By Anu Veijalainen, CABI. Reblogged from CABI Hand-picked blog.
Yesterday I cherished the start of spring in England by attending an event devoted to pollinators and pollination at the University of Reading. Most presentations at this meeting organised by the Royal Entomological Society were understandably about bees, but we also heard a few talks highlighting the importance of other pollinator groups.
For about five years now the media has been broadcasting alarming news about declining bee populations especially in Europe and North America. While the amounting evidence points to neonicotinoid insecticides being a major cause for the decline, I learnt yesterday that the situation is actually rather complex, other stressors are also involved, and scientists are still eagerly trying to form a complete understanding of the issue.
Example of Ecological engineering in Vietnam (Photo credit: Dr HV Chien)
The rice ecosystems are inhabited by more than 100 species of insects. Twenty of them can cause potential economic losses. With the change in the climatic factors and modern cultural practices adopted for production a drastic change has been caused in the pest scenario in the recent past. Besides stem borer, gall midge, brown plant hopper and green leafhopper which were the major problems in past, several other relatively minor pests such as leaf folder, armyworms, cut worms etc. have gained importance. In a study conducted by the International Rice Research Institute (IRRI), it was found that, on average, farmers lose 37% of their rice yield to pests and diseases, and that these losses can range between 24% and 41% depending on the production situation (http://irri.org). All the pests are generally kept under check by their natural enemies (parasitoids and predators) by feeding on them. The food web of their relationships prevents the explosion of their populations and keeps them under economic thresholds mimimising the pesticide use.
Why are pollinators declining? New research suggests neonicotinoids are to blame.
When we talk of the crop production we hardly remember to acknowledge the services of these tiny pollinators and also don’t bother to safeguard them when we invest a lot in plant protection. These pollinators play an elemental role in an important process of nature known as pollination. Pollination is an important process in both human managed and natural terrestrial ecosystems. According to the Food and Agriculture Organisation of the United Nations pollination is one of the essential ecosystem services. Continue reading →
Here’s a taste of some of the latest stories about plant health, including a new banana disease identified in Africa, ways to deal with oil seed rape pests after the neonicotinoid restrictions and the role of agricultural cooperatives and storage in rural Ethiopia.
A new protein discovered in the venom of Australian tarantulas can also kill insect pests that consume the venom orally. The protein known as orally active insecticidal peptide-1 (OAIP-1) was found to be highly toxic to insects that consumed it, with a similar efficacy to the neonicotinoid insecticide imidacloprid. In particular, the protein was found to be highly toxic to the cotton bollworm, Helicoverpa zea.
Many spider species have evolved insecticidal toxins in their venom, which they inject into the prey through their fangs. Consequently it has often been presumed that the venom would not be toxic when ingested orally by insects pests, and therefore would not be suitable for use as an insecticide. Conversely, the scientists in this study discovered it is possible to isolate spider venom peptides with high levels of oral insecticidal activity. The team used the venom from Selenotypus plumipes which is a large tarantula native to Australia which despite its large size is not harmful to humans.
Here’s a taste of some of the latest stories about plant health, including cassava’s huge potential as a 21st century crop in Africa, the discovery of nematode resistant wheat and Brazil to launch biofungicide against witch’s broom.
Click on the link to read more of the latest plant health news!
After a European Commission vote yesterday (Monday 29th April 2013), Europe will enforce the world’s first continent-wide ban on neonicotinoid insecticides after concerns about their non-target impact on bee pollinators.
The vote by the 27 European Union member states on whether to suspend the use of neonicotinoid insecticides was supported by 15 nations. The UK did not support the ban.