Musa chunii Hakkinen,a new species （Musaceae） from Yunnan,China and taxonomic identity of Musa rubra

The center of diversity of the genus Musa （Musaceae） is in Southeast Asia, a region not studied in detail and where new species and varieties continue to be reported. A new wild banana species, M. chunii Hakkinen from Yunnan, China is described and illustrated based on observed morphological characteristics in the field. This extremely rare new species was only found in Tongbiguan Nature Reserve, Dehong District, West Yunnan. A key to M. chunii and related taxa is provided. In addition, critical notes regarding M. rubra Kurz identity are given.     

Musa aurantiaca (Musaceae) and its intraspecific taxa in India

Musa aurantiaca Baker (Musaceae) is distributed from northeast India, Tibet to northern Myanmar. In the present study its intraspecific taxa are thoroughly investigated. Two new varieties are described and illustrated based on live plants in the field: M. aurantiaca Baker var. homenborgohainiana Gogoi and M. aurantiaca Baker var. jengingensis Gogoi. A key to the varieties of Musa aurantiaca Baker and closely related taxa is also provided.     

人为干扰对小果野芭蕉群落生物量及多样性的影响

采用标准木法和回归分析法（乔木层）研究了小果野芭蕉群落在演替吕不同的压力条件下生物量和多样性的变化,结果显示,小果野芭蕉的侵入在正常情况下对群落生物量的影响并不显著,但由于人为干扰,可以明显地降低群落生物量。人为干扰是小果野芭焦群落长期保持在一个种群数量较大,物种多样性指较低和重要值较大的状态。轮歇丢荒地小果野芭蕉的侵入和迅速发展,是群落恢复演替过程中一种正常的途径。因此保持小果野芭蕉群落不受人为干扰是使其沿正常演替途径恢复的一种可行方法。     

Comprative Studies on Karyotypes of Some Species of Hemerocallis (Liliaceae)

Some species of Hemerocallis were cultivated in the campus of Futan University, including the evergreen H. aurantiaca Baker. The original plant of H. aurantiaca was introduced from Zhangzhou, southeastern Fukien Province. The karyotype formula of H. aurantiaca is 2n=33=12m+9sm+3st+3T+6m(sat). The karyotype differs from those of summer-green or evergreen H. fulva (k(2n)=33=3M+21m+6sm +3T) and H. fulva var. kwanso (K(2n)=33=3M+l8m+6sm+3st+3T). The vouchers are kept in FUS.     

A new species of the wild banana genus,Musa (Musaceae), from Borneo

A new species of wild banana, Musa bauensis Häkkinen & Meekiong, is described and illustrated. It is from the Bau limestone area, Sarawak, East Malaysia.     

Genome constitution for Musa beccarii (Musaceae) varieties

Borneo is a large island in Southeast Asia. It is divided politically into three parts: the kingdom of Brunei on the north central coast; the Malaysian states of Sarawak and Sabah to the west and east; with Kalimantan of Indonesia making up the larger par…     

香蕉RAPD分析初步研究

比较了不同提取方法对香蕉植株不同部位组织提取 DNA的质量及其 PCR扩增结果 ,对香蕉 RAPD分析中引物种类和浓度 ,复性温度 ,d NTPs,Taq DNA聚合酶浓度 ,热循环数等因素进行了比较影响分析。结果表明 ,虽然改良的 SDS法、CTAB法和 PVP法提取的植株嫩叶和吸芽 DNA提取量和纯度各不相同 ,但其 PCR扩增结果基本相同 ;相同克隆不同植株的 DNA其 PCR扩增结果也基本相同 ;建立了适合香蕉大规模 DNA多态性分析 RAPD反应体系 :2 5 μL反应液中 ,含 1倍缓冲液 ,0 .2 m Md NTPs,0 .3 2 p M随机引物 ,IUTaq酶 ,2 0 ng模板 DNA;反应循环数为 45 ,热循环条件为 94°C,1 min;3 7°C,1 min;72°C,1 .5 min;之前为 94°C,5 min;之后为72°C,1 0 min。在筛选的 2 49个随机引物中 ,有 1 8个在 7个品种上都能扩增出 3～ 1 0条比较清晰条带。     

Musa chunii Hakkinen, a new species (Musaceae) from Yunnan,China and taxonomic identity of Musa rubra

The center of diversity of the genus Musa (Musaceae) is in Southeast Asia, a region not studied in detail and where new species and varieties continue to be reported. A new wild banana species, M. chunii Hakki-nen from Yunnan, China is described and illustrated based on observed morphological characteristics in the field. This extremely rare new species was only found in Tongbiguan Nature Reserve, Dehong District, West Yunnan. A key to M. chunii and related taxa is provided. In addition, critical notes regarding M. rubra Kurz identity are given.     

