Autotetraploidy, both natural and/or induced, has potential for genetic improvement of various crop species including that of medicinal importance. Tinospora cordifolia (Willdenow, 1806) Miers, 1851 ex Hooker et Thomson, 1855 and T. sinensis (Loureiro, 1790) Merrill, 1934 are two diploid species, which are dioecious, deciduous and climbing shrubs with high medicinal importance. Among the three methods used for induction of polyploidy by colchicine treatment, it was cotton swab method which successfully induced the polyploidy in both species. The morphological and cytogenetical features of the synthetic tetraploids were compared with their diploid counterparts. The tetraploids were morphologically distinct from diploid plants. They exhibited larger organs, such as stem, leaves, inflorescence, fruits, flowers and seeds. The tetraploids were characterized by the presence of low quadrivalent frequency and high bivalent average. Unequal distribution of chromosomes at anaphase I was found in 60% cells. The present study provides important information on the superiority of autotetraploids as compared to diploid counterparts in both species.

中文翻译：

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两种Tinospora Miers物种的秋水仙科四倍体的诱导和评估，1851年。

天然和/或诱导的同源四倍体具有对包括药用重要性在内的各种作物物种进行遗传改良的潜力。Tinospora cordifolia（Willdenow，1806）Miers，1851摘自Hooker et Thomson，1855和T. sinensis（Loureiro，1790）Merrill，1934是两个二倍体物种，它们是雌雄异株，落叶和攀缘灌木，具有很高的药用价值。通过秋水仙碱诱导多倍体的三种方法中，棉签法成功地诱导了两种物种的多倍体。比较了合成四倍体的形态学和细胞遗传学特征及其对应的二倍体。四倍体在形态上不同于二倍体植物。它们表现出较大的器官，例如茎，叶，花序，果实，花朵和种子。四倍体的特征在于低四价频率和高二价平均值的存在。在60％的细胞中发现I期后期的染色体分布不均。本研究提供了有关同四倍体与二倍体对应物相比在两个物种中优越性的重要信息。