Expert Blames Vegetable Farmers For Using Banned Pesticides

Dr. Okolle N. Justin, research entomologist with IRAD Ekona, Chief of Antenna for the African Research Centre on Bananas & Plantains (CARBAP) for the Southwest Region, says sustainable crop production can be attained if farmers desist from the abusive use of pesticides. In the following interview, he also discusses the recent findings on crop protection (especially pesticides) on vegetable cultivation, challenges and prospects and advises vegetable farmers on how to safely use pesticides.
What’s new on your research desk?
I’ve been working so much on entomological research, which studies insects, and more especially focusing on agric-entomology. As an agric-entomologist, I have been carrying out lots of research on the biology and ecology of crop pests, farmer’s perception on pests/protection practices, evaluating safer methods of applying some of the common pesticides that they have been using, especially for bananas and plantains, beans, sweet potatoes and vegetables. I have been looking at the life and status of emerging pests on the aforementioned crops.
What are some of these pesticides and their effects?
Vegetables, beans, sweet potatoes, bananas and plantains are some of Cameroon’s widely cultivated and consumed crops by agro-industries and even resource-poor small holder farmers. As far as the crops are concerned, the pesticides used vary with respect to the nature of the farm (whether it is a small farm or a large industrial corporation like CDC, PHP, SOCAPALM, HERAKLES FARMS, PAMOL), the cost, and availability. But commonly we have pesticides like Mocap® (ethoprophos); Counter® (Terbuphos), Dursban® (Chlorpyriphos), Plantima® (imidacloprid), Regent® (Fipronil)Actara® (thiametoxam), Cypercal® (cypermethrine). There are so many registered pesticides but these are the few that are commonly used in agro-industrial plantations and small holders’ farms. The effects of pesticides depend on the group (organochlorines, organophosphates, carbamates, neonicotynoids, phenyl pyrazoles, entomopathogens, etc). Generally, the first three groups are very dangerous; organochlorines are very persistent and accumulate in animal fat including human; organophosphates and carbamates seriously affect the nervous system/brain of animals. Generally, effects of pesticides include development of cancer, some can result to infertility of animals, deformities of newborn babies, diarrhoea, vomiting, skin burns/irritations, eye problems, killing of aquatic organisms, contamination of honey, and driving away/killing insects that pollinate our crops.
Tell us about your research findings on pesticides on vegetables?
Well, on vegetables, we have done so much work. A typical and more recent work we did in partnership with World Vegetable Centre was a survey in three different agro-ecological zones in Cameroon. In this survey, focus was to investigate the different vegetable pests that were present there, what type of pesticide or crop protection practices that are used on these vegetables and lastly, to examine whether the pesticides or crop protection practices are good or bad. It is worth noting that with vegetables, the practices are different from plantation crops like bananas, oil palm and cocoa. We found out that the pesticides are abusively used; either farmers over-use them (apply twice or thrice per week in the absence or presence of pests) or use them at wrong times (1-2 days before harvesting) or use even the ones that have been banned by government or internationally. In Cameroon, the following insecticides (insect killer chemicals) have been banned: malathion, methyl-parathion, carbosulfan, most organochlorines (dieldrin, lindane), and recently (July, 2013), carbofuran was banned. Most of these banned insecticides are considered or categorized by WHO as Class 1a (extremely dangerous). Surprisingly, farmers still use pesticides that have been banned and they even use it unsustainably in a way that increases their risk or exposure to these hazardous chemicals. Therefore, if vegetable farmers can know what rightful chemical to use and at what time, it will drastically increase vegetables production in the country and sustain livelihoods. In addition, we have found out that more than 50% of vegetable farmers in rural areas use empty pesticide containers to store drinking water or oil palm
What measures do you think farmers should implement, based on your research, to guarantee improved vegetable production?
First, they need to be trained on the identification of pests and their management practices as well as on effective use of pesticides/safety measures. Second, they should endeavour to know insecticides registered for vegetables and learn to use these. Third, vegetables should be harvested at least two weeks after application of pesticides. Fourth, find out from agriculture officers or researchers, pesticides that have been banned or not registered and avoid their use. Fifth, completely avoid using empty containers of pesticides to store drinking water or foodstuff as well as avoid rinsing pesticide containers in streams/rivers. Farmers should note here that the environmental law of the country and the phytosanitary law No. 003/2003 of 21st April 2003 provide that those who use banned pesticides and those who knowingly or unknowingly contaminate the environment with such hazardous chemicals can be fined and jailed by the competent authorities.
What are some the approved pesticides which farmers can use to increase their yields?
There are so many pesticides (fungicides, insecticides, nematicides, herbicides, avicides and plant growth regulators) registered in Cameroon. Farmers should consult agriculture officers or pesticide vendors or researchers to get the list of pesticides registered for vegetables.  Otherwise, when buying from pesticide vendors, they should read the labels and they will see those registered for specific vegetables and even specific pests. My recommendation is that pesticides should be used as last resort (this is where Integrated Pest Management comes in) and only when pests seem to be reaching levels where they can cause economic damage.
Briefly tell us the challenges you encountered carrying out this research?
It was a very daunting task but I just love research- I loved the work and I just did it, with or without any monetary benefits. Getting results or discovering something, makes me happy and more so if the result or discovery is used to develop policies and/or technologies that will ultimately improve lives.
*Dr. Okolle is also a lecturer at the University of Buea and a consultant to National/Regional/International Organisations.
Interview by Ambele Eric