Plant

A phylogeny based on nrITS1 and trnL-F sequences resolves the Lejeunea tumida species group polyphyletic with individuals belonging in two clades either side of the basal-most node within Lejeunea. It is impossible for the Lejeunea tumida species group to be more polyphyletic and still be attributed to the same genus under the existing generic classification. A simulation-based approach to testing the null hypothesis of group monophyly rejects this at the P < 0.01 level of significance. Bayesian tests find very strong support for polyphyly, given the data. The monophyly of L. tumida s.s. + L. colensoana is fully supported; however, although Lejeunea tumida s.s. is nested within L. colensoana, this position is not supported. Both L. oracola and L. rhigophila are resolved as monophyletic. Whereas there is moderate support for the monophyly of L. rhigophila, there is no support for the monophyly of L. oracola. Neither is the monophyly of L. oracola + L. rhigophila supported in Bayesian or parsimony analysis.

Transfer of 137 Cs in the soileplant/lichenereindeer food chain was studied in central (Østre Namdal) and southern Norway (Va˚ga˚) during 2000e2003. Reindeer from these areas have been continuously subjected to countermeasure application since the 1986 Chernobyl accident. In both areas no decline in 137 Cs concentrations was detectable in reindeer slaughtered in autumn since 1995, or in reindeer slaughtered in winter since 1998e1999. Seasonal differences in 137 Cs concentrations in reindeer have been less pronounced in recent years, with 137 Cs concentrations occasionally higher in autumn than in winter. Soil-to-plant 137 Cs transfer was significantly higher in Østre Namdal than in Va˚ga˚. Climatic influences on lichen growth and abundance, and on soil properties that influence the availability of 137 Cs for plant uptake, are hypothesized to have a larger impact on long-term transfer of radiocaesium in the soileplant/ lichenereindeer food chain than has been previously observed. Journal of Environmental Radioactivity 83 (2005) 231e252 www.elsevier.com/locate/jenvrad 232 L. Skuterud et al. / J. Environ. Radioactivity 83 (2005) 231e252 233 L. Skuterud et al. / J. Environ. Radioactivity 83 (2005) 231e252 234 L. Skuterud et al. / J. Environ. Radioactivity 83 (2005) 231e252 248 L. Skuterud et al. / J. Environ. Radioactivity 83 (2005) 231e252

Ethnobotanical approaches to the study of Mediterranean food plants offer novel ways for analyzing and preserving traditional knowledge and agrobiodiversity in the Mediterranean area. This article highlights our strategy to increase the awareness within traditional knowledge systems and encourage the continuous evolution of it, avoiding the loss of substantial parts of the local cultural and biological diversity. The strategy is part of a broader stream of thought, which does attempt to disseminate information locally in a multitude of ways, e.g. through a range of publications in rural or urban zones, to people with or without formal education, to children or the elderly. This article is a very personal account of the experience of the authors, but there is an urgent need to assess the impact of such activities on a broader level, and, also, to reassess the impact researchers have on the communities. Our clear impression in all field sites has been that the simple fact that such traditional knowledge systems are the focus of scientific investigation are an essential element of giving renewed sociocultural value to such knowledge and that activities like the ones described here are of great interest to the communities we worked in.

Two experiments were conducted to evaluate the allelopathic effects of different organs (whole plant, shoot and root) aqueous extracts (AE) of Chenopodium album and Xanthium strumarium on the germination, emergence and seedling growth of Satureja hortensis. Germination and seedling growth experiments were performed in the laboratory, whereas emergence experiment was carried out under greenhouse conditions. The results showed that AE of different organs of C. album or X. strumarium had no significant effects on the germination percentage or rate, as well as on plumule dry weight of S. hortensis. However, the plumule or radicle length, the radicle or seedling dry weight and the emergence rate were significantly affected. In particular, X. strumarium root AE caused a stimulating effect (ranged from 22 to 33%) on the S. hortensis plumule and radicle length. On the contrary, all other X. strumarium or C. album AE reduced radicle length of S. hortensis. The X. strumarium root AE increased radicle dry weight up to 25%. However, C. album whole plant and shoot AE or X. strumarium whole plant AE reduced radicle and seedling dry weight of S. hortensis. The X. strumarium whole plant AE and C. album shoot AE reduced emergence rate of S. hortensis.

