A study was conducted in a commercial sweet cherry orchard in central Chile. The objective was to evaluate the rain cover effect on changes in the microclimate, vegetative growth, plant physiology and fruit quality of ‘Rainier’, ‘Bing’ and ‘Sweetheart’ sweet cherry trees. The data were compared to a control without a rain cover. The results showed that, under the rain cover, there was a 50–60% reduction in total solar radiation, as well as an increase in air temperature (+0.6 °C) and a decrease in relative humidity (−4.7 percentage points) in the upper canopy zone. Regarding the trees under rain cover, a greater shoot length (28–58%) and leaf area (24–54%) were observed among cultivars compared to the control; the trunk cross-sectional area was only significant in ‘Rainier’, it being 1.2 times greater under rain cover. CO2 assimilation showed no differences, but an increase in the leaf transpiration rate was observed. The fruit firmness and sugar content in fruits were negatively affected by the rain cover, those characteristics being of major relevance for the cherry growers. Additionally, the contents of anthocyanins and carotenoids and the antioxidant capacity were significantly lower only in ‘Rainier’ under rain cover, while the total phenol content decreased in all three cultivars. The rain cover did not negatively affect the tree physiology, but it can be detrimental in bicolor cultivars with a yellow flesh due to a lower color and phenolic compounds development.
The success of establishing fruit orchards has traditionally been attributed to the vigor of the nursery plant used. This study aimed to evaluate the post-transplant survival, canopy growth and fruit productivity of two sweet cherry (Prunus avium L.) cultivars (‘Lapins’/‘Colt’ and ‘Regina’/‘Gisela 12’) with different radicular basal volumes of 100%, 50% and 25% and nursery plant types: (i) bare root (BR) or (ii) bagged (B). The initial stem diameter of the plants ranged from 12 to 19 mm, and their height ranged from 1.4 to 1.8 m. Plants grafted onto ‘Colt’ rootstock exhibited twice the initial root volume compared to those grafted onto ‘Gisela 12’. Evaluations were carried out in three commercial orchards during three seasons in the Central Valley of Chile. The results indicated that root volume and nursery type did not affect plant survival and productivity. For ‘Regina’/‘Gisela 12’, only the bag treatment resulted in less trunk cross-sectional area (TCSA) and shoot length, and for ‘Lapins’/‘Colt’, the BR25 treatment showed a lower initial TCSA than other treatments, although without a negative effect on yield. Hence, the presumption about the influence of root volume and plant type on the successful establishment of a sweet cherry on ‘Colt’ and ‘Gisela 12’ rootstock can be discarded. The survival, growth and precocity of the orchard depend more on post-planting conditions and water management than on the number or type of nursery plant roots. It is important to prioritize proper post-planting care and water management for optimal orchard health.