15 research outputs found

    Pinus patula

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    In response to the Fusarium circinatum pine pathogen threat in southern Africa, research has been conducted on the development of F. circinatum-tolerant P. patula and P. patula hybrids. The objective of this study was to investigate the propagation potential of these taxa in two vegetative propagation systems, hydroponic sand beds and polythene bags with composted pine bark growing medium. Significant differences (p< 0.001) in mortality associated with F. circinatum were observed between the P. patula x P. tecunumanii (LE) hybrid (6%) and P. patula (19–23%). No significant differences in mortality associated with F. circinatum were observed within P. patula x P. tecunumanii (LE) families, which ranged from zero to 15%. Significant mortality differences (p < 0.001) were observed between P. patula families, which ranged from 8% to 44%. The number of rooted cuttings produced, per hedge established, over the four-year period was significantly better (p 0.001) in the P. patula x P. tecunumanii (LE) hybrid (52) than in P. patula (29–33). Significant differences (p < 0.001) were also observed in the number of rooted cuttings produced per family, with P. patula x P. tecunumanii (LE) families ranging from 35 to 70 cuttings per hedge plant established and P. patula families between 20 and 42 cuttings. Over the four-year duration of the trial all taxa showed increased productivity in hedges grown in a hydroponic sand bed system, which received more consistent fertilisation and yielded an average of 55 rooted cuttings per hedge, over those grown in polythene bags with composted pine bark medium, which yielded 41 cuttings on average. This study demonstrated that the P. patula x P. tecunumanii (LE) hybrid is a feasible substitute for P. patula in both vegetative propagation systems, as it not only shows improved survival, through increased F. circinatum tolerance, but also improved productivity.http://www.tandfonline.com/loi/tsfs20hb201

    What Triggers The Resolution of Alcohol Problems Without Treatment?

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    This study investigated natural recoveries (self-change) from alcohol problems, and overcame several methodological problems that affected the few previous studies of this phenomenon. Three groups of individuals who had resolved an alcohol problem without treatment were interviewed about their drinking history, life events that occurred during the year prior to their resolution, and factors that helped maintain their resolution. As a control for prevalence of life events, a control group of nonresolved, nontreated alcohol abusers were interviewed about events in a randomly selected year. Collaterals were interviewed for all subjects. No life event or constellation of events was differentially associated with the resolutions across the three resolved groups or differentiated the resolved and nonresolved groups. Interviews with resolved subjects were qualitatively analyzed-the majority (57%) of recoveries were characterized as involving a cognitive evaluation or appraisal of the pros and cons of drinking. Spousal support was reported by the greatest number of resolved subjects as having helped them maintain their resolution. Findings from this study may provide direction for developing new treatment strategies and for accelerating self-change among problem drinkers in the community. The study also demonstrates the importance of using a control group, without which very different conclusions might have been drawn
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