Weather-Centric Rangeland Revegetation Planning

Invasive annual weeds negatively impact ecosystem services and pose a major conservation threat on semiarid rangelands throughout the western United States. Rehabilitation of these rangelands is challenging due to interannual climate and subseasonal weather variability that impacts seed germination, seedling survival and establishment, annual weed dynamics, wildfire frequency, and soil stability. Rehabilitation and restoration outcomes could be improved by adopting a weather-centric approach that uses the full spectrum of available site-specific weather information from historical observations, seasonal climate forecasts, and climate-change projections. Climate data can be used retrospectively to interpret success or failure of past seedings by describing seasonal and longer-term patterns of environmental variability subsequent to planting. A more detailed evaluation of weather impacts on site conditions may yield more flexible adaptive-management strategies for rangeland restoration and rehabilitation, as well as provide estimates of transition probabilities between desirable and undesirable vegetation states. Skillful seasonal climate forecasts could greatly improve the cost efficiency of management treatments by limiting revegetation activities to time periods where forecasts suggest higher probabilities of successful seedling establishment. Climate-change projections are key to the application of current environmental models for development of mitigation and adaptation strategies and for management practices that require a multidecadal planning horizon. Adoption of new weather technology will require collaboration between land managers and revegetation specialists and modifications to the way we currently plan and conduct rangeland rehabilitation and restoration in the Intermountain West.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

Human prefrontal cortex gene regulatory dynamics from gestation to adulthood at single-cell resolution

Published: October 31, 2022Human brain development is underpinned by cellular and molecular reconfigurations continuing into the third decade of life. To reveal cell dynamics orchestrating neural maturation, we profiled human prefrontal cortex gene expression and chromatin accessibility at single-cell resolution from gestation to adulthood. Integrative analyses define the dynamic trajectories of each cell type, revealing major gene expression reconfiguration at the prenatal-to-postnatal transition in all cell types followed by continuous reconfiguration into adulthood and identifying regulatory networks guiding cellular developmental programs, states, and functions. We uncover links between expression dynamics and developmental milestones, characterize the diverse timing of when cells acquire adult-like states, and identify molecular convergence from distinct developmental origins. We further reveal cellular dynamics and their regulators implicated in neurological disorders. Finally, using this reference, we benchmark cell identities and maturation states in organoid models. Together, this captures the dynamic regulatory landscape of human cortical development.Charles A. Herring, Rebecca K. Simmons, Saskia Freytag, Daniel Poppe, Joel J.D. Moffet, Jahnvi Pflueger, Sam Buckberry, Dulce B. Vargas-Landin, Olivier Cle, ment, Enrique Gon, i Echeverrı, a, Gavin J. Sutton, Alba Alvarez-Franco, Rui Hou, Christian Pflueger, Kerrie McDonald, Jose M. Polo, Alistair R.R. Forrest, Anna K. Nowak, Irina Voineagu, Luciano Martelotto, and Ryan Liste

Densidade populacional de Ralstonia solanacearum em cultivares de batata a campo Population densities of Ralstonia solanacearum on potato cultivars in the field

A ocorrência de populações latentes de Ralstonia solanacearum em plantas de batata (Solanum tuberosum) pode representar fonte de inóculo de potencial desconhecido. Além disso, também é desconhecido se a população latente da bactéria é menor em cultivares resistentes do que em cultivares suscetíveis. Com a finalidade de estudar estes aspectos, um experimento foi conduzido a campo em dois locais no Estado do Rio Grande do Sul, Brasil. O objetivo foi verificar se havia relação entre a densidade populacional e o grau de resistência de cultivares de batata. O experimento foi conduzido em Eldorado do Sul, durante o período de primavera, e em Caxias do Sul, durante o período de outono. Tubérculos das cultivares Achat, Baronesa, Elvira, Macaca, Monte Bonito e Trapeira foram inoculados com uma estirpe de R. solanacearum, biovar II, e plantados a campo. A densidade populacional da bactéria foi estimada em plantas com e sem sintomas de murcha, através de ELISA e imunofluorescência. Não houve evidência da relação entre densidade populacional da bactéria e cultivar. Além disso, a densidade populacional na cultivar Achat, caracterizada como a mais resistente entre as cultivares testadas, foi igual à registrada nas outras cultivares.<br>The occurrence of latent populations of Ralstonia solanacearum on potato (Solanum tuberosum) plants may represent inoculum source of unknown potential. Besides, it is also unknown if the latent population of the bacterium is lower in resistant than in susceptible cultivars. In order to study these points, an experiment was conducted in the field in two locations in Rio Grande do Sul State, Brazil. The objective was to verify the relationship between R. solanacearum population density and the potato cultivar resistance. The experiment was conducted in Eldorado do Sul, during the Spring, and in Caxias do Sul, during the Fall. Tubers of Achat, Baronesa, Elvira, Macaca, Monte Bonito, and Trapeira cultivars were inoculated with a R. solanacearum strain, biovar II, and planted in the field. Population density of the bacterium was estimated in the assymptomatic and wilted plants, by ELISA and imunofluorescence techniques. No evidence of relationship between population density of R. solanacearum and cultivar was found. Besides, the population density on Achat, known as the most resistant, one was similar to the other cultivars