FURTHER OBSERVATIONS ON THE "CONTRACTION STAGE OF MICROSPORE" IN RICE (ORYZA SATIVA L. )

In a study of the rice mjcrospore, anthers from the same spikelet were used in the following methods of preparing anther squash slides: 1 ) fresh anther squash slides were prepared using distilled water, 2) fresh anther squash slides were prepared using aceto-carmine, 3 ) anthers were fixed in Carney's fluid for 24 hours and transferred to 70% ethyl alcohol for 15 minutes before being stained with aceto-carmine,and 4 )anthers were fixed in 3 % glutaraldehyde for 1 hour and rinsed twice with phosphate buffer before being stained with aceto-carmine.The experiment showed that contraction is not a normal feature of the microspore in its formative process but rather an effect of the fixatives on the young microspores. Hence, contraction could not be designated as part of the developmental stfge of the microspore, as reported in the literatures. Carncy's flujd caused Jess contraction at tetrad stage while glutaraldehyde showed less contraction at young microspore stage. No contracted microspores were observed in Treatment 1 when the squash slides were examined immediately. Plasmolysis occasionally appeared in some microspores in Treatment 2 .