CN103636630A - Polyoxins-containing sterilization composition - Google Patents

Abstract

The invention belongs to the technical field of pesticides, and relates to a polyoxin-containing sterilization composition, which is characterized by containing two active ingredients, namely natamycin and polyoxins. The composition can be prepared into a suspending agent, is used for preventing and controlling cucumber downy mildew, has remarkable synergistic effects, and is safe and harmless to crops.

Description

Bactericidal composition containing polyoxin

Technical field

The invention belongs to technical field of pesticide, contain specifically the bactericidal composition with synergistic effect of natamycin and polyoxin.

Background technology

Natamycin (Natamycin) is a kind of natural antifungal compound being produced by streptomycete fermentation, belong to polyene macrolides, rely on the sterol compound effect on its lactonic ring structure and fungal cell membrane, form antibiotic-sterol compound, thereby destroy the structure of the cytoplasma membrane of fungi; The hydrophilic segment of macrocyclic lactone (many alcohol moieties) forms water hole on film, damaging cells membrane permeability, and then cause that the materials such as amino acid in bacterium, electrolyte ooze out and cause thalline dead.This composition can effectively suppress various moulds, saccharomycetic growth, and generation that again can Antifungi toxin can be widely used in the fresh-keeping and antifungal therapy of food antiseptic.

Polyoxin (polyoxin) is the metabolite that streptomyces aureus produces, and belongs to broad-spectrum antibiotics series bactericidal agent.In having preferably, inhale conduction.Its mechanism of action is to disturb the chitinous biosynthesis of germ cell wall, makes somatic cells wall can not carry out biosynthesis and causes germ dead.This composition also has the effect that germ produces spore and scab expansion that suppresses.This composition is mainly used in preventing and treating alternaria leaf spot of apple, ring spot, Pear black spot, grape grey mould, strawberry, cucumber, the powdery mildew of muskmelon, downy mildew, black fleck disease of ginseng, Alternaria alternate, the ten various crop diseases such as the banded sclerotial blight of paddy rice.

Cucumber downy mildew (Rhizoctorzia solani) claims again " horse race is dry ", " cured leaf ", is that one of the most general, harm is the most serious disease occurs on green house cucumber.This disease morbidity scope is wide, and all there is generation in the area of every plantation cucumber; And all can occur the time of infertility cucumber, when developmental condition is suitable, its development speed is very fast, 3～5d can make whole plant leaf (except several pieces tender leafs of top and indivedual Lao Ye) withered and yellow.The general popular time can the underproduction 20%～30%, and when serious, loss reaches more than 50% even whole canopy chamber and gets nowhere, and has a strong impact on vegetable grower and takes in.

Summary of the invention

The object of this invention is to provide a kind of bactericidal composition with synergistic effect and safety and environmental protection, realize the object that improves drug effect, reduces pollution, reduces costs.Be specifically related to the bactericidal composition of natamycin and polyoxin.

Utilizing above-mentioned bactericidal composition, be equipped with the known auxiliary agent of those skilled in that art, with the known method of those skilled in that art, make formulation of the present invention, is suspending agent.

In above-mentioned bactericidal composition, the proportion of natamycin and polyoxin is 1:50-50:1.

Above-mentioned bactericidal composition has following characteristics: the 1. advanced environmental protection of formulation, and environmental pollution is little, does not add organic principle in preparation; 2. bactericidal action is strong, is difficult for developing immunity to drugs; 3. two kinds of compositions are composite, have synergistic effect; 4. twenty percent divide between without cross resistance.

Embodiment

For determining natamycin and two kinds of composite synergistic effects of active ingredient of polyoxin, first applicant uses these two kinds of compositions to carry out indoor biometrics test, and test method and result are as follows:

First analyzed after the effect feature of two kinds of active ingredients, we are decided to be Cuba artificial downy mildew (Pseudoperonospora cubensis) by the raw object of surveying, this Pseudomonas Mastigomycotina fungi, germ is live body obligatory parasitism fungi, seed does not carry disease germs, germ is mainly propagated by air-flow, from Stoma of Leaves, invades.This sick rate of propagation is very fast, and someone is referred to as " horse race is dry ", once there be primary infection focus, only needs the expansion of 3～4 times to infect again, can lead to terrible disaster, and the key of therefore preventing and treating this disease is to find as early as possible, early control.

The test method of indoor biometrics: adopt growth rate method to measure the inhibitory action of medicament to the growth of cucumber downy mildew mycelia.On the basis of preliminary experiment, from each medicament, germ mycelial growth inhibition rate is reached and within the scope of 10%-90%, designs 5 concentration, first the former medicine of 90% natamycin and the former medicine of 90% polyoxin be take methyl alcohol as the liquid that solvent is made into series concentration standby, then by liquid in 1% ratio join melt and the PDA medium of cool to room temperature in, after fully shaking up, pour that in the culture dish (Φ 90mm) of sterilizing, to make band medicine dull and stereotyped into, every processing repeats for four times, to add the blank that is treated to of sterile water; Card punch (Φ 5mm) picking bacterium of downy mildew of cucumber bacterium cake with sterilizing, mycelia faces down aseptic inoculation in the central authorities with medicine flat board, be inverted in interior cultivation of constant incubator of 25 ℃, after cultivation 6d, adopt right-angled intersection method to measure colony diameter, calculate the EC of each medicament to pathogen ₅₀, and calculate according to the following equation toxicity index, the virulence of more different medicaments and bacteriostasis.Above-mentioned raw survey experiment former medicine used and reagent are all bought from other producers.

