The use of water-soluble chemical fertilizers for years under drip irrigation conditions results in soil compaction, fertility decline, and fruit quality decrease in arid areas. Currently, little research has been reported regarding the effects of increasing organic fertilizer and reducing drip chemical fertilizer on the growth of grape plants under different conditions in arid areas. In this study, five different treatments were conducted. Compared with no fertilizer for 3 consecutive years (CK) and single fertilizer for 3 consecutive years (T0), organic fertilizer plus 1 year of reducing drip chemical fertilizer (T1), organic fertilizer plus 2 years of reducing drip chemical fertilizer (T2), and organic fertilizer plus 3 years of reducing drip chemical fertilizer (T3) improved the soil pH, electrical conductivity (EC) values, and soil organic matter content to different degrees during early growth stages (15 days after anthesis) and mature stages (75 days after anthesis). The available N, P, and K contents in the T1 and T2 treatments increased significantly. With the T2 treatment, the longitudinal and transverse diameters of the ‘Summer Black’ grapes were the largest during the two fruit expansion periods. The anthocyanin content of grape peel with the T2 treatment was 22.0% higher than that with the T0 treatment. The soluble solids, sugar–acid ratio, various sugar contents, vitamin C, and total phenol of the fruit increased significantly with the T2 treatment, indicating that the T2 treatment was best for promoting grape growth and fruit quality and that the T3 treatment was the second best.
Fengyun Zhao, Yu Jiang, Xiufeng He, Huaifeng Liu and Kun Yu
Fengyun Zhao, Junli Sun, Songlin Yu, Huaifeng Liu and Kun Yu
Aeration through subsurface drip irrigation (SDI) can promote plant growth and increase crop yield; however, more research is focused on annual crops, and there are few studies on perennial crops. We have studied a new type of SDI (SDI with tanks) suitable for cultivation and production of perennial fruit trees and photovoltaic aeration device in greenhouse. The results showed that aeration irrigation promoted the growth of new leaves, fine roots, and new branches of grape, regulated O2/CO2 content in rhizosphere soil, and accelerated air exchange in rhizosphere soil. This study showed that aeration irrigation did not change the structure of bacteria and fungi but significantly increased the abundance of aerobic bacteria, such as Nitrospira and Cytophagia. Moreover, it promoted the increase of Pseudomonas and Aspergillus related to phosphate solubilization, that of Bacillus related to potassium solubilization, and that of Fusarium related to organic matter (OM) decomposition. This study shows that aeration irrigation through SDI with tanks can promote grape growth, which may be related to the ability of aeration irrigation to change the gas composition of rhizosphere soil, optimize the structure of rhizosphere soil microorganism.
Zhijun Zhang, Huaifeng Liu, Junli Sun, Songlin Yu, Wang He, Tianyuan Li and Zhao Baolong
The use of resistant rootstocks is an inevitable trend in the development and production of grapes (Vitis sp.). The present study analyzed differences in the metabolites in grape seeds of different rootstock combinations (1103P, 5C, SO4, 3309C, 140R, and control) grafted onto ‘Cabernet Sauvignon’ (CS) wine grape (Vitis vinifera) scions (control, CS/CS, self-rooted grafting vines) using liquid chromatography–mass spectrometry (LC-MS) and nontargeted metabolomic techniques. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal-partial least squares discriminant analysis identified 30 significant metabolites and 22 metabolic pathways in the seeds of CS that differed significantly from the control seeds. This study revealed that rootstocks influence metabolite concentrations and metabolic pathways (alanine–aspartate–glutamate pathway, arginine-proline pathway, and the tricarboxylic acid cycle) in the scion onto which they are grafted. The rootstocks increased the concentration of delphinidin-3-(6-acetylglucoside), peonidin 3-(6-p-coumarylglucoside), L-threonine, and D-tartaric in CS seeds. Appropriate rootstock combinations can be used to improve the quality of grape seeds by changing the concentrations of amino acids, organic acids, polyphenols, and vitamin B. This study provides a theoretical basis for selecting grape rootstocks and provides important insights for improving the quality of commercial products derived from grape seeds.