Dr Jeremy Whish1, Dr. Fernanda Dreccer1
1CSIRO, St Lucia Brisbane, Australia
Biography:
Jeremy Whish is a principal research scientist in the Agricultural Systems Program of Agriculture and Food. He is currently using simulation modelling and field research experiments to investigate farm management strategies and the role of pulses across the grain production areas of Australia.
Abstract:
Understanding the phenological development of a crop is critical to matching genetics to the environment. Growth keys have traditionally been used as a systematic way of classifying crop development over time. One of the most used methodologies is the BBCH scale that uses a decimal code to divide the plant lifecycle into 10 main stages. An alternative approach often used on pulses separates the lifecycle into two stages, vegetative and reproductive. However, the indeterminant development of pulses provides a unique challenge to clearly identify the start and end of specific developmental stages. Unlike many determinant crops it is not uncommon to observe pulses producing flowers, immature pods, mature pods and leaves at the same time or for the primary stem to lose apical dominance. Thus, preventing the main stem from being the most advanced continuous measure of plant development.
To address this issue GRDC’s National Pulse Agronomy project has focussed on adapting the BBCH scale for peas to specifically suit the indeterminant nature of chickpea and lentil. The new key allows for overlapping stages and looks at development across the whole plant following flowering. This captures the importance of pods developing on primary branches and prevents the problems of the main stem’s development being out of sync with the bulk of the plant.
The key has been tested and modified over the last 3 years and used by the team on over forty thousand field observations. The use of clearly identifiable stages, that are visual, has improved consistency in data recording and provided greater confidence in describing how the environment influences the development of chickpea and lentil across Australia.