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The remnant floral diversity of a naturally reclaimed area proximal to an abandoned mine was assessed. The coal mine site, the Incident zone (IZ) and an unsullied site, the Control zone (CZ), were sampled. Using a 5 m2 quadrat, the floristic composition was determined by the occurrence, distribution analysis, and species diversity indices. The study revealed a degraded vegetation type and recorded a total of 60 species, 53 genera and 27 families. Both the IZ and CZ shared 26.67% species similarity, while 36.67% are were unique to each zone. Five species were dominant (Ageratum conyzoides, Panicum maximum, Calopogonium mucunoides, Chromolaena odorata). While the dominant genera vary between IZ (Borreria, Dioscorea, Ipomoea, and Phyllanthus) and CZ (Desmodium, Euphorbia, and Ipomoea), Asteraceae and Poaceae were the dominant families in both zones. Forbs were the most dominant life forms in both zones; Cyclosorus sp. and Adiantum sp. were only found on the IZ, whereas, Kyllinga erecta and Mariscus alternifolius were exclusive to the CZ. Our results reflect that species composition and vegetation paradigm in the study area could be influenced by coal mining, farming, infrastructural installations and climate. Hence, we suggest future studies to investigate how the species adapt to the environment. Although most of the species encountered belonged to lower-risk conservation, the conservation of the species to this area is imperative.

This study was carried out to determine the effects of single infections and co-infections of three unrelated viruses on three cowpea cultivars (one commercial cowpea cultivar "White" and 2 IITA lines; IT81D-985 and TVu 76). The plants were inoculated with Cowpea aphid-borne mosaic virus (CABMV), genus Potyvirus, Cowpea mottle virus (CMeV), genus Carmovirus and Southern bean mosaic virus (SBMV), genus Sobemovirus singly and in mixture (double and triple) at 10, 20, and 30 days after planting (DAP). The treated plants were assessed for susceptibility to the viruses, growth, and yield. In all cases of infection, early inoculation resulted in higher disease severity compared with late infection. The virus treated cowpea plants were relatively shorter than buffer inoculated control plants except the IT81D-985 plants that were taller and produced more foliage. Single infections by CABMV, CMeV, and SBMV led to a complete loss of seeds in the three cowpea cultivars at 10 DAP; only cultivar White produced some seeds at 30 DAP. Double and triple virus infections led to a total loss of seeds in all three cowpea cultivars. None of the virus infected IITA lines produced any seeds except IT81D-985 plants co-infected with CABMV and SBMV at 30 DAP with a reduction of 80%. Overall, the commercial cultivar "White" was the least susceptible to the virus treatments and produced the most yield (flowers, pods, and seeds). CABMV was the most aggressive of these viruses and early single inoculations with this virus resulted in the premature death of some of the seedlings. The presence of the Potyvirus, CABMV in the double virus infections did not appear to increase disease severity or yield loss. There was no strong evidence for synergistic interactions between the viruses in the double virus mixtures.

Several lines of evidence suggest that the circadian clock is constructed of multiple molecular feedback oscillators that function to generate robust rhythms in organisms. However, while core oscillator mechanisms driving specific behaviors are well described in several model systems, the nature of other potential circadian oscillators is not understood. Using genetic approaches in the fungus Neurospora crassa, we uncovered an oscillator mechanism that drives rhythmic spore development in the absence of the well-characterized FRQ/WCC oscillator (FWO) and in constant light, conditions under which the FWO is not functional. While this novel oscillator does not require the FWO for activity, it does require the blue-light photoreceptor CRYPTOCHROME (CRY); thus, we call it the CRY-dependent oscillator (CDO). The CDO was uncovered in a strain carrying a mutation in cog-1 (cry-dependent oscillator gate-1), has a period of ∼1 day in constant light, and is temperature-compensated. In addition, cog-1 cells lacking the circadian blue-light photoreceptor WC-1 respond to blue light, suggesting that alternate light inputs function in cog-1 mutant cells. We show that the blue-light photoreceptors VIVID and CRY compensate for each other and for WC-1 in CRY-dependent oscillator light responses, but that WC-1 is necessary for circadian light entrainment.