CN105638741A - Bacillus thuringiensis floating sustained-release tablet and preparation method thereof - Google Patents

Abstract

The invention discloses a bacillus thuringiensis floating sustained-release tablet. The bacillus thuringiensis floating sustained-release tablet comprises 25-45% of granulated cork 0.1-1mm in grain size, 15-40% of silicate mineral granules 0.1-1mm in grain size, 5-15% of bacillus thuringiensis israelensis active ingredient powder, 10-30% of latex, 0.1-1% of CMC-Na and 0.1-1% of antiseptic. The bacillus thuringiensis floating sustained-release tablet is capable of floating on the water stably and releasing chemicals in a sustained manner, so that lasting effect time is prolonged remarkably and the number of times of bacillus thuringiensis floating sustained-release tablet throwing is decreased.

Description

A kind of bacillus thuringiensis slow release floating tablet and preparation method thereof

Technical field

The invention belongs to field of biological pesticide, relate to a kind of bacillus thuringiensis slow release floating tablet for water body mosquito control and preparation method thereof.

Background technology

Mosquito is a kind of insect that nature is widely present, and it not only has a strong impact on our life, propagates the medium of multiple disease especially. At present in China, sucking blood and pathophorous mosquito kind can have kind more than 10, the disease of its propagation mainly has malaria, filaricide, epidemic encephalitis type B and dengue fever etc., severely compromises the physical and mental health of the people.

20th century pesticide extensive use, become the technical way of mosquito control, mosquito insecticides most widely used at present is mainly the chemical insecticide of chrysanthemum esters, in view of insect resistance continues development, and pesticide pollution environment is day by day serious, this approach of Biological control is day by day subject to medical insect circle, has the attention of shutting mechanism including World Health Organization (WHO) etc.

Bacillus thuringiensis subsp israelensis (Bti) is a product most in bacillus thuringiensis (Bt) insecticide family with application and development potentiality, its side effect non-toxic to humans, the larva of yellow-fever mosquito and culex there is good killing effect, Bti can kill larvae efficiently, mosquito radix can have effectively been controlled at ppm concentration level, and to people and eco-friendly, have no side effect. It is usually at present and Bti can wet-milling or liquor be applied in the water surface or pools zone, mosquito eradication purpose is reached to kill larvae, because liquor also exists significant unstability, it is difficult to formation scale, can be inconvenient to use by wet-milling, and free settling, efficiency time is short, causes the weak effect of mosquito control.

Summary of the invention

It is an object of the invention to for drawbacks described above, it is provided that a kind of bacillus thuringiensis slow release floating tablet for water body mosquito control and preparation method thereof.

Bacillus thuringiensis slow release floating tablet provided by the invention is grouped into by the one-tenth of following weight proportion:

Preferably, described silicate mine is kaolinite or montmorillonite or asbestos.

Preferably, described preservative is sodium benzoate.

Preparation method provided by the present invention comprises the following steps:

1) by former for bacillus thuringiensis subsp israelensis medicated powder through comminution by gas stream to 200��700 orders, then with granulated cork, silicate mine granule mixing, obtain dry material;

2) CMC-Na is expanded into, with water-soluble, the colloidal sol that weight content is 0.5��2%, then stirs with latex, mix, obtain epoxy glue;

3) dry material is mixed with epoxy glue, stirring, make soft material, then in a mold with 0.1��2Kg/cm²Pressure tabletted, be dried to water content after the demoulding lower than 10%, to obtain final product.

The invention has the beneficial effects as follows:

1) the present invention is to provide one former for Bti medicine and granulated cork, silicate mine granule etc. to be cross-linked with each other, have the tablet of three-dimensional many porous network structures, wherein, granulated cork has reduction density, adsorbs medicine and lure the effects such as mosquito; Silicate mine granule has bigger specific surface area, it is possible to adsorb medicine in large quantities, thus reducing the rate of release of medicine, improves its stability; And latex and CMC-Na form colloidal sol after dissolving in water, colloidal sol protecting film can be formed around tablet, reduce the release of medicine further. The present invention can stably swim on the water surface and continue to discharge lentamente medicine, thus significantly extending efficiency time, reduces dispensing number of times.

2) good stability of the present invention, transport, store, easy to use, environmental protection, add technique simple, environment, economic and social sustainable development had great importance.

Detailed description of the invention

Below in conjunction with specific embodiment, the present invention is described in detail.

Embodiment 1

A kind of bacillus thuringiensis slow release floating tablet, it is made up of the composition of following weight proportion:

Raw material illustrates:

(1) granulated cork: the bark of thick matter is divested outer layer brown colour layer, internal layer is yellowish or the soft tree skin layer of canescence is pulverized through blade type pulverizer, and the granule that sieve takes 0.1��1mm diameter is standby;

(2) kaolinite granule: kaolinite prepares into the cellular thing of lightweight, size-reduced screening through high-temperature calcination technique, and the granule taking 0.1��1mm diameter is standby;

(3) the former medicated powder of bacillus thuringiensis subsp israelensis: being bought by commercially available approach, biological value is more than 6500ITU/mg.

