Chromosome numbers of Jatropha curcas L.: an important agrofuel plant

Abstract

Chromosome numbers were determined in five populations of the agrofuel physic nut plant (Jatropha curcas L.). Somatic chromosome numbers were counted from root-tip cells of four individuals per population and all had 2n=22 chromosomes, corresponding to the diploid level (x=11). The chromosomes are small (ca. 1 to 2 µm), meta or submetacentrics. The present results are in line with literature and indicate that all J. curcas populations examined so far are diploid. This lack of variation in chromosome number contrasts with the high variability in other characteristics. From the plant breeding viewpoint, the fact that all populations analyzed are diploid and have the same chromosome number is an advantage for planning crosses and obtaining hybrids.