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Impact of application of urea modes and rates on yield and nitrous oxide emissions in grapevine (Vitis vinifera L.) on sandy soils in subtropical climate
Get PDFGrapevines subjected to applications of nitrogen (N) doses on the soil surface can use only a small amount of the nutrient, probably because of losses, such as nitrous oxide (N2O) emissions to the atmosphere. An alternative to reduce these N losses may be the application of N via fertigation. The study aimed to evaluate the N2O emissions and grape yield (Vitis vinifera L.), in grapevines submitted to the application of modes and doses of N cultivated in sandy soil in a subtropical climate. \u27Alicante Bouschet\u27 grapevines were subjected to a factorial scheme with three N rates: 0, 40 and 80 kg N ha-1 year-1; and two application modes: surface (NS) and via fertigation (NF). Evaluations of N2O emissions and ammonium (NH4+) and nitrate (NO3-) contents in the soil, N concentration in leaves, grape yield, and number of clusters per plant were carried out. Grapevines cultivated with applications of 40 and 80 kg N ha-1 yr-1, in NF and NS modes, respectively, present-ed higher N2O emissions. N2O emission peaks occurred in the first 9 days after N application. Cumulative N2O emissions ranged from 161.74 ± 34.67 to 496.18 ± 37.00 g ha-1 of N2O-N, in soils that received 0 and 40 kg N ha-1 yr-1, respectively, both in NF mode. Accumulated N2O emissions had a linearly positive relation with the mineral N content in the soil (NH4+ and NO3-) and these had a negative relation with grape yield.
Impact of mulch and irrigation treatment on growth, yield and fruit mass of sweet cherry
Get PDFIn einer Versuchsanlage der Süßkirschensorte \u27Bedel\u27 (Bellise®)/Gisela 5 (Pflanzabstand: 4,25 m × 2,35 m) wurde in den Jahren 2009–2018 der Einfluss von Mulchabdeckungen (Ziegelbruchstücke, Rasenschnitt, Fichtenholzspäne, Gerstenstroh) des Baumstreifens und zwei Bewässerungsvarianten ohne Mulchabdeckung auf Wachstum, Ertrag und Fruchtmasse der Bäume untersucht und mit einer unbewässerten Kontrolle ohne Mulchabdeckung verglichen. Bei den bewässerten Varianten wurde die eingesetzte Wassermenge pro Baum von täglicher Bewässerung bis zur Ernte (Zellteilungs- und Steinhärtungsphase: 2–4 l; Zellstreckungsphase: 4–8 l) mit Bewässerung nach der Saugspannung des Bodens in 25 cm Tiefe (200 hPa) miteinander verglichen.Die jährliche Niederschlagsmenge schwankte im Versuchszeitraum zwischen 340 mm und 640 mm. Die jährlich applizierte Wassermenge in den bewässerten Varianten schwankte zwischen 37 m3 ha-1 und 350 m3 ha-1. Durch Bewässerung nach der Saugspannung des Bodens konnte im Mittel der Jahre die Vorerntebewässerung um 24 % im Vergleich zur täglich bewässerten Variante reduziert werden, ohne Ertrag und Fruchtqualität negativ zu beeinflussen. Durch den Einsatz von Mulchabdeckungen des Baumstreifens (ohne zusätzliche Bewässerung) konnte der Ertrag im Mittel der Jahre im Vergleich zur Kontrolle um 2,4 kg pro Baum gesteigert werden, im Vergleich zu den bewässerten Varianten um 0,7 kg pro Baum. Dabei führte die Mulchabdeckung mit Rasenschnitt in vier von neun Versuchsjahren zu den höchsten Baumerträgen im Versuch.Die Ergebnisse zeigen, dass Mulchabdeckungen des Baumstreifens ohne zusätzliche Bewässerung bei Süßkirschen im frühen Reifesegment auf einem schluffigen Boden eine Alternative zu Bewässerung sein können.In an experimental orchard of the sweet cherry cultivar \u27Bedel\u27 (Bellise®)/Gisela 5 (planting distance: 4.25 m × 2.35 m), the influence of mulching the tree row (brick fragments, lawn clippings, spruce wood shavings, barley straw) as well as two different irrigation treatments on growth, yield and fruit mass of the trees was studied in the years 2009–2018 and compared with the performance of an unirrigated control without mulching. In the two irrigation treatments, the amount of water applied per tree was compared between daily irrigation until harvest (cell division and stone hardening phase: 2–4 l; cell extension phase: 4–8 l) and irrigation according to the soil water potential in 25 cm depth (200 hPa).The annual precipitation varied between 340 mm and 640 mm during the trial period. The annual amount of irrigation water applied varied between 37 m3 ha-1 and 350 m3 ha-1. By irrigating the trees according to the soil water potential, it was possible to reduce the pre-harvest irrigation by 24 % on average over the years compared to daily-irrigated trees, without any negative effect on yield and fruit quality. By mulching the tree row (without additional irrigation), the yield could be increased by 2.4 kg per tree on average over the years compared to the control, and by 0.7 kg per tree compared to the irrigated trees. Mulching with grass clippings led to the highest yields per tree in four of the nine years.The results show that mulching of the tree row without additional irrigation can be seen as an alternative to irrigation for sweet cherry cultivars in the early ripening segment grown on a silty soil
Analysis of Croatian wild and cultivated grapevine diversity by genotyping by sequencing
