稻属分类的现状及存在问题

The current taxonomy and perplexity of the genus Oryza (Poaceae)

稻属OryzaL .是禾本科中重要的植物类群 ,该属含 2 0余种 ,广泛分布于全球热带和亚热带地区。未来水稻育种的重大突破还将有赖于对稻属基因库中丰富种质资源 ,特别是野生稻资源的利用和开发。由于稻属植物在农业生产中的重要作用 ,引起了众多的植物分类学家、遗传学家、育种学家和分子生物学家的广泛研究。稻属自Linnaeus于 1 75 3年建立以来的 2 0 0多年中 ,无论在物种的数量和分类系统上都产生了很大的变化。多位学者对稻属的属以下等级和种间的分类都做了详细的工作 ,对稻属现代分类系统的建立起到了重要的作用。Roschevicz ( 1 931 )对稻属全面深入的研究为后来的稻属系统分类奠定了基础。Sharma&Shastry ( 1 965 )建立的稻属分类系统在很大程度上受了Roschevicz( 1 931 )工作的影响 ,对属以下种以上的分类等级也处理得较合理 ,但是他们对稻属的分类定义较为广泛 ,包括了好几个如今已不放在稻属的物种。Vaughan ( 1 989)对全球的稻属标本进行了较为全面的查证和研究 ,他建立的稻属系统不仅在属的界定上更为合理 ,而且对稻属中各物种的形态变异、地理分布和种间的关系 ,都有更清楚的描述。遗憾的是 ,Vaughan ( 1 989)采用的属下等级———“复合体”(complex) ,不符合国际植物命名法规 (ICBN)的规定?

The genus Oryza L. is one of the most important plant groups in the grass family (Poaceae), which includes more than 20 species and is distributed in tropics and subtropics of the world. The future breakthrough of rice breeding relies greatly on the exploration and utilization of rich germplasm in the rice genepool, particularly the wild rice species. Because of its significant importance in the agricultural production, the genus Oryza has attracted much attention of many taxonomists, geneticists, breeders, and molecular biologists for various kinds of research. During the last two hundred and fifty years since the first description of the genus Oryza by Linnaeus, great changes have taken place in the genus in terms of number of species and taxonomic status. Many taxonomists have made extensive researches on species circumscription and taxonomic ranking at the subgenus level, which was essential for the establishment of the modern taxonomic systems of Oryza. The taxonomic system established by Roschevicz (1931) based on his comprehensive and detailed studies on plant specimens and literature provided an important foundation for the modern taxonomy of the genus Oryza. Sharma & Shastry (1965) offered a taxonomic system of Oryza, which was essentially influenced by that of Roschevicz. This system treated subgenus rank properly, but their definition of Oryza was in a much wider sense and several species in this system have been excluded from the current Oryza. Vaughan (1989) extensively studied and compared Oryza samples from all over the world and provided a taxonomic system including updated data such as morphological variation, geographic distribution, and genome constitution of each species. This system not only adopted a reasonable generic definition, but also provided a good reference of species relationship. Unfortunately, the subgenus rank 'complex' used by Vaughan (1989) does not have any legitimate standing in the International Code of Botanic Nomenclature (ICBN). Lu (1999) summarized the major taxonomic studies of previous authors including new species published in Oryza over the past ten years, and proposed an Oryza taxonomic system with 3 sections, 7 series and 24 species. We provided in this paper the most updated studies of the Oryza species and suggested a revised version of Oryza taxonomy with a morphological key to species. We also discussed the existing problems in the taxonomy of the genus Oryza.