Anti-hail Nets Research Articles

Changes in Song ThrushTurdus philomelosDensity and Habitat Association in Apple Orchards During the Breeding Season

Within-season changes in habitat and distribution of breeding birds have been poorly investigated but are likely to be important for several species. With this work, we investigated what factors affect the density of a multi-brooded bird species breeding in apple orchards, the song thrush Turdus philomelos, in three different periods of the breeding season in the Trento province, northern Italy. Birds were counted along transects, and analyses carried out using a Generalised Mixed Linear Model (GLMM) approach. A further analysis assessed the effect of conspecific occurrence and habitat variables on the changes in local density. Thrush density changed during the season, increasing from early to late period, and was mainly affected by tree height (positively), bare soil (negatively in third period), shrubland (negatively), wetland (positively), grassland (negatively), percentage of rows irrigated by droplet system (negatively), percentage of orchard covered by anti-hail nets (negatively), urbanised area (negatively in first period, positively in third period). Intra-seasonal variation in density was affected by tree height (positively), anti-hail nets (negatively), use of herbicide during the late period (negatively), difference in bare ground (negatively), and initial thrush density (negatively), the latter suggesting that best habitats are occupied first. Multi-brooded bird species may show varying density and changing species-habitat relationships during the breeding season, and their distribution could change during the period of reproduction. This pattern could apply to a large number of bird species, requires deeper investigation and could have important implications for conservation and management.

TREE VIGOR, FRUIT YIELD AND QUALITY OF NECTARINE TREES GROWN UNDER RED PHOTOSELECTIVE ANTI-HAIL NETS IN SOUTHERN ITALY

In Italy, hailstorms represent a major threat for fruit tree cultivation. Therefore many peach growers have protected their orchards with anti-hail nets. Many studies have demonstrated that photoselective shade nets can induce interesting photomorphogenic effects on several cultivated species. The aim of the present research was to study the effect of red photoselective anti-hail nets on nectarine tree vigor, fruit yield, and fruit quality. The study was carried out in a private orchard located in Eboli (Southern Italy) on mature nectarine trees ‘Laura’ grafted on GF677. On February 2008, five rows of trees were covered with a red photoselective anti-hail net (30% shade factor), whereas another five rows were covered with a white, transparent anti-hail net (10% shade factor) that is the most common type of anti-hail net used in the area. During the experiment a number of parameters related to tree vigor, fruit yield and quality were measured. Trees under the red net had higher light interception than trees under the white net and this suggests that the red net induced an increase in tree vigor, as previously reported for other species. Net color did not significantly affect the number of fruit per tree and fruit yield. Similarly, there were no significant differences in fruit size distribution or fresh fruit weight between trees under the two types of nets. Both cover and ground color of fruit skin was slightly, but significantly, less under red nets. On the other hand, fruit of trees under the red net tended to have significantly higher flesh firmness, lower soluble solids content and lower percent dry matter than fruit of trees under the white net. These effects may be related to a slight delay in fruit maturation induced by the red net or to a negative effect of this net on sugar accumulation in the fruit (potentially because of the higher shade factor of the red net compared to the white net).

The effect of anti-hail nets on fruit protection, radiation, temperature, quality and probability of Mondial Gala apples

The effect of anti-hail nets on fruit protection, radiation, temperature, quality and probability of Mondial Gala apples