Improving Peach Fruit Yield and Quality Using Foliar Application of Nano Chelated Zinc and Seaweed Extract (Spirulina platensis): A Multivariate Analysis Approach.

The twenty-seven identical peach trees were exposed to different levels of a Nano Chelated fertilizer contain 12% Zn and Spirulina platensis liquid extract in a factorial experiment based on RCD, in order to enhance fruit yield and quality. The maximum values of leaf area (35.9 cm2), SPAD (51.2 value), fruit set (28.2%), fruit firmness (26.3 lb. inch-2), fruit diameter (137 mm), individual fruit weight (116.3 g), flesh weight of fruit (106.7 g), seed weight (9.6 g), fruit number per tree (534.7 n), fruit yield per tree (62.2 kg), fruit yield (31.5-ton ha-1), TSS (13.15°Brix), and vitamin C content (12.90 mg/100 mg FW) were obtained under application of Spirulina platensis at 2500 ppm plus Zn NPs at 6 mL L-1. Furthermore, the lowest fruit decay (33.33%) was observed under this combined treatment. Application of this treatment significantly improved leaf area (8.2%), SPAD (58.3%), fruit set (32.8%), fruit number (46.5%), fruit diameter (30.5%), fruit weight (41.7%), flesh weight (42.0), seed weight (37.9%), fruit yield per tree (107.5%), fruit yield ha-1 (107.5%), fruit firmness (62.9%), fruit decay (-44.5%), TSS (83.7%), and total phenol (6.6%ns) compared to control. Principal component analysis (PCA) confirmed results of means comparison and recognized 2500 ppm Spirulina platensis extract +6 mL L-1 Zn NPs as the optimal treatment to maximize yield and growth traits while maintaining low decay and high biochemical quality. Furthermore, Pearson's correlations and regression analysis revealed the strong positive relations between physical, morpho-physiological, and yield variables. Based on the results of univariate analysis and confirmation with multivariate analysis, Foliar application of 2500 ppm seaweed in combination with 6 mL L-1 Zn NPs has been recommended for the improvement of fruit quantity and quality in peach trees.