Asymbiotic seed germination of Phalenopsis Blume orchids after hand pollination

Abstract

Seven commercial hybrids of Phalaenopsis were included in an asymbiotic germination experiment. Plants differed in size and color of flowers and number of inflorescences and flowers. A total of 109 flowers were included of which 60 or 55% were cross-pollinated and reciprocally pollinated. Seed capsules developed on 46 (76.7%) fertilized flowers. Of these, 38 (82.6%) produced seeds as a result of 19 combinations of cross crossing and 19 combinations of reciprocal crossing. Seeds were surface sterilized using 1.6% dichloroisocyanuric acid and inoculated in Petri dishes on commercial media Sigma P1056, in two repeats. There were 23.7% contaminated Petri dishes with seeds after sterilization. The highest average percentage of protocorms (43.1%) developed in cross crossing of plants 3x7, which statistically significantly differed (p < 0.001) from all other combinations of cross crossing except cross crossing 2x6 (30.6%). Crossing 2x6, 1x6 (8.1%) and 1x5 (5.5%) overlap and there were no statistically significant differences between them. There were no statistically significant differences among all of the remaining crossings. There was an overlap of groups among combinations of cross crossing with small flowers x big flowers and reciprocal crossing of big flowers x small flowers. In successful crossing combinations, first plants with two leaves and one or two roots developed only 80 days after seed inoculation on media. Plant no. 4 with the smallest green-yellow flowers was not compatible with any test plants. Seed capsules without seeds developed when plant 4 was a female plant and flowers just fell off when plant 4 was a male plant.