Anthracnose fruit rot affecting field peppers ( L.) has been reported in Ontario, Canada, leading to significant crop losses of up to 80% over the past three years. Ten symptomatic fruits per field, exhibiting one or more soft, sunken lesions covered with salmon-colored spore masses (Fig.
View Article and Find Full Text PDFThe pepper weevil, Anthonomus eugenii Cano, is an economically important pest of field and greenhouse pepper crops in North America. In this study, a series of insecticides covering a broad-spectrum of insecticidal modes of action were assessed for their potential in managing the pepper weevil under laboratory and greenhouse conditions. To accomplish this, laboratory mini-spray tower and greenhouse cage trials were conducted that evaluated the efficacy of 16 conventional, reduced-risk, and microbial insecticides.
View Article and Find Full Text PDFAlternative metrics exist for representing variation in plant body size, but the vast majority of previous research for herbaceous plants has focused on dry mass. Dry mass provides a reasonably accurate and easily measured estimate for comparing relative capacity to convert solar energy into stored carbon. However, from a "plant's eye view", its experience of its local biotic environment of immediate neighbors (especially when crowded) may be more accurately represented by measures of "space occupancy" (S-O) recorded rather than dry mass measured after storage in a drying oven.
View Article and Find Full Text PDFThe selection consequences of competition in plants have been traditionally interpreted based on a "size-advantage" hypothesis - that is, under intense crowding/competition from neighbors, natural selection generally favors capacity for a relatively large plant body size. However, this conflicts with abundant data, showing that resident species body size distributions are usually strongly right-skewed at virtually all scales within vegetation. Using surveys within sample plots and a neighbor-removal experiment, we tested: (1) whether resident species that have a larger maximum potential body size (MAX) generally have more successful local individual recruitment, and thus greater local abundance/density (as predicted by the traditional size-advantage hypothesis); and (2) whether there is a general between-species trade-off relationship between MAX and capacity to produce offspring when body size is severely suppressed by crowding/competition - that is, whether resident species with a larger MAX generally also need to reach a larger minimum reproductive threshold size (MIN) before they can reproduce at all.
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