SHE

STAND UP AGAINST BEAN WEEVILS WITH GARLIC AND SPRING ONIONS

 

Bean weevils have become a veritable albertross in kitchens, pantries and stores. After careful seletion wading through markets for insect free grains of cowpea, you store the grains away in paint buckets, sacs, or polythene bags with a feeling of satisfaction and food (bean) security you soon find out that your beans have become home for unwanted small brown insects commonly called weevils. 

Adult bean weevil

Eggs and damage holes of bean weevil 

Females lay the eggs cemented to the bean or the pod. In 2 - 3 days the eggs hatch into gurblike larvae which bores into the seed where it makes a 'window' before becoming pupa, a resting stage before adulthood. The larval and pupal stages are spent inside the bean. The adult emerges through the 'window' leaving a neat round hole. This weevil attacks dried beans; thus this weevil is a serious storage pest. The larval stage of the weevil bore hole  within the beans and eat up almost all the entire bean contents. After the pupa stage in the beams t adults emerge through a round hole in the seed coat. The damage done is a combination of the feeding and contamination with frass. This calls for control measures that are cheap, readily available and environmentally friendly. In a bid to find such quality means of keeping these weevils away from stored beans  we carried out laboratory bioassays to investigate the bioactivity of powders, extracts, and essential oils from garlic (Allium sativum L.) (Alliaceae) and Spring onion (A. fistulosum L) .(Liliaceae)against adults, eggs,and larvaeof bean weevils technically called Callosobruchus maculatus F.
On thebasis of48hr median lethal toxicity (LC50), test plant powders and extracts from garlic were more toxic to the weevils than those from spring onion. The 48hr LC50 values for the powder against the test insect species were 9.66g/kg and 26.29g/kg for garlic and spring onion  fistulosum, respectively. Also the 48hr LC50 values obtained show that water extracts of the garlic 0.11g/L and 0.411g/L  for spring onion were more toxic to the weevils than the corresponding ethanol
extracts. The study shows that garlic spring onion have potentials for protecting stored beans from
damage by storage weevils named C. maculatus.
Details of this study can be found here http://www.google.com.ng/url?sa=t&rct=j&q=abiodun+denloye&source=web&cd=13&v ed=0CDYQFjACOAo&url=http%3A%2F%2Fdownloads.hindawi.com%2Fjournals%2Fpsyche%2F2010%2F958348.pdf&ei=68W8UKGJCdSY0QW35IHgAw&usg=AFQjCNGb3xsflKT1SUISW6W5o-ctbAZljw