A phylogenetic analysis of Chenopodiaceae and Amaranthaceae was carried out using sequence variation of the chloroplast gene rbcL. Our sampling included 108 species of these two families along with 29 species of Caryophyllales serving as outgroups. Phylogeny inferences with maximum parsimony and maximum likelihood indicate that the two families form a well-supported monophyletic clade that is sister to Achatocarpaceae. Despite extensive sampling, we found that the relationship between Chenopodiaceae and Amaranthaceae remains unclear as a result of short and weakly supported basal branches. The clearly monophyletic Polycnemoideae (traditionally considered a subfamily of Chenopodiaceae) appear as sister to Amaranthaceae sensu stricto. Within Amaranthaceae, most major lineages inferred except Gomphrenoideae and Celosieae do not correspond to recognized subfamilies and tribes. Bosea and Charpentiera branch first in the Amaranthaceae. Within Chenopodiaceae, the genera of Betoideae occur in basal and largely unresolved positions. The remaining Chenopodiaceae are divided into three major clades of unclear relationship: Chenopodioideae (Atripliceae s.str., Chenopodieae I-III); Corispermoideae (Corispermeae); and Salicornioideae (Haplopeplideae, Salicornieae), Suaedoideae (Suaedeae, Bienertieae), and Salsoloideae (Camphorosmeae, Sclerolaeneae, Salsoleae I-II). The rbcL tree is discussed also with regard to historical classifications and morphological support for the major clades. The molecular results are used to elucidate the evolution of C 4 photosynthesis in the two families. C 4 photosynthesis has evolved independently at least three times in Amaranthaceae and at least 10 times in Chenopodiaceae. A survey of C 4 leaf anatomy revealed 17 different leaf types that in most cases mark an independent origin of C 4 photosynthesis. The application of a molecular clock indicates an age of C 4 photosynthesis of 11.5-7.9 Ma in Atriplex (Chenopodioideae) and 21.6-14.5 Ma in subfamily Salsoloideae.

X-ray microcomputed tomography (mCT) allows nondestructive visualisation of plant root systems within their soil environment and thus offers an alternative to the commonly used destructive methodologies for the examination of plant roots and their interaction with the surrounding soil. Various methods for the recovery of root system information from X-ray computed tomography (CT) image data have been presented in the literature. Detailed, ideally quantitative, evaluation is essential, in order to determine the accuracy and limitations of the proposed methods, and to allow potential users to make informed choices among them. This, however, is a complicated task. Three-dimensional ground truth data are expensive to produce and the complexity of X-ray CT data means that manually generated ground truth may not be definitive. Similarly, artificially generated data are not entirely representative of real samples. The aims of this work are to raise awareness of the evaluation problem and to propose experimental approaches that allow the performance of root extraction methods to be assessed, ultimately improving the techniques available. To illustrate the issues, tests are conducted using both artificially generated images and real data samples.

The "Thar Desert" region of Rajasthan in northwest India is one of the most inhospitable landscapes on earth. The desert has sparse vegetation and the ground surface is exposed to sun, atmosphere and associated physical forces. Ever increasing human and livestock population have put heavy demands for plant products, resulting in over exploitation of well adapted plants. Plants like species of Ceropegia, Caralluma, Calotropis, Leptadenia, Tylophora, Pueraria, Mucuna, Vitex and Sarcostemma are valuable sources of fuel, fodder, timber, medicine, biofertilizer (Endophytic rizobia) and vegetables for sustaining life in the desert. These plants are well adapted to the environment and contribute to the productivity, and keep the system photosynthetically active under all seasons. Attempt has also been made beside tissue culture, to isolate and purify the rhizobacteria associated with important native legumes of this region. These studies are important for sustainable agriculture practices.

