Characterizing Wheat Root Branching Using a Markov Chain Approach

Root system architecture is an important factor influencing plant exploitation efficiency for edaphic resources. However, the difficulty to predict the distribution of laterals severely hampers root system architecture analysis. A Markov chain approach was adopted to characterize the succession of laterals along the mother root axis, using data collected from studies with contrasting P supplies and with different degrees of compaction of growth substrate. The main findings were that successive lateral roots were generally separated by a minimum inter-lateral distance, and neither compaction of root medium nor the phosphorus availabilities affected the distance and succession pattern of lateral roots along the main roots. The results from the Markov chain model were consistent with the findings by other researchers using different approaches. Further study with similar approach but considering local variation of soil chemical and physical conditions should give more insight into the plasticity of root system architecture.

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