The co-toxicity of mixture preparation adopts the abundant co-toxicity coefficient method representation of Sun Yun:

The theoretical toxicity index TTI=∑ of mixture preparation (the toxicity index ATI of certain medicine * percentage of this pharmaceutically active ingredient in mixture).

It is synergistic effect that co-toxicity coefficient CTC is greater than at 120 o'clock, and being less than at 80 o'clock is antagonism, is addition in the time of between 80-120.

Indoor biometrics test data sees the following form:

Table 1 natamycin, polyoxin and the measurement result of different proportioning to cucumber downy mildew co-toxicity coefficient thereof

Analyze above-mentioned data, can obviously find out when natamycin and polyoxin are composite in varing proportions, the co-toxicity coefficient (CTC) of formula is all greater than 120, the prevention and control capability of cucumber downy mildew is had to the synergistic effect of different proportion, wherein natamycin and polyoxin are being that proportioning four is the most remarkable to the synergy between proportioning six between 1:5-5:1.

By indoor biometrics, test and determine natamycin and two kinds of active ingredients of polyoxin are composite can good synergistic effect, below by instantiation in order to further describe the present invention, but the present invention absolutely not only only limits to following these embodiment.In formula, percentage is all weight percentage, and the former medicine using and auxiliary agent are other producers and buy.

Formulation examples is as follows:

Example one, 10.2% natamycin polyoxin suspending agent

Example two, 3.1% natamycin polyoxin suspending agent

Example three, 11% natamycin polyoxin suspending agent

Example four, 6% natamycin polyoxin suspending agent

Example five, 10% natamycin polyoxin suspending agent

Example six, 12% natamycin polyoxin suspending agent

Example seven, 3.3% natamycin polyoxin suspending agent

Example eight, 6.2% natamycin polyoxin suspending agent

Example nine, 10.2% natamycin polyoxin suspending agent

Select above example to prevent and treat the field trial of cucumber downy mildew, determine the effect of formula control cucumber downy mildew; Simultaneously by the Contrast on effect with natamycin and polyoxin single dose, verify the synergistic effect after composite.Concrete test method data are as follows:

The field control effectiveness test of 6% natamycin polyoxin suspending agent and other preparation control cucumber downy mildew.Test site is Yangling Shaanxi, and the time is on October 13rd, 2012, executes first pass medicine, executes second time medicine on October 20.Test each and process three repetitions, community randomized arrangement, each community area is 20m2, adopt back-pack electric compression sprayer, dispenser was sunny calm the same day, and the planting habit of all communities is all identical with local planting habit, record the dispenser same day and the synoptic data of a week thereafter, specific as follows:

Table 2 duration of test meteorological data

Investigation method:

8 points of each community random searching, each some investigation 2 strain cucumber, records total number of sheets, blade disease index.

Investigation number of times:

Before dispenser for the first time on October 13 in 2012, carry out the investigation of state of an illness radix, medicine will be investigated 7 days day after tomorrow for the second time for the first time, within after medicine 6 days for the second time, investigate for the third time, will investigate altogether 3 times.

The grade scale of disease index:

0 grade: without scab;

1 grade: lesion area accounts for below 5% of whole leaf area;

3 grades: lesion area accounts for 6%～10% of whole leaf area;

5 grades: lesion area accounts for 11%～25% of whole leaf area;

7 grades: lesion area accounts for 26%～50% of whole leaf area;

9 grades: lesion area accounts for the more than 51% of whole leaf area.

Table 36% natamycin polyoxin suspending agent and the preventive effect of different medicament to cucumber downy mildew

From above-mentioned data, can find out, natamycin and polyoxin complex preparation after medicine 7 days preventive effects all over 77%, and natamycin single dose 7 days preventive effects after medicine are 51.04%, the preventive effect of polyoxin single dose is 53.01%, compare natamycin and polyoxin single dose, complex preparation synergistic effect is remarkable.And after medicine for the second time 6 days, all complex preparations have all surpassed 85% to the preventive effect of cucumber downy mildew, and the lasting period of composite rear preparation extends, more lasting to the control efficiency of cucumber downy mildew.Improve drug effect, alleviate peasant's financial resources, material resources, have very high practicality.

Claims (3)

1. containing the bactericidal composition of polyoxin, it is characterized in that: active component is comprised of natamycin and polyoxin, the weight ratio of described natamycin and polyoxin is 1:50～50:1.

2. bactericidal composition according to claim 1, is characterized in that: by active ingredient and auxiliary material, make suspending agent.

3. according to claim 1 or bactericidal composition claimed in claim 2, it is characterized in that: for preventing and treating cucumber downy mildew.