THE NODULAR MYCORRHIZAE OF PODOCARPUS ROSPIGLIOSII

Podocarpus is a genus of southern hemisphere and tropical conifers which are often important timber trees in their respective ranges. Nodular short-roots were early noted as being similar in gross aspect to legume nodules, and it was inferred that they are Rhizobium-bearing symbiotic structures which fix atmospheric nitrogen. In histological section the nodular short-roots of the Venezuelan species Podocarpus rospigliosii were shown to contain endotrophic mycorrhizae. In a Koch's Postulates test, a fungus isolated from Podocarpus induced the formation of nodular structures on aseptic seedlings. A Nitrogen¹⁶ test was negative for fixation of atmospheric N₂. Recent work in New Zealand has shown comparable histology in other species of the genus. The mycorrhizae may be important in forestry practice, though not as a source of nitrogen.     

Biflavones from the genus Podocarpus

A new biflavonoid, podocarpusflavanone, has been isolated from Podocarpus taxifolia and identified by chemical and spectral data as I-4′,I-5,II-5-trihydroxy-II-4′,I-7,II-7-trimethoxy-I-2,3-dihydro-[I-3′,II-8]biflavone along with other biflavonoids. The distribution of biflavonyl pigments in eight Podocarpus species is outlined.     

Ethnobotanical study and conservation status of trees in the district Sargodha,Punjab, Pakistan

Sargodha district is one of the least studied regions of Pakistan regarding its ethnobotanical values. This paper is the first report related to the documentation and conservation status of the tree species in the Sargodha district, and their folk ethnobotanical uses. An interview base survey was conducted in the study area in 2010-2013. The ethnobotanical data revealed the use of 100 tree species (6 gymnosperms, 94 angiosperms) belonging to 77 genera (6 gymnosperms, 71 angiosperms) and 39 families (4 gymnosperms, 35 angiosperms), with the Fabaceae ranking first with 19 tree species, followed by the Moraceae (12 species). Tree species like Aegle marmelos, Butea monosperma, Diospyrus malabarica, Gmelina arborea, Kigelia africana, Manilkara hexandra, Manilkara zapota, Mimusops elengi, Nyctanthes arbor-tristis, Putranjiva roxburghii, Terminalia arjuna and Terminalia bellerica are not only unique in their medicinal value but also interesting because of their unusual occurrence here. Thevetia peruviana, Cassia fistula, Celtis australis, Delonix regia, Diospyrus malabarica, Grevillea robusta, Haplophragma adenophylum, Jacaranda mimosifolia, Lagerstroemia speciosa, Plumeria rubra, Pterospermum acerifolium, Roystonea regia, Taxodium distichum and Tectona grandis are included among the worth looking ornamental tree species. Capparis decidua, Dalbergia sissoo, Tamarix aphylla, Tamarix dioica, Prosopis cineraria and Ziziphus mauritiana are the most commonly used timber species. Other common ethnobotanical utilization of these trees includes either sheltering or fuel or agricultural uses. Lack of awareness about the potential uses of these species, and particularly ignorance of the concerned authorities, have led to a decline in the population of this precious tree flora. Documentation of this tree flora, and as-sociated indigenous knowledge, can be used as a basis for developing management plans for conservation and sustainable use of this flora in the study area. A well-organized management is critical to restore and conserve this endangered natural resource in the District Sargodha, Pakistan. The immense medicinal and timber value of these tree species make it necessary to promote their conservation to simultaneously alleviate the poverty and improve the socio-economic status of the study area.     

Foliage dynamics, leaf traits, and growth of coexisting evergreen and deciduous trees in a tropical montane forest in Ethiopia

