Two cyclopeptides from the seeds of Annona cherimola

Bioassay-guided fractionation of cytotoxic of methanol extract of the seeds of Annona cherimola provided two novel cyclic peptides, cherimolacyclopeptide E (1) and cherimolacyclopeptide F (2), which exhibited significant cytotoxic activity against the KB (human nasopharyngeal carcinoma) cell culture system. The peptide 1 and 2 were elucidated by MS/MS fragmentation experiments using a Q-TOF mass spectrometer equipped with an ESI source, extensive 2D NMR analyses and chemical degradation.     

Cherimolacyclopeptide D, a novel cycloheptapeptide from the seeds of Annona cherimola

In a chemical investigation of the seeds of Annona cherimola, a natural cyclic heptapeptide, cherimolacyclopeptide D, were isolated and purified by HPLC with three known cyclic peptides, cherimolacyclopeptides A, B and C. The structure was established by various analyses including MS/MS fragmentation, spectroscopic and chemical evidences.     

Interpretation of triose phosphate isomerase isozymes in the cherimoya (Annona cherimola Mill.)

Detailed interpretation of triose phosphate isomerase (TPI) isozymes in seed plants has been restricted to only a few species. Three sets of TPI bands are regularly observed in the cherimoya(Annona cherimola), a primitive angiosperm. The slowest, set I, is expressed as one or three bands; the second-slowest set II, as one or two bands; and the fastest, set IV, as one or three bands. A faint set III, just cathodal to set IV, is detected rarely with overstaining. Set IV bands are expressed in macerated extracted pollen but not in pollen leachate. Dissociation-reassociation experiments reveal that the set II bands are heterodimers involving, in part, the enzymes involved in the set I bands. These data combined with those from full-sib progeny analysis lead us to propose a three-locus model to explain the TPI isozyme banding patterns in cherimoya. Sets I and IV consist of the allelic products of individual, single loci. Sets I and II occur in the cytoplasm. Set IV occurs in organelles. Set II isozymes are the intergenic heterodimers of the locus coding for set I and the locus coding for set III. Our results reported here are contrasted with the TPI isozyme patterns known for other vascular plants and suggest that the locus coding for set III may be a duplication of very ancient origin.This work was supported, in part, by funding from the Elvenia J. Slosson Endowment Fund.     

Archaeological evidence of cherimoya(Annona cherimolia Mill.) and Guanabana(Annona muricata L.) in ancient Peru

Archaeological Evidence of Cherimoya (Annona cherimolia Mill.)and Guanabana (Annona muricata L.)in Ancient Peru. Economic Botany 58(4):509-522, 2004. The results of this study confirm the presence of both guanabana and cherimoya in ancient Peru. Our evidence consists of linguistic data and botanical remains of plants that were found in archaeological contexts, as well as ceramic phytomorphic representations of the fruits.

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Evidencias arqueológicas de chirimoya (Annona Cherimolia Mill.) YGuanabana (Aannona muricata L.)en el Antiguo Perú

Résumé  Con el presente trabajo se demuestra, que tanto la guanábana como la chirimoya han sido conocidas y utilizadas en el antiguo Perú. Las evidencias consisten en datos linguistícos y restos botánicos de dichas plantas que han sido encontrados en contextos arqueológicos y representaciones en cerámica de sus frutos.

     

Phylogenetics of Annona cherimola (Annonaceae) and some of its closest relatives

Annona cherimola is a woody perennial species in the Annonaceae family that produces edible fruits and has economic importance in several regions of the world with subtropical climates. Together with other 10‐12 species, A. cherimola belongs to the section Atta of the Annona genus with a center of origin in Central America and the Caribbean. Species of the section Atta produce soft skin ripe fruits with raised areoles bounded by recessed furrows. Annona cherimola is the only species of the section naturally found in the Andean region of South America. Currently, no information is available at the molecular level on the phylogenetic relationships of most of the species of Atta and closely related sections in Annona. In order to fill this gap, in this work a phylogenetic approach was performed using five coding and non‐coding plastid DNA regions, to determine the phylogenetic relationships between A. cherimola and other related species included in Atta and other sections of the genus. The results obtained support recent studies that demonstrated the likely Mesoamerican origin of A. cherimola based on biogeographical analysis with SSR markers, rather than the previously considered South American origin hypothesis. In addition, the species belonging to the Atta section did not show monophyly. Finally, A. cherimola and A. pruinosa seem to be phylogenetically close species and additional studies are needed to discern the relations between them.     