1Extinction is a fundamental topic for population ecology and especially for conservation and metapopulation biology. Most empirical studies on extinction resurvey historically occupied sites and estimate extinction probability as the proportion of sites where a species is no longer detected. Possible non-detection of surviving populations is usually not accounted for, which may result in extinction probabilities that are overestimated.2As part of a large revisitation study in north-east Switzerland, 376 sites with historically known occurrences of a total of 11 plant species 80–100 years ago were visited by two independent observers. Based on typical population size, ramet size and plant architecture, we judged six species as easy to find and five species as hard to find. Using capture–recapture methods to separate non-detection from true extinction, we gauged the bias of extinction probability estimates that do not account for non-detection.3When non-detection was not accounted for, a single visit resulted in an average estimate of population extinction probability of 0.49 (range 0.27–0.67). However, the mean detection probability of a surviving population during a single visit had an estimated average of only 0.81 (range 0.57–1). Consequently, accounting for non-detection resulted in extinction probability estimates ranging between 0.09 and 0.61 (mean 0.36). Based on a single survey, our revisitation study would have overestimated the extinction rate on average by 11 percentage points (range 5–22%) or by 59% (range 0–250%) relative to the estimated true value.4A simple binomial argument enables the calculation of the minimum required number of visits to detect a surviving population with high probability (e.g. 95%). For the easy to find species, approximately two visits would be required to find most of the surviving populations, whereas up to four visits would be required for the hard to find species.5In revisitation studies, only repeated revisits allow the separation of extinction from simple non-detection. Unless corrected for possible non-detection, extinction probability may be strongly overestimated, and hence some control for non-detection is desirable at least in a subset of species/sites in revisitation studies. These issues are also relevant to the estimation of extinction in metapopulation studies and to the collection of quality data for habitat and distribution models.Extinction is a fundamental topic for population ecology and especially for conservation and metapopulation biology. Most empirical studies on extinction resurvey historically occupied sites and estimate extinction probability as the proportion of sites where a species is no longer detected. Possible non-detection of surviving populations is usually not accounted for, which may result in extinction probabilities that are overestimated.As part of a large revisitation study in north-east Switzerland, 376 sites with historically known occurrences of a total of 11 plant species 80–100 years ago were visited by two independent observers. Based on typical population size, ramet size and plant architecture, we judged six species as easy to find and five species as hard to find. Using capture–recapture methods to separate non-detection from true extinction, we gauged the bias of extinction probability estimates that do not account for non-detection.When non-detection was not accounted for, a single visit resulted in an average estimate of population extinction probability of 0.49 (range 0.27–0.67). However, the mean detection probability of a surviving population during a single visit had an estimated average of only 0.81 (range 0.57–1). Consequently, accounting for non-detection resulted in extinction probability estimates ranging between 0.09 and 0.61 (mean 0.36). Based on a single survey, our revisitation study would have overestimated the extinction rate on average by 11 percentage points (range 5–22%) or by 59% (range 0–250%) relative to the estimated true value.A simple binomial argument enables the calculation of the minimum required number of visits to detect a surviving population with high probability (e.g. 95%). For the easy to find species, approximately two visits would be required to find most of the surviving populations, whereas up to four visits would be required for the hard to find species.In revisitation studies, only repeated revisits allow the separation of extinction from simple non-detection. Unless corrected for possible non-detection, extinction probability may be strongly overestimated, and hence some control for non-detection is desirable at least in a subset of species/sites in revisitation studies. These issues are also relevant to the estimation of extinction in metapopulation studies and to the collection of quality data for habitat and distribution models.

Pungency in Capsicum fruits is due to the accumulation of the alkaloid capsaicin and its analogs. The biosynthesis of capsaicin is restricted to the genus Capsicum and results from the acylation of an aromatic moiety, vanillylamine, by a branched-chain fatty acid. Many of the enzymes involved in capsaicin biosynthesis are not well characterized and the regulation of the pathway is not fully understood. Based on the current pathway model, candidate genes were identified in public databases and the literature, and genetically mapped. A published EST co-localized with the Pun1 locus which is required for the presence of capsaicinoids. This gene, AT3, has been isolated and its nucleotide sequence has been determined in an array of genotypes within the genus. AT3 showed significant similarity to acyltransferases in the BAHD superfamily. The recessive allele at this locus contains a deletion spanning the promoter and first exon of the predicted coding region in every non-pungent accession tested. Transcript and protein expression of AT3 was tissue-specific and developmentally regulated. Virus-induced gene silencing of AT3 resulted in a decrease in the accumulation of capsaicinoids, a phenotype consistent with pun1. In conclusion, gene mapping, allele sequence data, expression profile and silencing analysis collectively indicate that the Pun1 locus in pepper encodes a putative acyltransferase, and the pun1 allele, used in pepper breeding for nearly 50 000 years, results from a large deletion at this locus.

Sequences from internal transcribed spacers (ITS) of nuclear ribosomal DNA were determined to examine phylogenetic relationships in the genus Acer. ITS 1 sequences in twenty-eight species of Acer and a species of Diptemnia in the family Aceraceae ranged from 220 to 242 bp and ITS 2 sequences from 215 to 251 bp. The size of the 5.8s coding region was 164 bp for all species examined in the family. Phylogenetic analysis of TTS sequences placed a very robust clade of section Palmata at the base of the tree. Three species of section Parvifora sensu de Jong (1994), A. spkatum, A. distylum and A. nipponicum, did not form a monophyletic clade. Acer spimfum was separated from the robust clade of A. disty/um and A. nipponicum. Molecular tree strongly supports the close relationship among section Plafanoidea, Glabra series Arguta, and section Macrantha. The close relationship between sections Penfaphyla and Trifoliata was also strongly suggested in ITS tree. Sections Rubra and Hyptiocarpa appeared to be closely allied with each other. The average rate of nucleotide substitution was estimated as (8.0f1.9)~10-" substitutions per site per year for ITS 1 and (9.0t-1.6)~10-~ for ITS 2.

