The growth period of rice is divided into three stages:
1, vegetative growth period (from germination to young panicle differentiation)
2. vegetative growth and reproductive growth go hand in hand (from young panicle differentiation to flowering stage)
3. Reproductive growth stage (from flowering to maturity)
In tropical areas, vegetative growth and reproductive growth go hand in hand for 35 days, while reproductive growth lasts for 30 days.
The length of vegetative growth period varies with crop varieties.
For example, the whole growth period of IR64 is 1 10 days, and its vegetative growth period is 45 days; The whole growth period of IR8 is 130 days, and the vegetative growth period is 65 days.
The above three growth stages are composed of 10 different growth stages, which are respectively represented by numbers 0-9:
Stage 0 is the embryonic stage.
1 stage is seedling stage.
The second stage is tillering stage.
The third stage is jointing stage.
These three stages, 0,/kloc-0, 2 and 3, constitute the first growth and development stage of rice-the healthy growth stage.
The fourth stage is the guiding stage.
The fifth stage is heading stage.
The sixth period is flowering.
These four, five and six stages constitute the second stage of rice growth and development-the stage of simultaneous vegetative growth and reproductive growth.
The seventh stage is the milk ripening stage.
The eighth stage is the wax ripening stage.
The ninth stage is the mature stage.
The seven, eight and nine stages correspond to the third and last stage of rice growth (reproductive growth period).
Extended data
Key points of heading and flowering management
First, the problem of water.
The heading and flowering period of rice is the period with the largest physiological water demand in rice life, and it is also a period that is particularly sensitive to water.
First of all, we must ensure that there is no shortage of water and no drought. Generally, it is necessary to maintain a water layer of about 3cm in the field, so that rice plants can absorb nutrients smoothly, maintain the maximum photosynthetic efficiency, promote spikelet differentiation and reduce spikelet abortion.
It is best not to carry out deep-water irrigation during this period, so as to avoid the reduction of oxygen and vitality of roots, the obstruction of crop nutrients and the premature aging of rice.
Therefore, at this stage, it is best to ignore the previous water and give priority to intermittent irrigation to promote the maturity of rice plants.
Second, fertilization.
After rice enters the heading and flowering stage, try not to apply fertilizer. If the plant does not grow vigorously in the early stage, the leaves turn yellow at jointing stage, the leaves do not condense in the morning and the leaves are straight at noon, a certain amount of nitrogen fertilizer can be applied.
It is best to use "Bixi" and "Huo Yan" as foliar fertilizers with high phosphorus and potassium, which can prevent premature senescence of functional leaves, improve seed setting rate, increase 1000-grain weight and obtain high yield.
Third, how to use pesticides safely in rice flowering period
During this period, rice blast, sheath blight, stem borer, rice planthopper, rice leaf roller and so on. Mainly for control, efficient fungicides and pesticides must be selected, and the following points must be paid attention to when using pesticides:
1, safe drug use period
When rice blooms, Ying Shi's shell opens. If medicine is used at this time, liquid medicine and powder can easily enter flower organs, damaging pollen, anthers and ovaries, and at the same time, pollen will be washed away, affecting pollination, increasing empty grains and brown rice, and reducing rice yield.
The flowering period of rice is usually at 8- 13 o'clock and 9- 1 1 o'clock, so the drug should be used before 8 o'clock and after 4 o'clock.
Step 2 Use safe drugs
Because the newly extracted panicle tissue of rice is tender and weak in drug resistance, it is necessary to choose safe, efficient, low toxic and short residual period pesticides during this period.
Strictly control the dosage and concentration of pesticides, especially under the conditions of drought and air drying, and appropriately increase the dilution multiple when preparing liquid medicine to prevent phytotoxicity.