Abstract: From January 28 to February 22, 2022, most of the country's cane areas were significantly low in temperature, significantly more precipitation, and significantly less sunshine, which was not conducive to the late growth and sugar accumulation of sugarcane, and the sowing and germination of newly planted cane. In addition, since January 27, most of the cane area has maintained a long period of low temperature and rainy weather, affecting the progress of sugarcane cutting, and the cane areas in central Guizhou and northern Guizhou have suffered mild cold and frost damage. It is estimated that the precipitation in Guangxi in the spring (March-May) is 10% to 20% less in the southeast of Guangxi, and 10% to 20% more in most other areas; the average temperature is 0.1 to 1 °C in the southwest of Guangxi, and the rest of the areas are 0.1 to 1 °C higher. Meteorological conditions in March are more favorable for sugarcane harvesting, spring planting of sugarcane seedlings and growth in most sugarcane areas, but the minimum temperature in Guangxi before February 26 is still low, and it is still necessary to guard against the adverse effects of frost weather on sugarcane.
First, the early growth meteorological conditions and impact analysis
From January 28 to February 22, 2022, the average temperature in most of the cane areas of the mainland was 5.5 to 19.1 °C, which was 2.0 to 6.7 °C lower than the same period of the year (Figure 1); the rainfall was 28.3 to 272.5 mm, which was 2 to 5.6 times more than the same period of the year, of which most of the cane areas in Guangxi were more than 3 times more (Figure 2); the number of sunshine hours was 8.1 to 191.8 hours, which was 10% less than the same period of the year. The temperature in most cane areas is significantly low, the precipitation is significantly more, and the sunshine is significantly less, which is not conducive to the late growth and sugar accumulation of sugarcane, and the sowing and germination of newly planted cane. In particular, since January 27, most of the cane areas have maintained long-term low temperature and rainy weather, resulting in large soil moisture in the cane fields and wet and slippery roads in the cane areas, which is not conducive to the harvesting, transportation and squeezing of sugarcane, affecting the progress of sugarcane cutting and transportation; in addition, the cane areas in central Guizhou and northern Guizhou have suffered mild cold frost damage, and the local cane areas in Luocheng, Meltwater and Xiangzhou have suffered moderate frost damage (Figure 3), which has a certain impact on the sugarcane sugar content and yield.
Figure 1 Average temperature distance distribution from January 28 to February 22, 2022 (green area is sugarcane planting area)
Figure 2 Rainfall leveling distribution from January 28 to February 22, 2022 (green area is sugarcane planting area)
Figure 3 Monitoring distribution of advection freeze damage in sugarcane, Guangxi on February 21, 2022
2. Weather forecast and possible impact analysis
1. Forecast of climate trends in spring 2022
It is estimated that the precipitation in Guangxi in the spring of 2022 (March-May) will be 10%-20% less in southeast Guizhou, and the remaining areas will be 10%-20% more; the average temperature in southwestErn Guangxi will be 0.1-1°C, and the rest of the areas will be 0.1-1°C higher. It is estimated that the precipitation in Western Guixi and Northern Guizhou in March is 20% to 40%, and the rest of the areas are less than 10% to 30%, and the average monthly temperature in Guangxi and coastal areas is 0.1 to 1.0 °C, and the rest of the areas are 0.1 to 1.0 °C. It is expected that the main cooling and precipitation period in March will appear roughly in: 6-14 days, there is moderate rain, local heavy to heavy rain; 23-26 days there is heavy rain, local heavy rain.
2. Weather forecast for the coming week
It is estimated that in the coming week of Guangxi (February 24 to March 1), the average weekly temperature will be mostly 2 to 3 °C lower in the whole region, and most of the weekly rainfall in the whole region will be 70 to 90%; the low temperature will be maintained before the 26th, and the maximum temperature in various places will gradually rise from the 24th. The specific forecast is as follows: from the 24th to the 25th, the whole region will be cloudy to sunny; there will be frost or freezing in the alpine mountains and parts of northern Guizhou, and there will be frost in southern Guizhou. The minimum temperature in various places: -6 ~ 0 °C in alpine mountains, 1 ~ 4 °C in guibei, 4 ~ 8 °C in guinan. On the 26th and 27th, the whole district was cloudy to cloudy. The minimum temperature in various places: -1 ~ 3 °C in alpine mountains, 4 ~ 8 °C in guibei, 9 ~ 14 °C in guinan. From the 28th to March 1st, there was scattered light rain on the cloudy days in northern Guizhou and western Guizhou, and the other areas in our region were cloudy to cloudy. The minimum temperature in various places: 2 ~ 7 °C in alpine mountains, 8 ~ 12 °C in northern Guizhou, 12 ~ 15 °C in southern Guizhou.
3. May affect the analysis
It is expected that the meteorological conditions in March will be more favorable for the harvest of sugarcane in most sugarcane areas, the sowing of seedlings and the growth of cane planting in spring (Figure 4), but the minimum temperature in Guangxi before the 26th is still low, and it is still necessary to guard against the adverse effects of frost weather on sugarcane production.