Foliage dynamics of three functional tree types representing major components of the tropical montane evergreen forest in southern part of Central Ethiopia were compared. The species were Podocarpus falcatus (evergreen gymnosperm), Prunus africana (evergreen broadleaf), and Croton macrostachyus (facultative deciduous). The hypothesis examined is that in such tropical trees, endogenous control of foliage dynamics by the leaf life-spans (LLS) is largely dominant over external signals. Crown foliage turnover, leafiness of twigs, LLS, photosynthetic performance, respiration rate, specific leaf area, and relative growth rates of the stems were investigated. Foliage dynamics and leafiness of the twigs were monitored over 2?years while leaf traits were followed over 3?months. The degree of inter and intra-individual synchronization of foliage phenophases was examined to get an estimate of the contributions of endogenous and external signals to the dynamics of the foliages. Autoregression analysis indicated significant influence of the moisture regime on leaf sprouting of Croton and Podocarpus. During pronounced dry periods, new leaves were not developed. Analysis of phenological data using circular statistics revealed that in spite of strong inter-individual synchronization of leaf flush and fall (Podocarpus and Croton), the dynamics of individual parts of the crowns were less synchronized. LLS was independent of climate factors and it had substantial contribution to the control of foliage turnover. Moreover, examination of ecophysiological traits of developing leaves of the studied functional types showed differing patterns with LLS corroborating the ecophysiological characteristics. Although overlaid by fungal infestation, both the foliage and ecophysiological properties of Prunus resemble that of Podocarpus but the former exhibited a shorter LLS and slightly higher metabolic rates. Nevertheless, all species reacted positively to high moisture with respect to stem growth. In spite of largely differing weather conditions of the 2?years, direct competitive advantage of one of the species over the others could not be detected.     

Pestalotiopsis yunnanensis sp. nov., an endophyte from Podocarpus macrophyllus (Podocarpaceae) based on morphology and ITS sequence data

Pestalotiopsis is a common and important plant-associated pathogen and endophyte with wide geographical and host distribution. In an investigation of endophytic Pestalotiopsis species associated with Podocarpaceae in China, a new species Pestalotiopsis yunnanensis was isolated from Podocarpus macrophyllus in Kunming, southwestern China. This new species produced pycnidium-like conidiamata in culture, distinct from its morphologically similar species, P. funereoides, P. funerea and P. thujae, which produce acervuli in manual media and hosts. P. yunnanensis also possesses a greater conidium length/width ratio, and longer apical and basal appendages as its distinguishing morphology characters. Phylogenetic analysis of internal transcribed spacer (ITS) sequences showed that P. yunnanensis is a member of Pestalotiopsis, and is distinct from morphologically similar P. funereoides, P. funerea, and P. thujae, as well as other Pestalotiopsis species. A dichotomous key to 26 Pestalotiopsis species occurring on Podocarpus plants is also presented.     

Water relations of indigenous versus exotic tree species,growing at the same site in a tropical montane forest in southern Ethiopia

The objective of the study was to compare the water relations of two indigenous [Podocarpus falcatus (Thunb.) Endl., Croton macrostachys Hochst. ex. Del.] and two exotic tree species (Eucalyptus globulus Labille., Cupressus lusitanica Miller) growing in the same location in the montane Munessa State Forest, southern Ethiopia. Stem flow was measured with Granier type thermal dissipation probes. Sap flux, normalized per unit sapwood area, and the total sapwood areas of the particular trees were used to estimate daily transpiration. Maximum daily transpiration values (60 kg water) were recorded for Croton when at full foliage. After shedding most of its leaves in the dry season transpiration was reduced to 8 kg per day. Eucalyptus had the next highest transpiration (55 kg), in this case at the peak of the dry season. It transpired 4–5 times more than Podocarpus and Cupressus trees of similar size. Maximum stem flux density was tree-size dependent only in Croton. Diurnal patterns of stem flux indicated that Croton, Eucalyptus and Podocarpus, in contrast to Cupressus, responded more directly to light than to atmospheric water pressure deficit. At high VPD (>1.0 kPa) stem flux reached a plateau in Croton and Podocarpus indicating stomatal limitation. Per unit leaf area Croton had the highest and Podocarpus and Cupressus the lowest daily transpiration rates. In summary, the pioneer tree Croton had the lowest and Podocarpus the highest water use efficiency. The contribution of the study to the understanding of the role of each tree species in the hydrology of the natural forest and the plantations is discussed.     

