Genetic variation in leaf chlorophyll content of Jatropha curcas L.

Jatropha curcas L. (jatropha) has recently received great attention for its utilization in biofuel production, rehabilitation of wasteland and rural development. Knowledge of plant physiology is important for breeding and agronomy and photosynthesis is one of the key physiological processes on Earth. We investigated the genetic variation in leaf chlorophyll content of jatropha. Using a high-throughput methodology, 257 accessions were screened under field conditions. Measurements were performed at three locations repeatedly on several dates during the vegetation period. Genetic variation of this trait was large among the genotypes tested showing a high potential for adaptation to changing environments. We found genotypes with consistent high level and low level of leaf chlorophyll content as well as genotypes that showed cross-over interactions across environments. Leaf chlorophyll content was associated with flowering level, but the level of association with seed mass was low. Measurements of leaf chlorophyll content were associated with environmental stress. We conclude that leaf chlorophyll content is a viable trait to assess the physiological status of a plant in the field during the vegetation period. It might serve for the detection of stress symptoms, but agronomic applications have to be calibrated for each specific genotype.