Effect of the Kinetin on Development of Immature Detached Spike of Cynodon dactylon Under Salt Stress and Normal Conditions

The reproductive development stage is a crucial stage in plant life to study the potential of plant yield. Salt tolerance in this stage is desirable to obtain a stable and high yield. A Cynodon dactylon population from America (Cyn3, London Univ. Collection), was suitable to study the detached immature inflorescence in booting stage on liquid medium. The detached inflorescenes were cultured on a liquid medium prepared with or without various supplements of NaCl (0 to 2%) and kinetin concentrations. The sequence of morphological events of spike development in vitro, and the effects of NaCl on spikelet opening, embryo sac growth, fertilization and caryopsis development were studied. The liquid medium supplemented with 10-7 M kinetin resulted in natural caryopsis development. Supplementing NaCl to the liquid medium had deteriorating effects on the embryo sac development and resulted in the production of abnormal caryopses. The abnormal caryopses were smaller in diameter with a more fragile pericarp. However, a small number of spikelets grown in liquid medium, supplemented with low salt concentration up to 5%, produced normal caryopses and germinated well on soaked filter paper in petri dishes at appropriate conditions.