Effects of Canopy Position and Microclimate on Fruit Development and Quality of Camellia oleifera

Abstract

Camellia oleifera is an economic tree species in southern China and is famous for its oil. The surrounding climate is filtered by the tree itself, resulting in the canopy microclimate, which affects the growth and fruit quality of C. oleifera. This study investigated the effect of canopy positions on microclimate and fruit growth, maturation and qualities by comparing the differences in canopy position. This study also considered the relationship between microclimate and fruit qualities during the oil conversion period. The fruit qualities and microclimate were studied by dividing the canopy into two vertical layers and horizontal layers, creating the following canopy positions: upper outer canopy (UO), upper inner canopy (UI), lower outer canopy (LO) and lower inner canopy (LI). The light intensity increased significantly from inside to outside and from top to bottom in the canopy; however, there were no significant differences in temperature and relative humidity. At maturity, the moisture content of fruits and kernels in UO and LO was approximately <5% of those in UI and LI. The soluble sugar content increased by 10.90%, 8.47% and 6.84% in UO, UI and LO in November, while no significant change was observed in LI. The kernel oil content (KOC) obtained a higher value in UO and UI at maturity. However, KOC decreased by 5.16%, 3.02%, 3.10% and 0.67% in UO, UI, LO and LI in November. Light intensity in September and October was correlated, and temperature and relative humidity in August and September were correlated.

The Combination of High-Light Efficiency Pruning and Mulching Improves Fruit Quality and Uneven Maturation at Harvest in Camellia oleifera

“…Our results showed that temperature and humidity demonstrated no significant differences, but a significant difference was observed in light intensity among the four canopy positions (Figure 2). This was consistent with the conclusions of Wen et al [31], Lu et al [37]. The closer to the inner canopy position, the greater the humidity, the lower the temperature, which is inconsistent with the results of flavedo studies [39], Sapindus mukorossi Gaertn [30], and Xanthoceras sorbifolium [32] studies.…”

“…To alleviate the drought stress faced by C. oleifera during the growing season, our laboratory evaluated the soil water retention effect of various mulching materials and their effects on yield and quality and determined that organic mulching was an ideal mulching material [14]. In addition, our laboratory has also carried out canopy microclimate research on multiple tree species and has shown that thinning flowers or fruits, adjusting the type of fruiting branch group, or changing the tree structure can regulate yield and quality [30,31,36,37]. Unfortunately, studies on the combination of aboveground and belowground regulatory techniques are rare.…”