Diazotrophs provide the only biological source of fixed atmospheric nitrogen in the biosphere. Although they are the key player for plant-available nitrogen, less is known about their diversity and potential importance in arid ecosystems. We investigated the nitrogenase gene diversity in native and agricultural desert soil as well as within root-associated microbiota of medicinal plants grown i...

8-beta-Hydroxypimar-15-en-19-oic acid (1), taxodione (2), 6,7-dehydro-8-hydrotaxodone (3), quercetin-3-O-beta-D-glucopyranoside (4), and shikimic acid (5) were isolated from the leaves of Taxodium distichum L. (Rich.) for the first time. Previously reported compounds [beta-sitosterol (6), isorhamnetin (7), quercetin (8), isorhamnetin-3-O-alpha-arabinofuranoside (9), quercetin-3-O-a-arabinofuran...

A method is described whereby amyloplasts from immature barley (Hordeum distichum L.) endosperm could be separated into two populations of large and small amyloplasts at all stages of development. The small amyloplasts had more amylopectin than the large at early stages, but by 60 days after anthesis, the large had the greater proportion of amylopectin. Starch synthetase activity was associated...

Tracer gas studies and oxygen uptake measurements have shown that pressurized gas transport improves oxygen supply to roots in the wetland tree species Taxodium distichum L. Rich. (Taxodiaceae), Betula pubescens J.F. Ehrh. (Betulaceae), and Populus tremula L. (Salicaceae), but not in Acer pseudoplatanus L. and Ilex aquifolium L., which are found in drier habitats. In the deciduous tree species ...

From gametophytes of Rhizogonium distichum have been isolated the biflavone dicranolomin and five triluteolins. Two of the triluteolins, which were named rhizogoniumtriluteolin and distichumtriluteolin, were new compounds; their structures have been elucidated spectroscopically.