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Orchids are among the most cultivated flowers in the world. Plants of Dendrobium thyrsiflorum (DT) and Cattleya wittigiana (CW), cultivated at the Botanic Garden of Bauru in São Paulo, Brazil, presented black rot symptoms. The causal organism was identified as P. palmivora on DT and P. nicotianae on CW orchids based on its morphological and molecular characterization. Inoculation caused disease symptoms and Koch's postulates were fulfilled by re-isolation of the pathogen. [ABSTRACT FROM AUTHOR]

The correction notice in Plant Biosystems addresses the interchange of Figures 1 and 2 in the article "Storage of Brazilian Cattleya seeds from diverse biomes: lipid composition and effects on germination." The figures have been correctly placed in the original article, showing the germination and germination speed index of different Cattleya species under various storage conditions. The study explores the impact of lipid composition on seed germination, providing valuable insights for plant biology research. [Extracted from the article]

Orchids are notable for the variety of rewards produced for their pollinators. Nevertheless, many species are rewardless and pollinated by food‐deceptive strategies. This is the case for Cattleya, a Neotropical genus of more than 100 species supposedly pollinated by food‐deception.Here, I studied a member of the clade Sophronitis (Cattleya cernua) in forest areas of southeastern Brazil. The study included analyses of floral morphology, light microscopy of secretory tissues, histochemistry of flower resources, and measurements of nectar volume and concentration. Data on pollinators and mechanisms of pollination were collected in the field by means of film records, while breeding systems were studied using experimental treatments applied to cultivated specimens.The flower traits of Cattleya cernua show strong adaptation to avian pollination. Flowers produce 1–7 μl of a moderately concentrated nectar (17–50%). A secretory tissue at the distal portion of the cuniculus is responsible for nectar secretion. Secreted nectar is stored in the nectar chamber. Pollinaria deposition on the apex of bird beaks allows both short‐ and long‐billed birds to pollinate the flowers. Plants from the studied population were fully self‐compatible but pollinator‐dependent. Pollinator frequency was higher than in food‐deceptive Cattleya.As far as is known, this is the first record of nectar production in Cattleya. The discovery of a reward‐producing species (C. cernua) within a genus entirely pollinated by food‐deception strategies (Cattleya) provides clues and new insights into understanding the diversification of Laeliinae across the Neotropics. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Epidendrum, one of the three largest genera of Orchidaceae, exhibits significant horticultural and ornamental value and serves as an important research model in conservation, ecology, and evolutionary biology. Given the ambiguous identification of germplasm and complex evolutionary relationships within the genus, the complete plastome of this genus (including five species) were firstly sequenced and assembled to explore their characterizations. The plastomes exhibited a typical quadripartite structure. The lengths of the plastomes ranged from 147,902 bp to 150,986 bp, with a GC content of 37.16% to 37.33%. Gene annotation revealed the presence of 78–82 protein-coding genes, 38 tRNAs, and 8 rRNAs. A total of 25–38 long repeats and 130–149 SSRs were detected. Analysis of relative synonymous codon usage (RSCU) indicated that leucine (Leu) was the most and cysteine (Cys) was the least. The consistent and robust phylogenetic relationships of Epidendrum and its closely related taxa were established using a total of 43 plastid genomes from the tribe Epidendreae. The genus Epidendrum was supported as a monophyletic group and as a sister to Cattleya. Meanwhile, four mutational hotspots (trnCGCA–petN, trnDGUC–trnYGUA, trnSGCU–trnGUCC, and rpl32–trnLUAG) were identified for further phylogenetic studies. Our analysis demonstrates the promising utility of plastomes in inferring the phylogenetic relationships of Epidendrum. [ABSTRACT FROM AUTHOR]

Leaves of a Cattleya × hybrid registered in Taichung, Taiwan developed dark-brown necrotic lesions with a yellow halo. Two isolates (CaRh1 and CaRh2) were collected and identified as Rhizoctonia solani AG-4 HG-I based on morphology and molecular characteristics. Leaves of this Cattleya and other orchids (Dendrobium sp., Oncidium sp. and Phalaenopsis sp.) that were wound-inoculated with the two isolates developed dark-brown, slightly sunken necrotic lesions. This is the first report of R. solani AG-4 HG-I causing symptoms on leaves of Cattleya × hybrid in Taiwan. [ABSTRACT FROM AUTHOR]

