How does the Super Dry Rice 1 variety perform?

Super Dry Rice 1 is a new super-high-yield dry rice variety bred by the China National Rice Research Institute. Results from plantings in Hangzhou and Hainan show that this dry rice variety has strong stress resistance, high and stable yield, and above-average grain quality, with broad application prospects, especially when planted as an early crop (dry season) in Hainan and South China, where it has considerable yield-increasing potential and great value for development and promotion. The characteristics and key cultivation techniques of Super Dry Rice 1 are briefly introduced as follows:

1. Characteristics of Super Dry Rice 1

1. Main agronomic traits

Super Dry Rice 1 was planted as a demonstration in the Hainan dry season, sown on November 25, 1998, and harvested on April 2, 1999, with a whole growth period of 127 days. Plant height 101 cm, moderate plant and leaf type, strong tillering ability, about 210,000 effective panicles per mu, medium panicles, an average of about 95 filled grains per panicle, seed setting rate above 90%, and 1000-grain weight 24 g. The flag leaves are upright, and in the late stage the stems stay green, yellow ripen, and color-change well, with a general yield of about 400 kg per mu. Super Dry Rice 1 has strong field resistance to diseases and insect pests, and its grain quality is above average.

Super Dry Rice 1 has a very strong ratooning ability. If the late stage of the first crop is managed properly and field management is strengthened after harvest, it is expected to produce ratoon rice with a relatively high yield.

2. Drought resistance

In 1998, a drought resistance evaluation was carried out by the Agronomy Department of the China National Rice Research Institute. From the evaluation results, Super Dry Rice 1 showed high resistance (Super Dry Rice 1 was grade 1, while the control dry rice variety Qin'ai was grade 3). Super Dry Rice 1 has strong field drought resistance, and even under the severe drought in Hainan (winter 1998 to spring 1999), it still showed very strong yield potential.

2. Key cultivation techniques for Super Dry Rice 1

1. Intensive farming and careful preparation

The quality of plowing and land preparation directly affects the uniform emergence and full stand of dry rice, as well as the soil's water-holding capacity. Therefore, a good environment must be created for the underground growth and development of dry rice.

1.1. Deep plowing: The suitable soil tillage depth for dry rice planting is 18-20 cm, but the plowing depth must also be determined according to soil fertility and thickness.

1.2. Land preparation: The requirements for careful land preparation are level soil, with ditches on four sides and a middle ditch, capable of both drainage and irrigation, generally with a ditch depth of 16 cm and a ditch width of 33 cm. Land should not be prepared too early, so as to avoid weeds growing; it may be prepared at sowing time, and sowing can be carried out immediately after the soil is broken up. For mountainous land and relatively wasteland plots, it is best to spray a strong herbicide such as glyphosate or Roundup 15 days in advance before land preparation to clear weeds and prevent weeds from harming the seedlings.

2. Sowing

The process before and after sowing consists of sunning the seed, soaking the seed, chemical treatment, setting the sowing date, designing the sowing method, sowing the proper amount, covering with soil, and so on.

2.1. Sunning the seed: Before sowing, sun the seed to help increase the germination rate and germination vigor of the seeds.

2.2. Seed soaking and seed disinfection: The purpose of soaking the seed is to allow all seeds to evenly absorb enough water, germinate uniformly, and emerge early, which also helps promote early development to a certain extent. The suitable soaking time is 24 hours. Use strong chlorinated disinfectant. The specific method is to first soak Super Dry Rice 1 for 12 hours, then pour in an appropriate amount of strong chlorinated disinfectant powder, stir evenly, and continue soaking for 8 hours, then rinse clean with clear water. Because the temperature in Hainan is relatively high, there is no need for pregermination; generally after soaking for 24 hours, the seeds can be sown once they show white.

2.3. Sowing period: For planting in the Hainan dry season, it is more suitable to arrange the sowing period around November 25, which can avoid the low-temperature weather in mid-March and early April and allow the dry rice to flower and pollinate safely.

2.4. Sowing method: Direct sowing is used, preferably in wide rows, with a row spacing of 33-40 cm; hole sowing may also be used. This method adopts wide rows and narrow plant spacing, with a row spacing of 26-28 cm and a plant spacing of 16-18 cm.

