Nodular diagnosis for ecological engineering of the symbiotic nitrogen fixation with legumes

摘要: As a major contributor to the reduced nitrogen pool in biosphere, symbiotic fixation by legumes plays critical role sustainable production system. However this legume contribution varies with physico-chemical and biological conditions of nodulated-root rhizosphere. In order assess abiotic biotic constrains that might limit symbiosis at agroecosystem level, nodular diagnosis is proposed common bean as model grain-legume, source plant proteins for world human nutrition. The engineering addressed participatory assessment recombinant inbred lines contrasting their efficiency use phosphorous fixation. With methodology, field-sites chosen farmers an area cereal-cropping Mediterranean basin, large spatial temporal variation nodulation was found. Soil P availability limiting factor rhizobial symbiosis. relate field measurements progress functional genomics symbiosis, situ RT-PCR on nodule sections has been implemented showing phytase gene expressed cortex significantly higher number transcripts P-efficient RILs. It concluded various tools indicators are available developing ecological particular its beneficial bio-geochemical cycle N, also C.