炭角菌科部分类群的生物地理学研究(英文)

与肉质真菌相比,大多数炭角菌科真菌的子实体结构和质地使其在自然环境中保持长久,不易腐变,这有利于记录该科采集物的分布信息,基于过去长达25年对该科的深厚工作积累,使我们有可能对其进行地理分布的研究。     

Micropropagation and hairy root culture of Ophiorrhiza alata Craib for camptothecin production

An efficient system was developed for the in vitro micropropagation and hairy root culture of Ophiorrhiza alata Craib for camptothecin (CPT) production. Shoot multiplication on leaf and node explants from germinated seeds of O. alata was successful on half-strength Murashige and Skoog medium supplemented with varying amounts of kinetin and α-naphthaleneacetic acid. Node explants grown in vitro were successfully infected by Agrobacterium rhizogenes TISTR 1450 for the establishment of hairy root culture. The amount of CPT in various parts of O. alata was analyzed by HPLC. The accumulation of CPT in transformed hairy roots was twice that in soil-grown plants (785 ± 52 and 388 ± 32 μg/g dry wt, respectively). In the presence of a polystyrene resin (Diaion HP-20) that absorbed CPT, the CPT content in the culture media increased sevenfold compared with controls (1,036 and 151 μg per 250 ml medium, respectively). These results enable the feasible production of CPT of O. alata by means of a cell culture strategy. These measures can help safeguard the plant from extinction.     

Genetic diversity and species-specific PCR-based markers from AFLP analyses of Thai bananas

A large amount of banana genetic resource has been found in Thailand which is believed to be one of the centers of its origins. To assess genetic diversity and determine genetic relationships of edible bananas in Thailand, 110 accessions of banana species and cultivars collected from villages and natural locations were investigated. UPGMA clustering of numerical data from Amplified Fragment Length Polymorphism (AFLP) patterns showed two large groups which corresponded to genome designations of Musa acuminata (AA) and Musa balbisiana (BB), the known ancestors of most edible cultivars. The AFLP data suggested that among Thai bananas, AA and AAA cultivars were closely related to M. acuminata subsp. malaccensis, while some of ‘B’ genome contained ones closely related to wild M. balbisiana in Thailand and some may have been imported. Eight species-specific PCR-based primer pairs, generated from the AFLP results clearly identify ‘A’ and ‘B’ genomes within cultivars and hybrids. The analyses were useful to readily and easily infer progenitors of these cultivars and pronounce wide genetic diversity of the bananas in Thailand.