GiESCO 2017 – Session 7: Plant protection

Wine grape growers in California's North Coast region recorded severe outbreaks of the exotic pest, Virginia creeper leafhopper (VCLH) (Erythroneura ziczac) in 2011-2012, resulting in devastating damage, particularly in organic vineyards. An initial assessment determined that these outbreaks were due to a lack of biological control and poor understanding of management control practices for E. ziczac, which can easily be confused with the more common western grape leafhopper (E. elegantula).

The fungal diseases that affect grapevine wood are very limiting factors for viticulture and difficult to control. Several pathogens are associated with these diseases, such as the fungi of the family Botryosphaeriaceae. In this context, this work aimed to verify the effect of chemical fungicides, biological agents and plant extracts on the control of fungi Botryosphaeriaceae, causal agents of death and decline of the vines.

Environmental sustainability, linked to fungicide treatments, leads to a quest for innovative answers, which are closer to the environmental ones. In this context we included our experimental activity, developed in the harvests of 2013, 2014, 2015 and 2016, which is looking for innovative defense solutions in viticulture.

Lobesia botrana is a pest that attacks mainly the cultivation of the vine in Argentina, therefore it is essential to carry out controls to avoid losses in production. However, the use of insecticides can generate residues in the grape. In order to achieve an innocuous end product, suitable for consumption and competent in national and international markets, without exceeding the tolerances required, it is necessary to know the dissipation of insecticides in a field.

By the means of (i) a national data base providing information about the vineyard management practices of more than 5000 vine growers in France (for years 2006 and 2010) and (ii) data characterizing the main wine producing regions, the authors analyze the factors likely to explain the intensity of pesticide use in the French vineyard.

Substantial economic losses occur in grapevines due to Botrytis Bunch Rot (BBR). The control of this disease is still largely based on periodic anti-Botrytis specific fungicide spraying. Therefore, protection strategies must be optimized in order to reduce pesticide applications.

Through the damage of nematodes plant pathogenic funguses contribute to the final devastation of the grape in enhanced extent. We set it as an objective to examine the density and rate of fungi and nematodes of three vineyards thatonly differ in the cultivation methods applied on them which are Intensive, Extensive and None.

Pesticides in agriculture may cause undesirable effects on the environment. In Mendoza, these products are sprayed mainly for the control of Lobesia botrana and fungal diseases. The impact on agricultural environment may differ depending on the crop protection strategies.

The use of natural fertilizers such as silicon and calcium chloride is a potential strategy to improve grape resistance versus fungal diseases due to changes in berries physical characteristic and secondary metabolites synthesis.

The main strategy to control powdery mildew (Erysiphe necator [Schw.] Burr.) in Chilean vineyards is largely based on periodic fungicide spraying (up to 18 applications per season), which may lead to many environmental and human health risks.

In the present work it was proposed to evaluate the use of massive trapping for the control of the fruit fly complex that attacks the vine, using two types of food attractants; as well as determine the species and sex captured by them, and the level of crop damage. The adaptive research work was carried out in Tolombón- Cafayate- Salta- Argentina, during the 2015/2016, on a plot of 2 ha of grape variety TorrontésRiojano, conducted in horizontal roof.

Lobesia botrana is a quarantine pest for Argentina, detected in 2010 in Mendoza. Earlier stages of larvae feed on flowers and fruits. Wounds allow the development of fungi that decreases yield and quality. INTA is studying a phenological model based on day-degrees to predict the pest behavior. The study was conducted since 2015 in five different microclimatic growing areas of Mendoza. 30 pheromone traps have been used at each monitoring site.

Cultivated grapevine (Vitis vinifera) is highly susceptible to several fungal and fungal-like diseases such as powdery mildew (PM) and downy mildew (DM), which require large use of pesticides for their containment. In other crops, knock-out mutations of host genes controlling susceptibility to such diseases have proven a successful strategy to obtain resistant plants.

Field observations in Argentinean vineyards, have led to claim that phylloxera grow better in clay soils and under drip irrigation, than in sandy soils and flooding. The aim of this study was to assess phylloxera damagein vines under two irrigation methods orsoil textures in controlled conditions.

Powdery mildew (Erysiphe necator) (PM) is the most important and impacting fungal disease of grapevine (Vitis vinifera L). This disease remains difficult to model and forecast accurately because (i) the first signs of the disease in the vineyard are hardly noticeable in the first 30- 40 days after the onset of the epidemic (three to four pathogen generations), and (ii) its spatial distribution within or between neighboring plots is heterogeneous.