News and knowhow for farmers

Biological pest controls organically cut 50% in vegetable losses


Ve­get­able farm­ers, who lose up to 50 per cent of their har­vest to spider mites, can wipe out the pest using its bio­lo­gical enemy and re­l­at­ive, Real IPM Phyto­sei­ulus.

Phyto­sei­ulus  per­similis, is a mite that feeds on all stages of the spider mites, there­fore, an ap­pro­pri­ate and sus­tain­able ap­proach to deal­ing with the pest without in­ter­fer­ing with the en­vir­on­ment, Isaac Guda, a Real IPM Kenya eco­lo­gical and ag­ro­nom­ical ex­pert said.

“One phyto­sei­ulus feeds on at least five adults and 10 eggs per day. In two to three days after ap­plic­a­tion, a farmer would start see­ing the res­ults,” Guda said.

After ap­plic­a­tion, the pred­at­ory mites quickly re­pro­duce to col­on­ise the leaf, there­fore, of­fer­ing con­tinu­ous crop pro­tec­tion by pred­a­tion.

After reach­ing the eco­nomic threshold, the losses are dev­ast­at­ing and hardly re­vers­ible.

Ac­cord­ing to a study pub­lished on the Re­search Gate, an on­line schol­arly re­source centre, mites have been doc­u­mented to cause more than half losses of to­mato yields.

By the sixth, ninth, and 12th week of spider mite in­fest­a­tion, yields pro­duc­tion re­duces by 0.233kg, 0.689kg and 1.624kg re­spect­ively per to­mato stem.

Apart from mint­ing out the nu­tri­ents from the leaves of crops such as pep­per, cap­sicum, to­ma­toes, black night shade, among oth­ers, the spider mites cause yel­low­ing of the leaves, there­fore, re­du­cing pho­to­syn­thesis rate.

“Heavy in­fest­a­tion will dis­col­our the leaves be­sides caus­ing curl­ing. Leaf curl­ing re­duces the sur­face area for pho­to­syn­thesis. Yel­low­ing of leaves also sig­nals a drop in the chloro­phyll, which is re­spons­ible for food man­u­fac­tur­ing in crops,” the ex­pert said.

READ ALSO: ICIPE: Man­agu ‘kills’ crop mites

READ ALSO: Spider with ap­pet­ite for mos­qui­toes guides war on mal­aria

READ ALSO: Weaver ants clear crops of pests in minutes

Al­though the spider mites are tiny to see, form­a­tion of webs among the leaves and crops should sig­nal a farmer that the pests are quickly mul­tiply­ing.

They mites hang on the webs, which are blown by air cur­rents, there­fore, swinging them to the next leaf or plant, Guda said, adding that at this point loses of up to 90 per cent can be re­gistered.

Un­like chem­ic­als, which kill the pests on the spot on shortly after ap­plic­a­tion, bio­lo­gical solu­tions are slow but more ef­fect­ive in the long run.  For that reason, Guda said, a farmer should not wait for heavy in­fest­a­tion to apply the rem­edy.

With this and other in­teg­rated pest man­age­ment ap­proaches, chem­ical residues are lim­ited.

Real IPM is an in­ter­na­tional or­gan­isa­tion cov­er­ing more than 25 coun­tries glob­ally. Kenyan of­fices and demon­stra­tion farm is in the out­skirts of Thika, Kimbu County.

It can be con­tac­ted on +254725806086.

Get our news into your email inbox every week

We don’t spam! Read our privacy policy for more info.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top