Assessment of cereal stand structure and its changes during the growing season

Abstract

Historical evolution of approaches used for the assessment of the cereal stand structure development is presented. Weaknesses and strengths of these approaches are discussed that are based on: - dividing of cereal yield into yield components and growth analysis, - modular concept of plant growth, - use of laws of plant population biology in order to explain autoregulation and compensation in stands.The presented methods are assessed with respect to labour intensity and possibilities of utilization of obtained information. Other possibilities of diagnostics of the cereal stand state and structure using a current level of knowledge and new technologies enabling to determine spectral characteristics of the stand by areal sensing are outlined. Based on the character of processes influencing the stand structure, the growing season of cereals was divided into the three parts:1. vegetative, including the period from emergence till the end of tillering (BBCH 10-29),2. generative, including the period of stem elongation and heading (BBCH 30-59),3. reproductive, including anthesis, grain formation and maturation (BBCH 60-99).To optimize the stand structure, data necessary for decision making in cereal crop management practices were proposed for the above listed development stages.