The biochemical basis of heat/drought tolerance was investigated by comparing the response of antisense and sense transgenic soybean plants (containing the L-D 1pyrroline-5-carboxylate reductase gene) with non-transgenic wild-type plants. The plants were subjected to a simultaneous drought and heat stress of 2 days, whereafter they were rewatered at 251C. During this time the sense plants only showed mild symptoms of stress compared to the antisense plants which were severely stressed. Upon stress, nicotinamide adenine dinucleotide phosphate (NADP þ) levels decreased in antisense while it increased in sense plants. Recovery with respect to NADP þ levels was best in sense plants. Sense plants had the highest ability to accumulate proline

The Arabidopsis seed coat epidermis undergoes a complex process of differentiation that includes the biosynthesis and secretion of large quantities of pectinaceous mucilage, cytoplasmic rearrangement, and secondary cell wall biosynthesis. Mutations in MUM4 (MUCILAGE-MODIFIED4) lead to a decrease in seed coat mucilage and incomplete cytoplasmic rearrangement. We show that MUM4 encodes a putative NDP-l-rhamnose synthase, an enzyme required for the synthesis of the pectin rhamnogalacturonan I, the major component of Arabidopsis mucilage. This result suggests that the synthesis of monosaccharide substrates is a limiting factor in the biosynthesis of pectinaceous seed coat mucilage. In addition, the reduced cytoplasmic rearrangement observed in the absence of a key enzyme in pectin biosynthesis in mum4 mutants establishes a causal link between mucilage production and cellular morphogenesis. The cellular phenotype seen in mum4 mutants is similar to that of several transcription factors (AP2 [APETALA2], TTG1 [TRANSPARENT TESTA GLABRA1], TTG2 MYB61, and GL2 [GLABRA2]). Expression studies suggest that MUM4 is developmentally regulated in the seed coat by AP2, TTG1, and GL2, whereas TTG2 and MYB61 appear to be regulating mucilage production through alternate pathway(s). Our results provide a framework for the regulation of mucilage production and secretory cell differentiation.

With the establishment of advanced technology facilities for high throughput plant phenotyping, the problem of estimating plant biomass of individual plants from their two dimensional images is becoming increasingly important. The approach predominantly cited in literature is to estimate the biomass of a plant as a linear function of the projected shoot area of plants in the images. However, the estimation error from this model, which is solely a function of projected shoot area, is large, prohibiting accurate estimation of the biomass of plants, particularly for the salt-stressed plants. In this paper, we propose a method based on plant specific weight for improving the accuracy of the linear model and reducing the estimation bias (the difference between actual shoot dry weight and the value of the shoot dry weight estimated with a predictive model). For the proposed method in this study, we modeled the plant shoot dry weight as a function of plant area and plant age. The data used for developing our model and comparing the results with the linear model were collected from a completely randomized block design experiment. A total of 320 plants from two bread wheat varieties were grown in a supported hydroponics system in a greenhouse. The plants were exposed to two levels of hydroponic salt treatments (NaCl at 0 and 100 mM) for 6 weeks. Five harvests were carried out. Each time 64 randomly selected plants were imaged and then harvested to measure the shoot fresh weight and shoot dry weight. The results of statistical analysis showed that with our proposed method, most of the observed variance can be explained, and moreover only a small difference between actual and estimated shoot dry weight was obtained. The low estimation bias indicates that our proposed method can be used to estimate biomass of individual plants regardless of what variety the plant is and what salt treatment has been applied. We validated this model on an independent set of barley data. The technique presented in this paper may extend to other plants and types of stresses.

Ca 2+ -calmodulin (Ca 2+ -CaM) is a critical molecule that mediates cellular functions by interacting with various metabolic and signaling pathways. However, the protein expression patterns and accompanying serial cytological responses in Ca 2+ -CaM signaling deficiency remain enigmatic. Here, we provide a global analysis of the cytological responses and significant alterations in protein expression profiles after trifluoperazine treatment in Picea meyeri, which abrogates Ca 2+ -CaM signaling. Ninety-three differentially displayed proteins were identified by comparative proteomics at different development stages and were assigned to different functional categories closely related to tip growth machinery. The inhibition of Ca 2+ -CaM signaling rapidly induced an increase in extracellular Ca 2+ influx, resulting in dramatically increased cytosolic Ca 2+ concentrations and ultrastructural abnormalities in organelles as the primary responses. Secondary and tertiary alterations included actin filament depolymerization, disrupted patterns of endocytosis and exocytosis, and cell wall remodeling, ultimately resulting in perturbed pollen tube extension. In parallel with these cytological events, time-course experiments revealed that most differentially expressed proteins showed time-dependent quantitative changes (i.e. some signaling proteins and proteins involved in organelle functions and energy production changed first, followed by alterations in proteins related to cytoskeletal organization, secretory pathways, and polysaccharide synthesis). Taken together, Ca 2+ -CaM dysfunction induced serial cytological responses and temporal changes in protein expression profiles, indicating the pivotal role of Ca 2+ -CaM in the regulation of tip growth machinery.