The technology for reproducing orchids in vitro has had to evolve due to the demand for these plants and the high cost of the biotechnology used due to the agar, the gelling agent. Consequently, research has tended to search for natural substitutes for agar. Our work describes the use of pectin and mucilage hydrocolloids extracted from the local waste matter of two species of Opuntia (O. ficus-indica and O. robusta) to study as a gelling agent in vitro culture media for Cattleya sp. These hydrocolloids were obtained by alkaline hydrolysis. Subsequently, these were used in proportions of 0.8%, 0.6%, 0.4%, and 0.2% in combination with agar to study the gelation time, texture profile analysis (TPA), seed germination under light and dark conditions, and a phenological study, including orchid analyses of leaves and roots, root and leaf length, seedling height, and width of the best-designed treatment were studied. Our results demonstrate that the treatment composed of 0.4% O. ficus-indica pectin and 0.4% agar improves the germination time, plant growth, and the number of leaves and roots, resulting in a biostimulant formula for optimal in vitro growth of Cattleya sp. [ABSTRACT FROM AUTHOR]

Orchid flowers have a unique structure that consists of three sepals and three petals, with one of the petals forming the labellum (lip) that can be differentiated into the hypochile and epichile. In orchids, the emission of floral scent is specific and spatially complex. Little is understood about the molecular and biochemical mechanisms of the differing scent emissions between the parts of orchid flowers. Here, we investigated this in the Cattleya hybrid KOVA, and our study showed that monoterpenes, including linalool and geraniol, are the main components responsible for the KOVA floral scent. The KOVA flower was scentless to the human nose before it reached full bloom, potentially because the 1-deoxy-d-xylulose 5-phosphate synthases (RcDXSs) and 4-hydroxy-3-methylbut-2-enyl diphosphate synthases (RcHDSs) that biosynthesize monoterpenes were highly expressed in flowers only when it reached full flowering. Additionally, the spatial expression profile of the monoterpene synthases (RcMTPSs), which were highly expressed in the basal region of the lip (hypochile), contributed to the highest monoterpene emissions from this part of the flower. This might have caused the hypochile to be more fragrant than the other parts of the flower. These findings enrich our understanding of the difference in scents between different flower parts in plants and provide information to breed novel orchid cultivars with special floral scents. [ABSTRACT FROM AUTHOR]

The Cattleya (Orchidaceae–Laeliinae subtribe) intergeneric hybrids, such as Brassolaeliocattleya (Blc.), have great ornamental value, due to their compact-size, with large and high color diversity of flowers. Artificial induction of polyploidy brings agronomic, ornamental and genetic benefits to plants. Polyploidization efficiency depends on factors, such as the type of antimitotic, polyploidization method, concentrations, exposure times and type of explant. This study aimed to develop a protocol to polyploidize Blc. orchids, by testing two types of explants (seeds and protocorms), concentrations and exposure times to colchicine. The effects of colchicine on the in vitro development of explants were also investigated. The responses of explants to colchicine depended on the concentrations, exposure time and the interaction of these factors. Flow cytometric analysis evidenced high endopolyploidy and allowed the separation of polyploidized (4C, 8C and 16C peaks) from non-polyploidized (only 2C and 4C peaks) plants. The highest percentage of polyploid plants was regenerated from protocorms (16.4%) treated with colchicine instead of seeds (3.2%). Protocorms treated with colchicine at 500–750 μM for 18 h resulted in the best percentage of polyploidization. Additionally, in vitro natural polyploidization using protocorms was reported (11.5%). Cytological analyses allowed an estimation of the number of chromosomes of the parents (≡70), polyploidized (≡140) and non-polyploidized progeny (≡70). [ABSTRACT FROM AUTHOR]