Differential utilization and ethnobotany of trees in kitulanghalo forest reserve and surrounding communal lands, eastern tanzania

This study documents the utilization aspects and distribution of ethnobotanical knowledge of the local people of Morogoro, Tanzania, as a first step towards sustainable utilization and conservation of tropical woodlands. A total of 133 arborescent species in 31 families was identified of which 69% had a variety of uses. These uses were classified into 12 categories and major uses were charcoal, firewood, medicine, and poles. Most tree species have occasional uses, but a few are exceptionally useful and thus their levels of utilization may far exceed their regeneration and production. The questionnaire survey indicated that 62% of the respondents agreed that traditional medical services were more available than modern services. Utilization surveys indicated that wooden poles are the building material used in 98% of the dwellings and storage structures, wild foods were useful for food security especially during drought years, and high quality timber trees have been depleted in the forest because of earlier exploitation by pit-sawing. The distribution of ethnobotanical knowledge indicated that much of the relevant ethnobotanical and utilization information was held by more aged members of the society and hence there is a clear need to capture this knowledge before it is lost. This study has shown that resources are defined by use and culture, and some components of ethnobotanical knowledge have potential for the sustainable management of miombo woodlands.     

Norditerpene dilactones from Podocarpus saligna

Rimuene and nubigenol have been identified in Podocarpus saligna for the first time, and the structures of three new norditerpene dilactones, salignones K, L and M, isolated from this species have been elucidated.     

The cytotoxic norditerpene dilactones of Podocarpus milanjianus and Podocarpus sellowii

The cytotoxic norditerpene dilactones nagilactone F and its new congener nagilactone G have been isolated from the bark constituents of Podocarpus milanjianus and Podocarpus sellowii. The diterpenes totarol, 19-oxototarol and macrophyllic acid were also isolated.     

Post-fire spread of alien plant species in a mixed broad-leaved forest of the Insubric region

How do tree species regenerate and which ecological conditions are required after forest fire in the Insubric region of the Alps? Are indigenous stand-forming tree species resistant over the invasion of alien plant species after such a disturbance? We addressed these questions in a case study in the Swiss canton of Ticino. In April 2006, a surface fire with severe intensity burnt a forest area of 55 ha on a south-facing slope (400-800 m.a.s.l.). The dominant trees in the investigated area were chestnut (Castanea sativa Mill.), beech (Fagus sylvatica L.) and deciduous oaks (Quercus spp.) mixed with tree species of intermediate height. Vegetation data were collected in May and August 2009 by systematic sampling. Resprouting of the survived trees and generative regeneration were analysed by counting vegetative shoots from sprouting stools, of seedling age, height and damage rate, respectively. Different vegetation structures related to low or high fire intensity were clearly visible three years after the forest fire, creating various habitats for both new invaders and seedlings of the stand-forming trees. The dominant chestnut was the only tree species that regenerated effectively by sprouting from stools. Seedlings of the stand-forming trees grew in high abundance under shadow conditions close to their mother trees which provided the seed source. In contrast, pioneer trees invaded patches where full light was available. Under such conditions the two main woody alien plant species, Ailanthus altissima and Robinia pseudoacacia, grew in high abundance. Due to the different ecological requirements of indigenous and alien tree seedlings, not any interaction between the two groups was detected.     

Tree population studies in low-diversity forests, Guyana. II. Assessments on the distribution and abundance of non-timber forest products

Comparisons between two forest localities were undertaken to assess the potential availability of non-timber forest products (NTFPs) within the low-diversity forests of Guyana. Information on the abundance and distribution of tree species, and local and national ethnobotanical surveys were used classifying species into five categories (timber, construction, technological, edible and medicinal). A total of 152 species were recorded from the two localities; covering 236 different uses, 33 known commercial timber species and 106 species with potential non-timber product utilization. The most important plant families with the highest number of uses at both localities were Leguminosae (sub-families Caesalpinioideae and Mimosoideae), Arecaceae, Bombacaceae and Chrysobalanaceae, although these families were not the most abundant families at both localities. At both forest localities eight tree species represented over 50% of all the trees. At Kurupukari three species, each with more than three identified NTFPs, represented over 20% of the trees.Potential utilization of NTFPs are discussed in accordance with species richness, tree density, the number of different uses per species, and the percentage of trees represented by each utilizable species. Considering the constraints on the future potential commercialization of NTFPs, two scenarios for the extraction of NTFPs are discussed. Within relatively species-rich forest types the high diversity of products provides potentially viable multiple-species extractionism. In contrast, in low-diversity forest types, typical of the Guiana Shield, one or two NTFP species frequently represent over 50% of the canopy trees, and therefore substantially increase the potential sustainable extraction for single-species harvesting. It is suggested that these low-diversity types of forest are prioritized for conservation on the basis of ensuring future utilization, refuge, of non-timber forest products.     

