Abstract

                                Low germination in mangosteen seeds has been the experience of nurserymen in all lands. To improve this a series of studies has been undertaken at the Government Fruit Station, Kallar (Madras) during the past few years. Blossom, biological and pollination studies on that station have revealed that mangosteens can set and mature fruit without the aid of pollination i. e., parthenogenetically, which fact also explains the absence of any horticultural varieties of the fruit. This feature is mainly due to the fact that the flowers are all hermaphrodite with sterile male organs. The segments in the mature fruit do not also all contain seeds; and among those that have seeds, only a few possess well- developed and plump seeds. Because of the incidence of a physiological disease, called gambog, which is typified by the exudation of a yellowish liquid on the rind, pulp and seed of the fruit, it was thought that even the few plump seeds might have their germination capacity adversely affected by the gambog. The testing of these various classes of seeds in different media was one of the iterns of work taken up at Kallar with the object of improving the germination percentage and to secure the maximum number of healthy and robust seedlings. These have shown that the well-developed, plump, and healthy seeds when sown under normal nursery bed conditions in November 1942 gave germination percentage of 30. In a separate trial, similar a seeds free of gambog recorded a germination percentage of 40, while those with signs of gambog incidence on the arils gave only 32-5% germination. The ill-developed leathery seeds were found useless, as none produced a seedling.

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