How to maintain the quality of saved rice and wheat seeds?
In recent years, as the planting benefits of rice and wheat have declined, some wheat and conventional rice growers have begun saving their own rice and wheat seeds to reduce planting costs. Will farmers' saved grain seeds affect rice and wheat yields? How can the quality of saved rice and wheat seeds be ensured?
1. Large growers mostly buy commercial seed
Large grain grower Ye Zhiguang planted 177 mu of wheat. “I used to save my own seed after every wheat harvest for use in the next year's wheat planting, but in recent years I have bought commercial seed entirely.” He said the germination rate of commercial seed is generally above 85%, and high-germination commercial seed can reach 95%. If saved seed is not stored properly, its germination rate will be more than 10% lower than that of commercial seed. Like Ye Zhiguang, Wang Peifu, who plants 114 mu of wheat, also mainly buys commercial seed each wheat planting season. He said that for large growers, saving seed not only takes up storage space, but also requires hiring people to sieve and purify it, which is too much trouble.
Another farmer friend, Huang Qiyue, plants only 5 mu of conventional japonica rice. He told the reporter that after each japonica rice harvest, in order to reduce planting costs, he saves the japonica rice seed to be used the following year. Wang Huiting, who runs a chain store, told the reporter that for conventional japonica and glutinous rice growers, the proportion of farmers saving their own seed is noticeably higher. Locally, japonica and glutinous rice growers with a planting scale below 100 mu mainly use saved seed, while those above 100 mu still mostly buy commercial seed.
2. A gap in planting returns
Why are large wheat growers unwilling to save their own seed? According to analysis, if farmers save their own seed, to ensure the seedling emergence rate, the sowing rate per mu must be increased by 50-60 jin. Calculated at a wheat market purchase price of 1.1 yuan/jin, the seed cost per mu is between 55-66 yuan (excluding labour). If farmers buy commercial wheat seed, calculated at an average market selling price of 2.5 yuan/jin and a sowing rate of 30-40 jin per mu, the seed cost per mu is between 75-100 yuan. Comparing the two, the cost of buying commercial seed is only 20-34 yuan/mu higher than that of saved seed. But if farmers store saved wheat seed poorly, the wheat yield from saved seed is about 100 jin lower per mu than that from commercial seed. Calculated at a wheat market purchase price of 1.1 yuan/jin, each mu of wheat produces 110 yuan less, and after deducting the difference in seed cost, the return from wheat grown with commercial seed is 70-80 yuan/mu higher. But for scattered small growers, the total amount of wheat seed used is not large, it is also easy to store, and it can reduce planting costs. Therefore, some small-scale growers still prefer to keep part of the wheat seed after each wheat harvest for use the following year.
“My japonica rice planting area is not large, so I have to be careful with planting costs.” Huang Qiyue said that the sowing rate for both commercial seed and saved seed is between 18-20 jin/mu, but the cost for farmers using commercial japonica rice seed is 90-120 yuan/mu, while using saved seed costs only 36-40 yuan/mu. From the perspective of planting cost accounting, farmers using saved seed can save more than 50 yuan/mu.
Wang Huiting said that for local farmers growing conventional japonica and glutinous rice, if they use commercial seed, calculated at a sowing rate of 8-9 jin per mu and a market selling price of 5 yuan/jin, the seed cost per mu is 40-45 yuan; if farmers use saved seed, at a sowing rate of 9-10 jin per mu and a saved seed cost of 2 yuan/jin, the seed cost per mu is 18-20 yuan. Farmers generally buy commercial seed once every three years, using saved seed in two of those years, saving 44-50 yuan/mu in planting costs for japonica and glutinous rice over two years.
3. The storage environment is very important
Wu Wenge, director of the Cultivation Office of the Rice Research Institute of the Provincial Academy of Agricultural Sciences, believes that although from the perspective of high-yield agriculture and standardised agriculture, farmers saving their own seed is not advocated, conventional rice varieties can be saved, and this also helps farmers save on planting costs. Dr. Chen Gang told the reporter that if farmers want to save their own seed, the moisture content of the rice seed must be controlled below 14.5%, and they must have the technical ability to remove impurities and purify it. If conditions permit, the storage temperature for saved seed is best kept at around 10°C; at room temperature, the storage temperature for saved seed is also best kept below 25°C. Otherwise, if the storage temperature is too high, it will affect the vigour of the saved conventional rice seed.
The reporter learned that if farmers want to save their own wheat seed, they should carry out impurity removal work in the early stage before the wheat harvest. At wheat harvest, the wheat should be harvested separately, dried separately and stored separately. When drying, it should be dried separately on its own drying yard, not dried on the same yard as other varieties and ordinary wheat, to prevent mixing. When storing, the variety name should be marked on it to prevent confusion with other varieties and ordinary wheat, and it must not be stored in the same place as ordinary wheat. Before storing wheat seed, farmers should repeatedly dry it so that the moisture content of the wheat seed reaches the safe storage moisture level; the safe storage moisture content for wheat is below 13%. Farmers need to pay special attention that rice seed and wheat seed should be stored in a dry, ventilated place, and the bottom of the container holding the seed should be lined with moisture-proof materials such as wooden boards and stones.