Emerging and established technologies to increase nitrogen use efficiency of cereals

HERRERA JM; G RUBIO; L LEVY HÄNER; J A. DELGADO ; CA LUCHO CONSTANTINO; S ISLAS-VALDEZ; D PELLET

Agronomy

MDPI

Lugar: Basel; Año: 2016 vol. 6 p. 1 - 25

Abstract:Nitrogen(N) fertilizers are one of the most expensive inputs in agricultural settings.Additionally,the loss of N increases costs, contributes to soil acidification, and causesoff-sitepollutionof the air, groundwater and waterways. This study reviews current knowledgeabouttechnologiesfor N fertilization with potential to increase N use efficiency and reduce itsnegativeeffectson the environment. Classic inorganic sources such as urea and ammonium sulfateare themajorsources utilized, while controlled N release fertilizers have not been significantlyadopted forcerealsand oil crops. Microorganisms, with the exception of Rhizobium sp. in soybeans,are alsonotwidely used nowadays (e.g., plant growth-promoting bacteria and cynobacteria).The interestin implementingnew N fertilization knowledge is stimulating the development of sensors todiagnosethe N status and decision support systems for integrating several variables tooptimizesources,rates and methods of application. Among potential new technologies we identifiedtheincipientdevelopment of nanofertilizers, nutrient formulations to coat seeds, andrecycled nutrients.Furthermore,increasing concern about the environmental consequences of N may facilitate theimplementationof innovations outside the farm such as more effective regulations to guide Nfertilizationand methods to manufacture N fertilizers that are more energy-efficient and lessCOequivalent emitting.