First record of L-quebrachitol in Allophylus edulis (Sapindaceae)

Allophylus edulis, commonly called ‘Chal chal’, is a member of the Sapindaceae occurring in the Uruguayan and Brazilian native flora. During the phytochemical analysis of two Chal chal specimens from two well-differentiated geographical zones (Assis, São Paulo, Brazil, and Santa Lucía, Canelones, Uruguay), considerable amounts of l-quebrachitol were isolated from both samples. The isolation was carried out from the ethanolic twig extracts obtained by maceration of both vegetal samples. White easily distinguishable crystals were mechanically separated, washed, and characterized by 1D and 2D NMR experiments and by MS data. Such techniques confirmed that the crystals isolated from sources collected in both countries resulted in the same compound, l-quebrachitol, a natural product not previously reported for this species and one that has been investigated as a sugar substitute for diabetics. Worthy of note, the content of l-quebrachitol in A. edulis may be the chemical basis to explain its ethnobotanical uses, since infusions of this plant are used to treat diabetes in the practice of local traditional medicine.     

Phenolic diterpenoids of podocarpus ferrugineus and other podocarps

19-Hydroxyferruginol and 19-acetoxyferruginol, two new naturally occurring phenolic diterpenoids, have been isolated from the heartwood of Podocarpus ferrugineus. Totarol and its derivatives have been obtained from Podocarpus affinis, P. falcatus, P. koordersii, Dacrycarpus vieillardii and Decussocarpus comptonii and podocarpic acid from Falcatifolium taxoides.     

Development and characterization of microsatellite markers in sawih tree (Duabanga moluccana Blume) using ISSR-suppression PCR techniques

Duabanga moluccana (or locally known as sawih) is an indigenous fast growing tropical tree species that confers various advantages for the timber industry and for planted forests development. In this paper, we isolated and characterized 8 polymorphic microsatellite markers from the D. moluccana genome using ISSR-suppression PCR techniques. The number of alleles and PIC values ranged from 3 to 8 alleles per locus and from 0.488 to 0.792, respectively. Three microsatellite loci were deviated from Hardy-Weinberg equilibrium (P < 0.05). The transferability rate ranged from 24 to 100 % among the three indigenous tree species tested. This indicates that the newly developed microsatellite markers would be useful tools for population genetic studies on D. moluccana and other indigenous tree species.     

Multilocus sequence analyses reveal several unnamed Mesorhizobium genospecies nodulating Acacia species and Sesbania sesban trees in Southern regions of Ethiopia

Leguminous trees play an important role in agroforestry in Ethiopia, but studies of their rhizobial symbionts are scarce. In earlier studies, we surveyed natural nodulation of native leguminous trees growing in different agro-ecological zones in Southern Ethiopia, isolated 400 rhizobia, and characterized them based on different phenotypic and genotypic methods. In the present study we characterized 18 strains belonging to the genus Mesorhizobium, isolated from nodules of Acacia abyssinica, A. senegal, A. tortilis and Sesbania sesban. Phylogenetic analysis of nearly full-length 16S rRNA gene grouped the test strains into three distinct clades separated from all currently recognized Mesorhizobium species. Three divergent strains formed separate branches while the other 15 strains formed three distinct groups, genospecies I-III. Grouping of the isolates under study based on the house-keeping genes recA, gyrB, rpoB and gltA were consistent and in agreement with that of 16S rRNA. Similarly phylogenetic relationships based on the symbiosis-related genes nodC, nodA and nifH were generally similar to those shown by the core genes, suggesting that these Acacia and Sesbania symbionts have a long history of separate evolution within Mesorhizobium. Cross inoculation experiments demonstrated a large variation in the ability of the test strains to elicit effective nodules. The Sesbania isolates, occupying a distinct clade in the nodC phylogenetic tree, formed effective nodules only with this host legume. The study strongly suggests that this collection of Mesorhizobium strains comprises several new species, and also indicates the role of the symbiotic genes in determining the host range of these bacteria.     

