Plant pigment dyes for pollen staining

บทคัดย่อ

The pollen-staining efficiency of natural dyes has been tested only in plant tissues and chromosomes, but still has not been investigated in pollen. The organic compounds of pollen are different from those of other plant structures. Therefore, this research aims to select plants and solvents that are suitable for natural dye extraction for pollen staining. The flowers of Clitoria ternatea L. and Delonix regia (Bojer ex Hook.) Raf. and pericarps of Hylocereus undatus (Haw.) Britton & Rose, and Garcinia mangostana L. were extracted with distilled water or 95 percent ethyl alcohol at a ratio of 1:10 (weight/volume) and soaking for 72 h. Then the samples were filtered, evaporated, and vacuum freeze-dried. Pollen of Hibiscus rosa-sinensis L. was used to test the efficiency of natural dyes. The results showed that the natural dye extracted with distilled water from flowers of D. regia and pericarps of H. undatus had efficiency similar to safranin O for pollen staining, in regard to color of the stain and also transparency. In addition, the shape and size of exine sculpturing, ornamentation, aperture, and pollen wall thickness were seen more clearly than in unstained pollen. On the other hand, the natural dyes were extracted from these plants with 95 percent ethyl alcohol have low to moderate efficiency in pollen staining. Thus, it is not suitable for use as a solvent for pigment extraction.