Associations between yield, intercepted radiation and radiation-use efficiency in chickpea

Abstract

Relationships between yield, biomass, radiation interception (PARint) and radiation-use efficiency (RUE) have been studied in many crops for use in growth analysis and modelling. Research in chickpea (Cicer arietinum L.) is limited, with variation caused by environment and phenological stage not adequately described. This study aims to characterise the variation in chickpea PARint and RUE with phenological stage, line and environment and their interactions, and the impact of this variation on yield. Chickpea lines (six desi and one kabuli) previously identified as varying for yield, competitive ability, crop growth rate and phenology were compared in four environments resulting from a combination of two sowing dates and dry and irrigated water regimes. Yield varied from 0.7 to 3.7 t ha–1. Line, environment, phenological stage and the interactions line (G) × environment (E) and environment × stage affected both RUE and PARint. Line × stage interaction also affected RUE. High PARint and RUE were associated with high yield, but the interaction between environment and phenological stage dictated this relationship; higher PARint and RUE were observed in irrigated environments. Some environment × phenological stage combinations resulted in no significant associations, particularly before flowering in dry environments. These results emphasise the importance of understanding the effects of G × E on capture and efficiency in the use of radiation and have implications for growth analysis, modelling and breeding.