In vitro propagation is an important technique to produce orchids since it allows the multiplication and marketing of specimens with outstanding characteristics that have more commercial acceptance. By following this practice, natural populations are protected and the use of orchids is carried out in a sustainable manner. The objective was to evaluate the effect of three concentrations of 6-benziladenine (BA) on the growth and development of protocorms in cattleya (Brassolaeliocattleya) seedlings in vitro. The protocorms from the seeds were subcultured to a new medium with the same characteristics but adding BA in three different treatments: 1.0 mg·L-1, 1.5 mg·L-1 and 2.0 mg·L-1. The in vitro growth and development of protocorms presented a better result by adding BA in 1.5 mg L-1 doses, where plant height, leaf length, leaf number and root length were promoted, obtaining large and vigorous seedlings for transplanting and acclimatization. [ABSTRACT FROM AUTHOR]

Introduction: Cattleya crispa is an ornamental epiphytic orchid with geographic distribution restricted to the Brazilian Atlantic Forest. Due to predatory extractivism and human-induced habitat loss, this species appears on the Red List of Brazilian Flora. Objective: To characterize morpho-anatomical aspects regarding germination and post-seminal development from C. crispa seeds; as well as studying the effect of cryopreservation on these seeds. Methods: We used light microscopy and electron microscopy to describe the microstructure of a 100 ripe seeds. We evaluated seed viability, seed germination, survival rate and protocorm weight in cryopreserved and noncryopreserved material, with four replicas per treatment using 20 mg of plant material. Results: The seeds are fusiform, whitish yellow with a length from 700 to 900 µm and a water content of 5 %. Germination began seven days after sowing, the formation of the globular protocorm at 30 days and the formation of the seedling occurred 150 days. The persistent seed coat can compress the protocorm and cause it to collapse. The cryopreserved seeds presented 87.15 % viability, 78.32 % germination, 8.48 % survival and protocorms with 104.27 mg five months after sowing. Data wasn't different to non-cryopreserved seeds. Conclusions: The cryocapability of the seeds shows that cryopreservation can be used for long-term conservation. The results of this work contribute to the overall biology of C. crispa and to the propagation and storage of genetic material for conservation purposes. [ABSTRACT FROM AUTHOR]

• TDZ was effective for inducing PLBs from leaf explants of C. tigrina. • GA 3 significantly increases shoot regeneration from PLBs. • Cattleya tigrina leaves are endopolyploid, with 2C, 4C and 8C DNA content cytotypes. • 26.5% of the plantlets regenerated from PLB presented duplicated ploidy levels. • The ploidy level of the regenerants changes stomatal density and morphology. The induction and subsequent regeneration of protocorm-like bodies (PLB) is the most common morphogenetic pathway for orchid micropropagation. The regeneration of plants from PLB can be a bottleneck for some species due to asynchronicity. Genetic fidelity is another issue, and the cytogenetic stability of regenerated plantlets deserves special attention due to the common occurrence of endopolyploidy in orchids. In the present work, we defined optimal conditions for PLB induction and plant regeneration for Cattleya tigrina , a threatened orchid from the Brazilian Atlantic Rain Forest. We estimated the optimum thidiazuron (TDZ) concentration for PLB induction from leaf explants, while also comparing whole leaves vs thin cell layer (TCL) as explants. For plantlet regeneration from PLB clusters, we investigated the effects of different concentrations of GA 3 and sucrose, as well as the dehydration of PLBs and the use of temporary vs continuous immersion systems. Furthermore, the cytogenetic stability of regenerated plantlets was analyzed using flow cytometry, and the differences in stomatal morphology were studied. Exogenous TDZ (25 µM) was the most effective concentration for PLB induction, with 17.5% induction rate. Leaf basal regions, either in whole leaves or in TCL, were the most responsive for PLB induction. The dehydration of PLBs for 120 min increased the fresh weight increment (FWI) in plantlet regeneration, but at the expense of decreased shoot number and increased mortality. Temporary-immersion bioreactors were found to be the most suitable system for PLB multiplication compared to continuous immersion system. Shoot development was challenging due to previously acquired habituation to TDZ. Sucrose and GA 3 showed an interactive effect on shoot growth. GA 3 improved shoot formation, and maximum shoot production was estimated to occur at 10.3 and 9.7 µM GA 3 on media containing 1.5% and 2% sucrose, respectively, resulting in larger number of developed plantlets (∼220) per culture flask. The flow cytometry analysis showed that 26.5% of plants regenerated from PLBs had doubled ploidy levels. The ploidy alterations were reflected in changes on leaf epidermis, such as increased stomatal density and number. [ABSTRACT FROM AUTHOR]

