptoms were apparent on leaves and fruit in vines receiving no K the year before productivity was altered, and after must pH was already reduced. Must pH was reduced below the level of control (100% K) vines in year 2, and thereafter in vines receiving no K, and also in years 3 and 4 in vines receiving 20% K. Late bunch stem necrosis occurred on some fruit clusters in year 3 in vines receiving no K and 20% K; this increased dramatically in year 4 in the no-K vines. Low must pH values of ~3.0 and must K concentrations as low as 600 mg K/L did not influence the rate of alcoholic fermentation. These findings indicate that monitoring must pH in addition to leaf blade or petiole K concentrations would be helpful in managing vine K status. A leaf blade K level of 6.0 g K/kg dry weight (DW) at veraison is proposed as the critical concentration for Pinot noir vines cropped at levels typical for the region. Growers should monitor vine K status closely and must pH when leaf blade K at veraison approaches 7.0 g K/kg DW in western Oregon Pinot noir vineyards to account for sampling and laboratory error.

Sensory attributes of wines made from vines of differing phosphorus status

Aim: The implications of water and nutrient deficiencies for photosynthesis, dry matter production, and yield have been well documented. However, whereas multiple studies show that water deficits affect grape and wine quality as well as wine sensory characteristics, the corresponding implications of manipulating vine nutrient status through fertilizer additions remain largely unexplored.Methods and results: In this study, phosphorus (P) fertilizers were applied to P-deficient vineyards of Cabernet Sauvignon, Chardonnay, and Chenin blanc growing in rhyolite, granite, and schist derived soils. Bloomtime leaf lamina P levels, basic soil chemical characteristics, juice P, and wine chemical parameters were measured after harvest. A highly sensitive protocol for sensory evaluation was used to test the wines made from the treated and untreated grapes for differences in wine appearance, flavor, aroma, and taste.&#x0D; All P additions were effective in rapidly increasing both vine P status and P in the harvested juice. In Cabernet Sauvignon vines growing on rhyolite, juice P was linearly related to vine P status compared to a non-linear accumulation of juice P in Chenin blanc vines growing on an calcium-rich schist soil. Soil CEC and Ca levels were both higher in the schist derived soil than in the rhyolite or granite soils, indicating a possible association of P release with soil parent material. Differences were detected in appearance, flavor, aroma, and taste in wines made from all three varieties on all three sites. Also, increasing vine P status increased the concentration of anthocyanins and soluble phenolics in the wines, and reduced fermentation time in the Cabernet Sauvignon.Conclusions: The results of this study show that vine P nutrient status can be manipulated by the grower across different soil types. Vine nutrient status has also been shown to significantly affect vine bud fertility, photosynthesis, dry matter and fruit production, and grape and wine chemical parameters. However, there is a lack of data describing the effect of manipulating vine nutrient status through fertilizer additions on the resulting wine sensory profile. Our results show that vine P status can influence the sensory attributes of wines.Significance and impact of the study: The results of this study and earlier work with vine water status identify two vineyard sources of variation in wine sensory attributes that occur both naturally and can be manipulated by the grower across different soil types.

Defining Phosphorus Requirements for Pinot noir Grapevines

A study to examine the phosphorus (P) requirements of Pinot noir was carried out using a microplot vineyard with carefully controlled P inputs. Pinot noir grafted onto 101-14 rootstock was exposed to four levels of P supply delivered via fertigation beginning in their fourth growing season. Vine nutrient status, productivity, and must chemistry were studied over four years (2012 to 2015), and fermentation dynamics were evaluated over three years (2012 to 2014). P supply primarily influenced vine productivity by reducing leaf area at veraison and by reducing yield, which occurred after three years in vines that received no P fertilizer. Flowering and fruit set were not altered by low P status. P supply had the most significant impact on must P levels, where the two lowest P supply treatments had reduced must P within the first year that P was altered. However, must P concentrations as low as 32 mg P/L did not affect the time needed for yeast to complete alcoholic fermentation. These findings suggest that limiting P reduces Pinot noir canopy size and yield before it alters flowering parameters or reduces must P concentrations sufficiently to alter fermentation. A P concentration of 1.0 g P/kg dry weight (DW) in leaf blades at veraison is proposed as the critical level below which growth and yield of Pinot noir are reduced when vines are cropped at levels typical for premium wine production in the region. Growers should closely monitor vine P status when leaf blade P at veraison approaches 1.2 g P/kg DW in western Oregon Pinot noir vineyards to account for sampling and laboratory error.

