On March 8, 2024, the team of Professor Zhang Chaohong of Northwest A&F University published an article “The Effect of 5-aminolevulinic acid on grape photosynthetic characteristics and fruit quality” in the Journal of Fruit Resources. Research results show that exogenous ALA can increase the chloroplast pigment content in grape leaves, increase Pn, Tr, Ci and Gs in grape leaves, thereby enhancing the photosynthetic accumulation capacity of grape leaves, and at the same time, it is beneficial to improve the quality and flavor of grape fruits.
5-Aminolevulinic acid (ALA) is a precursor for chlorophyll biosynthesis and plays an important role in physiological activities such as photosynthesis of plants.
This experiment took Kerisen seedless grapes under open field cultivation conditions as the research object. Grape leaves were sprayed with 10, 25, and 50 mg/L solutions respectively, and the control was clear water treatment (CK).
1. Effect on chlorophyll content of grape leaves
Under open field cultivation conditions, the chlorophyll and carotenoid contents of grape leaves increased to a certain extent after ALA treatment, among which the 25 mg/L treatment had the most significant effect.
2. Effect of ALA on photosynthesis of grape leaves
The net photosynthetic rate often determines the amount of photosynthetic accumulation products. It can be seen from the figure that ALA treatment at each concentration gradient significantly increased the net photosynthetic rate (Pn), transpiration rate (Tr), intercellular CO2 concentration (Ci) and stomatal conductance (Gs) of grape leaves, of which 25 mg/L The effect increased most significantly after 5-Aminolevulinic acid treatment.
3. Effect on grape fruit quality
The longitudinal diameter of fruit kernels after spraying with 10, 25, and 50 mg/L ALA was significantly higher than that of the control, and the 25 mg/L 5-ALA treatment had the best effect on increasing the longitudinal diameter of fruit kernels. Spraying ALA at various concentrations can significantly increase the TSS and solid-acid ratio of grapes, improving fruit flavor and taste. Among them, the TSS content of the 25 mg/L treatment is the highest.
4. Effect of ALA on grape fruit color
The brightness of the fruit surface in ALA treatment was lower than that in the control. Among them, the brightness of the fruit surface in the 25 mg/L ALA treatment was lower, and there was a significant difference. As the fruit color changes from green to red, ALA treatment improves the fruit color index of grapes, among which 25 mg/L ALA treatment has a better effect.
In summary, exogenous ALA treatment can increase the content of chloroplast pigments such as chlorophyll and carotenoids in grape leaves, and improve the net photosynthetic rate (Pn), transpiration rate (Tr), intercellular CO2 concentration (Ci) and stomata of grape leaves. conductance (Gs) and other photosynthetic indicators, thereby enhancing the photosynthetic accumulation ability of grape leaves. At the same time, it is helpful to improve the quality and flavor of grape fruits. Compared with 10 mg/L and 50 mg/L, 25 mg/L treatment had better overall effect.
