chapter  1
14 Pages

The Stress Environment

WithAbraham Blum

The initial stages of plant domestication from native vegetation must have involved genetic adaptation to the prevailing environment. Plant science, however, requires a measure of water use by plants in the definition of the moisture environment. Thus, for example, Thornthwaite and Mather recognized that evapotranspiration was affected by solar radiation, the atmospheric capacity for removing water vapor from vegetation soil properties, and vegetation properties. The thermal regime is critical by way of affecting plant phenology, developmental phases, growth rates, yield components, and final yield. Growth and development processes follow distinct temperature-response curves displaying a peak or a plateau at what is defined as an optimum temperature. Soil plays a major role in determining the amount and availability of plant nutrients and toxic minerals. Soil properties that determine its mineral effects on plants are mineral content, organic matter content, cation-exchange capacity, sesquioxide content, pH, base saturation, permeability, and moisture-retention capacity.