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The Pecan (Carya illinoensis) is the most important species that belongs to the Carya genus. It is cultivated mainly for its nut, which is rich in oils and proteins, and for its good quality wood. Pecan is conventionally propagated by budding or grafting onto rootstocks obtained by open pollination. However, these techniques are not very efficient due to low propagation rates, poor survival and difficult establishment. Therefore, in vitro propagation of pecan can play a very important role in rapid multiplication of cultivars with desirable traits and production of healthy and disease-free plants in a short time. In the present review, the improvements over the years in the propagation of pecans, the refinements of protocols for obtaining high shoot multiplication and regeneration through organogenesis and/or somatic embryogenesis is discussed. Some basics of genetic transformation and its possible benefits are also discussed.

The use of natural products developed from wild plants is gaining interest and momentum throughout the world in both developed and developing countries. In developing countries the use of natural plant extracts is simply the result of the inability of subsistence farmers to afford commercial synthetic pesticides. However, in developed countries this is largely due to consumer resistance towards synthetic chemicals, including antimicrobial, herbicidal and bio-stimulatory agents, believed to be potentially hazardous to the environment and human health. In this chapter an overview of the latter three pesticide groups is supplied in terms of its current 'natural product' status from an integrated pest management perspective as it is applied in the agricultural industry. First, some background is provided in order to cover the history of natural product development in these three pesticide categories. Second, a short synopsis of screening programmes that identified wild plants containing natural compounds which have the potential to be considered in natural product developing programmes is supplied. Lastly, the outcome of these development programmes that realized commercialized natural products is covered.

SummaryWe previously reported on the in vitro antifungal activity of a crude whole plant extract from Eucomis autumnalis against seven economically important plant pathogenic fungi. A crude extract of the bulb showed similar in vitro mycelial growth inhibition of the same plant pathogenic fungi as well as that of an eighth fungus, Mycosphaerella pinodes, the cause of black spot or Ascochyta blight, in peas. Subsequently, fourth internode leaves were removed from 4 wk old pea plants, placed on moist filter paper in Petri dishes and inoculated with an M. pinodes spore suspension before and after treatment with the extract. The control of Ascochyta blight by different concentrations of the crude E. autumnalis extract was followed in vivo by leaf symptoms over a 6 day period at 20°C in a growth cabinet. The crude extract prevented M. pinodes spore infection of the leaves when the leaves were inoculated with spores both before or after treatment with the extract, confirming complete inhibition of spore germination. The crude E. autumnalis extract showed no phytotoxic reaction on the leaves even at the highest concentration applied.

Background: Microbial infections are one of the major causes of death globally. This is attributed to the rising costs of primary healthcare and its inaccessibility especially in developing countries. Moreover, there has been an increase in microbial strains that have reduced susceptibility to antimicrobial drugs. Research on the antimicrobial properties of medicinal plants, which could address these problems, has become more important as they present fewer side effects when compared to the antibiotics currently in use. This study evaluated the antimicrobial properties of a methanolic extract from Buxus macowanii in order to assess its potential in the development of novel antimicrobial drugs. Methods: Antimicrobial activity of the extract was evaluated using the broth microdilution method. The effects of B. macowanii on the morphology of B. cereus were observed using Scanning and Transmission electron microscopy. Chemical profiling of the plant extract was performed using the GCMS. Results: The extract showed antimicrobial activity against all the microbial species used. Microscopic examination of the cells of B. cereus cells treated with Buxus macowanii showed some changes in morphology such as damage of the cell wall, swelling of the cells and incomplete cell division that eventually resulted in cell death. Neophytadiene, an antimicrobial compound was detected in the extract using GCMS. Conclusion: The morphological disruptions of the cell wall of Bacillus cereus explain the antimicrobial properties of B. macowanii and indicate its possible application in the development of natural antimicrobial drugs.