Essay on The effect of food source (mung bean Vigna radiata vs. black-eyed pea Vigna unguiculata) on relative inhibition of acetylcholinerase due to malaoxon in bean beetle Callosobruchus maculatus
The effect of food source (mung bean Vigna radiata vs. black-eyed pea Vigna unguiculata) on relative inhibition of acetylcholinerase due to malaoxon in bean beetle Callosobruchus maculatus
Background and Hypotheses:
Recent studies, most notably Gbaye et al. (2011, 2012), have investigated the sensitivity of bean beetles in the genus Callosobruchus to organophosphate insecticides (OPs). Economically this is important work given that these beetles are pests that threaten agricultural yields of legumes. OPs work by inhibiting the enzyme acetylcholinerase (AChE) in the beetles. Without this enzyme, the neurotransmitter acetylcholine can't be broken down and its overflow leads to the eventual death of the beetle. Results obtained by…show more content… What's more, our t-value doesn't reach t-critical for even a 80% confidence interval, meaning there is at least a 20% likelihood that the observed difference in means is due to random variation.
Conclusions and Discussion:
A 20% chance that the difference in means is due to random variation is far too great to support the alternative hypothesis – that there is a difference in sensitivity of AChE in C. maculatus to malaoxon bred on mung beans as opposed to black eyed peas. By default our data supports the null hypothesis – that there is no such difference in sensitivity.
However, we don't feel we have yet proven this negative fact. Importantly, we are not aware of what geographical strain of beetle we used in this experiment. Gbaye et al. (2012) observed a statistical difference in AChE activity between C. maculatus beetles bred on mung beans and cowpeas (i.e. black-eyed peas) amongst all three geographical strains tested – those from Cameroon, Brazil, and Yemen. However, the difference in the Cameroon strain was least apparent. This suggests that our strain of beetle may have been from either Cameroon or another location not tested in Gbaye et al. Our experiment should be replicated using beetles of a known geographic strain for comparison. Also, our sample sizes were presumably much smaller than theirs –
