3种野牡丹属植物杂交特性

野牡丹属(Melastoma L.)植物具有异型雄蕊，大多数种类有较高的观赏价值。为了培育该属植物杂交种并探讨野牡丹属异型雄蕊的功能差异，以多花野牡丹( M. malabathricum)为母本，毛菍( M. sanguineum)、地菍( M. dodecandrum)为父本，统计父本异型雄蕊授粉后的座果率、种子饱满率与萌发特性，并采用形态鉴定法比较杂交子代与父母本自交子代的形态差异。结果表明，毛菍长花药授粉多花野牡丹所得种子饱满率显著高于毛菍短花药，而地菍长短花药之间差异不显著；同一父本异型雄蕊所得种子的发芽率和发芽指数差异不显著；多花野牡丹与毛菍具有更高的杂交亲和性，其中毛菍长花药授粉所得座果率高达100％，所得种子发芽率达到75.33％。杂交后代的叶脉数与母本一致，均为5脉；多花野牡丹与地菍杂交子代株型皆呈匍匐型，叶形指数是其测定的有效指标，变异系数高达47.23％；多花野牡丹与毛菍杂交子代株型均为直立型，株高呈现较明显的杂种优势，超高亲植株率达到80％。

Hybridization characteristics of 3 species of Melastoma

The species of Melastoma L. have heteromorphic stamens and most are of high ornamental value. In order to breed new hybrids and investigate the different functions of heteromorphic stamens by crossbreeding, M. malabathricum was chosen as female parents, M. sanguineum and M. dodecandrum as male parent. The fruit set, plump seed rate and seed germination were measured, with stigmas pollinated by long and short stamens of male parent, respectively. Furthermore, morphological differences between hybrids and self-bred progenies were observed. It was discovered that the plump seed rate of the combination pollinated by M. sanguineum long stamens was significant higher than that by its short ones, while there was no significant difference in M. dodecandrum. In addition, seed germination percentage and germination index were not affected by the pollens of heteromorphic stamens from the same father. A higher cross-compatibility was obtained between M. malabathricum and M. sanguineum, with 100%fruit set and 75.33% seed germination percentage for those pollinated by long stamens. All of the offspring had 5 leaf veins which were similar to M. malabathricum. The offspring, produced by M. malabathricum and M. dodecandrum, was creeping, and leaf index, with 47.23% coefficient of variation, was regarded as an effective way to determine their morphological characteristics. While the offspring by M. malabathricum and M. sanguineum was erect, and there was an obvious heterosis in the hybrids, with 80%hybrids higher than self-bred progenies in plant height.