Epidemiological aspects of Phyllosticta citricarpa colonization and viability in Citrus sinensis

Journal of Plant Diseases and Protection - Citrus black spot (CBS) is a disease caused by the fungus Phyllosticta citricarpa that is associated with significant yield losses. The pathogen forms...     

Xanthine degradation and related enzyme activities in leaves and fruits of two coffea species differing in caffeine catabolism.

The degradation of xanthine was studied in young and aged leaves and in immature and mature fruits of Coffea arabica and Coffea dewevrei, which differ with respect to caffeine catabolism. Radioisotope feeding experiments showed that leaves degraded xanthine more readily than fruits but that mature fruits and aged leaves were less efficient than younger tissues. In all cases, a significant part of the recovered radioactivity was in the ureides. Xanthine dehydrogenase was characterized as the enzyme responsible for xanthine degradation, and its activity and that of uricase were consistent with the results obtained in the radioisotope feeding experiments. Activities of allantoinase and allantoate amidohydrolase could not be detected. Considerable levels of endogenous allantoin and allantoic acid were found in fruits and leaves. Therefore, ureide accumulation might be a consequence of low enzyme activity. There was no positive correlation between urease activity and the data from the radioisotope feeding experiments.     

Grundsätzliche Möglichkeiten in der Behandlung des Sturmholzes bei Anwendung moderner Insektizide

Ohne ZusammenfassungDie Untersuchungen wurden in dankenswerter Weise durch das Land Nordrhein-Westfalen und die Deutsche Forschungsgemeinschaft unterstützt.     

Responses of soil and plants to spatio-temporal changes in landscape under different land use in Imo watershed,southern Nigeria

Soil and plant compositions have been affected by human activities in Imo watershed, southern Nigeria. The study examined the responses of soil and plants to changes in landscape under different land use. It was hypothesized that though forest had higher soil organic carbon (OC) and organic matter (OM), it was the most altered land use with substantial loss of biodiversity. Data were collected covering soil properties and plant compositions. Arable land (AL), forestland (FL), grassland (GL), shrubland hills (SL), urban built-up green (UL), Freshwater swamp-mangrove wetland (WL) and water bodies (WB) were classified as the main land use by using ArcGIS 10.1 and Food and Agricultural Organization (FAO) land-use classification system. One-way analysis of variance followed by post-hoc test was used to determine the mean differences in years and land use for various soil properties and plant parameters. Results revealed that soil nutrient concentrations decreased by at least 50% across land use. Leucaena leucocephala, Vernonia amygdalina, Panicum maximum, Lablab purpreus, Vernonia nigritiana and Elaeis guineensis were dominant with high cover. Species diversity showed significantly negative correlations with species evenness and R-factor (p < 0.05), but positive correlations with total nitrogen and OM and OC (p < 0.001). To restore and increase soil and plant biodiversity, human activities need to be regulated by introducing sustainable agriculture and logging.     

Structure and genetic diversity of macauba [Acrocomia aculeata (Jacq.) Lodd. ex Mart.] approached by SNP markers to assist breeding strategies

Genetic Resources and Crop Evolution - Macauba palm [Acrocomia aculeata (Jacq.) Lodd. ex Mart.] is a perennial oil, it stands out for having several characteristics of commercial interest, mainly...