Enrique García-Escudero

Effects of Leaf Position on Blade and Petiole Mineral Nutrient Concentration of Tempranillo Grapevine (Vitis vinifera L.)

Concentrations of N, P, K, Ca, Mg, Fe, Mn, Zn, Cu, and B were monitored throughout the season in leaf blades and petioles sampled at three different positions on the shoot of Tempranillo (Vitis vinifera L.) grapevines. Petioles had higher concentrations of K, Mg, and Zn, whereas N, P, Ca, and micronutrients other than Zn were more abundant in leaf blades. Seasonal trends were identified for macronutrients, with decreasing patterns for N, P, and K, while Ca and Mg increased through the season. Minor differences in nutrient concentration were observed in leaf blades and petioles opposite basal and distal clusters. These results provide guidelines for the sampling of representative tissues for nutritional diagnosis of Tempranillo after veraison. However, differences among leaves opposite basal clusters and those placed four nodes beyond the second cluster suggest that these younger leaves are not useful for nutritional diagnosis using reference concentrations obtained for basal leaves.

Cover crops and tillage influence soil organic matter and nitrogen availability in a semi-arid vineyard

Little attention has been given to the utilization of permanent cover crops in vineyard agroecosystems in semi-arid Mediterranean climatic conditions to increase soil organic carbon or its effects on N availability. We evaluated the effect of permanent cover crops with resident vegetation on labile organic matter fractions and inorganic N availability with respect to conventional tillage in a semi-arid vineyard. The field experiment was conducted on Typic Haploxerept soil, located in La Rioja area (Central River Ebro Valley). Soil samples were collected during June 2009, 5 years after covers crops were established. Soil organic carbon (SOC), water-soluble carbon (WSC), potentially mineralizable nitrogen (PMN), nitrate (N-NO3 −) and ammonium (N-NH4 +) were measured. At soil depths of 0–2.5 and 2.5–5 cm the cover crops increased SOC, WSC and PMN. So the results indicated a soil quality improvement. The cover crop treatment reduced soil N-NO3 − and increased the WSC to inorganic N ratio at 0–45 cm depth. PMN and WSC increments suggest a more active microbial biomass that could promote the immobilization and recycling of N-NO3 −, and therefore might partially explain the reduction in N-NO3 − pools under cover crops.

Reference Levels for Leaf Nutrient Diagnosis of cv. Tempranillo Grapevine in the Rioja Appellation

Plant nutritional diagnosis requires specific reference levels for each variety to effectively reflect the nutritional status of the crop. A vine nutritional survey was undertaken in the Rioja A.O.C., northeastern Spain. The survey method was used to establish the preliminary reference levels for the nutritional diagnosis of leaf blade and petiole tissues of Vitis vinifera L., cv. Tempranillo on Richter-110 rootstock. These references were generated from data obtained during the course of 11 years (2000–10) from 166 vineyards trained on Gobelet and Vertical Shoot Position (VSP), pruned in Guyot or Double Cordon Royat, systems. The database obtained included information from different altitudes, soil types, cultural practices, and climatic conditions within the Rioja appellation. The majority of the vineyards had no irrigation and soil was tilled mechanically. Nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), and boron (B) were analyzed in leaf blade and petiole dry tissues sampled at both flowering and veraison. Vineyards with phytosanitary damages, flowering problems, and data with extreme nutrient values were discarded. Data were statistically analyzed to obtain the normal average values considering the (μ ± 0.25σ) of the central data as optimal levels and the tails values (μ ± 0.84σ) of the population as excessive or deficient levels. The statistical procedure included the Kolmogorov–Smirnov nonparametric test for normality, data transformations for normality, and the calculation of percentiles when those transformations to normal distributions become unlikely (P20, P40, P60, and P80). Finally, reference levels for leaf blade and petiole at both flowering and veraison are proposed for the nutrition diagnosis of the cv. Tempranillo grapevine in the Rioja A.O.C.

Soil nutrient availability under Cover Crops: Effects on vines, must, and wine in a Tempranillo Vineyard

Cover crops can compete with vines for soil nutrients and thus can affect grapevine development and must and wine quality. The objective of this study was to evaluate the influence of two different cover crops on the availability of soil N, P, K, and Mg and on grapevine nutritional status, vigor, yield, and must and wine quality. The experiment was carried out in a cv. Tempranillo vineyard in La Rioja, Spain, using three treatments: a gramineous cover crop (barley), a leguminous cover crop (clover), and conventional tillage. Soil nitrate evolution and P, K, and Mg were determined, and total biomass and nutrient content of cover crops were measured. We also assessed leaf nutrient content, vine vigor, yield, and must and wine quality. Uptake of P, K, and Mg by cover crops did not reduce the soil availability of those nutrients and did not affect their concentrations in grapevines. The barley cover crop reduced soil N availability from the first year onward and led to decreased leaf N and vine vigor in the third year. Increased polyphenol content and color intensity were observed in the barley treatment in the fourth year, and these changes were more significant in must than in wine. The clover treatment increased soil N availability in years 2 through 4 and led to increased leaf N content in the third and fourth years. The use of barley as a cover crop could be a viable alternative for reducing soil N and improving must and wine quality; however, these effects required time to develop after introduction of the cover crop.