Figure 4 Distribution of meteorological suitability of spring cane planting in Guangxi in the next 10 days
Third, production recommendations
(1) Uncut sugarcane cold-proof and anti-freeze technical measures
1. Adjust the cut-and-go plan. For sugarcane that has been affected and the sugarcane fields and varieties that have been seriously affected in previous years, it is advisable to plan to cut down and enter the factory for pressing as soon as possible to reduce the loss of raw sucrose sugar, especially the low-lying sugar fields, the northern slopes and the No. 22 varieties of Xintai Sugar should be cut down and pressed as soon as possible.
2. Smoke antifreeze. In the time when frost may occur and in the cane area, smoke and antifreeze measures are taken, and smoke piles are set up around the cane field according to local conditions, and the distance between the smoke piles is 10 to 15 meters, and the smoke is burned at night to make the smoke continue until the early morning. General smoke can increase the temperature of the cane field by 1 to 3 ° C to achieve the purpose of antifreeze.
3. Irrigate or spray the cane field. Irrigation or spraying of cane fields in conditional cane areas can increase soil moisture, increase heat capacity and thermal conductivity, cool down slowly at night, play a role in antifreeze, and help photosynthesis and enhance sugarcane vitality. However, the water should be drained one week before harvest.
(2) Cold-proof and anti-freeze technical measures for sugen and newly planted sugarcane
1. For the cane field that has been harvested with overnight roots, before the end of the frost, it is not advisable to open the ridge pine and cover it with a film or cane leaves to avoid freezing the cane buds. After the end of the frost, the root cane should be opened and replanted in time, organic fertilizer or fast-acting fertilizer should be applied, field management should be strengthened, and the germination and seedling growth should be promoted.
2. In autumn and winter, organic fertilizer and phosphorus fertilizer should be applied to improve the temperature of the cane field and the frost resistance of sugarcane.
3. For the water cane land, do a good job of drainage measures.
(3) Others
1. Make a good plan for seed retention. For the sugarcane to be retained, the field block with less damage, the growth point is not necrotic, and there are still green leaves should be selected; if the sugarcane with more serious damage, the seed retention site should be appropriately cut down, mainly the healthy buds in the middle section; for new varieties with a small area and need to accelerate reproduction, depending on the degree of damage, the whole-stemmed sugarcane that still has leaf sheaths in the middle and lower parts can be selected.
2. Adjust the planting structure of varieties and increase the area of cold-resistant sugarcane varieties. At present, the structure of varieties in the cane area is unreasonable, the phenomenon of single variety is serious, and the early-ripening, high-sugar and hardy varieties should be promoted in the cane area with frequent frost damage, the planting area of the hardy varieties should be reduced, and the early, medium and late maturing varieties should be reasonably matched to resist the harm of frost damage.
3. The newly planted cane that has been planted is warmed up in the weather, the seedling emergence rate is less than 50%, and it is recommended to replant; if the seedling rate is higher than 50%, the seedling transplanting or healthy tissue culture seedlings are used to replant in time.
4. Key points of sugarcane disease and pest control technology. (1) Newly planted sugarcane is applied to control borers and underground pests according to the actual situation, such as applying medicinal fertilizer during planting, or sprinkling 3.6% insecticidal double granules 5 to 6 kg / mu, or 2% imidacloprid slow-release granules 2.5 to 3 kg / mu, or 10% killing single · thiaziacidine granules 3 to 4 kg / mu, etc.; or after the cane seeds are arranged, the insecticide is mixed with fertilizer and sprinkled with water 30 kg / mu spraying cane seeds, and then covered with soil cover film, the recommended insecticide has 30% chloranthramide • thiamethiazide suspension agent 40 ~ 50 mL / mu, etc.; or after the cane seed is arranged, the insecticide is mixed with fertilizer or mixed with water 30 kg / mu spray cane seeds, and then the soil cover film is recommended, and the insecticide has 30% chlorantine benzamide · thiamethiazide suspension agent 40 ~ 50 mL / mu, etc.; or after the cane seed is laid out, the insecticide is mixed with fertilizer or mixed with water 30 kg / mu spray cane seeds, and then cover the soil cover film, and the recommended insecticide has 30% chlorantine benzamide · thiamethoxazine suspension agent 40 ~ 50 mL / mu, etc.; or after the cane seed is arranged, the insecticide is mixed with fertilizer or mixed with water 30 kg / mu spray cane seeds, and then covered with the soil cover film, the recommended insecticide has 30% chlorantine benzamide · thiamethiazide suspension agent 40 ~ 50 mL / mu, 40% bromoyl-thiamethoxazine suspension seed coating agent 40~50mL/mu, etc. In the cane fields with serious disease hazards such as smut disease, conditionally, when the sugarcane is planted or the fungicide is drizzled after sowing, the recommended fungicides are 25% pyrocycrazole emulsion 1800 to 2000 times, 25% azoxystrobin emulsion 1200 to 1500 times, 25% propexazole emulsion 800 to 1000 times, 50% carbendazim wettable powder 800 to 1000 times liquid, etc. (2) In the cane area susceptible to cold frost damage should be planted varieties with strong cold resistance, it is recommended to use carbendazim, phenoxymethazole and other fungicides to plant a cover film. Cane seedlings affected by winter planting cane and root cane that have been affected by cold frost damage can be sprayed with micro-fertilizer and phenoxymethanazole and other sterilization to alleviate the harm and restore normal growth according to the hazard situation.