Genetic analysis of the transition from embryogenesis to germination has shown that these processes are under strict sequential, mutually exclusive, control. Understanding the regulation of this phase transition should provide important approaches to new technologies that can be used to improve seed quality traits in crop plants.

The pattern of leghaemoglobin (Lb) gene expression within the indeterminate nitrogen-fixing root nodule of Medicago species such as alfalfa has been examined by means of 'in-sifu' hybridization. Hybridization of alfalfa nodule sections with radiolabelled Lb RNA probes clearly shows that Lb gene expression is triggered in a single cell layer just prior to the start of the nitrogen fixation zone. This cell layer is part of a unique region (interzone 11-111) in which invaded cells are rich in amyloplasts. Lb transcripts can only be detected in cells which have been invaded by the microsymbiont Rhizobium. The conclusion that Lb gene activation precedes the start of nitrogen fixation is further supported by the observation that Lb transcripts are already present in immature non-nitrogen-fixing nodules of alfalfa. The addition of 5 mM KN03 to the growth medium of nodulated M. truncatula (a diploid autogamous species of Medicago) results in a significant drop in both nitrogen-fixing activity and nodular Lb mRNA levels. Short periods of exposure to nitrate (24 h) lead to the disappearance of Lb transcripts from the proximal region of the hybridizing zone, whilst longer exposures (72 h) lead to a marked decrease in the intensity of the hybridization signal within the amyloplast-rich interzonal region.

Of the available medications for treating alcohol-related problems, none are universally effective, and all have side effects that may limit their use. Extracts of kudzu containing a variety of isoflavones have been shown to reduce alcohol drinking in rats and hamsters.

Various sites in the valley of the Sant Cugat stream in Cerdanyola del Vallès (Catalonia) were subject to systematic archaeobotanical sampling to obtain an overview of the crops and agriculture of the area during the Iron Age and late antiquity. In all cases, the most numerous taxa were crop plants. Among these, cereals were clearly predominant at all sites investigated, especially Hordeum vulgare var. vulgare (hulled barley) and Triticum aestivum/ durum (bread or macaroni wheat), both in numbers and frequency. Other cereals, such as Triticum dicoccum (emmer) or Setaria italica (foxtail bristle-grass), were regularly present in considerably lower numbers but in fairly high frequencies. Pulses were much less numerous, although their presence increases in terms of frequency. Among them, clearly the best represented was Lens culinaris (lentil). The results show that the agriculture in the period considered was principally based on winter cereals, with a gradual substitution of hulled barley by bread/hard wheat, accompanied by other cereals of minor importance, led by Triticum dicoccum (emmer), and pulses. The appearance of Vitis (grapevine) in the Iberian period is one of the important characteristics of agriculture in the Iberian world.

Background: Lepidium meyenii (maca) is a plant that grows exclusively in the Peruvian Central Andes, where ultraviolet radiation (UVR) is predominant. Objective: Determine if two extracts of maca can provide dermal protection against UVR. Methods: We have administered two maca extracts (0.13 mg/ml), one obtained after boiling and the other without boiling, on the dorsal surface of male Holtzman rats exposed to UVC radiation once a week during 3 consecutive weeks. A dose-response effect of an aqueous extract of maca after a boiling process under exposure of rats to UVA, UVB, or UVC was also studied. A commercial sunscreen was used as a positive control. Results: UVR caused significant increase in skin epidermal thickness. The epidermal height in animals treated with maca was similar to those who did not receive UVR. The aqueous extract of maca after a boiling process had better effect than maca extract without a boiling process. A dose-response effect was observed with increasing doses of aqueous extract of maca after a boiling process. Maca extract had benzyl glucosinolates and polyphenols. Conclusions: Maca extracts protect the skin of rats against UV irradiations and can be suggested as an alternative means of solar protection.

