Cover cropped and tilled table grape vineyard: Data on leaves and stems

Data presented are on mass, length, SPAD and some physiological parameters of leaves and stems in a table grape vineyard of Italia variety grafted onto 1103 Paulsen, covered with a plastic sheet to advance ripening and managed with two soil systems in the Puglia region, South-eastern Italy in 2015 and 2016. The two systems differed for the soil management since in one area of the vineyard a cover crop was used (Trifolium repens L.), whereas in the other area only soil tillage was adopted. The data of the two seasons include: (a) mass of leaves of primary shoot, secondary shoot and opposite the cluster; (b) length of secondary shoots; (c) number of both secondary shoots and leaves of secondary shoots; (d) SPAD values and area of leaves opposite both first and second cluster on the primary shoot; (e) mass of stems of both primary and secondary shoots; and (f) some physiological parameters (Ψstem, temperature, Fv/Fm). The data in this article support and augment information presented in the research article ‘Cover crops in the inter-row of a table grape vineyard managed with irrigation sensors: effects on yield, quality and glutamine synthetase activity in leaves’ (Sci. Hortic. 281, 2021 https://doi.org/10.1016/j.scienta.2021.109963).


Specifications
Agricultural Sciences Specific subject area Viticulture: soil management of the vineyard Type of data Table  Image  Figure Microsoft Excel raw data How data were acquired Samples of grapevine shoots were collected in the vineyard at the main physiological stages each season and carried to the lab for the successive analyses. Measurement of fresh mass (f.w.) of leaves and stems was done by using a scale and successively samples of all organs were dried in a ventilated oven (ORMA, model BC, Milan, Italy) at 65 °C until a constant mass for the dry mass determination (d.w.). Leaf area measurements were made with a leaf area meter (LI-3100 area meter, LI-COR Inc., USA). A chlorophyll meter (SPAD-502, Konica Minolta, Japan) was used to make Soil-Plant Analysis Development (SPAD) measurements of leaves (4 per vine) opposite the clusters. Stem water potential ( stem ) was measured on 3 healthy leaves per vine not exposed to the sun (3 vines per treatment). The leaves were selected and wrapped in polyethylene bags and covered with aluminum foil at least 2 h prior to the measurements. The stem readings were made at noon with a pump-up chamber (PMS Instrument Company, Albany, OR, USA). Temperatures of both berries and leaves were collected by using a portable infrared thermometer (PCE-777 N, PCE Italia, Capannori, Italy). The Fv/Fm ratio was obtained by using a pocket pea chlorophyll fluorimeter (Hansatech Instruments, Norfolk, UK).
Other vegetative data are reported in the related article [1] . Data format Raw Analyzed Parameters for data collection The experimental design adopted in the trial was a single factor (soil management) and two treatments (cover cropped and tilled) of 0.5 ha each. In 2015 and 2016, at each phenological stage according to the BBCH scale (BBCH 65; 71 75; 79; 83; 89) [2] , 9 shoots per treatment were sampled and used for the analyses. Description of data collection Two soil management systems were evaluated over a two-year period. Grapevine shoots collected at the six main phenological stages in each season were analysed in the lab: length of shoots, leaf area, weight of stems, leaf weight. Measurements of stem , temperatures and fluorescence were performed in the vineyard and data analysed in the lab.  The impact of cover crops in table grape vineyards covered with a plastic sheet is still poorly  investigated. This data could be valuable for future studies to understand the effects of cover  crops on the vegetative responses of both seeded and seedless table grape varieties.  • Data can also be taken into consideration from viticulturists for the use of an inter-row cover  crop in similar vineyard conditions to develop a more sustainable management of table grape vineyards. • The data may serve as a benchmark for future researches aiming at investigating the effects on vine of more sustainable managements of table grape vineyards in areas with a Mediterranean climate.

Data Description
This article includes the raw data, descriptive data (means) and statistics (95% confidence intervals with REGWQ test for stages comparison) on the effects of two soil management systems over a two-year period on the vegetative parameters of Italia table grape variety grown in Puglia region, South-eastern Italy. The data presented here include some vegetative parameters collected in the experiment, whereas the data of other parameters were used in the analyses reported in the related article [1] . Vegetative samples were collected at six phenological stages, according to the BBCH scale [2] . Data include: a) site localization (  ( Table 5 ); g) SPAD values and area of leaves opposite both the first and second cluster on the primary shoot ( Table 6 ); h) mass of primary shoot stems in 2015 and 2016 ( Table 7 ); i) mass of secondary shoot stems in 2015 and 2016 ( Table 8 ); l) stem , temperatures of leaves and berries and Fv/Fm ( Table 9 ). The raw data are provided in the Mendeley repository.
This important two-year study was carried out in the countryside of Adelfia (BA), an area very important and known since more than a century ago for the cultivation of table grape

Table 1
Mass of the primary leaves in 2015 and 2016. Letters within columns indicate significant differences (P < 0.05) between stages and for each parameter according to REGQW test. * , * * , * * * and ns indicate significance at P < 0.05, 0.01, 0.001 and not significant, respectively.

