Morphologische waarnemingen aan rijstplanten, gegroeid bij verschillende lengten van de photoperiode

After a literature study the morphology is described of rice plants grown under short (12 h) and long (18 h) photoperiods. The varieties Nero di Vialone, Kameji, Fortuna, Tjina and Karang Serang were used. Effects of photoperiod on leaf growth were examined. In Nero di Vialone tillering was studied. An active tillering period was distinguished in which buds developed rapidly into tillers; thereafter tillering stopped and some tillers died back. The photoperiod had no effect on tiller number. When tillering continued after floral initiation had occurred in the main culm, the time of flowering of the tillers was irregular. Renewed tillering was found in some widely spaced Kameji plants after floral initiation.

In Nero di Vialone buds at the base of the main culm and of the principal tillers normally developed into tillers, although some buds elongated, and did not grow out. The buds of flowering plants of Nero di Vialone and Kameji were found to contain panicle primordia.

The direct and indirect effects of photoperiod on elongation of stem, particle, sheath of the uppermost (flag)leaf, peduncle and awns are described.