广东大蕉分类位置的探讨

本文从形态特征,减数分裂,染色体配对以及核型分析等三个方面探讨了广东大蕉在属内的分类位置问题,根据１５个形态特征的比较评分,染色体组同源性和核型特征的分析结果,广东大蕉应属ＢＢＢ类型。它的学名应为Ｍｕｓａ ｂａｌｂｓｉａｎａ Ｃｏｌｌａ（ＢＢＢｇｒｏｕｐ）。     

Domestication, genomics and the future for banana

BACKGROUND: Cultivated bananas and plantains are giant herbaceous plants within the genus Musa. They are both sterile and parthenocarpic so the fruit develops without seed. The cultivated hybrids and species are mostly triploid (2n = 3x = 33; a few are diploid or tetraploid), and most have been propagated from mutants found in the wild. With a production of 100 million tons annually, banana is a staple food across the Asian, African and American tropics, with the 15 % that is exported being important to many economies. SCOPE: There are well over a thousand domesticated Musa cultivars and their genetic diversity is high, indicating multiple origins from different wild hybrids between two principle ancestral species. However, the difficulty of genetics and sterility of the crop has meant that the development of new varieties through hybridization, mutation or transformation was not very successful in the 20th century. Knowledge of structural and functional genomics and genes, reproductive physiology, cytogenetics, and comparative genomics with rice, Arabidopsis and other model species has increased our understanding of Musa and its diversity enormously. CONCLUSIONS: There are major challenges to banana production from virulent diseases, abiotic stresses and new demands for sustainability, quality, transport and yield. Within the genepool of cultivars and wild species there are genetic resistances to many stresses. Genomic approaches are now rapidly advancing in Musa and have the prospect of helping enable banana to maintain and increase its importance as a staple food and cash crop through integration of genetical, evolutionary and structural data, allowing targeted breeding, transformation and efficient use of Musa biodiversity in the future.     

Physical mapping of the 18S-25S and 5S ribosomal RNA genes in diploid bananas

Fluorescent in situ hybridisation (FISH) was used to determine the number and distribution of the 18S-25S and 5S rDNA sites on mitotic chromosomes of 6 wild and 2 edible diploid (2n=22) accessions belonging to the two banana species, Musa acuminata and M. balbisiana. FISH with the 18S-25S probe resulted in signals on one pair of chromosomes, the position of signals corresponded to the secondary constriction at the end of a short arm. The intensity of labelling was different between the homologues and the larger site corresponded to a larger secondary constriction. This labelling pattern was observed consistently in all genotypes. On the other hand, differences in the number of 5S sites were observed between the accessions. While in some of the wild seeded species, the 5S rDNA was localised on two pairs of chromosomes, hybridisation signals appeared on three pairs of chromosomes in other wild accessions. Quite unexpectedly, only five sites of 5S rDNA were reproducibly observed in the two vegetatively propagated diploid edible cultivars, Pisang Mas and Niyarma Yik, evidence for structural heterozygosity. A dual colour FISH showed that in all accessions, the satellite chromosomes carrying the 18S-25S loci did not carry the 5S loci. The results demonstrate that molecular cytogenetics can be applied to Musa and that physical cytogenetic maps can be generated. This revised version was published online in July 2006 with corrections to the Cover Date.     

Function of Host and Fungal Metabolites in Resistance Response of Banana and Plantain in the Black Sigatoka Disease Pathosystem (Musa spp. –Mycosphaerella fijiensis)

The host–pathogen interactions of Musa spp. and Mycosphaerella fijiensis were investigated in order to determine the function of secondary metabolites within the pathosystem of the Black Sigatoka disease. The pentaketide metabolites flaviolin, 2-hydroxyjuglone, juglone and 2,4,8-trihydroxytetralone (2,4,8-THT) of the pathogen were identified. The concentration of 2,4,8-THT was significantly increased by application of the synthetic compound tricyclazole and by natural activators extracted from the intercellular space of leaf tissue of resistant Musa cultivars. When inoculated host plants were treated with tricyclazole, extensive necrosis of both susceptible and resistant Musa cultivar leaves were observed. Plant defence mechanisms of resistant Musa cultivars were first detected as an activation of phenylalanine–ammonia lyase and the subsequent accumulation of post-infectional substances which blocked fungal growth. These results indicated the bivalent importance of 2,4,8-THT for host-specific reactions, depending on its concentration at different stages of pathogenesis. Early activation of fungal 2,4,8-THT metabolism by resistant Musa cultivars caused necrotic micro-lesions and elicitation of post-infectional defence reactions leading to incompatibility between pathogen and host plant; growth of the fungus on susceptible cultivars caused necrotizing doses of 2,4,8-THT only after the establishment of a compatible interaction and development of typical symptoms at late stages of pathogenesis.     

香蕉植株内生细菌群落多态性研究

采用平板法对香蕉(Musa nana)植株的内生细菌进行分离纯化,并采用细菌脂肪酸法进行鉴定。结果表明,从香蕉的健康植株和感病植株中共分离得到内生细菌21属24种。从健株分离得到9种内生细菌,其中根、茎和叶分别分离到6种、2种和8种内生细菌。从病株分离得到15属17种内生细菌,其中根、茎和叶分别分离到3种、11种和6种。香蕉健株根部的内生细菌含量最高,达5.195×106cfu g-1,下部叶片内生细菌的含量最低,仅为30 cfu g-1;香蕉病株茎部内生细菌的数量显著高于其他部位,达1.05×107cfu g-1。这说明香蕉在不同生长状态下,其内生细菌的种类和数量存在多样性。     

Efficacy of RAPD,ISSR and DAMD markers in assessment of genetic variability and population structure of wild Musa acuminata colla

Physiology and Molecular Biology of Plants - North east India is considered as one of the major biodiversity hotspots worldwide and centre of origin of several plant species including Musa. Musa...