Micropropagation of juvenile and adult Annona squamosa

A micropropagation system for Annona squamosa L. (Sugar Apple) using hypocotyls of seedlings and nodal cuttings from 3-year-old plants was developed. Shoot proliferation was achieved with Woody Plant Medium supplemented with BA. Silver thiosulphate was added at 0.5 mg l^–1 to control leaf abscission. Rooting was obtained when subcultured shoots were preconditioned for 2 weeks in medium with 10 g l^–1 activated charcoal before treatment with 43 µm NAA or 39 µm IBA. Rooting was improved when galactose was used instead of sucrose in the rooting medium. The rooted plantlets were acclimatised successfully.Abbreviations NAA naphthaleneacetic acid - IBA indolebutyric acid - MS Murashige & Skoog Medium - WPM Woody Plant Medium - NN Nitsch Medium - Juv juvenile explant - Adu adult explant     

Arbuscular mycorrhizae formed by Penicillium pinophilum improve the growth, nutrient uptake and photosynthesis of strawberry with two inoculum-types

Penicillium pinophilum was isolated from the soil in a commercial strawberry field. The strain readily formed arbuscular mycorrhizae (AM) with the roots of strawberry 'Zoji' (Fragaria x ananassa Duch. CV.) when plants were inoculated with either fresh cultured hyphae or root/soil mixtures. Fresh hyphae, however, resulted in higher amounts of colonization than root/soil inoculum. Compared with uninoculated strawberries, inoculation increased plant dry weight by 31%, as well as nitrogen content (47%), phosphorus content (57%), and photosynthetic rate (71%). AM inoculation also shortened the blossom and ripening date by 3 and 4 days, respectively. This is the first report of a P. pinophilum strain resulting in mycorrhiza with strawberry roots. The significant advantages of this strain are that it is easy to culture and inoculation of plants results in significant growth benefits that may be useful in strawberry production.     

Segregation distortion of isozyme loci in cherimoya (Annona cherimola Mill)

The allelic segregation of 13 isozyme loci in hand-fertilized heterozygous cherimoya trees (Annona cherimola Mill.) has been studied. We analyzed 63 locus x progeny combinations and found non-Mendelian segregation in 12 cases. The sequential Bonferroni method revealed only eight cases of non-Mendelian segregation; these have been investigated with several chi-square tests to discover what processes were involved. Gametic selection appears to be the main contributor, although zygotic selection seems also to play a part.     

Effect of vesicular-arbuscular mycorrhizae on the growth and yield of rice-stubble cultured soybeans

Summary Inoculation with vesicular-arbuscular (VA) mycorrhizal fungiGlomus fasciculatus, G. mosseae, G. etunicatus orAcaulospora scrobiculatus, increased plant dry weight and seed yields of pot-grown soybean plants in sterilized soil. Inoculation with a mixture ofG. fasciculatus, G. mosseae andG. etunicatus, orG. fasciculatus alone, increased seed yields and other agronomic traits of soybean plants grown in a no-tillage, rice-stubble field.     

