Anti-hail nets are widely used in the main apple-producing areas to protect fruit against hailstorms and hail damage. It has been shown that the use of anti-hail nets also has beneficial effects against pests in apple orchards, especially against Lepidoptera species such as codling moth (Cydia pomonella (L.).The anti-hail nets form a physical barrier to the entry of adult moths and prevent associated fruit damage to apple orchards. However, the use of anti-hail nets can modify the orchard microclimate and reduce the interception of light.
It is well known that there is a close relationship between apple orchard light interception and productivity. A reduction in the interception of light can affect the acids/soluble solids ratio and the development of colour in apple skin, which is largely due to the accumulation of anthocyanins
Italian scientists evaluated the effect of anti-hail nets use on codling moth infestation and organoleptic quality of apple fruits (cv. Braeburn) grown in northern Italy in the Alto Adige region. Volatile compounds, sugar and organic acid composition, total phenol content and sensory characteristic of apple fruits were measured.
Results of the study are published on Journal of Science Food and Agriculture and available on line from June 17th 2015.
Results showed a consistent reduction of the percentage of apple fruits infested by codling moth as a result of the use of anti-hail nets during two consecutive harvest years (2011-2012). Their use did not affect fruit maturity, but reduced the skin colour, sugar content, pulp total phenol content, volatile compound composition and sensory characteristics.
However, the results were inconsistent over the two years apart for total phenols, formation of two volatile compounds (butyl and hexenyl acetate, the first being one of the main odorants in most apple cultivars), sensory attributes of ‘flavour of lemon’ and ‘juiciness’. For these parameters, the fruits from plots where the trees were not covered showed higher values than those from plots covered with anti-hail nets.
Scientists conclude that the use of anti-hail nets was able to prevent and reduce the attack of codling moth on apple fruits, confirming the findings reported in the literature and obtained in different regions of the world and with different varieties. The obtained results suggest that the anti-hail nets can be used in organic apple growing as a tool for preventing codling moth infestations, being the chemical pesticides forbidden in organic farming.
The use of the anti-hail nets affected the organoleptic quality characteristics of apple fruits in each harvest year, but the trend over the years was not clear owing to season-to-season variability. The results suggest that the effects of the use of anti-hail nets on the organoleptic quality characteristics could be relevant in determining consumers acceptability of apple fruits.
The present study was carried out as part of the project ‘BIOQUALIA’, funded by the Italian Ministry of Agriculture, Food and Forestry Policy.
Source: Irene Baiamonte, Antonio Raffo, Nicoletta Nardo, Elisabetta Moneta, Marina Peparaio, Antonio D’Aloise, Markus Kelderer, Claudio Casera, Flavio Paoletti, 'Effect of the use of anti-hail nets on codling moth (Cydia pomonella) and organoleptic quality of apple (cv. Braeburn) grown in Alto Adige Region (northern Italy)', 2015, Journal of Science Food and Agriculture
Contacts:
Flavio Paoletti
Council for Agricultural Research and Economics (CRA) – Research Centre on Food and Nutrition (CRA-NUT)
Via Ardeatina, 546
00178 Rome, Italy
Email: flavio.paoletti@entecra.it