N, P, and K Supply to Pinot noir Grapevines: Impact on Vine Nutrient Status, Growth, Physiology, and Yield

Pinot noir grapevines (self-rooted Pommard clone) were grown in a pot-in-pot sand culture vineyard to examine the impact of low N, P, and K supply on vine growth and physiology. Four-year-old vines were given either full nutrition (Control) or reduced levels of each N, P, and K supplied at 50%, 20%, or 10% of the Control rate with all other nutrients held constant over three years (2006–2008). Vine growth, nutrient status, photosynthetic parameters, yield, and berry quality were monitored. The N, P, and K status of vines was reduced by each of the intended treatments, although N and P concentrations in leaf blades and petioles were reduced earlier and to a greater extent than K. Low N treatments reduced dormant season cane weights in all years, shoot lengths and leaf area in 2008, and fruit yield in 2008. Yield reduction under low N supply in 2008 was primarily a result of reduced berry size. Low N also reduced single leaf photosynthesis and quantum efficiency of photosystem II in 2008, while low P and K did not. Juice YAN (yeast assimilable nitrogen) levels were greatly reduced by low N supply in 2007 and 2008, although YAN was lower in 2007 across all treatments. Low P and low K supply did not alter growth or yield. Low P supply reduced juice P concentrations, but low K supply did not alter juice K. Reduced yield, growth, and juice YAN levels in low N treatments provide a framework to refine leaf blade and petiole N standards for Pinot noir grown in the region, but limiting levels of P and K were not as clearly defined.

The diversity of arbuscular mycorrhizal fungi amplified from grapevine roots (Vitis vinifera L.) in Oregon vineyards is seasonally stable and influenced by soil and vine age

The diversity of arbuscular mycorrhizal fungi (AMF) in 10 Oregon vineyards was assessed by examining spores in soil and amplifying mycorrhizal DNA from roots. Seventeen spore morphotypes were found in soil, including seven species in the Acaulosporaceae. Eighteen phylotypes were amplified from grape roots with AM1 and NS31 primers, and clones were dominated by Glomus spp. (> 99%). A few clones (< 1%) representing a single phylotype within Gigasporaceae, and a single clone within Archaeosporaceae were amplified from roots with AM1-NS31 primers. A separate experiment employing known proportions of grape roots colonized by Glomus intraradices or by Gigaspora rosea showed that fungi within Gigasporaceae might be underrepresented in clone abundance when Glomus spp. co-occur in roots. No clones representing fungi within the Acaulosporaceae were amplified from vineyards, although specific fungi within Acaulosporaceae were shown to colonize Pinot noir roots in sterilized soil and were amplified from these roots. Four Glomus phylotypes, including G. intraradices, were found in roots from all 10 vineyards, and these fungi accounted for 81% of clones. AMF phylotypes amplified from roots did not change during the growing season, although six phylotypes varied with soil type. The presence of three phylotypes was affected by vineyard age, and phylotype richness appeared to decline as vineyard age increased beyond 20 y. PCA analysis supported the hypothesis that the AMF community is different in red-hill soils than in valley soils and indicated certain phylotypes might be associated with lower soil and vine nutrient status. However, the changes in the AMF community in grape roots across vineyards were subtle because most root samples were dominated by the same three or four phylotypes. A separate analysis using primers to amplify AMF from the Archeasporaceae/Paraglomeraceae showed most root samples also were colonized by at least one Paraglomus or Archaeospora phylotype.

