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Pre-cultivated, nodulated and non-nodulated plants of black alder (Alnus glutinosa) and sea buckthorn (Hippophae rhamnoides ssp. rhamnoides) were grown on different N sources, with and without acidity control. Dry matter yields were lowest when plants were supplied with only NO 3 − and were much greater when NH 4 + was supplied either alone or in combination with NO 3 − as long as the external pH was controlled; the final yields of the N2-fixing plants were relatively low, especially with H. rhamnoides. Without acidity control, yields were greatly reduced in the presence of NH 4 + .

The roots of Hippophae rhamnoides which regularly bear actinomycete induced nodules when growing on Scottish sand dunes have also been found to support an endomycorrhizal association with Glomus fasciculatus. Ultrastructural and cytochemical studies carried out on the indigenous infections of established Hippophae mycorrhizal roots would support the postulate that transport is indeed occurring between the fungal symbiont and the host plant and vice versa in respect of phosphate and carbohydrate. Experiments using various inoculation regimes, demonstrated the significant improvement in the mycorrhizal/nodulated plants compared to the nodulated-only and the mycorrhizal-only plants with respect to plant growth, uptake of phosphate and nitrogenase activity, when grown in a medium poor in combined nitrogen and soluble phosphate. Preliminary work on Alnus and Myrica species growing in Central Scotland indicates that the mycorrhizae associated with these nodulated root systems exhibit a different interaction pattern which may be dependent on habitat type and associated angiosperm species.

SUMMARY: Root-nodules of Elaeagnus spp., Hippophae rhamnoides, Alnus glutinosa and Myrica gale are modified lateral roots. The enlarged cortical cells of an actively growing nodule contain the endophyte in several stages of development, The apical meristem is free from infection but the cells just behind it show a plasmodial stage. In older parts of the nodules, spherical vescles are formed in species of Elacagnus, Hippophae and Alnus and club-shaped bodies in Myrica and from these small, bacteriod-like granules are produced. There is some evidence that granules formed in different host cells fuse in pairs and possess some ability to migrate within the nodule and into the soil. No definite hyphae can be seen in any of the nodules, but well-marked protoplasmic strands or lines of flow are present, particularly in the endophyte of Myrica. The controversial views of earlier writers are discussed, and it is concluded that the nodule organisms are members of the Plasmodiophorales.

Angiogenesis, the formation of new capillaries from pre-existing vascular network, plays an important role in physiological and pathological processes such as embryonic development, wound healing, and development of atherosclerosis. Extension of the circulatory network is also considered to be one the most important factors during cancerogenesis. Inhibition of angiogenesis may lead to inhibition of tumor growth whereas stimulation may improve wound healing. Research achievements suggest the use of plants and their extracts as potential therapeutic agents with pro- or antiangiogenic activity. Since the anticancer and antiangiogenic properties of many phytomedicines have been amply reviewed elsewhere this paper will focus on the treatment of vascular insufficiency in wound healing. Globally accepted herbal drugs are thought to be safe and effective, however, there is a need for more evidence-based confirmation in controlled and validated trials. Among the most frequently studied proangiogenic phytochemicals are ginsenosides from Panax ginseng, beta-sitosterol from Aloe vera, calycosin from Radix Astragali, and extracts from Hippophae rhamnoides L. and Angelica sinensis.

Fruits are one of the most important sources of phenolic compounds in our diet. Many of these compounds exhibit a wide range of biological activities, especially antioxidant activity. The objective of this study was to determine the composition and antioxidant activity of phenolic compounds found in fruit juice obtained from buckthorn, flowering quince, rowanberry and hawthorn. Hydroxycinnamic acids (neochlorogenic and chlorogenic acid) and procyanidins were the main phenolics in rowanberry juice. The highest level of flavonols (quercetin derivatives) was found in sea buckthorn. All juices showed strong free-radical scavenging activity against ABTS•+ radicals and ferric reducing ability measured by the FRAP method. The strongest antioxidant activity was found in rowanberry juice, but the lowest was measured in hawthorn and sea buckthorn juices.

THE study of nitrogen-fixing symbiosis has been mostly confined to legumes. Other symbiotic associations are known, including members of at least four1,2, possibly five3, families of higher flowering plants, and one bryophyte4. The root nodules of Alnus, Myrica and Hippophae appear to contain lower fungi5, but the symbiont responsible for those of Casuarinaseems ill-defined. The leaf nodules of the Rubiaceae contain bacteria6, and the liverwort carries the blue-green alga Nostoc in exterior sacs in the thallus4.

THE three genera comprising the Elaeagnaceae, namely, Elaeagnus, Hippophae and Shepherdia have been known for some time to bear root nodules; but it is only within the past few years that the physiological significance of these structures has been rigorously investigated. Previously, the main interest had been cytological. Nodules of Hippophae1,2 and Shepherdia3 have recently been shown, by growth experiments and by tests with nitrogen-15, to be able to fix nitrogen.

Biogenic interglacial deposits intercalated between two complexes of glacial deposits one and a half miles (2 km.) south-west of Hatfield and near Stanborough, two miles (3 km.) north-east of the first site, are shown to be of Hoxnian age. The lower parts of the deposits represent late-glacial and early interglacial conditions, with Hippophae scrub and birch woodland, with marls forming in a shallow pool, which contained an abundant fauna and flora. The upper parts of the deposits show a more organic infilling of the pools and represent a later part of the interglacial with silver fir present. The presence of a Hoxnian interglacial deposit within the sequence of glacial deposits in the vale of St. Albans establishes the fact that both Lowestoft and Gipping glaciations are represented there.