Morphometric data have long suggested the existence of three species of Sicyos in Australia and New Zealand. Molecular data now corroborate this and place the three species in the context of the remaining 72 species of Sicyos, most of them in the New World. We here describe and illustrate Sicyos undara I.Telford & P.Sebastian from northern Queensland and S. mawhai I.Telford & P.Sebastian from New Zealand, and emend the circumscription of S. australis to account for the removal of these two extraneous elements. We also provide a key to the three species, map their ranges, and note their habitat and conservation status.

Soilless plant growth systems are widely used as a means to save irrigation water and to reduce groundwater contamination. While nutrient concentrations in the growth medium are depleted due to uptake by the plants, salinity and toxic substances accumulate due to transpiration. A theoretical model is suggested, to simulate nutrient uptake by plants grown in soilless cultures with recycled solutions. The model accounts for salinity accumulation with time and plant growth, and its effects on uptake of the different nutrients by means of interaction with Na and Cl ions. The sink term occurs due to uptake by a growing root system. Influx as a function of the ion concentration is according to Michaelis-Menten active mechanisms for K + , NO 3 − -N, NH 4 + -N, PO 4 -P, Ca 2+ , Mg 2+ and SO 4 2− , whose influx parameters are affected by Na and Cl − , but not with time (age). Sodium influx is passive above a critical concentration. Sum of cations-anions concentrations is balanced by Cl − to maintain electro-neutrality of the growth solution. Salinity (by means of Na concentration) suppresses root and leaf growth, which further effect uptake and transpiration. The model accounts for instantaneous transpiration losses, during daytime only and its effect on uptake of nutrients and plant development due to salt accumulation. The model was tested against NO 3 − and K + uptake by plants associated with cumulative transpiration and with different NaCl salinity levels. Deviations from observed K + uptake should be attributed to the salinity tolerance of the plants. In a study with data obtained from published literature, the model indicated that nutrient depletion and salinity buildup might be completely different with fully grown-up plants (that do not grow) and plants that grow with time. Depletion of different nutrients are according to their initial concentration and plant uptake rate, but also affected by their interactions with Na and Cl ions.

New insights into the phenomenon of systemic acquired resistance have been gained in recent years, by the use of techniques in molecular genetics and biology that have replaced the largely descriptive approach of earlier work. The isolation of mutants in the signal transduction pathway from induction to expression of resistance as well as the use of transgenic plants over-expressing or suppressing the expression of putative candidate genes involved in systemic acquired resistance and its signalling have identified several steps in the establishment of plant resistance. In this review the latest developments implicating salicylic acid as a signal molecule in systemic resistance are discussed and contrasted with new signalling pathways which, seemingly, are based on alternative mechanisms.

All organisms have evolved strategies to regulate ion and pH homeostasis in response to developmental and environmental cues. One strategy is mediated by monovalent cation-proton antiporters (CPA) that are classified in two superfamilies. Many CPA1 genes from bacteria, fungi, metazoa, and plants have been functionally characterized; though roles of plant CPA2 genes encoding K(+)-efflux antiporter (KEA) and cation/H(+) exchanger (CHX) families are largely unknown. Phylogenetic analysis showed that three clades of the CPA1 Na(+)-H(+) exchanger (NHX) family have been conserved from single-celled algae to Arabidopsis. These are (i) plasma membrane-bound SOS1/AtNHX7 that share ancestry with prokaryote NhaP, (ii) endosomal AtNHX5/6 that is part of the eukaryote Intracellular-NHE clade, and (iii) a vacuolar NHX clade (AtNHX1-4) specific to plants. Early diversification of KEA genes possibly from an ancestral cyanobacterium gene is suggested by three types seen in all plants. Intriguingly, ...

Navas-Cortés, J. A., Landa, B. B., Méndez-Rodríguez, M. A., and Jiménez-Díaz, R. M. 2007. Quantitative modeling of the effects of temperature and inoculum density of Fusarium oxysporum f. sp. ciceris races 0 and 5 on development of Fusarium wilt in chickpea cultivars. Phytopathology 97:564-573.