• Chlorine pretreatments at 1% and 0.5% have a greater influence on the viability of C. gaskelliana and C. warscewiczii seeds. • Tetrazolium concentration and exposure time play an important role in the identification of viable seeds in C. gaskelliana and C. warscewiczii. • The culture media supplemented with coconut water and pineapple juice were the most suitable for the germination and formation of C. gaskelliana and C. warscewiczii seedlings. • The use of organic components in the culture media favors the germination of the seeds, stimulates the growth and development of C. gaskelliana and C. warscewiczii. Worldwide, orchid species are threatened mainly due to human action. For this reason, it is important search for inexpensive in vitro culture media that will help their rapid germination, propagation and conservation. Therefore, this research evaluated the viability, germination and in vitro development of Cattleya gaskelliana and Cattleya warscewiczii using different culture media. Capsules of the orchids were collected, seeds were submitted to different pretreatments (Chlorine 0.5%, Chlorine 1%, distilled water and Sucrose) and seed viability were tested with two concentrations of tetrazolium (0.25% and 0.5%) and two exposure times (24 h and 48 h). Afterwards, the seeds were grown on the following culture media: Murashige and Skoog (MS) basal medium, MS plus 0.5 mg L −1 of indoleacetic acid (MS+IAA), MS plus 0.5 mg L −1 of gibberellic acid (MS+GA3), MS supplemented with coconut water (MS+C), MS supplemented with pineapple juice (MS+ P) and the commercial medium Orchid Seed Sowing Medium (OSM). Viability for Cattleya gaskelliana was 90.6% in 0.5% tetrazolium, whereas for Cattleya warscewiczii was 90% in 0.25% concentration at 48 h exposure. The most efficient media regarding seedling development of C. gaskelliana and C. warscewiczii during 18 weeks of cultivation were MS+C and MS+ P with significant differences (P ≤ 0.05). The use of organic components in the culture media, favors the seeds germination, stimulates the growth and development of C. gaskelliana and C. warscewiczii, contributing in this way, in the decrease of costs generated by plant growth regulators. [ABSTRACT FROM AUTHOR]

Cattleya tigrina A. Rich has been suffering heavy losses in its natural habitat and it is now included in the list of plants that are vulnerable to extinction. The development of in vitro propagation and conservation methodologies, as well as acclimatization, are considered important for species at the risk of extinction, as they promote the multiplication and conservation of the species, hence avoiding the loss of their genetic variability. The present study established the protocol of micropropagation and the in vitro conservation of C. tigrina. For the in vitro propagation, the study tested two volumes of the MS medium and two medium consistencies (stationary liquid and semi-solid). For acclimatization, the substrate mixtures containing pine bark, charcoal, vermiculite, and coconut coir were analyzed. For the in vitro conservation, different concentrations of the salts were tested in the MS medium, together with the osmotic regulators (sucrose, mannitol, and sorbitol), and at two temperatures (18 and 25 °C). The results obtained inferred that the semi-solid medium was superior to the stationary liquid medium in the variables of survival and the presence of roots, while the liquid medium was superior to the semi-solid medium in the number of shoots. For acclimatization, pine bark was the substrate where the plants developed an improved height, with sprouting, and rooting. The conservation was satisfactory and the plants remained viable for a period of 730 days, with the MS medium with 25% of the salts, and at temperatures of 18 °C or 25 °C. The plants were propagated in the stationary liquid MS medium (10 mL) and the semi-solid medium (25 mL), while they were acclimatized in pine bark and preserved in the MS medium with 25% of the salts (18 °C or 25 °C). [ABSTRACT FROM AUTHOR]