Vesicular arbuscular mycorrhizae in floating wetland mat communities dominated by Typha

Low levels of vesicular arbuscular mycorrhizae were present in floating mats dominated by clones of Typha angustifolia L., T. x glauca Godr., and T. latifolia L. Floating mats composed of rhizomes (underwater-ground stems with high starch accumulation), roots, decaying organic matter, and wind deposited soil, easily supported human activities. The majority of roots isolated from the root cores were connected to Typha rhizomes. Tests employing the gridline intersect method, intensity, spore counts and most probable number (MPN) were used to define the level of colonization. Mycorrhizal colonization from the T. angustifolia and T. x glauca clones averaged 4 to 5%, while the T. latifolia clone averaged 13%. When colonization was encountered, intensities varied from a high of 3.0 to a low of 0.4 on a sclae of 0 to 4. Although arbuscules were not found, abundant hyphae, vesicles and spores indicated that presumed facultative associations occurred between the vesicular arbuscular fungi and the indicated that presumed facultative associations plant communities found on floating mats. The mycorrhizal fungi identified from these communities in cluded Glomus albidum Walker & Rhodes, G. caledonium (Nicol. & Gerd.) Trappe & Gerdemann, G. etunicatum Becker & Gerdemann, and G. microcarpum Tul. & Tul. Spore counts ranged from 16 to 76 spores per gram dried organic soil. The recolonization ability of VAM propagules by way of a most probable number bioassay with maize yielded numbers that ranged from zero to 96 propagules per gram soil, with G. etunicatum the only species recovered.     

喀斯特典型地区烟管荚蒾AM真菌多样性研究

烟管荚蒾是喀斯特地区灌木丛的主要组成植物。以茂兰喀斯特森林为采样地点,对烟管荚蒾AM真菌进行了分离、鉴定与多样性分析,并对优势菌种进行初步的接种研究。结果表明:烟管荚蒾根系的菌根侵染率为82.1%,从根际土壤分离到AM真菌2属16种,球囊霉属(Glomus)7种,无梗囊霉属(Acaulospora)9种。优势种为根内球囊霉(Glomus intraradices)、皱壁无梗囊霉(Acaulospora rugosa)和刺无梗囊霉(A. spinosa)。优势菌种接种紫花苜蓿(Medicago sativa),促生作用明显,并显著提高了SOD、POD和CAT酶活性。该研究对于探讨喀斯特地区AM真菌的多样性与独特性,筛选优良的宿主植物和与之高效共生的AM真菌具重要意义。     

Arbuscular mycorrhizal morphology in crops and associated weeds in tropical agro-ecosystems

Morphological types of arbuscular mycorrhizae (AM) in crops and associated weeds were examined in agro-ecosystems. In total, 48 plant species (8 crops and 40 weeds) belonging to 43 genera in 18 families were examined. The number of plant species with Arum-type AM was higher than those with Paris-type AM in the examined plants. AM association was absent in 6 weeds, and the average colonization rate was 62.64% in crops and 52.92% in weeds. AM morphology has been reported in 2 crops and 21 weeds for the first time. The influence of plant identity on AM morphology was also analyzed by arranging the examined plants in a current plant phylogenetic scheme. This analysis showed there was a lack of relationship between plant classification and AM morphological type. Actually, the colonization types were not distinguished at the plant family level, but were mostly distinguished at the species level.     

Host plant differences in arbuscular mycorrhizae: Extra radical hyphae differences between an invasive forb and a native bunchgrass

Arbuscular mycorrhizae affect grassland plant community composition and host plant nutrient uptake, and can mediate shifts in competitive outcome between plant species. Centaurea maculosa, an invasive forb from Eurasia, dominates more than 4 million hectares in the Rocky Mountain region of North America. We examined the role of AM for phosphorus (P) acquisition from a distant source for C. maculosa and Festuca idahoensis, a native bunchgrass. Plants were grown individually in pots divided by a barrier that either excluded plant roots and AM hyphae, or only plant roots. In the half of the pot without a plant, 1 of 3 P treatments was applied: no P, phosphate rock (PR) or triple superphosphate (TSP), applied at a rate of 144 mg P kg^–1 soil. After 14 weeks of growth, C. maculosa was twice as large as F. idahoensis, and neither species biomass was affected by barrier type. Phosphorus fertilizer, and especially PR, moved across the barrier to the plant side of the pot. Tissue P concentration for C. maculosa was highest with the PR treatment, and was not affected by the barrier type. In contrast, F. idahoensis tissue P concentration did not vary with barrier or P treatments. There was more AM extra radical hyphae (ERH) associated with C. maculosa than F. idahoensis, suggesting that C. maculosa provides more carbon for the AM fungi, resulting in greater ERH production, ERH soil exploration and potential for soil nutrient pool exploitation. Although not tested in this study, differences between host plants may be the result of different physiological characteristics of the host plant or differences in AM fungal species that colonize the invader, with different fungal species accessing P from different distances.     

