Which cultivation aspects are influenced by the use of anti-hail netting?
Anti-hail netting is extensively used in stone and pome fruit growing areas in the north of Spain. Its primary function is to protect the crop from hail damage, but it also influences other aspects of these fruit trees:
INFLUENCE OF ANTI-HAIL NETTING ON THE PLANTATION MICROCLIMATE
- Reduces evapotranspiration (up to 11% in summer):
- Increased relative humidity (between 2 to 6%).
- Reduced plant water stress, due to the increase in relative humidity under the netting.
- Irrigation water savings.
- Reduces wind speed:
- Contributes to reduce evapotranspiration.
- Reduces damage from stalks and flower drop.
- Reduces losses due to fruit drop.
- Modifies temperatures:
- Reduces the orchard’s maximum temperatures.
- Increases the minimum temperatures.
INFLUENCE OF ANTI-HAIL NETTING ON FRUIT QUALITY
- Modifies the PAR radiation reaching the plant: it can influence important aspects such as size, coloration, skin quality, sugar content, etc.
- Improves the overall quality of the skin, reduces the number of:
- Sunstroke or sunburn
- Certain physiological alterations.
- Significantly reduces the incidence of severe russeting, if combined with other agrotextiles (anti-hail + plasticized netting).
- Influences fruit coloration: The selection of netting color should be determined by the variety, taking into account the color of the fruit, to prevent it from reducing its intensity, as follows:
- Black netting is mainly used on green and yellow varieties (‘Granny Smith’ and ‘Golden’).
- White and grey netting in two-colored varieties (‘Gala’, ‘Fuji’, ‘Pink Lady®’…).
- Influences soluble solids content and therefore days of maturation.
INFLUENCE OF ANTI-HAIL NETTING ON PLANT VIGOUR
- Increase in tree vigour, which could be explained by the positive effect of shade (especially in black netting), which would cause a significant reduction in both the radiation reaching the trees and, consequently, in the level of evapotranspiration.
- Reduction of plant water stress.
- Increased photosynthesis.
- Increased availability of carbohydrates.
Fuente: The effect of anti-hail nets on fruit protection, radiation, temperature, quality and profitability of ‘Mondial Gala’ apples. Journal of Applied Horticulture, 8(2): 91-100, July-December, 2006. Ignasi Iglesias* and Simó Alegre Institut de Recerca i Tecnologia Agroalimentàries (IRTA). Profruit. PROTECCIÓ DE LA FRUITA FRONT LES PEDREGADES. IRTA. Informe 2016.