Negative frequency-dependent selection should result in equal sex ratios in large populations of dioecious flowering plants, but deviations from equality are commonly reported. A variety of ecological and genetic factors can explain biased sex ratios, although the mechanisms involved are not well understood. Most dioecious species are long-lived and/or clonal complicating efforts to identify st...

The insecticidal activities of methanolic extracts two weedy plants leaves Bidens pilosa L. and Rumex dentatus at three different concentrations 3, 5 7% were tested against stored grain pests, Rice weevil Sitophilus oryzae Saw-toothed beetle Oryzaephilus surinamensis L., Bean Acanthoscelides obtectus Say, compared to Neem oil as a commercial product the same for exposure periods

in survey of infected samples to downy mildew of broadbean, chenopodium murale and rumex chalpensis using olympus microscope (bh2) and valid keys and recently published papers, two species were identified (choi et al. 2009, ershad 2009, telle & thines 2012).