Interactive effects of mycorrhizae and a root hemiparasite on plant community productivity and diversity

Plant communities can be affected both by arbuscular mycorrhizal fungi (AMF) and hemiparasitic plants. However, little is known about the interactive effects of these two biotic factors on the productivity and diversity of plant communities. To address this question, we set up a greenhouse study in which different AMF inocula and a hemiparasitic plant (Rhinanthus minor) were added to experimental grassland communities in a fully factorial design. In addition, single plants of each species in the grassland community were grown with the same treatments to distinguish direct AMF effects from indirect effects via plant competition. We found that AMF changed plant community structure by influencing the plant species differently. At the community level, AMF decreased the productivity by 15–24%, depending on the particular AMF treatment, mainly because two dominant species, Holcus lanatus and Plantago lanceolata, showed a negative mycorrhizal dependency. Concomitantly, plant diversity increased due to AMF inoculation and was highest in the treatment with a combination of two commercial AM strains. AMF had a positive effect on growth of the hemiparasite, and thereby induced a negative impact of the hemiparasite on host plant biomass which was not found in non-inoculated communities. However, the hemiparasite did not increase plant diversity. Our results highlight the importance of interactions with soil microbes for plant community structure and that these indirect effects can vary among AMF treatments. We conclude that mutualistic interactions with AMF, but not antagonistic interactions with a root hemiparasite, promote plant diversity in this grassland community. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Occurrence and importance of mycorrhizae in aquatic trees of New South Wales,Australia

Vesicular arbuscular mycorrhizal (VAM) infection was found in KOH-cleared and lactophenolblue-stained roots of Salix babylonica, Melaleuca quinquenervia and Casuarina cunninghamiana. These are all trees growing on creeks and river banks, in stationary or slowly flowing fresh or brackish waters in swamps, creeks, drains and channels, and in seepage areas of New South Wales, Australia. Larger and older roots lacked VAM infection in the inner cortex, probably due to suberisation of cells, and the endophyte was restricted to the epidermal layers. Spores and sporocarps of the VAM fungi Glomus fasciculatus, G. mosseae, Sclerocystis rubiformis, Gigaspora margarita and an unidentified Scutellospora sp. were wet sieved and decanted from aquatic sediments and soils. The presence of similar VAM fungal spores in the aquatic sediments and terrestrial soil suggests that they probably enter the aquatic sediments through run off from the land ecosystem. All three plants formed vesicular arbuscular (VA) mycorrhizae almost exclusively in the marshy, periodically inundated soils, but the same plant species formed endo-/ ectomycorrhizae when growing in soil with higher redox potentials (E _h). Salix and Melaleuca tree roots possessed both VAmycorrhizae and ectomycorrhizae. VAM roots of Casuarina were equipped with both N-fixing Frankia nodules and proteoid roots. VAM endophytes did not invade nodular cortical tissues, suggesting the presence of an exclusion mechanism which needs further study. The highest VAM infection was found in nodulated specimens. Free-floating roots growing in water close to the banks were non-mycorrhizal but were mycorrhizal in the bottom-rooting state. VAM spore number and mycorrhizal infection seem to be associated with redox-potential, i.e. lower at sites such as swamps, water or sediments with lower E _h values than in terrestrial soils with higher E _h values. A relationship between soil moisture gradient and VAM infection pattern became apparent from the study of a C. cunninghamiana transect on a creek embankment, i.e. typical vesicles and arbuscules were found in roots from drier soils, there was a lack of arbuscules in relatively wet soils but large lipid-filled intracellular vesicles were present, and typical vesicles and arbuscules were absent in flooded creek beds where roots were associated with coenocytic intercellular hyphae with abundant lipid droplets. The importance of VA mycorrhiza, ectomycorrhizae, N-fixing root nodules and proteoid roots at the land-water interface is discussed with reference to the use of these trees as pioneering species for stabilising river and stream banks, reducing erosion, windbreaking, and as a long-term and inexpensive means of achieving biological control of aquatic weeds by shading waterways.     

