Plant Influence in Symbiotic Nitrogen Fixation

摘要: One of the preoccupations people involved in problems agriculture is to enable farmers use cheapest, most plentiful and efficient sources nitrogen profitable way for crop production. If one assumes a sugar cane production 80t/ha fresh weight with 2% N-content, plants must absorb 1600 Kg/ha N every year. Although long-season C4 species, more photosynthesis than crops, maximum only possible adequate absorption. A non-limiting supply reasonable energy costs, if thinks terms amount coal consumed by modern NH3 industrial plant. However, social environmental caused pollution will be increasingly difficult. And what about nature our present which evolved under domestication marginal supplies mineral nitrogen? This question concern agronomists plant breeders. Adaptive features limited N-supply are: first, N-nutrition controls rate root/shoot growth; second, reduced remobilized from older leaves reproductive system; third, balance growth/vegetative growth shifted reproduction.