Cover Crop Short-Term Effects on Soil NO3 --N Availability, Nitrogen Nutritional Status, Yield, and Must Quality in a Calcareous Vineyard of the AOC Rioja, Spain

Cover crop use in vineyards can affect both vine vigor and must and wine quality because of the competition for soil nutrients and water. Our objective was to study the short-term effects of a cover crop on the nitrate (NO3 −)–nitrogen (N) availability throughout the grapevine vegetative cycle, the grapevine and cover crop N uptake, and the yield and must quality. By short-term effects we mean the first crop cycle after planting the cover crop. The experiment was set in 2009 on a cv. Tempranillo vineyard planted in a Oxyaquic Xerorthent soil. The soil had not been fertilized with N since 2000, and two types of soil management were studied: (1) conventional tillage (CT) and (2) barley (Hordeum vulgare L.) cover crop (B). Soil samples were taken in March (bud break), June (bloom), July (setting), and August (veraison) of 2009, and the extractable NO3 −-N was determined. At bloom and veraison, N contents in both blade and petiole were determined. At bloom the grapevine N uptake was estimated using the aerial parts (leaves, shoots, and bunches), and for the cover crop N uptake was determined. Total yield, bunch, and shoot weight as well as must anthocyanin and polyphenol contents were determined. Soil NO3 −-N availability decreased in the cover crop from June until August, with the reduction being similar to the cover crop N uptake. Also N contents in both petiole and blade decreased in the cover crop at veraison. Regarding must quality, the cover crop increased the anthocyanin content. The reduction of soil NO3 −-N availability throughout the vegetative cycle of grapevine caused a reduction in both N nutritional status and grapevine vigor, and therefore cover crops could affect must quality in the first harvest after the cover crop was sown.

Leaf Blade versus Petiole Analysis for Nutritional Diagnosis of Vitis vinifera L. cv. Tempranillo

The temporal stability and the analysis reproducibility of nutrient concentration of leaf blades and petioles of Vitis vinifera L. cv. Tempranillo were evaluated at a vineyard representing the soil and climate conditions within the AOC Rioja region of Spain. Leaf blade and petiole were sampled throughout the growing season and analyzed for N, P, K, Ca, Mg, Fe, Mn, Zn, Cu, and B concentrations. For reproducibility of the analyses, leaf blade had a lower percent coeffcient of variation (%CV) of total N, and K than petiole, while petiole had a lower %CV than leaf blade for B. Phosphorus and Mg had similar %CV in blade and petiole at flowering, while blade had lower %CV at veraison for both nutrients. Calcium, Mn, and Fe had similar %CV in both tissues throughout the growing season. Seasonal changes of nutrient concentration in leaves confirmed the need for specific reference values for both leaf blades and petioles in each phenological stage. In general, nutrient concentration trends throughout the growing season showed short periods without differences between consecutive samplings near the 100% capfall phenological stage, while no statistical differences were found between samples obtained at any time throughout veraison. Results suggest that blade could be a more appropriate tissue for total N and K evaluation, whereas petiole is more appropriate for B evaluation. Calcium, Mn, and Fe will have a similar accuracy in both tissues at any phenological stage. While P and Mg had similar reproducibility in blade and petiole at flowering, blade seems be a better tissue for P and Mg nutritional diagnosis at veraison.

Catastrophic Unbalanced Genome Rearrangements Cause Somatic Loss of Berry Color in Grapevine