In vitro organogenesis from leaf explants of Annona squamosa Linn

Multiple shoot formation was induced from excised leaf explants of Annona squamosa Linn. (custard apple) seedlings on a Murashige and Skoog basal medium containing benzylaminopurine and kinetin. Various auxins in combination with the above medium produced callusing of the explants. In an investigation of environmental factors affecting shoot induction it was seen that the maximum number of shoots were obtained using the leaf base with petiole at a temperature of 27°C and a light intensity of 1000 lux. Roots were initiated erratically when individual shoots were treated with an auxin and then transferred to an auxin free medium. The process of the development of adventitious buds in leaf culture was analysed histologically.NCL Communication No. 3104.     

Glaucacyclopeptide A from the seeds of Annona glauca

The seeds of Annona glauca furnished two cyclopeptides one of which is novel. The structure was elucidated on the basis on mass spectrometry, 2D NMR methods and amino acids analysis.     

Localization of the yellow pigment formed in roots of gramineous plants colonized by arbuscular fungi

Summary Many plants form yellow coloured roots when colonized by arbuscular mycorrhizal (AM) fungi. In maize, a yellow pigment is first visible as small droplets in parenchyma cells of roots in the vicinity of arbuscules, 3–4 weeks after mycorrhizal colonization. During the course of the development of the plants, the yellow pigment spreads all over the cells of the cortex (with the exception of the exodermis) and of the endodermis, whereas the other stelar elements remain uncoloured. Other gramineous plants (wheat, barley, millet) show the same pattern of pigment formation. In contrast, the deposition of this pigment is not detected in roots ofTagetes, garden bean, onion, or leek. Weak yellow fluorescence is also seen in the fungal structures, particularly in the arbuscules of the investigated probes. This is, however, clearly different from the intense yellow colour of the pigment formed in root cells of grasses. The yellow pigment is even detected in such cells which are never colonized by fungal structures (e.g., endodermal cells). A major constituent of the yellow pigment of AM-colonized root cells has been identified as a carotenoid with 14 carbon atoms and two carboxylic groups and termed mycorradicin. This carotenoid is likely deposited in the vacuoles of root cells as a result of the colonization specifically by arbuscular fungi.     

Dual mycorrhizal colonization of forest-dominating tropical trees and the mycorrhizal status of non-dominant tree and liana species

The contribution of mycorrhizal associations to maintaining tree diversity patterns in tropical rain forests is poorly known. Many tropical monodominant trees form ectomycorrhizal (EM) associations, and there is evidence that the EM mutualism contributes to the maintenance of monodominance. It is assumed that most other tropical tree species form arbuscular mycorrhizal (AM) associations, and while many mycorrhizal surveys have been done, the mycorrhizal status of numerous tropical tree taxa remains undocumented. In this study, we tested the assumption that most tropical trees form AM associations by sampling root vouchers from tree and liana species in monodominant Dicymbe corymbosa forest and an adjacent mixed rain forest in Guyana. Roots were assessed for the presence/absence of AM and EM structures. Of the 142 species of trees and lianas surveyed, three tree species (the monodominant D. corymbosa, the grove-forming D. altsonii, and the non-dominant Aldina insignis) were EM, 137 were exclusively AM, and two were non-mycorrhizal. Both EM and AM structures were observed in D. corymbosa and D. altsonii. These results provide empirical data supporting the assumption that most tropical trees form AM associations for this region in the Guiana Shield and provide the first report of dual EM/AM colonization in Dicymbe species. Dual colonization of the Dicymbe species should be further explored to determine if this ability contributes to the establishment and maintenance of site dominance. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.