High yield and good quality cultivation techniques of Black Rice

Black rice is an ancient and valuable kind of rice in China. It is rich in nutrition and has the function of nourishing yin and tonifying blood, black hair and anti-aging. It has always been eaten as a tonic. It is known as Buxue glutinous rice, Jiegu glutinous rice, medicinal rice, longevity rice and moon rice. Black rice is mainly distributed in Yunnan, Guizhou, Guangdong, Guangxi, Hunan and Shaanxi provinces. In the long-term cultivation process, many precious farm varieties have been formed, such as Yunnan Jinggu purple rice, Guizhou Huishuihei, Guangxi Donglan Mo rice and Hunan southwest Hunan black glutinous rice. But these varieties generally have tall plants, loose plant types, drooping leaves, long spikes, sparse grains, no disease resistance and easy lodging, with a yield of only 100,200 kg per mu (1 mu = 667 square meters, the same below).

In recent years, through systematic breeding, radiation mutagenesis and hybrid breeding, a number of black rice varieties with short stalk and high yield have been cultivated, such as Dwarf Xuenuo, Zixiangnuo, Xiangxuenuo, Zaoheinuo and Longqing 4, etc. the yield per mu can reach 300 to 450 kg, or higher, and it has been planted in a large area. In order to further develop black rice, the cultivation techniques of high yield and high quality of black rice are introduced as follows.

The main results are as follows: (1) timely early sowing: because black rice is a temperature-sensitive variety, it is required to sow from March 10 to 15, which can prolong its growth period and advance heading and pollination before the high temperature in late July, so as to improve yield and rice quality.

(2) dry cultivation of many tillers and strong seedlings: select a hill (piece) of sandy loam field or dry land around the field with leeward to the sun and convenient for drainage and irrigation to cover and raise seedlings with thin film, sowing 4.5 kg per mu and 1.5 kg per mu.

(3) to improve the transplanting quality: transplanting in east-west direction, wide rows and narrow plants, large seedlings with soil, 30 ~ 320000 basic seedlings per mu, so that they no longer tiller. The row spacing of wide and narrow plants is generally 10 cm × 22 cm, which can increase ventilation and light transmission, help to grow healthily, have large panicles and many grains, and improve rice quality.

(4) increase the application of phosphorus and potassium fertilizer, little or no lime: according to the soil survey data, the content of available potassium in general soil is low, and the content of phosphorus is also very low in some areas, so increasing the application of phosphorus and potassium fertilizer is an important measure to improve the quality of black rice. Phosphate fertilizer is mainly used as base fertilizer, potassium fertilizer is mainly combined with the first ploughing and topdressing, a small amount of supplementary application is applied at booting stage, and phosphorus and potassium fertilizer can be foliar sprayed before and after heading. If black rice absorbs too much calcium, the rice looks rough and tastes bad, so the fields where black rice is cultivated should apply little or no lime.

(5) use little or no pesticides as far as possible: pesticide residues will endanger the health of human, livestock and poultry and reduce the quality of black rice. therefore, in the prevention and control of diseases and insect pests, comprehensive control measures based on agricultural control should be taken, including the selection of varieties resistant to diseases and insect pests, treatment of diseased rice straw, salvage of residues, shallow irrigation of open fields, timely drying of fields, removal of paspalum grass, use of local methods to control diseases and insect pests, etc. In order to control and eliminate diseases and insect pests without pesticide residue.

(6) Water should not be cut off too early in the later stage: cutting off water too early in the mature stage of black rice will not only increase the empty shell rate, reduce 1000-grain weight and yield, but also affect the quality of black rice. Generally, black rice should be cut off about 6 days before harvest.

(7) early harvest at the right time: the late harvest of black rice will cause the rice to be tasteless and the grain thick and hard, so it is necessary to harvest 85% of the rice when it is mature.

(8) pay attention to improving the method of drying grain: black rice is exposed to the hot sun after harvest, and rapid dehydration and drying will increase the rate of broken rice when milling rice, so it can be spread 7-10 cm thick at the beginning of drying, so that it can be turned over frequently to prevent dehydration too fast. special attention should be paid not to exposure on the cement ground.

(9) speeding up propagation and continuous purification and rejuvenation: black rice varieties are very precious. In order to speed up breeding, strong seedlings can be sparsely sown. When the tillers of seedlings reach 7 to 8, one tiller can be planted separately into a single plant, so that 100 grams of seeds can be planted in 1 mu of Honda. Before harvest, 3040 seeds (that is, seeds with strong genetic parts) from the upper part of the main ear with the characteristics of this variety, large panicle and strong resistance were selected to be the seeds of the next generation seed field or the seeds of high-yielding key fields, in order to continuously purify and rejuvenate and improve yield and quality.