Although numerous physiological studies have addressed the interactions between brassinosteroids and auxins, little is known about the underlying molecular mechanisms. Using an Affymetrix GeneChip representing approximately 8,300 Arabidopsis genes, we studied comprehensive transcript profiles over 24 h in response to indole-3-acetic acid (IAA) and brassinolide (BL). We identified 409 genes as BL inducible, 276 genes as IAA inducible, and 637 genes in total. These two hormones regulated only 48 genes in common, suggesting that most of the actions of each hormone are mediated by gene expression that is unique to each. IAA-up-regulated genes were enriched in genes regulated in common. They were induced quickly by IAA and more slowly by BL, suggesting divergent physiological roles. Many were early auxin-inducible genes and their homologs, namely SAUR, GH3, and IAA. The comprehensive comparison also identified IAA-and BL-specific genes, which should help to elucidate the specific actions of each hormone. The identified genes were classified using hierarchical clustering based on the similarity of their responses to the two hormones. Gene classification also allowed us to analyze the frequency of cis-elements. The TGTCTC element, a core element of the previously reported auxin response element, was not enriched in genes specifically regulated by IAA but was enriched in the 59-flanking region of genes up-regulated by both IAA and BL. Such gene classification should be useful for predicting the functions of unknown genes, to understand the roles of these two hormones, and the promoter analysis should provide insight into the interaction of transcriptional regulation by the two hormones. fax 81-45-503-9492.

... Truffle tyrosinase: Properties and activity Michele Miranda&amp;amp;#x27;, Antonella Bonfiglia, Osvaldo Zarivia, Anna Maria Ragnellia, Giovanni Pacionib and ... BC Malmstrom, LE Andreasson and B. Reinhammar, Copper-containing oxidases and superoxide dismutase, in: PD Boyer (Ed.), The ...

The present study was carried out to investigate the effect of plant growth promoting thermotolerant Pseudomonas putida strain AKMP7 on the growth of wheat plants to heat stress. The results indicated the superior performance by P. putida strain AKMP7 in improving survival and ...

The synergetic effect of organic (cow manure) and mineral fertilization on the development arbuscular mycorrhizal (AM) fungi was demonstateded. The length of AM mycelium and sporulation were used as sensitive markers of the physiological state of soil AM fungal population. In manured treatments, both parameters increased in proportion with increasing mineral fertilization. In unmanured soil, the opposite

Botrytis cinerea isolates from flowers and berries of Vitis vinifera 'Thompson seedless' (grapevine) were characterized in terms of two transposable elements (TEs) Boty and Flipper, random amplified polymorphic DNA (RAPD), infection levels, and resistance to iprodione. The isolates were collected from grapevines under fungicide programs of variable numbers of iprodione applications, and replicated in three Chilean Central Valley locations. Recovery was repeated from clusters collected at four phenological stages. Highest infection levels were found at bloom. Fungicide programs including one iprodione application or a combination of other fungicides were most effective for reducing gray mold symptoms. A total of 457 isolates collected from fungicide programs including only one iprodione application, and the control program, were tested for the presence of TEs. In all locations and during all phenological stages, transposa isolates (containing both TEs) were most common, followed by Boty. Vacuma isolates (containing neither TE) were identified at very low levels in two locations and only in the control treatment, and isolates with only Flipper were not detected at any time or location. Vacuma and Boty isolates were all sensitive to iprodione, while transposa isolates showed a wide range of resistance. Based on response to iprodione, the presence of TEs, and presence of vegetative-incompatibility alleles (Bc-hch), the isolates studied belong to B. cinerea Group II, a phylogenetic species within B. cinerea. Hierarchical analysis of molecular variance and genetic diversity analyses of the RAPD genotypes showed a genetic differentiation linked to location, but it was not related to geographic distance. Moreover, a genetic differentiation related to the phenological stage of grapes was also detected.

We combined single pollen typing with laser-mediated manipulation. After drilling a hole in the wall of a pollen grain from a dioecious plant (Silene latifolia) with a UVlaser microbeam, the single pollen grain was recovered directly in the cap of a PCR tube, using a non-contact method called laser pressure catapulting. The entire genome of the single pollen grain was then ampli®ed with improved primer-extension-preampli®cation PCR (I-PEP PCR). Nested PCR with sequence tagged site (STS)-speci®c primers was used to analyze several loci in the haploid genome. The single copy gene MROS1 was detected in most of the single pollen grains analyzed. Bgl10, which is localized on the Y chromosome, was detected in approximately half of the pollen grains. MROS3 is reported to be localized on the X chromosome. Using inverse PCR, we isolated two genomic clones of MROS3: MROS3A and MROS3B. The single pollen analysis using nested PCR showed that MROS3A and MROS3B are derived from different loci that are not located on the X chromosome. Single pollen typing not only reveals sex chromosome-linkage within the haploid genome, but can also discriminate between alleles and different loci. This method should also be useful for measuring recombination frequencies without genetic crossover analysis.