Botanists and their childhood memories: an underutilized expert source in ethnobotanical research

Botanists are an overlooked group of informants in ethnobotanical studies. The aim of this study was to assess their potential as sources of original ethnobotanical information. Wild food plants remembered by Polish botanists from their childhood were freelisted by 71 botanists. The results were compared with several ethnobotanical studies: three from the 21^st century and one from the mid‐20^th century. The botanists listed 123 species (mean of 9.3 species per individual). Although the average number of personal freelists was slightly lower for botanists than for local key informants in two of the other studies (11 and 13, respectively), the total list of species was longer than in any other Polish ethnobotanical study. Two of the ethnobotanical studies supplied richer material on past famine plants, whereas the botanists mentioned many alien plants and plants from urban habitats not mentioned in the ethnographical study. It can be concluded that botanists are possibly the best source of information for studies of contemporary or new uses of plants, but are inadequate for uses that are dying out. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 334–343.     

Genus Ziziphus for the treatment of chronic inflammatory diseases

Natural products and traditional medicine are rich sources for developing therapeutics for chronic inflammatory diseases. However, the way from natural products/traditional medicines to Western pharmaceutical practices is not always straightforward. According to the World Health Organization (WHO), chronic diseases are the greatest threat to human health. 3 of 5 people die due to chronic inflammatory disorders worldwide like chronic respiratory diseases, stroke, cardiovascular diseases, cancer, diabetes, and obesity. Various nonsteroidal anti-inflammatory drugs (NSAIDs) are used to reduce inflammation and pain, but there are many side effects of these drugs' administration. Medicinal plants have therapeutic anti-inflammatory effects with low or no side effects. Ziziphus plant species are generally safe and not toxic to humans. Many studies on the Ziziphus species have shown that their therapeutic properties are attributed to the roots, leaves and fruits. Unfortunately, Ziziphus species from different regions worldwide with anti-inflammatory properties have not been documented in a single review paper. Therefore, it is crucial to establish ethnobotanical knowledge and applications of Ziziphus species against chronic inflammatory diseases. The current article exhaustively reviews phytochemical profile, pharmacological studies, toxicological effects, and ethnobotanical uses of Genus Ziziphus in chronic anti-inflammatory diseases. The present review article also highlights the most promising experimental data on Ziziphus extracts and pure compounds active in clinical trials and animal models of chronic inflammatory diseases. This review would be a valuable resource for contemporary researchers in the field to understand the promising role of the Ziziphus genus in chronic inflammatory disorders.     

Nodule morphology,symbiotic specificity and association with unusual rhizobia are distinguishing features of the genus Listia within the southern African crotalarioid clade Lotononis s.l.

Background and Aims

The legume clade Lotononis sensu lato (s.l.; tribe Crotalarieae) comprises three genera: Listia, Leobordea and Lotononis sensu stricto (s.s.). Listia species are symbiotically specific and form lupinoid nodules with rhizobial species of Methylobacterium and Microvirga. This work investigated whether these symbiotic traits were confined to Listia by determining the ability of rhizobial strains isolated from species of Lotononis s.l. to nodulate Listia, Leobordea and Lotononis s.s. hosts and by examining the morphology and structure of the resulting nodules.

Methods

Rhizobia were characterized by sequencing their 16S rRNA and nodA genes. Nodulation and N₂ fixation on eight taxonomically diverse Lotononis s.l. species were determined in glasshouse trials. Nodules of all hosts, and the process of infection and nodule initiation in Listia angolensis and Listia bainesii, were examined by light microscopy.