Location and experimental design
The trial was conducted over a two-year period (2015-2016) in two areas of a commercial 10year old 'Italia' table grape variety grafted onto 1103 Paulsen rootstock. The vineyard is located in the countryside of Adelfia (Bari province), Puglia region, South-eastern Italy at GPS coordinates lat. 40.970957, long. 16.852581 and elevation 218.5 m above sea level. Vines spacing 2.2 × 2.8 m and epsilon trellising system with four fruiting canes/vine (40-50 buds/vine). In February, as a traditional practice in the area in order to advance ripening, the vineyard was covered with a plastic sheet 160 μm thick and 150 g/m 2 , with 88% light transmittance and 35% light diffusion. The sheets were removed after harvest and before winter pruning. The data of soil analysis are reported in [1] , whereas fertilization schedule and irrigation volumes are reported in [3] and [4] , respectively. Apart from soil management and irrigation, all other managements (i.e., pest control, summer pruning, fertilization) were equivalent for the two vineyard areas [1] . Two different vineyard soil management practices were compared, cover crop, as recently introduced in table grape vineyards, and tillage, as the traditional practice adopted in the area. In order to compare the two managements, in the same vineyard (1 ha) two contiguous areas were used. The first trial area was seeded (50 kg/ha) with white clover ( Trifolium repens L.) only in the inter-row in November 2014, whereas the latter consisted of a traditional tilled soil. The experimental design was a single factor (soil management), two treatments (cover crop and tillage) of around 0.5 ha each. Each treatment consisted of three sampling areas (blocks) of 30 vines each (a total of 90 vines per treatment) with 10 vines per repetition (3 repetitions per block) and 6 tagged vines for the measurements. The tagged vines were characterized by a general uniform crop load and canopy as observed in the summer 2014 and during the growing season. In particular, the 30 vines were arranged in three rows of 10 vines per row (single repetition) separated from each other by at least one row and from the border by at least four rows.

Plant material sampling and analysis
The different annual organs of the vines (leaves and stems of the primary and secondary shoots) were sampled from the middle nodes of selected fruiting canes during the main phenological stages of each season (BBCH 65; 71 75; 79; 83; 89). A total of 9 shoots per treatment were sampled at each phenological stage (3 shoots/sampling area), enclosed in huge plastic bags, and quickly carried to the lab for all the analyses. Before destructive analyses, for each primary shoot, both the secondary shoots and their leaves were counted. The length of the secondary shoots was obtained with the use of a 5 m steel measuring tape self-retract flexible metric tape. Measurement of fresh mass (f.w.) of leaves and stems was done by using a scale. After detaching the leaves, leaf area measurement was made by using a leaf area meter (LI-3100 area meter, LI-COR Inc., USA). Leaf area was expressed as cm 2 (leaves opposite the clusters), and converted to m 2 for expressing the area of all the leaves opposite the clusters for each vine (leaf area of the single shoot × all shoots of vine at each stage). Successively samples of leaves and stems were dried in a ventilated oven (ORMA model BC, ORMA s.r.l., Milan, Italy) at 65 °C until a constant mass for the dry mass determination (d.w.). A chlorophyll meter (SPAD-502, Konica Minolta, Japan) was used to make the SPAD measurements of leaves (4 per vine) opposite the clusters. Stem water potential ( stem ) was measured on 3 healthy leaves per vine not exposed to the sun (9 vines per treatment). The leaves were selected and wrapped in polyethylene bags and covered with aluminum foil at least 2 h prior to the measurements. The stem readings were made at noon with a pump-up chamber (PMS Instrument Company, Albany, OR, USA). Temperatures of both berries and leaves were collected in the vineyard by using a portable infrared thermometer (PCE-777 N, PCE Italia, Capannori, Italy). The Fv/Fm ratio was obtained in the vineyard by using a pocket pea chlorophyll fluorimeter (Hansatech Instruments, Norfolk, UK).

Statistical analysis
Analysis of variance (ANOVA) was performed with XLSTAT-Pro-software (Addinsoft, Paris, France) at the P < 0.05 for comparison between phenological stages and at P < 0.05, 0.01 and 0.001 for the other analyses (treatment and year). The assumptions of variance were verified with the Levene test (homogeneity of variance) and the Lillefors and Shapiro-Wilk tests (normal distribution). The mean values obtained for the different factors were statistically separated by using the REGWQ test.

Ethics Statement
The work involved neither the use of human subjects nor animal experiments. Data were not collected from social media platforms.

CRediT Author Statement
Giuseppe Ferrara: Conceptualization, Data curation, Formal analysis, Methodology, Project administration, Resources, Supervision, Visualization, Writing -original draft, Writing -review and editing; Andrea Mazzeo : Data curation, Investigation, Methodology, Writing-Original draft preparation, Writing -review and editing.

Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships which have or could be perceived to have influenced the work reported in this article.