Simulação gráfica do crescimento de plantas de milho

Abstract

The computer graphic simulation can be used to understand plant growth and development influenced by biotic or abiotic parameters. The main simulation purposes are: (i) to predict plant agronomic characteristics when its submitted to different climatic, environmental, and physical factors; (ii) to analyze the influence of these factors in plant growth and development, yield and dry matter production and; (iii) to analyze the economical viability of some crop in an specific crop production system. The computer simulation is an important tool for agronomists, enabling evaluations of plant responses without conducting field experiments or even collecting experimental data in the field. The development of a maize plant (appearance of a phenological stage) depends mainly of the temperature accumulation. Thus, the maize phenological stages were simulated using vector graphics and internet programming tools, generating an animation of the plant growth and development. The study was conducted in two phases: (i) field experiment and; (ii) analysis of the collect field data, creation of programming routines and reproducing plant canopy by drawings using specific computer technique. The first phase consisted in conducting a field experiment to determined measurements of maximum leaf width and length, plant height and taken digital photos during plant growth and development. The second phase consisted in the vector representation of each leaf, leaf area index and plant height during different crop phenological stages (obtained through the processing of digital photos). Data of mean daily temperature (obtained through a portable weather station), temperature accumulation and internodes length were organized in a relational database table, to simplify the programming routines. These routines, written in PHP and SVG languages, allowed the generation of an animation of a single or several maize plants, according to some pre-selected parameters (phenological stage, maximum plant height, row or plant spacing, soil water deficit, etc.). The technique used in this work allows the simulation of plant growth and development from a computer connected to the internet, since the files created for the simulation are stored in the web server.