The timing of peach seedling seed collection is crucial for seed quality. When determining the maturity of fruit tree seeds, it is often based on the fruit changing to a mature color, softening, the seed coat darkening and becoming glossy, a reduction in seed moisture content, and an increase in dry matter, indicating fullness. Most fruit trees enter morphological maturity after physiological maturity, but only a few, like ginkgo, require a longer period after morphological maturity for the seed embryo to fully develop. Therefore, the fruits used for seed collection must be fully ripe and should not be harvested too early.

2. Seed Collection Method

(1) Composting methods: For fruits with no commercial value, such as hawthorn and mountain apricot, stack them in a shaded area to soften the flesh. During the composting period, turn the piles regularly to maintain a temperature of 25-30°C. Once the flesh is softened, crush it, wash with clean water, and extract the seeds.

(2) The fruit processing method can involve seed extraction during the process, with attention to prevent seed contamination or a decrease in seed viability due to temperature, chemical treatment, and mechanical damage.

Peach seedlings must be properly dried to prevent rotting during storage. The main factors affecting seedling physiological activity during storage are moisture content, temperature, humidity, and ventilation. Peach seedlings are typically dried in a cool, shaded area, allowing for natural air-drying and avoiding direct sunlight. After air-drying, the seeds should be graded, removing impurities and broken grains to ensure a purity of 95% or higher. Then, the seeds are further graded based on their fullness or quality. Once the seeds have been selectively graded, they can produce seedlings with uniform growth, making it easier to achieve full germination and facilitate nurturing and management.