Key Results

Rhizobia associated with Lotononis s.l. were phylogenetically diverse. Leobordea and Lotononis s.s. isolates were most closely related to Bradyrhizobium spp., Ensifer meliloti, Mesorhizobium tianshanense and Methylobacterium nodulans. Listia angolensis formed effective nodules only with species of Microvirga. Listia bainesii nodulated only with pigmented Methylobacterium. Five lineages of nodA were found. Listia angolensis and L. bainesii formed lupinoid nodules, whereas nodules of Leobordea and Lotononis s.s. species were indeterminate. All effective nodules contained uniformly infected central tissue. Listia angolensis and L. bainesii nodule initials occurred on the border of the hypocotyl and along the tap root, and nodule primordia developed in the outer cortical layer. Neither root hair curling nor infection threads were seen.

Conclusions

Two specificity groups occur within Lotononis s.l.: Listia species are symbiotically specific, while species of Leobordea and Lotononis s.s. are generally promiscuous and interact with rhizobia of diverse chromosomal and symbiotic lineages. The seasonally waterlogged habitat of Listia species may favour the development of symbiotic specificity.     

Reproductive biology and population structures of Podocarpus falcatus and P. latifolius in southern Gape forests

GELDENHUYS, C. J., 1993. Reproductive biology and population structures of Podocarpus falcatus and P. latifolius in southern Cape forests This study concerns morphological differences of the fruit types of two Podocarpus species in relation to their different population recruitment rates. First, sampling data from the mixed evergreen forests of Gouna and Groenkop in the southern Cape, South Africa, were used to describe the population structures of the two species. Podocarpus falcatus is widely scattered at low density and has a low recruitment rate. Podocarpus latifolius is widespread and common at high density and has a high recruitment rate. Second, the morphology of their fruits and seeds was studied in relation to seed dispersal, predation and germination. The species represent the two basic ‘fruit’ types of the genus. Podocarpus falcatus produces a heavy fruit, but invests mostly in dispersal (with a yellow fleshy pulp or epimatium enclosing the seed) and protective tissue (stony shell or sclerotesta) and very little into endosperm food reserves for the embryo. Podocarpus latifolius produces a light fruit which is composed mainly of dispersal tissue (blackish-purple fleshy receptacle) with protective tissue (thin leathery epimatium without woody sclerotesta) and food reserves for the embryo. The structure of the P. falcatus fruit is related to adaptation for protection during seed dispersal by bats. The stony sclerotesta delays germination for about one year and thereby causes the exposure of the seed to high post-dispersal predation by rodents and bushpig. Seedling recruitment is low. In contrast birds and baboons eat the receptacle of the P. latifolius fruit and discard the seed undamaged. Less protective tissue is required. Seeds germinate within two to four months and recruitment is high. The structural differences of the two fruit types also have predictive value for the relative success of the different sections of the genus. Section Afrocarpus (to which P. falcatus belongs) and related sections have relatively restricted geographic distributions. Section Eupodocarpus (to which P. latifolius belongs) and related sections have wide distributions.     

Morphometric traits and sexual dimorphisms do not strongly differentiate populations of Zeravshan juniper (Juniperus seravschanica Kom.) in Kyrgyzstan

Intra- and among-population variations of Juniperus seravschanica were morphologically examined in eight populations originating from elevations of 1300–2200 m a.s.l. in Kyrgyzstan. Eleven traits of needles and cones were studied on 70 vouchers. In addition, height, diameter, stem form, and sex of 172 trees were recorded in the field in order to test whether male trees invest more in vegetative growth than females and if sex ratio is shaped by (limited) environmental resources. Morphological differences among populations were small, but needle length, width and thickness were statistically different. However, differences based on needle traits were independent from geographical, altitudinal and environmental distances. In sharp contrast to studies in other Juniperus species, sex ratio in J. seravschanica was strongly female biased (3.5 females : 1 male). Moreover, no correlation between the habitat conditions and the sex ratio was detected, suggesting that within the altitudinal range of this species, females occur more frequently. This has implications for sustainable use and the conservation of J. seravschanica populations. It is likely, that due to the higher investment of male individuals in vegetative growth males are more exploited than females. An average effective population size of 70% of the respective census suggests that conservation measures and non-selective logging regimes are required to allow reproduction and a natural regeneration of this species.