Influence of Geotextile Mulches on Canopy Microclimate, Yield, and Fruit Composition of Cabernet franc

Three vineyard floor management strategies—reflective (white) geotextile mulch, black geotextile mulch, and an herbicide strip in vine rows—were evaluated with regard to canopy light and temperature, vine growth, and fruit composition of Cabernet franc. Using a randomized complete block design, two trials were conducted at commercial vineyards in the Finger Lakes Region of New York during 2004 to 2005. Black and white geotextiles in 2-m-wide or 5-m-wide strips almost doubled vine size after two years, but did not affect overwinter primary bud survival compared with mowed sod row middles with undervine herbicide control treatment. In both experiments, the white geotextile mulch significantly increased sunlight reflected from the vineyard floor into the vine cluster zone, especially early in the growing season. Vines mulched with white geotextile had greater yields, but there were no significant differences in fruit ripening time or fruit chemical composition at harvest, and minimal differences in vine nutrient status among the floor management systems. The increased yield values in reflective geotextile plots were not sufficient to compensate for the substantially greater costs of geotextiles relative to the standard practices of mowed sod row middles with undervine herbicide weed control.

The effect of recycled water on the nutrient status of Soultanina grapevines grafted on different rootstocks

The effects of municipal reclaimed effluent on the nutrient status of potted Soultanina grapevines grafted on three rootstocks (41B, 1103P and 110R) and irrigated at various fractions of evapotranspiration (0.50, 0.75 and 1.00) were investigated for a 3-year period. Vines irrigated with recycled water had a lower leaf-N content, which reached deficient levels early in the 1999 season. With regard to the other nutrients (P 3+, K +, Mg 2+ and Fe 3+), the findings in this study show that effluent was capable of supplying vines with sufficient quantities of all of them. Enhanced levels of Zn 2+ and Cu 2+ were also found in the leaves of vines irrigated with recycled water, but their content remained within the acceptable range suggested for grapevines. The irrigation level strongly affected leaf-K + status, but only minor effects were found for the other elements. Rootstock had a major effect on leaf nutrient content. Significant interactions between rootstock and water quality reveal that the effect of rootstock on vine nutrient status was also affected by the availability of nutrients. Vines grafted on 41B showed a greater capacity to maintain leaf nutrient content, irrespective of nutrient availability, than those grafted on 1103P and 110R.

Preparation and Analysis of Grape Leaf and Petiole Samples by NIR Spectroscopy

NIR-based tissue analysis has proven useful in Australia for making fertilizer recommendations for rice and wheat growers. Viticulturists have for some time made fertilizer recommendations based on tissue analysis, although there is some debate in the literature as to whether younger or older leaves or petioles provide the best indicator of vine nutrient status for diagnostic purposes. The aim of our research has been to develop NIR-based nutrient analysis for grape producers. Aspects of sample collection, including leaf lamina vs. leaf petiole; leaf opposite the basal cluster vs. youngest leaf; aspects of drying (microwave vs. convection oven), have been reexamined from the viewpoint of convenience, cost, accuracy, and turnaround time with respect to NIR analysis. We have refined procedures for collecting and microwave-drying samples. The samples of leaves and petioles were collected from vines in most wine-growing regions of Australia and included all the major wine grape and some dried fruit cultivars on their own and, in some cases, on rootstocks. At this stage, we have developed preliminary NIR calibrations for the major nutrient elements in both leaf lamina and petioles.

Preparation and Analysis of Grape Leaf and Petiole Samples by NIR Spectroscopy

NIR-based tissue analysis has proven useful in Australia for making fertilizer recommendations for rice and wheat growers. Viticulturists have for some time made fertilizer recommendations based on tissue analysis, although there is some debate in the literature as to whether younger or older leaves or petioles provide the best indicator of vine nutrient status for diagnostic purposes. The aim of our research has been to develop NIR-based nutrient analysis for grape producers. Aspects of sample collection, including leaf lamina vs. leaf petiole; leaf opposite the basal cluster vs. youngest leaf; aspects of drying (microwave vs. convection oven), have been reexamined from the viewpoint of convenience, cost, accuracy, and turnaround time with respect to NIR analysis. We have refined procedures for collecting and microwave-drying samples. The samples of leaves and petioles were collected from vines in most wine-growing regions of Australia and included all the major wine grape and some dried fruit cultivars on their own and, in some cases, on rootstocks. At this stage, we have developed preliminary NIR calibrations for the major nutrient elements in both leaf lamina and petioles.