Paddy herbicide injury causes and treatment

The whole rice growth period , would suffer a variety of grass pest hazards, in order to reduce production losses , had to use pesticides to control pests , but in the course of medication , due to improper use , often resulting in injury , affecting the normal growth of rice , light who retired green leaves yellow , brown spots , banana leaf ; severe slow growth, plant death , causing output to fall. Injury caused yield losses sometimes more than the losses caused by pests is also large, and too much pesticide residue will affect human health.
In recent years, paddy herbicide injury caused by improper use of more and more , threatening the growth of rice , rice and even lead to death . According to recent years of field observations and refer to relevant reports and literature on paddy herbicide injury causes, diagnosis, prevention and remedial analyzed and discussed in order to provide the basis for the control of herbicide injury .

A herbicide injury causes

1.1 pesticides

1.1.1

Physical and chemical properties of pesticides . In general, the pesticide on crops have certain physiological effects , such as oil , powders and the like to plug the pores and cause leaf injury ; copper preparations , preparations such as arsenic , copper sulfate, calcium arsenate , sprayed on plant leaves , so that the agents penetrate the plant tissue and produce injury.

1.1.2

Pesticide quality . Use of poor quality, impurities or deterioration of pesticides , easy to cause injury, such as rice seedling Butachlor used as mixed with more impurities such as alachlor , rice seedlings can cause serious injury. Some improper storage of pesticides , storage for a long time , causing the EC layered , liquid precipitation, powder, wettable powder deliquescence caking , not only directly affect the efficacy , can lead to injury produce .

1.1.3

Mixture. Between pesticide mix properly, can also cause injury. Such as rice administered propanil control barnyardgrass not to hurt rice , because rice contains amide hydrolase biodegradable propanil , but propanil and dimethoate, carbaryl and other pesticides , the rice plants by the amide hydrolase inhibition , causing phytotoxicity to paddy rice .

1.1.4 solution concentration . Dose and the use of pesticides sprayed plants withstand concentrations exceed the standard , will hinder plant growth , resulting in injury and even kill the plant .

1.1.5 spraying times. Re-spray and even spray can also cause injury.

1.1.6 application methods . Application methods have a certain relationship with the injury , hand held sprayer such as rice using Butachlor when foliage spray applicator than the toxic soil mix prone to injury.

1.2 crops

1.2.1

Crop species and varieties. For each pesticide various crops showed different patterns of resistance and sensitivity . Such as rice germ on thiram , carbendazim and other pesticides are resistant , while kitazine sensitive .

1.2.2

Crop growth period . Different growth stages of crops sensitive to insecticides reaction differs greatly . Such as rice Bud Valley , seedling and jointing using MCPA , prone to injury , and in the seedling to tillering stage 4 leaves after spraying MCPA future growth of late , there is strong resistance to rice .

1.2.3 plant parts . Between the various parts of the crop 's susceptibility to insecticides quite different . Generally resistant to strong stem , buds , leaves prone to injury.

1.2.4 crop . Crops can cause debilitating injury . In the rice transplanting process, such as turning green seedlings still in the use of herbicides , but also easy to cause injury.

1.3 Environmental aspects

1.3.1

Temperature . Temperature directly affects the level of pesticide activity is also related to the safety of pesticide on crops . Spraying in high temperature environments ,liquid sprayer because of high activity of pesticides , which led some pesticide phytotoxicity .

1.3.2

Humidity and rainfall . Humidity is too large , too much water can cause injury. Such as rice seedling is not flat, the lower water after sowing, pre-emergence application nitrofen , low-lying valley will dry bud bud seedlings died . Honda initially applied Oxadiazon , if large flooded seedlings, can also cause injury. Similarly , water retention is poor, too little moisture paddy fields , the application of such herbicide molinate , liquid penetrate into the roots of the rice-growing is not safe.