Preparation technology is as follows:

1) by former for bacillus thuringiensis subsp israelensis medicated powder 10Kg through comminution by gas stream to 200��700 orders, then with granulated cork 39Kg, kaolinite granule 25Kg mix, obtain dry material 74Kg;

2) CMC-Na0.5Kg is expanded into, with water-soluble, the colloidal sol that weight content is 1%, then stirs with latex 25Kg, mix, obtain epoxy glue 75Kg;

3) dry material is mixed with epoxy glue, stirring, make soft material, then use 1.2Kg/cm in a mold²Pressure tabletted, every nearly weighs 20g, after the demoulding below 70 DEG C heat-wind circulate drying to water content lower than 10%, to obtain final product.

Embodiment 2

A kind of bacillus thuringiensis slow release floating tablet, it is grouped into by the one-tenth of following weight proportion:

Preparation technology is as follows:

1) by former for bacillus thuringiensis subsp israelensis medicated powder 5Kg through comminution by gas stream to 200��700 orders, then with granulated cork 45Kg, montmorillonite granule 18Kg mix, obtain dry material 68Kg;

2) CMC-Na1Kg is expanded into, with water-soluble, the colloidal sol that weight content is 2%, then stirs with latex 30Kg, mix, obtain epoxy glue 80Kg;

3) dry material is mixed with epoxy glue, stirring, make soft material, then use 0.5Kg/cm in a mold²Pressure tabletted, be dried to water content after the demoulding lower than 10%, to obtain final product.

Embodiment 3

A kind of bacillus thuringiensis slow release floating tablet, it is grouped into by the one-tenth of following weight proportion:

Preparation technology is as follows:

1) by former for bacillus thuringiensis subsp israelensis medicated powder 15Kg through comminution by gas stream to 200��700 orders, then with granulated cork 25Kg, asbestos particles 40Kg mix, obtain dry material 80Kg;

2) CMC-Na0.1Kg is expanded into, with water-soluble, the colloidal sol that weight content is 0.5%, then stirs with latex 19.8Kg, mix, obtain epoxy glue 40Kg;

3) dry material is mixed with epoxy glue, stirring, make soft material, then use 2Kg/cm in a mold²Pressure tabletted, be dried to water content after the demoulding lower than 10%, to obtain final product.

For detecting the mosquito killing effect of the present invention, we 4 be provided with 1 ton of air-vent airtight add water container puts into respectively artificial breeding 2 age wriggler 100, it is separately added into floating tablet and the former medicated powder of bacillus thuringiensis subsp israelensis of the embodiment 1��3 of same dose simultaneously, within every 5 days, put into again 2 age wriggler 100 check the borer population alive of last time and dead borer population, calculating mortality rate, result is shown in following table:

The insecticidal effect of table 1 embodiment 1��3 compares

	Embodiment 1	Embodiment 2	Embodiment 3	The former medicated powder of Bti
					Throw worm mortality rate (%) 1st time	85	80	88	97
Throw worm mortality rate (%) 2nd time	95	78	75	58
					Throw worm mortality rate (%) 3rd time	94	74	65	12
The 4th throws worm mortality rate (%)	90	69	60	1
					The 5th throws worm mortality rate (%)	85	66	59	1
Throw worm mortality rate (%) 6th time	80	60	55	0

Can be seen that from above result of the test, the embodiment of the present invention 1��3 can significantly extend efficiency time, killing rate during the 6th throwing worm (i.e. dispensing 30 days) is still up to 55��80%, and common former medicated powder killing rate when throwing worm (i.e. dispensing 10 days) the 2nd time drops to less than 60%, it was demonstrated that the present invention has good slow release effect. Meanwhile, the killing rate of embodiment 1 and holding effect effect are best.

Claims (4)

1. a bacillus thuringiensis slow release floating tablet, it is characterised in that be grouped into by the one-tenth of following weight proportion:

2. bacillus thuringiensis slow release floating tablet as claimed in claim 1, it is characterised in that described silicate mine is kaolinite or montmorillonite or asbestos.

3. bacillus thuringiensis slow release floating tablet as claimed in claim 1, it is characterised in that described preservative is sodium benzoate.

4. the preparation method of bacillus thuringiensis slow release floating tablet as described in claims 1 to 3 any one, it is characterised in that comprise the following steps:

1) by former for bacillus thuringiensis subsp israelensis medicated powder through comminution by gas stream to 200��700 orders, then with granulated cork, silicate mine granule mixing, obtain dry material;

2) CMC-Na is expanded into, with water-soluble, the colloidal sol that weight content is 0.5��2%, then stirs with latex, mix, obtain epoxy glue;

3) dry material is mixed with epoxy glue, stirring, make soft material, then in a mold with 0.1��2Kg/cm²Pressure tabletted, be dried to water content after the demoulding lower than 10%, to obtain final product.