CullingIn biology, culling is the process of segregating organisms from a group according to desired or undesired characteristics. In animal breeding, it is the process of removing or segregating animals from a breeding stock based on a specific trait. This is done to exaggerate desirable characteristics, or to remove undesirable characteristics by altering the genetic diversity of the population. For livestock and wildlife, culling often refers to the act of killing removed animals based on their individual characteristics, such as their sex or species membership, or as a means of preventing infectious disease transmission.
Agriculture in MesoamericaAgriculture in Mesoamerica dates to the Archaic period of Mesoamerican chronology (8000–2000 BC). At the beginning of the Archaic period, the Early Hunters of the late Pleistocene era (50,000–10,000 BC) led nomadic lifestyles, relying on hunting and gathering for sustenance. However, the nomadic lifestyle that dominated the late Pleistocene and the early Archaic slowly transitioned into a more sedentary lifestyle as the hunter gatherer micro-bands in the region began to cultivate wild plants.
Convertible husbandryConvertible husbandry, also known as alternate husbandry or up-and-down husbandry, is a method of farming whereby strips of arable farmland were temporarily converted into grass pasture, known as leys. These remained under grass for up to 10 years before being ploughed under again, while some eventually became permanent pasturage. It was a process used during the 16th century through the 19th century by "which a higher proportion of land was used to support increasing numbers of livestock in many parts of England.
Rouille noirePuccinia graminis est une espèce de champignons basidiomycètes de la famille des Pucciniaceae. Cette espèce parasite les plantes céréalières (avoine, blé, orge, triticale) chez lesquelles elle provoque la maladie de la « rouille noire ». En 1944, un agronome américain, Norman Borlaug, spécialiste des pathologies végétales se rendit au Mexique pour lutter contre une épidémie de rouille noire à l'origine d'une famine généralisée. En croisant différentes variétés de blé du monde entier, il obtint un hybride résistant à la rouille et à haut rendement.
Push-pull (agriculture)vignette|droite|Le Desmodium dégage des substances chimiques qui éloignent les insectes ravageurs. Le push-pull (le pousser-piéger), aussi appelé répulsion-attraction, est une approche de lutte biologique qui consiste à « chasser » les insectes ravageurs d'une culture principale et à les « charmer » vers la lisière du champ. Cette méthode dépend de l'agencement pensé de plantes dotées de la capacité biologique ou chimique de repousser, attirer ou piéger les insectes, évitant l'utilisation d'insecticides de synthèse ou d'OGM.
Nutrient managementNutrient management is the science and practice directed to link soil, crop, weather, and hydrologic factors with cultural, irrigation, and soil and water conservation practices to achieve optimal nutrient use efficiency, crop yields, crop quality, and economic returns, while reducing off-site transport of nutrients (fertilizer) that may impact the environment. It involves matching a specific field soil, climate, and crop management conditions to rate, source, timing, and place (commonly known as the 4R nutrient stewardship) of nutrient application.
