Waterlogging And Remedial Measures In Cotton Fields In The Middle Reaches Of The Yangtze River

Since mid May, a high-intensity, long time heavy rainfall has struck the southern region, affecting cotton production, causing cotton fields to suffer different degrees of waterlogging and adverse effects on cotton production.

The national public welfare industry research project group investigated the disaster situation in several provinces of Jiangxi, Hunan, Hubei and Anhui, and put forward management measures for decision-making.

First, cotton field disaster situation

From May 13th to June 25th, 60% cotton fields were affected by heavy rainfall in Jiangxi Province, with an area of 500 thousand mu, of which one or two, three cotton fields accounted for 15%, 40% and 45% respectively. The harvest area was 100 thousand mu, and the cotton fields were converted to soybean, sesame, mung bean and corn crops.

Since the middle of May, 5 large scale precipitation processes have occurred in Hubei since May: May, 12-13, 15-18, 21-22, 26-28, June, 7-8 and 23-24 days.

According to monitoring, Hubei province in 2010 cotton planting area of 7 million 500 thousand acres, waterlogging area of nearly 40%, less harvest area.

Since June, heavy rain has been widespread in Hunan, especially in southern Hunan.

A small area of waterlogging disaster occurred in cotton fields. About 8000 acres of cotton fields in Lixian were covered with stains, of which more than 1000 mu were replanted to rice and the rest were less damaged.

There are basically no disasters along the Yangtze River in Anhui.

Two. Adverse effects of Waterlogging on cotton

5 the continuous rainfall from mid June to the end of June resulted in low temperature and less illumination. The temperature was lower than 2 in the same period of the same period. The accumulated temperature in the growth period was less than 100 degrees, and the sunshine hours in most areas were less than 20 hours.

On the 13-22 day of May, the temperature in the central and southern part of the Jianghan Plain was 9 days below 20 degrees Celsius. In the early June, there was a "cold of mango" (the average daily temperature was 3 days below 22 degrees Celsius or one day below 20 degrees Celsius).

First, the growth period is delayed, the growth is weak and uneven.

Continuous rainfall leads to excessive soil moisture in the field, which is not conducive to growth. In the long term, low temperature and poor illumination result in insufficient photosynthesis and little accumulation of dry matter, resulting in delayed growth and slow growth.

At present, about 60% cotton seedlings in Hunan do not reach the bud stage, which is more than 15 days later than in previous years.

The growth of cotton seedlings was irregular, and there were 3~4 true leaves / plants and 20cm height difference in the same hillock cottons.

Continuous rainfall also delayed the pplanting of cotton seedlings.

By June 24th, there were 4~5 shoots / shoots of seedlings and three branches of seedlings in the middle reaches of the Yangtze River. There was no fruit branch. The growth time of late seedling and weak seedling was more than 20 days, and the proportion of three seedlings was more than two percent.

The two is pests and weeds and waterlogging.

On the one hand, the climate of "high temperature and high humidity" leads to the "two wilt" disease which occurs early and is spreading.

Field investigation showed that the incidence of cotton in Hubei province was 7.9% to 2.05%, the disease index was 4.6 to 22.8, and the serious seedling mortality rate was about 10%.

In southern Lixian, Hanshou, Nanxian and other places, the "two wilt" disease is serious. Some of the serious regional incidence rates in Lixian are about 20%, and the incidence is relatively mild.

The three is the coming of the rainy season. The cotton production situation is facing new challenges.

Affected by the southwestern warm and humid airflow of the subtropical high and the cold air in the north, the strong rainfall belt in the early part of the Southern China area will be lifted to the Yangtze Huaihe River Valley. Hubei province has officially entered the Meiyu period since June 21st. On the 21-23 th, there was a strong rain process in the whole province, and there were 2 precipitation processes at the end of the month.

On the 26-27 day, there was a moderate rainfall process in most parts of the province. There was another rainfall process after 30 days. According to the meteorological department, the weather during the rainy season may be dominated by process rainfall. Most of the counties and cities are close to the average annual value. Therefore, in the coming period, we need to stick to the flood prevention and drought relief. On the one hand, we should pay attention to preventing waterlogging caused by heavy rainfall. On the other hand, we should also pay attention to the proper water storage and water conservation work to prevent the drought caused by less rainfall.

Three, remedial measures for waterlogging.

at present

1. Bury the lodging cotton plant, and wash seedlings and ditching and drain.

2, clear up and break up.

Grasp the fine weather, weed in time, ploughing stubble, thoroughly eliminate the hardwood and harden, and provide good environmental conditions for cotton growth, especially the oil stubble cotton field. At present, the seeds have sprouted and sprout and should be removed as soon as possible.

At the same time, we should clean up the trenches of the waist, the trenches and the surrounding trenches, so as to prevent the occurrence of waterlogging after entering the plum garden.

3, try to promote Lei Fei to build a scaffolding.

In the middle of June, combined with medium tillage and loosening soil, the fertilizer should be combined with quick effect and slow effect. The 30 kg compound fertilizer +10 kg urea +10 kg potassium fertilizer was applied.

4. Ridging and soil to prevent lodging.

Attention should be paid to ridging and cultivation. When the density is low and the interlining ability of cotton plants becomes weaker, it will help to prevent lodging and prevent premature senescence, and also conducive to field drainage and irrigation.

5, strengthen pest control.

At present, bug bug, spider mite and aphid.

The "two wilt" disease has become a major trend in some areas. It is necessary to strengthen the drainage and drainage in the field to reduce the waterlogging damage.

6, classification guidance, grasping and adjusting.

For this year's complicated seedling situation, we should classify and guide, and do well in adjusting the seedlings.

Especially when the plum rains are coming, the cotton fields with normal buds and normal growth should be treated with TAC (or vitamin C) before they enter the plum fields, which can prevent the growth and fall off and promote the growth of the plants.

We should promote three kinds of weak seedlings, but we should promote growth under control.