2.5. Sowing rate: The general sowing rate is about 4-6 jin per mu. For row sowing, calculate in advance the area of each field per mu, then weigh the appropriate amount of seed before sowing, so as to avoid too much or too little. For hole sowing, sow about 6 seeds per hole.

2.6. Soil covering: The depth of soil covering is related to whether dry rice emerges uniformly, and directly affects the germination rate and emergence rate of dry rice, and even affects yield. A general covering depth of 3-5 cm is suitable; too shallow or too deep will affect the seed germination rate and emergence rate.

2.7. Timely thinning: Whether dry rice is row sown or hole sown, thinning and replanting are needed to ensure a full stand and achieve the ideal number of seedlings.

3. Fertilization

Applying sufficient base fertilizer, applying topdressing appropriately in stages, controlling nitrogen fertilizer, and increasing organic fertilizer and phosphorus and potassium fertilizer are important fertilization principles for dry rice.

3.1. Base fertilizer: It accounts for 70-80% of the total fertilization amount. Generally, after plowing, apply 40 kg of phosphate fertilizer, 10 kg of potassium fertilizer, and 5 kg of urea per mu (when nitrogen, phosphorus, and potassium fertilizers are not used, 40 kg per mu of compound fertilizer may be used), and 20 loads of organic fertilizer.

3.2. Topdressing: When the seedlings have 4 leaves, apply 8 kg of urea per mu (best if it rains; if it does not rain, it may be applied with water). At the tillering stage, apply urea once as topdressing, 10 kg per mu.

4. Water management

Depending on the situation, a small amount of water may be irrigated at different growth stages of dry rice. 1-2 days after sowing, an appropriate amount of water may be irrigated to promote uniform seed germination. The irrigation water should preferably not exceed the ditch surface; otherwise, the field soil will become compacted, which is unfavorable for the growth and development of dry rice and affects its yield. At the booting stage, appropriately irrigating with running horse water (preferably not exceeding the ditch surface) helps to a certain extent with panicle-grain structure, heading uniformity, and increasing the yield of dry rice.

5. Weed control

Weed control is key to dry rice management. Weeds must be controlled at different stages, and as far as possible no weeds should be visible in the field. Generally, using Roundup 15 days before sowing to kill field weeds gives a relatively good effect. Chemical weed control may also be carried out after sowing and before emergence, with 75 ml of 60% butachlor emulsifiable concentrate plus 100 g of 50% prometryn wettable powder per mu, mixed with 50 kg of water, sprayed on the soil.

6. Disease and insect pest control

The primary pests in dry rice production are underground pests, among which mole crickets are the most serious. Controlling mole cricket damage is key to dry rice production. Before sowing, use 0.5 kg of carbofuran per mu to treat the seed and control underground pests. Within one week after sowing, use 2-3 liang of 90% trichlorfon crystals, first melt them with 3-4 jin of hot water, then mix with roasted and fragrant rice bran to form a tofu-dregs-like consistency, and scatter it in the field on a clear evening when there is no wind, preferably in sections where mole crickets are relatively serious. For thrips control at the seedling stage, and in the middle and late stages, before sowing use 2-3 kg of carbofuran per mu, mix with 10 kg of fine soil, and broadcast it on the soil surface to control underground pests; for thrips control at the seedling stage, and for control of stem borers, rice leaf rollers, rice planthoppers, and so on in the middle and late stages, use 100 ml of methamidophos + 200 ml of bisultap per mu, mixed with 50 kg of water, and spray; in the middle and late stages, pay special attention to controlling sheath blight, leaf blast, neck blast, grain blast, and other diseases, using 300 ml of jinggangmycin or Fuji 1 per mu, mixed with 50 kg of water, and spray.

In the early stage of dry rice, prevent damage by rats (especially at the seedling stage); poison bait may be placed before sowing to lure and kill rats, and rat poison may also be placed after sowing to kill rats. From the late heading stage to mature harvest, special attention should be paid to preventing damage by birds and livestock.