Search Results (3)

Torreya grandis Fort. ex Lindl. cv. “Merrillii” is an important woody oil crop, and the development of plantations relies on the cultivation of high-quality saplings. For this study, 6-year-old grafted T. grandis saplings, which will soon be planted on the mountain, were selected to investigate the regulatory effects of nitrogen (N), phosphorus (P), and potassium (K) on their growth and morphology. To determine the optimal dosage and ratio of N–P–K fertilizer for sapling cultivation, we employed a three-factor four-level L16 (4³) orthogonal experiment design. The experiment included a total of 17 treatments—a control group where no fertilizer was applied and 16 treatments with varying levels of NPK supply. We conducted a one-season experiment under a prescribed fertilizer regime and measured root collar diameters and sapling heights, the root, shoot, leaf biomass, total biomass, and the nutritional status of plant organs (root, shoot, leaf). From these measurements, we calculated the root–shoot ratio (RS) and seedling quality index (QI). The application of N–P–K fertilizer exhibited significant benefits for T. grandis sapling cultivation, promoted their growth and biomass accumulation and altered the nutrient allocation patterns in organs. Ultimately, we determined the ideal N–P–K ratio for T. grandis growth to be 1:0.46:0.75, with a fertilizer application of 1.38 g·sapling⁻¹ of N, 0.64 g·sapling⁻¹ of P (P₂O₅), and 1.04 g·sapling⁻¹ of K (K₂O). Full article

Loquat is a nutrient-rich fruit with juicy and sweet pulp, but it is vulnerable to rot and deterioration without proper postharvest preservation measures. This study aimed to improve the postharvest quality of loquat by developing a microemulsion system based on an essential oil extracted from the Torreya grandis cv. Merrillii aril (TaEO), which has antimicrobial and antioxidant properties. An optimal TaEO microemulsion (TaEO-ME) was formulated, using a mixture of Tween-40 and Tween-80 as the surfactant, 1-butanol as the co-surfactant, and TaEO as the oil phase, with mass ratios of 9:1, 3:1, and 6:1, respectively. Two TaEO-ME formulations with 60% and 70% water contents were stable for 180 days at room temperature, with a mean droplet size below 12 nm and polydispersity index less than 0.24. They also exhibited higher stability and enhanced biological activities compared to free TaEO. Loquat fruit treated with TaEO-ME displayed a reduced decay index and lower membrane lipid peroxidation after 15 days of storage at 15 °C, as indicated by the lower malondialdehyde content and higher peroxidase activity. Moreover, the TaEO-ME treatment preserved the nutrient quality by maintaining the total phenolic compounds and ascorbic acid content. Our findings suggested that TaEO-ME can be used as a substitute for chemical preservatives to keep fruits fresh. Full article

As an important economic tree species, Chinese Torreya (Torreya grandis cv Merrillii) has been widely planted in the subtropical regions of China. However, it remains to be studied whether morphological traits are the key factors reflecting or affecting the green nut yield of Chinese Torreya, which is necessary for breeding research and plantation management. Therefore, in Zhuji in the Zhejiang Province, the central production area of Chinese Torreya, we investigated the morphological traits (height, ground diameter, under-crown height, crown width, and branching amount) and green nut yield of 120 randomly selected Chinese Torreya. Our results indicated that the differences in the morphological traits among Chinese Torreya individuals were relatively small, but those in the green nut yield traits were great. There was highly significant (p < 0.01) correlation between green nut yield and crown area and between green nut yield and root collar diameter (ground diameter). A moderate relationship (r = 0.38; p < 0.05) was observed between green nut yield and crown area, while a weak relationship (r = 0.294; p < 0.05) was detected between green nut yield and ground diameter. Tree height and branching amount had positive effects on green nut yield through other morphological traits, and under-crown height had indirect negative effects on green nut yield. Linear regression analysis showed a significant linear positive correlation between green nut yield and crown area, ground diameter, and crown width in the north–south and east–west directions (p < 0.01). These findings imply that if the tree height is fixed, increasing the ground diameter and crown area, appropriately increasing the branching amount, and reducing the under-crown height could be potential technical measures to improve the green nut yield of Chinese Torreya. Our study provides background information on green nut yield and its morphological traits in Chinese Torreya. Full article