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To achieve the ambitious goals of the UN Decade on Ecosystem Restoration, restoration frameworks should embrace the diversity of ecosystems found on Earth, including open-canopy ecosystems, which have been largely overlooked. Considering the paucity of scientific foundations promoting restoration science, policy, and practice for open tropical ecosystems, we provide overarching guidelines to restore the campo rupestre, a Neotropical, open megadiverse grassland that has been increasingly threatened by multiple human activities, especially mining. Restoration techniques for tropical grasslands are still at its infancy, and attempts to restore campo rupestre have had, so far, low to moderate success, highlighting the need for a tailored restoration framework. In a scenario of increasing degradation and scarcity of on-site restoration experiments, we propose 10 principles to improve our ability to plan, implement, and monitor restoration in campo rupestre: (1) include socioeconomic dimensions, (2) implement active restoration, (3) keep low soil fertility, (4) restore disturbance regimes, (5) address genetic structure and adaptation potential, (6) restore geographically restricted and specialized ecological interactions, (7) incorporate functional approaches, (8) use seed-based restoration strategies to enhance biodiversity, (9) translocation is inevitable, and (10) long-term monitoring is mandatory. Our principles represent the best available evidence to support better science and practice for the restoration of campo rupestre and, to some extent, can be useful for other megadiverse, fire-prone, and nutrient-poor ecosystems.

Novel sources of resistance are continuously needed to combat anthracnose disease in common bean (Phaseolus vulgaris L.) caused by the hypervariable pathogen Colletotrichum lindemuthianum (Sacc. and Magnus) Briosi and Cavara. We sought to characterize the novel anthracnose resistance in Andean common bean landrace ‘Jalo Listras Pretas’ (JLP). Jalo Listras Pretas is resistant to races 9, 64, 65, and 73 of the anthracnose pathogen used in this study. To examine inheritance of anthracnose resistance in JLP, F 2 populations JLP/Mexico 222 and JLP/Cornell 49242 were inoculated with discriminating races of the pathogen. Segregation for resistance in both F 2 populations fi t a 3:1 resistant/susceptible ratio suggesting that the anthracnose resistance in JLP is controlled by a single dominant gene. To establish independence of the resistance gene in JLP from other published resistance genes, allelism tests were conducted with 14 F 2 populations derived from crossing JLP with Andean cultivars carrying anthracnose resistance genes Co-1, Co-1 2 , Co-1 3 , Co-1 5 , and Co-12, and with Middle American cultivars with Co-2, Co-3, Co-4 3 , Co-5, Co-6, Co-7, Co-9, Co-10, and Co-11. Results revealed the resistance gene in JLP was independent of the Andean loci Co-1 and Co-12, and the nine Middle American anthracnose resistance genes. The symbol Co-13 was assigned to this newly discovered anthracnose resistance gene in Brazilian Andean common bean landrace JLP.

Comparisons of species richness among assemblages using different sample sizes may produce erroneous conclusions due to the strong positive relationship between richness and sample size. A current way of handling the problem is to standardize sample sizes to the size of the smallest sample in the study. A major criticism about this approach is the loss of information contained in the larger samples. A potential way of solving the problem is to apply extrapolation techniques to smaller samples, and produce an estimated species richness expected to occur if sample size were increased to the same size of the largest sample. We evaluated the reliability of 11 potential extrapolation methods over a range of different data sets and magnitudes of extrapolation. The basic approach adopted in the evaluation process was a comparison between the observed richness in a sample and the estimated richness produced by estimators using a sub-sample of the same sample. The Log-Series estimator was the most robust for the range of data sets and sub-sample sizes used, followed closely by Negative Binomial, SO-J1, Logarithmic, Stout and Vandermeer, and Weibull estimators. When applied to a set of independently replicated samples from a species-rich assemblage, 95% confidence intervals of estimates produced by the six best evaluated methods were comparable to those of observed richness in the samples. Performance of estimators tended to be better for species-rich data sets rather than for those which contained few species. Good estimates were found when extrapolating up to 1.8-2.0 times the size of the sample. We suggest that the use of the best evaluated methods within the range of indicated conditions provides a safe solution to the problem of losing information when standardizing different sample sizes to the size of the smallest sample.

Strains of Colletotrichum isolated from berries of Coffea arabica from Angola and Malawi were identified as C. coffeanum causing coffee berry disease (CBD). The isolates were highly aggressive to berries of the cultivar ‘Catimor’ and produced high numbers of acervuli and extremely large masses of pink conidia when cultivated in the dark. These strains are apparently different in aggressiveness and morphology to those described in the past from Kenya.