Seed Production on Detached Culms of Pearl Millet × Elephantgrass Hexaploid Hybrids
Five nutrient solutions were evaluated in the greenhouse to determine which solutions would allow detached culms of Pennisetum to produce seed. The genotypes tested originated from the hybridization of Pennisetum glaucum L. (Pearl millet) × P. pennisetum Schum. (elephantgrass). The solutions were water, Hoagland's, sucrose, sucrose + hydroxyquinoline sulfate (HQ), and Hoagland's + sucrose + HQ. Neither the water nor the Hoagland's solution supported high seed set. Although the sucrose solution enhanced seed production, the seeds were low in weight and did not germinate well. The best nutrient solutions were 2% sucrose + 0.02% HQ or Hoagland's + 2% sucrose + 0.02% HQ. The four genotypes used differed substantially in seed production, but all produced seed, with germination >25%. This result indicates that the cut-culm technique is a possible way of getting recurrent restricted phenotypic selection seed in Pennisetum hexaploid hybrids.