Tropical cyclone impacts on seagrass-associated fishes in a temperate-subtropical estuary

Major storms can alter coastal ecosystems in several direct and indirect ways including habitat destruction, stormwater-related water quality degradation, and organism mortality. From 2010–2020, ten tropical cyclones impacted coastal North Carolina, providing an opportunity to explore ecosystem responses across multiple storms. Using monthly trawl and contemporaneous seagrass surveys conducted in Back Sound, NC, we evaluated how cyclones may affect the nursery role of shallow-water biogenic habitats by examining seagrass-associated fish responses within a temperate-subtropical estuary. We employed a general before-after-control-impact approach using trawls conducted prior (before) and subsequent (after) to storm arrival and years either without (control) or with (impact) storms. We examined whether effects were apparent over short (within ~three weeks of impact) and seasonal (May-October) timescales, as well as if the magnitude of storm-related shifts varied as a function of storm intensity. Our findings suggest that the ability of these shallow-water habitats to support juvenile fishes was not dramatically altered by hurricanes. The resilience exhibited by fishes was likely underpinned by the relative persistence of the seagrass habitat, which appeared principally undamaged by storms based upon review of available–albeit limited seagrass surveys. Increasing cyclone intensity, however, was correlated with greater declines in catch and may potentially underlie the emigration and return rate of fish after cyclones. Whether estuarine fishes will continue to be resilient to acute storm impacts despite chronic environmental degradation and predicted increases major tropical cyclone frequency and intensity remains a pressing question

Implementação da seleção recorrente no melhoramento de plantas autógamas através da macho-esterilidade Implementation of recurrent selection in plant breding of autogamous crops through male sterility

Os sistemas de melhoramento convencionais baseados no método genealógico, utilizados principalmente em cereais de estação fria, determinam a redução da variabilidade e da capacidade de recombinação, devido a utilização de um número de genitores limitado nos cruzamentos. O incremento da probabilidade de recombinação através da seleção recorrente pelo aumento do número de cruzamentos pode ser a saída para este problema. A utilização da macho-esterilidade representa uma alternativa viável para propiciar o cruzamento natural em espécies de autofecundação, favorecendo a utilização da seleção recorrente como uma importante ferramenta para o melhoramento de plantas autógamas.<br>The mechanism of pedigree system used in smallgrain cereals reduce genetic variability and recombination capacity due to the limited number of parent used in crosses. The increase in recombination through recurrent selection by maximizing number of crosses may be a solution for this problem. The use of male sterility may overcome the difficult of performing artificial crosses, supporting recurrent selection as a viable and important tool for autogamous crops breeding