A synthesis of evidence for the effects of interventions to conserve peatland vegetation: Overview and critical discussion

Peatlandsare valuable but threatenedecosystems. Intervention to tackle direct threats is often necessary, but should be informed by scientific evidence to ensure it is effective and efficient. Herewe discuss a recent synthesis of evidence for the effects of interventions to conserve peatland vegetation -a fundamental component of healthy, functioning peatland ecosystems. The synthesis is unique in its broad scope (global evidence for a comprehensive list of 125 interventions) and practitioner-focused outputs (short narrative summaries in plain English, integrated into a searchable online database). Systematicliteraturesearches, supplemented by recommendationsfrom an international advisory board, identified162 publications containing 296 distinct tests of 66 of the interventions. Most of the articles studiedopen bogs or fens in Europe or North America. Only 36 interventions weresupported by sufficient evidence to assess their overall effectiveness. Mostof these interventions(85%) hadpositiveeffects, overall,on peatland vegetation-although this figure is likelyto have beeninflated by publication bias. We discuss how to use the synthesis, critically,to informconservation decisions.Reflecting on the content of the synthesiswe make suggestions for the future of peatland conservation,from monitoring overappropriate timeframes to routinely publishing resultsto build up the evidence base.MAVA, Arcadi

Tomato: a crop species amenable to improvement by cellular and molecular methods

Tomato is a crop plant with a relatively small DNA content per haploid genome and a well developed genetics. Plant regeneration from explants and protoplasts is feasable which led to the development of efficient transformation procedures. In view of the current data, the isolation of useful mutants at the cellular level probably will be of limited value in the genetic improvement of tomato. Protoplast fusion may lead to novel combinations of organelle and nuclear DNA (cybrids), whereas this technique also provides a means of introducing genetic information from alien species into tomato. Important developments have come from molecular approaches. Following the construction of an RFLP map, these RFLP markers can be used in tomato to tag quantitative traits bred in from related species. Both RFLP's and transposons are in the process of being used to clone desired genes for which no gene products are known. Cloned genes can be introduced and potentially improve specific properties of tomato especially those controlled by single genes. Recent results suggest that, in principle, phenotypic mutants can be created for cloned and characterized genes and will prove their value in further improving the cultivated tomato.