What month is the tillering stage of rice? How long? What kind of fertilizer? Attached management measures

Tillering is an inherent physiological characteristic of rice. Rice tiller is essentially the branch of rice stem, the time of tiller occurrence and the height of node position have significant influence on tiller growth and panicle formation. What month is the tillering stage of rice? How long? How to manage?

Time of rice tillering

Rice from transplantation to young panicle differentiation to tillering stage, this process takes about 30 days (depending on varieties, planting period and seedling raising methods, and there are changes), most of them begin to enter tillering stage in June. The tillering stage can be divided into green stage (transplanted), effective tillering stage and ineffective tillering stage.

Rejuvenation stage: Transplanted seedlings, due to damage in the process of pulling, transporting and transplanting seedlings, are called plant injuries. Therefore, after transplanting, it takes a period of time to recover and turn green and grow new roots. This period of time is called the green period. The length of green period was related to the size of plant injury, the green period was shorter for small plant injury and longer for large plant injury. Generally, it can be returned to green after 5~7 days. For example, early rice is easy to return green when it is planted in sunny and warm days, and late rice is easy to return green when it is planted in cool days; the seedling shovelling is earlier than the seedling pulling, and some of the shovelling seedlings do not return green period (that is, they will not turn yellow after planting).

Effective tillering stage: after returning to green, if conditions are appropriate, new plants can be extended from axillary buds at the base of pseudostems, which is called tillering. When 10% of the plants in the whole field have tillering, it is the initial tillering stage; when 50% of the plants have tillering, it is the peak tillering stage; when 80% of the plants stop tillering, it is the final tillering stage. When the number of tillers and the number of tillers grown into the same number of ears, said effective tiller stage. Under normal circumstances, tiller began after about 10 days, most of the tillers can grow into ears.

Ineffective tillering stage: generally after transplanting 20~25 days after the occurrence of tillering, most of them stop growing in the middle and can not produce ears, in fact, is a waste of nutrients, so called ineffective tillering. This is called the ineffective tillering stage. Therefore, effective measures should be taken to promote early tillering and multiple tillering before the effective tillering termination period, that is, within 20 days after transplanting, and ineffective tillering should be controlled after the effective tillering termination. In this way, rice panicles can be more and bigger, and the shadow phenomenon in the field can be reduced to achieve stable and high yield.

Management measures of rice tillering stage

1. Apply tiller fertilizer early

30% of the total nitrogen fertilizer was applied immediately after the rice returned to green or 3~4 days after transplanting. Tillering fertilizer was applied twice, 80% of the total amount of tiller fertilizer was applied to the whole field in the first time, and the remaining 20% was applied to the field at the 6-leaf stage of 11-leaf varieties. Tillering fertilizer can be applied with 3~4 kg ammonium sulfate under the premise that the total amount of fertilizer is unchanged. If tiller fertilizer is applied late, it will lead to a large number of ineffective tillers and premature closure. Too much nitrogen at the peak tillering stage resulted in overlong basal internodes and reduced lodging resistance.

2. Shallow water irrigation

After the rice returns to green and survives, shallow water irrigation is carried out, and the irrigation depth is 3~5 cm. Intensive intermittent irrigation is adopted for high fertility fields at the beginning and peak of tillering, light intermittent irrigation is adopted for medium fertility fields, and shallow irrigation at the beginning of tillering and intermittent irrigation at the peak of tillering can also be carried out according to the seedling situation; shallow wet irrigation at tillering stage can enlarge the oxidation layer, increase the number of nitrogenating bacteria, organophosphorus bacteria and cellulose decomposing bacteria, promote the decomposition of organic fertilizers and the release of nutrients, and improve the nutritional conditions of rice. The comprehensive effect of these irrigation methods is to promote early tillering, multiple tillering and increase the effective tillering rate of rice.

3. Disease and pest prevention

To achieve prevention first, comprehensive control, highlighting a "early" word, especially the prevention and control of rice blast according to the rice field leaf age process timely disease prevention.

1. Rice leaf miner: at the initial stage of larvae, 70%(imidacloprid) water dispersible granules 4~6 g/mu; or 25%(thiamethoxine) water dispersible granules 6~8 g/mu; or 40% dimethoate 100 ml/mu, mixed with 5 liters of water mist spray.

