Edible Fungi Preservation Methods and Herbaceous Flower Seed Storage

I. Post-harvest Handling

1. Clean and sort the flower seeds properly. After the seeds are harvested, they must be cleaned. Whole plants pulled up should be dried before threshing; for those harvested together with the fruit, the peel, flesh and various attachments must be removed. Flower seeds are small and light; some seed coats bear fine hairs or short spines and easily adhere to or become mixed with viable impurities such as sclerotia, insect galls, insect eggs and weed seeds, as well as non-viable impurities such as dead leaves and sand.

2. Dry them properly. If herbaceous flower seeds need sun-drying after harvest, they must be dried together with the fruit husk. Do not place the seeds on a cement drying yard or in a metal container under direct sunlight, otherwise the vitality of the seeds will be affected. The seeds can be spread on canvas, reed mats or bamboo mats to dry. Some seeds are sensitive to light, so natural air-drying can be used: place the seeds indoors in a ventilated, rain-sheltered place and let them dry naturally. Generally, the safe moisture content for herbaceous flower seeds is below 7%.

II. Key Points of Storage Technology

1. Choose the correct packaging method. Flower seeds are generally small in quantity, short-lived and expensive, so in most cases polyethylene-aluminum foil composite film bags are used, usually with a paper seed bag as the outer sleeve. Flower seeds containing aromatic oils should be stored in metal cans, wooden boxes or colored glass bottles. Cans and foil bags can also be vacuumed or semi-vacuumed when sealed to reduce the amount of oxygen in the container. The seed bag should be clearly marked on the outside with the seed name, the year, month and day of harvest, and the useful life.

2. Low-temperature, moisture-proof storage. Seeds that have been cleaned and dried to a safe moisture content and packed in foil bags or metal cans should be stored under dry, sealed, low-temperature (2-5°C) conditions. Seed bags or cans should be placed on a shelf or platform about 50 cm above the ground; never let the seed bags touch the ground directly, to prevent moisture damage. A small amount of seed can be stored in a desiccator. A glass bottle, a small-mouthed jar with a lid, a plastic bucket, etc. can serve as the desiccator; place quicklime, silica gel, dry plant ash or charcoal at the bottom as a desiccant, put the seed bag on top, then seal it tightly and place it in a low-temperature, dry place.

III. Lifespan of Herbaceous Flower Seeds

Seeds are alive, and the strength of their vitality and the length of their lifespan are closely related to storage conditions. Seeds under warm, humid, well-ventilated conditions have intense life activity, the nutrients inside the seeds are quickly consumed, and the seed lifespan becomes shorter; seeds that have lost their viability cannot be used for sowing and raising seedlings. Seeds under low-temperature, dry, slowly ventilated conditions have slow life activity, and the seed lifespan can be relatively extended. Therefore, seeds of 1-2 year herbaceous flowers should be kept under low-temperature, dry, sealed conditions. Seeds with a storage life of 1 year include Phlox drummondii, Kochia scoparia and Primula: those with a storage life of 2-3 years include Cleome spinosa, Eschscholzia californica, Viola tricolor, Tagetes erecta, Verbena hybrida, Callistephus chinensis, Bellis perennis, Tropaeolum majus, Lathyrus odoratus, Papaver rhoeas, Cleome spinosa, Salvia splendens, Helichrysum bracteatum, Antirrhinum majus and Centaurea cyanus: those with a storage life of 4-5 years include Portulaca grandiflora, Zinnia elegans, Cheiranthus cheiri, Coreopsis tinctoria, Matthiola incana, Petunia hybrida, Amaranthus tricolor, Celosia cristata and Calendula officinalis.

IV. Management Measures for Flower Seed Storage

1. Clean and disinfect the warehouse. Remove garbage, chemical fertilizers, pesticides and so on from the warehouse, and lay felt paper or similar material inside as a moisture-proof layer to reduce the ground moisture absorbed by the seeds. Dilute 80% dichlorvos emulsifiable concentrate and spray it, keep doors and windows tightly closed for 48-72 h (hours), then ventilate for 24 h (hours). Do not fumigate the warehouse.

2. Stack them properly. There are many varieties of flower seeds of different grades, but generally the quantity of each kind of seed is not large. In the warehouse they should be placed on a shelf about 50 cm from the wall and 50 cm above the ground, with clear labels indicating their position, quantity, packaging and so on, to prevent mixing.

3. Ventilate at the right time. Seed respiration produces a great deal of heat, and timely ventilation can lower the temperature and remove moisture. The general principle is: "ventilate on clear days, keep closed on rainy days, do not ventilate in snow, ventilate when it is so cold that dripping water freezes, open early and close late and open less at noon, and do not open when there is fog at night." Natural ventilation is mostly used, and mechanical ventilation can be used where conditions permit.

4. Check frequently. The warehouse should be inspected promptly, and after the seeds pass through summer or winter, the seed moisture content and germination rate should be tested. Set temperature and humidity meters at multiple points in different parts of the warehouse, measure them at fixed times by assigned personnel, and keep good records. The low-temperature, low-humidity environment for flower seed storage must be maintained to prevent the seeds from molding or the germination rate from declining.