Jaume and I have a new paper accepted by Journal of Experimental Botany about the leaf economics spectrum (LES) in rice, a domesticated grass. LES is an ecology(-physiological) concept described leaf traits covariation (or more specifically, ‘traits trade-offs’), that is the fast-growing species always combined with low leaf investment (e.g. carbon, Nitrogen), and, in contrast, the slow-growing species combined with high investment. Over the past decades, the LES has received widespread attention; however, most of those studies based on natural wood species. The productivity of annual crops, such as rice and wheat, are typically higher than natural plants due to the human selections and their specific growth environment. A detailed investigation of LES in crops is needed to fill this important gaps in our understanding of LES, and finally, we did. We started the project in 2015 when I was working on my Ph.D. thesis in Jaume’s lab, and we wrote the paper last year when I was at the University of Sydney as a ‘freedman’. In this project, we constructed a rice leaf traits database through collecting data from the published literature (as shown in below figure).
Using this dataset, we firstly compared the leaf traits correlations in rice to the global leaf economics spectrum (Glopnet) database, which showed that leaf traits correlations in rice differed significantly from the Glopnet. In summary, the rice appears higher light-saturated photosynthetic rate (Asat) than natural species at a given leaf nitrogen content, and the Asat and leaf nitrogen content are more sensitive to changes of leaf mass per area across rice genotypes than across natural species. To exploit the mechanisms behind those differences, we investigated the variation of leaf anatomical, biochemical and physiological traits of rice and their role on the traits trade-offs. It seems that high rate of N allocated in Rubisco, and the extremely sensitive of mesophyll conductance to leaf nitrogen are two major reasons.