Objetivou-se neste trabalho elaborar e validar uma escala diagramática para a ferrugem alaranjada da cana-de-açúcar e comparar a sua eficiência em avaliar a doença com a escala da ferrugem marrom. Para elaboração da escala foram coletadas 120 folhas de uma cultivar suscetível à doença, e a maior e menor severidades encontradas representaram os extremos da escala. Os níveis intermediários foram calculados respeitando a lei de Weber-Fechner. A escala foi proposta com nove níveis de severidade: 0,06; 0,14; 0,36; 0,89; 2,17; 5,18; 11,87; 24,92 e 45,00%. Oito avaliadores realizaram a validação estimando a severidade de 120 folhas em três avaliações: sem escala, com a escala da ferrugem marrom e com a escala da ferrugem alaranjada. A escala elaborada foi mais eficiente para avaliar a doença, proporcionando um coeficiente de determinação (R 2 ) médio de 0,91 e ausência de erros constantes e sistemáticos. Com a escala da ferrugem marrom, o R 2 médio foi de 0,84, e três avaliadores cometeram desvios constantes. Com a escala elaborada, aproximadamente 92% das estimativas estiveram na faixa de variação de 5% do valor real, enquanto que nas avaliações sem escala e com a escala da ferrugem marrom, aproximadamente 78% e 84% das estimativas, estiveram nessa faixa, respectivamente. Palavras-chave: Puccinia kuehnii, Saccharum spp., patometria, severidade.

ABSTRACT Guava (Psidium guajava) fruit is vulnerable to postharvest diseases, such as anthracnose. In the present study, molecular characterisation and pathogenicity of Colletotrichum associated with antharcnose disease of guava fruit were conducted. From anthracnose lesion of guava, 20 isolates were successfully recovered. Based on colony colours, conidia, appressoria and presence or absence of setae, and ITS regions and ß-tubulin gene sequences, the isolates were identified as Colletotrichum gloeosporioides. Phylogenetic analysis based on combined data-sets using neighbour-joining method showed that C. gloeosporioides isolates did not group with C. gloeosporioides epitype strain, and thus the isolates were referred to as C. gloeosporioides species complex or C. gloeosporioides sensu lato. Pathogenicity tests using wounded treatment showed that C. gloeosporioides isolates from guava were pathogenic causing anthracnose on the fruits. The present study showed that C. gloeosporioides sensu lato is the most common species causing antharcnose disease of guava fruit.

Language is the expression of mind and a channel for communication. Language is the baby of intelligence. Do plants have intelligence? If so, what is their language of expression? The biological clock of the plant to comprehend the surrounding climate is no way inferior to the weather forecast by human intelligence.

The rhizosphere is a densely populated area in which plant roots must compete with invading root systems of neighboring plants for space, water, and mineral nutrients, and with other soil-borne organisms, including bacteria and fungi. Root-root and root-microbe communications are continuous occurrences in this biologically active soil zone. How do roots manage to simultaneously communicate with neighboring plants, and with symbiotic and pathogenic organisms within this crowded rhizosphere? Increasing evidence suggests that root exudates might initiate and manipulate biological and physical interactions between roots and soil organisms, and thus play an active role in root-root and root-microbe communication. Glossary Allelopathy: Chemical inhibition of one species by another. Allelochemicals: Small molecular weight phyto-inhibitory compounds produced by a plant to ward-off another plant. Chemotaxis: Phenomenon by which a biotic adherence takes place by virtue of the production of a chemical signal. Edaphic factors: Involve both biological and abiotic climatic conditions required to regulate a specific niche. Root exudates: The chemicals secreted into the soil by roots.

Laser-Induced Breakdown Spectroscopy (LIBS) is a sensitive optical technique capable of fast multi-elemental analysis of solid, gaseous and liquid samples. Since the late 1980s LIBS became visible in the analytical atomic spectroscopy scene; its applications having been developed continuously since then. In this paper, the use of LIBS for trace element determination in different matrices is reviewed. The main emphasis is on spatially resolved analysis of microbiological, plant and animal samples.

Respiration is vital; it is the essence of life. Respiration is the mechanism by which energy obtained during the photosynthesis process is transformed into biochemical energy, in the form of ATP. This transformation of energy keeps all cells in all organisms alive. While energy conversion is the main function of respiration in animals, respiration has several other functions in plants. Among them, interactions with photosynthesis such as photorespiration and the production of carbon skeletons for the many compounds synthesized in plants (e.g., pigments, proteins and secondary metabolites). Therefore, it comes as no surprise that such a key role of respiration in plants promoted intense effort to investigate its regulation. Nevertheless, the interactions with other simultaneous processes make its measurement in plants very challenging. In animals, respiration can be simply measured as CO2 or O2 exchange with the atmosphere since there are no other processes performing similar gas exchange. In contrast, in plants, respiration produces CO2 and consumes O2 simultaneously with photorespiration.