Trinidad and Tobago Country Coordinator Shamela Rambadan sent the photo below of a Soursop (Annona muricata) plant brought into a clinic in County Victoria in Trinidad and Tobago by farmer Ramesh Ramnanan last month. The symptoms described included yellowed, distorted leaves and visible insects on the leaves, as seen in the photo. Plant health officer Zobida Mohammed diagnosed the symptoms to be caused by mealybugs and scale insects and recommended that the farmer used a suitable insecticide on the crop to avoid further damage.
Researchers at Swansea University have found a strain of fungi that could replace harmful pesticides in the control of the European crane fly (Tipula paludosa). The effects of 17 strains of entomopathogenic fungi, chlorpyrifos-based pesticides and a nematode worm were compared. The pesticides and fungal strain V1005 Metarhizium robertsii were both found to be 100% effective at controlling crane fly larvae, which are pests to many crop and tree species. The larvae, known as ‘leatherjackets’, feed on cereals, cabbages and lettuces, as well as young tree saplings, resulting in millions of pounds of damage every year in Europe and North America. Continue reading
The Mexican Fruit Fly Anastrepha ludens is the most important native fruit fly pest of citrus in America and also infests other economically important crops such as peaches, peppers and mangoes. In cooperation with the U.S. Department of Agriculture, Mexico has developed a Sterile Insect Technique (SIT) method which involves exposing huge quantities of male fruit flies to irradiation before releasing them en masse to mate with wild female flies. The male flies are exposed to enough radiation to sterilise them, so that mating with wild females results in the production of non-viable eggs. Over time repeated releases of large quantities of sterilised male flies causes the target pest population to collapse. The use of the SIT applied as part of an area-wide integrated pest management approach provides an environmentally safe and species-specific method to suppress, and in some cases eradicate insects of agricultural, veterinary and medical importance worldwide. The success of the SIT in effectively controlling target pest insect populations requires males to be able to successfully compete against wild unsterilized males to mate with females. Recent developments to improve SIT program effectiveness have been discovered by scientists from the Agricultural Research Service who found that the use of methoprene, an analogue of an insect hormone, and additional protein hydrolysate in the fruit fly diet helped to make sterilised males more “macho” by increasing their competitiveness in the wild, therefore making them more attractive as a mate to females.
It’s good news for the savanna ecosystem that the elephant population of East Africa has increased in recent years, but bad news for farmers whose crops are being devoured by these giant pests. Wildlife services’ successful anti-poaching campaigns and an increased designation of land to national parks has helped elephant population numbers to recover. However, with the concurrent expansion of farmland, there are now more frequent encounters between man and beast. Continue reading
It takes a large combined effort to successfully eradicate a plant pest. The Guam Coconut Rhinoceros Beetle Eradication Project has finally found a technique that could bring them their own eradication success story. The coconut rhinoceros beetle (Oryctes rhinoceros) was first discovered in Guam on 11th September 2007. Over the past five years it has caused severe damage to coconut palms, although its initial spread was slowed by the quick reactions of the government. It is now present in many parts of the island and, as coconuts are an important economic commodity for the US territory, is high priority for removal. Continue reading
The Society for the Protection of Nature in Israel is encouraging farmers to use barn owls (Tyto alba) to control rodent pests on their crops. They aim to attract barn owls by constructing nest boxes; so far 2,000 have been distributed to farmers. As barn owls only hunt at night, day-hunting kestrels are also being provided for to ensure a more effective rodent-targetting system. Although it has taken a while to persuade farmers in neighbouring Jordan to take up the use of barn owls in their fields, success has also been had controlling rodent populations there.
It isn’t just farmers from the Middle East that have found birds of prey to be beneficial when dealing with rodent pests. All around the world, farmers have found that this natural solution can be cheaper and less harmful to the environment than using poisons or traps. Here are some case studies of using birds of prey in agriculture: Continue reading
Scientists in the UK and Uganda are developing a genetically modified (GM) variety of banana that is resistant to nematode worms, which account for a high percentage of banana crop losses in Africa. It is estimated that the losses of crops due to nematodes amounts to $125 billion a year. Currently, nematodes are controlled using pesticides that can be toxic to humans and other organisms. The project, run by the Africa College at the University of Leeds and funded by BBSRC and DfID, has provided training to African-based scientists and aims to conduct trials of the banana plants in several African countries. Continue reading