By MURIMI GITARI
Nematodes are the single most significant cause of crop losses worldwide in many crops. There are many different types of plant parasitic nematodes, but they have two features in common; cause directly or indirectly yield reduction or total crop loss, cause significant reduction in crop quality and therefore marketability and value.
Eco spray, a biological control company based in the United Kingdom, working exclusively with Dudutech, their Kenyan Distributor based at Lake Naivasha (www.dudutech.com) have introduced a new product, Nemguard which is based on extract of garlic, which is now registered in Kenya for use by growers on Roses and French Beans.
Garlic (Allium Sativum) contains a wide range of carefully selected organosulfur compounds which show a variety of biological effects including nematicidal, insecticidal, antibacterial and anti fungal activity.
The product was approved for use in Europe through the European Union and its member states have registered it for their own specific crop protection issues. Spain, Italy, Portugal, UK France, and Netherlands are some of the countries that have approved the product for use. It also has registrations in Turkey, Israel and is undergoing registration in New Zealand and Australia.
Speaking to HortiNews, Lee Kaigai who is the Ecospray Regional Manager in East Africa says that Nemguard SC was recently approved for use in Kenya by the Pest Control and Products Board (PCPB).
Mr. Kaigai says that Nemguard has been positioned for sustainable management of parasitic nematodes that damage plant roots. Farmers can now reduce their reliance on existing synthetic more aggressive actives that are becoming less available in the market by opting to use Nemguard which has proved to be environmentally friendly and not harmful to human health. It is a natural product that is low risk and sustainable as it does not harm beneficial organisms in the soil like fungi and bacteria involved in the breakdown of organic matter.
“So far we have conducted commercial trials with flower growers where the problem exists. The approach has been first establishing the nematode threshold through soil sampling and analysis in the lab and we have obtained good control in the field.”
Mr Kaigai says that there are flower farms that are currently using the product and are happy with its performance and we continue to make growers aware of the availability of the product, providing best practice advice on its use to enable them to reap maximum benefit as they position it in their IPM programs
Nematodes are destructive pests that cause yield losses. They feed on roots where they pierce them and take away nutrients and water from the plant. The piercing also enables entry of soil borne diseases and viruses introducing secondary infections. For flowers as an example Yield in terms of the stems per area is reduced while the flush period is extended due to stunting. Quality of stems is also reduced with smaller sized heads and thinner stems.
There are numerous genus of parasitic nematodes however locally Meloidogyne (root knot nematodes) that attacks plant roots causing galling is the most prevalent and widely studied. These are sedentary endoparasites meaning they have part of their life cycle outside the plant root and part inside. Through the cycle once inside the roots the nematodes trigger abnormal multiplication of cells which results to formation of giant cells (galling) where they feed from. Eggs are exuded outside the roots and the infective juvenile has a needle like structure called a stylet that enables entry into roots by piercing. These are some of the distinctive features of this genus that have made it successful as a soil pest.
A keen look at the nematode problem locally will reveal other genus like Heterodera (Potato cyst nematode) whose incidence in Potatoes needs to be given serious attention. Awareness of this problem is now increasing with more experts in the field, availability of diagnostic tools locally and the desire by commercial growers to optimize yields.
Their aim as Ecospray is to suppress the parasitic problem nematodes to allow crop yield and quality expression while ensuring soil health is maintained by not destroying beneficial soil organisms.
Dudutech train farmers on identifying nematodes and advising them on the importance of adopting Integrated Pest Management system (IPM) for sustainability of the environment. This is in regard to combining various strategies in controlling pests through cultural, physical, biological and as a last resort chemical means.
Ecospray is geared towards having a product that is a sustainable and safe option for managing parasitic nematodes problems in approved crops and are looking at other crops so as to expand the usage of the product. .