Chromothripsis-like genome rearrangements cause somatic loss of fruit pigmentation and alter sexual reproductive development in grapevine. Grape (Vitis vinifera) color somatic variants that can be used to develop new grapevine cultivars occasionally appear associated with deletion events of uncertain origin. To understand the mutational mechanisms generating somatic structural variation in grapevine, we compared the Tempranillo Blanco (TB) white berry somatic variant with its black berry ancestor, Tempranillo Tinto. Whole-genome sequencing uncovered a catastrophic genome rearrangement in TB that caused the hemizygous deletion of 313 genes, including the loss of the functional copy for the MYB transcription factors required for anthocyanin pigmentation in the berry skin. Loss of heterozygosity and decreased copy number delimited interspersed monosomic and disomic regions in the right arm of linkage groups 2 and 5. At least 11 validated clustered breakpoints involving intrachromosomal and interchromosomal translocations between three linkage groups flanked the deleted fragments, which, according to segregation analyses, are phased in a single copy of each of the affected chromosomes. These hallmarks, along with the lack of homology between breakpoint joins and the randomness of the order and orientation of the rearranged fragments, are all consistent with a chromothripsis-like pattern generated after chromosome breakage and illegitimate rejoining. This unbalanced genome reshuffling has additional consequences in reproductive development. In TB, lack of sexual transmission of rearranged chromosomes associates with low gamete viability, which compromises fruit set and decreases fruit production. Our findings show that catastrophic genome rearrangements arise spontaneously and stabilize during plant somatic growth. These dramatic rearrangements generate new interesting phenotypes that can be selected for the improvement of vegetatively propagated plant species.

Preliminary Diagnosis and Recommendation Integrated System Norms for Leaf Nutrient Diagnosis of Tempranillo Grapevine in the Rioja Appellation

Plant nutritional diagnosis requires specific reference levels for each grape variety to effectively reflect the nutritional status of the crop. A vine nutritional survey was undertaken in the Rioja A.O.C., northeastern Spain. The survey method was used to establish the preliminary norms in the application of the Diagnosis and Recommendation Integrated System (DRIS) to the nutritional diagnosis of leaf blade and petiole tissues of Vitis vinifera L., cv. Tempranillo, on Richter-110 rootstock. These DRIS norms were generated from data obtained during the course of 11 years (2000–10) from 166 vineyards trained on both Gobelet and Vertical Shoot Position (VSP) pruned Guyot and Double Cordon Royat systems. The database obtained includes information from different altitudes, soil types, cultural practices, and climatic conditions within the Rioja appellation. The majority of the vineyards had no irrigation and soil was tilled mechanically. Nitrogen, phosphorus, potassium, calcium, and magnesium were analyzed in leaf blade and petiole dry tissues sampled at both flowering and veraison. Vineyards with phytosanitary damages or flowering problems were discarded. Ratios among nutrients were established for the blade and petiole at both flowering and veraison by comparing two subpopulations of high and low quality. Both subpopulations were selected from a limited production criteria by a Students t-test mean comparison. Finally, DRIS norms for leaf blade and petiole at both flowering and veraison are proposed for the nutrition diagnosis of the cv. Tempranillo in the Rioja A.O.C.

Influence on wine biogenic amine composition of modifications to soil N availability and grapevine N by cover crops

BACKGROUND Vineyard soil management can modify the nitrogen soil availability and, therefore, grape amino acid content. These compounds are precursors of biogenic amines, which have negative effects on wine quality and human health. The objective was to study whether the effect of conventional tillage and two cover crops (barley and clover) on grapevine nitrogen status could be related to wine biogenic amines. Over 4 years, soil NO3- -N, nitrogen content in leaf and wine biogenic amine concentration were determined. RESULTS Barley reduced soil NO3- -N availability and clover increased it. In 2011, at bloom, nitrogen content decreased with barley treatment in both blade and petiole. In 2012, nitrogen content in both leaf tissues at bloom was greater with clover than with tillage and barley treatments. Also, total biogenic amines decreased in barley with respect to tillage and clover treatments. There were correlations between some individual and total biogenic amine concentrations with respect to nitrogen content in leaf tissues. CONCLUSION Wine biogenic amine concentration can be affected by the grapevine nitrogen status, provoked by changes in the soil NO3- -N availability with both cover crop treatments.

Comparison of DOP and DRIS Methods for Leaf Nutritional Diagnosis of Vitis vinifera L., Cv. Tempranillo

ABSTRACT Deviation from optimum percentage (DOP) and Diagnosis and Recommendation Integrated System (DRIS) are methodologies for leaf analysis interpretation. DOP calculates the deviation as a percentage for each essential element while DRIS calculates the average deviation for different ratios that include each element. A vine survey was undertaken for 11 years in La Rioja, northeastern Spain, to establish nutritional references for cv. ‘Tempranillo’ (Vitis vinifera L.). Diagnosis of nitrogen, phosphorus, potassium, calcium, and magnesium were performed by DRIS and DOP on the dataset for leaf blade and petiole, at both flowering (n = 684) and veraison (n = 801) with a moderate-yield criterion (3,800–10,000 kg·ha−1). Important differences between DOP and DRIS were found when a diagnosis using the same dataset was performed. In spite of the differences, the regression equations obtained are an acceptable adjustment between both methods for phosphorus (P) and magnesium (Mg) in blades and petioles, and for potassium (K) in blades.