Get PDFMinor varieties represent a significant part of the grapevine germplasm (Vitis vinifera L. subsp. vinifera) in Croatia. During the long history of grape cultivation in insular, coastal and continental Croatia, numerous local varieties were cultivated, many of which are still used today. There are also several populations of wild grapevine (Vitis vinifera subsp. sylvestris Hegi Gmel) that have survived until the present in natural sites. Here, we developed a single primer enrichment technology (SPET) panel consisting of 61,308 probes for targeted sequencing of the V. vinifera gene space. In doing so, we examined a total of 28,092 gene models, 88.2% of all predicted genes, interrogating an average of 19 Mb nucleotides per individual genome, which corresponds to 4% of the haploid genome length. This is the first time that SPET-based sequencing has been applied to Croatian grapevine germplasm to generate multilocus genotype data of 126 cultivated accessions and 50 wild specimens. We identified 531,900 variants sites, 208,802 of which reside in coding sequences, 140,836 in introns, 118,416 in UTRs, and 63,424 in the nearby intergenic space that revealed the presence of 33 clonally propagated specimens representing both synonymies and clones within local varieties (22) as well as synonymies between local and international varieties (11), mostly from neighbouring countries. To investigate possible contribution of wild grapevine (Vitis vinifera subsp. sylvestris Hegi Gmel) to the development of present cultivars, four wild grapevine populations were included. None of the cultivated varieties showed close kinship with local wild specimens. This study opens new possibilities for studying the genetic diversity of Croatian grapevine germplasm and provides additional information with respect to SSR genotyping and phenotyping
Vitis labrusca L. germination: influence of treatments to break dormancy, storage and ripening point of fruits
Get PDFGrapevine seeds have morphophysiological dormancy, which complicates their germination, an important step in obtaining new plants after crossing during breeding. The objective of this work was to establish the ideal conditions for Vitis labrusca L. ‘Isabella’ seed storage conditions, the method for breaking seed dormancy, ripening of fruits at harvest, need for fungicide application before seed sowing and their germination. The seeds were submitted to three tests with (1 and 2) different treatments to break seed dormancy and storage in two conditions for two different times (Isabella), and (3) seeds from unripe and ripe fruits treated or untreated with fungicide. Germination was monitored two times per week. The percentage of germination (%G), germination mean time (GMT), and germination speed index (GSI) were calculated. Data were submitted to analysis of variance (ANOVA) and means were compared using the LSD-Fisher test (p < 0.05). The 12-month storage at a controlled temperature (25±2°C) provided the best germination results (up to 19.5% of G%). Stratification for 90 or 120 days on wet paper or sand at 5±2°C of seeds from mature fruits is the most suitable for the germination of Isabella seeds (65% to 72% of G%, and 1.73 and 1.95 of GSI for the treatments of stratification on wet sand for 120 days). It is also not necessary to apply fungicide on seeds before sowing, as long as disinfestation with 70% alcohol and sodium hypochlorite 1%, and triple washing with water is done (no statistical difference for seeds from ripe fruits treated or not with fungicide, 58% and 64.7% of %G, and 1.37 and 1.22 of GSI, respectively)
Spray drift from application of plant protection products with drones in vineyards
Get PDFEs wurden Feldversuche nach ISO 22866 zur Bestimmung der Abdrift bei der Anwendung von Pflanzenschutzmitteln mit Drohnen im Weinbau durchgeführt, um Messwerte zu gewinnen, die von Behörden für die Risikobewertung verwendet werden können.Verschiedene Oktokopter, die mit unterschiedlichen Düsen (Standard- und Injektordüsen) ausgestattet waren, wurden mit unterschiedlichen Applikationsparametern (Fluggeschwindigkeit, -höhe und –richtung) eingesetzt. Das Abdriftsediment wurde für Entfernungen bis 20 m bestimmt und mit den Abdrifteckwerten für den Weinbau für Bodengeräte und Hubschrauber verglichen.Im Vergleich zu den Werten für Hubschrauber ist die Abdrift für Drohnen im Weinbau wesentlich geringer. Werden Injektordüsen eingesetzt, sind die 90sten Perzentile des Abdriftsediments für Drohnen sogar geringer als die Abdrifteckwerte für Bodengeräte.Deshalb wird vorgeschlagen, Spritzeinrichtungen für Drohnen ausschließlich mit Abdrift mindernden Zerstäubern, wie Injektordüsen, auszurüsten. Unter dieser Voraussetzung können die etablierten Abdrifteckwerte für Bodengeräte im Weinbau auch für die Risikobewertung bei der Anwendung mit Drohnen verwendet werden.Field experiments according to ISO 22866 were conducted to determine the spray drift from Unmanned Aerial Spraying Systems (UASS) applying plant protection products (PPP) in vineyards in order to collect data that can be used for drift risk assessment by authorities.Different octocopters, nozzles (standard and air induction), application parameters (height, speed) and flight patterns (longitudinal and lateral flight lines) were used. The drift sediment at distances up to 20 m was compared to the German basic drift values for crewed helicopters and ground based air blast sprayers.In comparison to PPP applications with crewed helicopters, the spray drift risk is substantially lower when using UASSs. For air induction nozzles, the 90th percentile values of drift sediment are even lower than the basic drift values for ground equipment.This is why, similar to crewed helicopters, UASSs should be equipped with drift reducing atomisers, such as air induction nozzles. Providing this, the existing basic drift values for vineyards would apply also for drift risk assessment for UASS applications