2. Rice negative mud insect: When the larvae damage has a tendency to increase, 2.5% cypermethrin EC 15~30 ml/mu or 2.5% cyhalothrin (kung fu) EC 30 ml/mu can be used for spraying control.

3. Leaf plague: When spores are found in the field and leaf plague spots are found on the leaves, 40% tricyclazole 40~50 ml/mu, or 20% tricyclazole 100 ml/mu, or 75% tricyclazole 20~30 ml/mu, mixed with water 5 liters mist machine stem and leaf spray, or aerial chemical spray control.

How to manage rice at late tillering stage

The low temperature in 2018 caused the rice tillering quantity to be generally insufficient, with one tiller less than that in normal years. At present, at the end of June, rice has entered the late tillering stage for six times, and is at 7.1-7.5 leaves. There are still January-2 tillering that can be won, i.e. the 8th leaf co-tillering and the secondary tillering of the 2nd leaf. By about July 10, rice enters the jointing and booting initial stage. This platform should remind farmers that they must master the following points in rice management:

1. Promoting tillers: shallow water should be adopted to promote tillers, keep the water layer 2-3 cm, not deep water, not heavy sun. If there is bubbling, peculiar smell, black root, gray root, or root system extending upward and other oxygen deficiency or toxic gas concentration is too high in the field, water should be withdrawn to dry the field, that is, there is no water on the mud surface of the field but water in the foot nest. After oxygenating and strengthening the root, new water should be supplied in time. Shallow water can balance the temperature difference between day and night, improve the mud temperature and promote the growth of tiller buds.

2. Fertilization: Rice enters 8 leaves is the period of applying regulating fertilizer, but it should be noted that the amount of fertilizer applied to 8 leaves only accounts for about 10% of the total amount of nitrogen applied in the whole growth period, and it should not be too much, otherwise the fertilizer effect is reflected in 10 leaves, which is the stage of spikelet differentiation and jointing of rice, which will cause the elongation of the first internode at the base and easy lodging. If the field is uneven, green and yellow uneven, or there is no fertilizer, nitrogen fertilizer should be supplemented in time to prevent fertilizer from affecting tillering or causing unbalanced field growth. Ammonium sulfate is recommended at a dosage of 50-60 kg/ha. Fertilization depends on the field growth, color deep concentration does not topdressing, yellow, thin, short to adjust appropriately.

If the seedling growth is weak, at the end of tillering stage, it can be sprayed once with special foliar fertilizer for Israeli rice, which has a good effect on rice seedling quality, strong seedling and accumulated temperature.

Third, water layer: 8 leaf stage should be carried out to control tillers, tillers insufficient plot, it is recommended to delay the drying of the field, shallow water to promote tillers, to June 25 after the field reached 600 plants per square meter before drying the field. If there is odor or bubbling and other anoxic conditions can be air-field oxygenated strong roots, restore root vitality. Tillering enough to timely sun-dry fields, to be sun-dried before jointing, sun-dry field standard is the surface when there are microcracks and then new water. After jointing, the method of "shallow-wet-dry" irrigation was adopted to ensure that the roots did not lack oxygen. July 10-20 is the meiosis period of rice. In case of low temperature below 17 ℃, deep water should be used to protect seedlings. It is suggested to supply water at night when the temperature is low, or to enter the field through sunning pool.

IV. Weeding: For plots with more weeds in the field, it is recommended to adopt the method of stem and leaf treatment, mainly with bentazon, and try not to use 2-methyl-4 chlorine during tillering to prevent phytotoxicity. Rice barnyard grass can be controlled by cyhalofop-methyl. Rice at tillering stage is sensitive to pesticides, and herbicides with high safety should be selected.

V. Disease prevention: For plots with large fertilizer amount and density, if long-term irrigation will cause rice root hypoxia, small root quantity, weak growth, low disease resistance and lodging resistance, easy to occur sheath blight, rice blast, etc., sheath blight is an important factor causing lodging and yield reduction.

Prevention and control methods: must adhere to the "shallow-wet-dry" irrigation method, that is, before the water does not see the water. Every time, we should wait for the field surface to dry until there are microcracks before adding new water, so as to discharge toxic gases, restore root vitality, and improve disease resistance and lodging resistance.

The second is rational use of chemicals, must be shallow-wet-dry cases to restore the root system after the use of drugs, otherwise the efficacy is not high. It is recommended to use the medicine with good reputation on the market, strictly according to the instructions, when using medicine, first prepare mother liquor and then mix with water spray.