Conventional irrigation methods decrease greenhouse soil aeration, which leads to restricted root growth and reduced soil fungal abundance in greenhouse grapes. In this study, aerated irrigation equipment was used to investigate the effects of aerated irrigation on the biomass accumulation, root growth, and soil fungal community structure of grape seedlings. The results show that aerated irrigation significantly increased the root length, root surface area, root volume, and number of root tips by 38.5%, 32.1%, 62.1%, and 23.4%, respectively, at a soil depth of 20–40 cm (p ≤ 0.05). The chao1 index and ACE index of fungi at different soil depths under aerated irrigation were higher than those without aerated treatment; aerated irrigation changed the relative abundance of dominant fungi in rhizosphere soil. At a soil depth of 20–40 cm, aerated irrigation increased the abundance of Fusarium by 42.2%. Aerated irrigation also contributed to the abundance of the beneficial fungal genera Mortierella, Cladosporium, and Glomus. At a soil depth of 0–20 cm, the abundance of Mortierella in the soil that received aerated treatment was 180.6% higher than in the control treatment. These findings suggest that aerated irrigation is a promising strategy for the promotion of grape root growth and biomass accumulation, and it can also increase the abundance of some beneficial fungi.

As a widely distributed fruit, grapes are susceptible to oxidative damage during storage and transportation, resulting in declining quality and commodity value. This study aimed to investigate the effects of preharvest application of different concentrations of multi-walled carbon nanotubes (MWCNTs) on the postharvest quality of ‘Flame Seedless’ grapes. The results showed that low-concentration (25 and 50 mg L⁻¹) MWCNTs treatments maintained the comprehensive quality index, firmness, soluble sugar, titratable acid, pH value, and ascorbic acid (AsA) content of grapes. MWCNTs at 25 and 50 mg L⁻¹ increased the activities of peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and ascorbic acid (APX). Furthermore, MWCNTs reduced the malondialdehyde (MDA) content and decreased the accumulation of excessive reactive oxygen species (ROS) in grape peel and pulp tissues. In addition, transmission electron microscopy (TEM) images demonstrated that MWCNTs were absorbed by parenchymal cells in the grape peel and pulp through the epidermal cell layer. MWCNTs with a specific concentration can be used as a new inducer for the biosynthesis of antioxidants to reduce oxidative damage in grapes during storage.

Ethylene is commonly used in agricultural production for fruit ripening and degreening. However, further exploration is needed on how to apply it in its gaseous form in practical production. This study compared the effects of ethylene gas (E1: 100 ppm, E2: 120 ppm, E3: 150 ppm) application via subsurface drip irrigation (SDI) and fruit surface spraying of ethephon solution (ETH) on the quality and coloration of ‘Flame Seedless’ grape fruit during veraison. The effects of applying ethylene gas via SDI were most pronounced at 3, 6, and 9 days post-treatment. At day 6 post-treatment, E2 had a higher soluble solid content (SSC), solid–acid ratio, and anthocyanin content than ETH, although by day 15 most differences among the ethylene gas treatments, ETH, and CK had diminished. E2 also increased the abundance of 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACO) and ACC synthase (ACS) and the expression of VvCHI, VvCHS, VvGST, and VvF3H at day 3 post-treatment, and all of these were also higher than in the ETH treatment. The gaseous nature of ethylene allows it to contact the fruit effectively and to be taken up by the plant through multiple pathways, so that the grapes respond faster to ethylene gas than to ETH treatment.