Abstract

Protected fruit crops started in Chile with the implementation of covering structures over ten years ago. Currently, there is a wide range of covering materials of different textures, spectral composition, and light scattering patterns in the market. However, little information exists about experiences on covering systems in Chilean kiwifruit orchards. This technology is mainly used to protect vines from adverse climatic events or to prevent bacterial canker. During the 2019-2020 season, a trial was conducted on ‘Hayward’ and ‘Jintao’ cultivars under different covering materials. The aim was to determine the effect of photo-selective nets and plastic films on productive and fruit quality parameters. In ‘Hayward’ a photo-selective white net, and in ‘Jintao’ a yellow LDPE (low-density polyethylene), and pearl gray HDPE (high-density polyethylene) plastic covers were installed above the vines at the beginning of September 2019. From December 2019 until harvest, biweekly fruit diameter growth was evaluated in the field. At the same time, 15 fruits per treatment were collected to measure destructive and non-destructive fruit quality parameters in the laboratory. At harvest, yield efficiency was determined as the total number of fruits collected per plant and total weight. The variables of TCSA (trunk cross-section area) and intercepted PAR (photosynthetically active radiation) were determined for each plant. The results showed that ‘Hayward’ vines under photo-selective net exhibited a significant increase in fruit weight at harvest in comparison to the uncovered control. Coverage treatments did not affect productive parameters such as yield efficiency and crop load. On the other hand, ‘Jintao’ presented differences in crop load. Vines under LDPE film showed a lower crop load than the control and HDPE film treatments. However, the LDPE film gave similar values of fruit weight as the control. In both cultivars, fruit quality parameters showed no notable differences.