Many farmers reflected that the effect of abamectin preventing root-knot nematode is not obviously, some farmers even said there is no effect. But studies found that abamectin has a strong driving effect on root-knot nematodes, ectoparasites and other arthropods. Why farmers were reflected no effects?
By communicating with farmers, researchers found that the bad effects of abamectin is related to their use methods. Many farmers think that it is very troublesome to spray abamectin in plant roots, so that the effect of filling abamectin as water into the field to control root-knot nematodes must be greatly reduced. Because abamectin only in the use multiples of 1500-2500 times can be ensured its effectiveness. In other words, while filling with water, they should ensure that each cubic meter of water plus about one catty abamectin, such a large amount, how many farmers can do it? However, if less than this concentration, abamectin is difficult to fully play its role, this is the reason that farmers reflected abamectin has bad effect on controlling vegetable root-knot nematode.
It is understood that more than abamectin, there are lots of pesticides (mostly used to spray the plant roots) were washed out with water, actually, it both waste pesticides and with poor effect. Because filling pesticides with water, the pesticides concentrations are difficult to control. It should be aware that pesticide application has optimal concentration range. Filling pesticides with water, the water amount is difficult to control, filled how many pesticides is also difficult to calculate, so that farmers can only be sprayed with an approximate concentration range, once the concentration less than optimal concentration range, the effect is difficult to guarantee.
Furthermore, pesticide spraying the roots is cost higher. A moderate amount of water watering, the water consumption is about 20 tons per acre, if the effective concentration of drugs is 500 times, then it needs 40kg pesticides; if it is 2000 times, it also requires 10kg, then the cost of buying pesticides is not a small figure.
Also, filling pesticides with water will aggravate the problem of pesticide residues in soil. If perennial filling pesticides, the pesticide residues in soil will be excessive, then the microbial balance will be broken, the harm will exist for a long time, the potential problems will also difficult to be estimated.
In this regard, the researchers advise farmers: while using pesticides must be strictly in accordance with the operating instructions, as with abamectin control root knot nematode, is best to use the method of collaborating with chitin filling every plant root, spraying in the vegetation period, with 1000-1500 times fluid filling root, each plant filling 250ml liquid. It's a way to guarantee its concentration, and without wastage.
Used of 1.8% abamectin missible oil. Control root knot nematode should use 1 to 1.5ml drugs per square metre before cultivation, diluted 2000 to 3000 folds, uniformly and comprehensively sprayed the soil surface, then immediately rake into 15-20cm topsoil, seeding or planting after stirring well. As the test and production application indicated, the control effect of 1.8% abamectin missible oil against root knot nematode is up to 65-88%. But in some places, through many years of continuous use, the defensive efficiency was declined, it should work with other soil disinfection technology or used interchangeably. In addition, there are many abamectin mixtures on the current pesticide market, the active ingredients to control root-knot nematodes in these mixed pesticides are very low, surveys found that some abamectin suppliers provided poor effective drugs.
Article source:http://www.cospcn.com