Studies involving morphological and anatomical changes resulting from seed storage are rare, but relevant to ensure information related to the quality of seeds and seedlings originated from these seeds. The objectives of this work as to carry out the anatomical and histochemical characterization of seeds from the Cattleya intermedia orchid, verifying the occurrence of possible alterations coming from different temperatures and storage periods. The treatments consisted of temperatures of: 25 (± 2 °C) (room), -20 °C (freezer), -80 °C (ultra freezer) and - 196 °C (cryopreservation); and storage periods: two, four and six months. For the anatomical and histochemical analyses, scanning electron microscopy and light microscopy were performed. The following stains were employed: toluidine blue (TBO), Coomassie brilliant blue (CBB), Sudan IV and periodic acid-Schiff (PAS). The dehydration observed in the seeds was considered the main damage resulting from storage. Changes in the internal structures of the seeds were also noted, such as degeneration, mainly in seeds kept at room temperature 25 (± 2 °C), which caused a reduction in the main components of reserves. The -80 °C (ultra freezer) temperature during the two and four months period was efficient in the conservation seed of the tissues and cells, confirming the possibility of using this condition for better conservation of the seeds of this species. [ABSTRACT FROM AUTHOR]

Orchids have a long period of production and need to be under the right conditions. Therefore, in vitro propagation is an alternative to reduce production time. This study aimed to determine the optimal in vitro propagation conditions in two species of orchids, Cattleya maxima Lindl. and Phalaenopsis amabilis (L.) Blume. For this goal, two experiments were carried out: multiplication and rooting, for both species. In the multiplication experiment, the treatments were differentiated according to the complement of MS (Murashige and Skoog medium), banana flour, kinetin or 6-Benzylaminopurine (BAP). Meanwhile, in the rooting experiment, the complements were banana flour, Indol-3-butiric acid (IBA), Naphthaleneacetic acid (NAA) or 2,4-Dichlorophenoxyacetic acid (2,4-D). According to the results, banana flour (50 g.L-1 ) increased the plantlet height in C. maxima (multiplication) and P. amabilis (rooting). Kinetin (0.003 g.L-1 ) and BAP (0.005 g.L-1 ) increased the number of shoots and leaves in C. maxima, in multiplication experiment. In rooting experiment, NAA (0.003 g.L-1 ) increased significantly the number of leaves in C. maxima. The root formation was notably stimulated by banana flour in both species. Likewise, 2,4- D (0.003 g.L-1 ) can cause phytotoxic effects and inhibit root formation. In conclusion, C. maxima was more robust than P. amabilis since in all studied variables the former presented the highest values. Furthermore, C. maxima responds adequately to application of kinetin and BAP to increase the aerial part of the plant, however, they inhibit the root formation. In contrast, kinetin and BAP do not limit root growth in P. amabilis. [ABSTRACT FROM AUTHOR]

Growth and photosynthetic capacity of Cattleya warneri T. Moore seedlings cultivated in vitro were evaluated in two environments: (1) growth room (GR) with constant light, humidity, and temperature; and (2) greenhouse (GH) with variable humidity, temperature, and light intensity and quality. In both environments, two different tissue culture vessel lids were used: transparent plastic lids (TCVplastic) and non-transparent metal lids (TCVmetal). After 11 months of in vitro cultivation, five seedlings from each tissue culture vessel were evaluated for growth and photosynthetic capacity, while the other five seedlings of each tissue culture vessel were transferred to a greenhouse for acclimatization. Increased biomass production in vitro was observed in GH and GR (GH>GR). However, the photosynthetic capacity was not altered by the GH environment, since the net photosynthetic rate at 300 μmol m−2 s−1 (NPR300) was low in the final of period in all treatments. Therefore, the increase in biomass production in C. warneri was mostly dependent on the exogenous carbon source through the addition of sucrose to the culture medium. The use of TCVplasticin vitro improved seedlings' growth in both GR and GH, showing an advantage in relation to TCVmetal. GH environment with quality light spectrum and thermal amplitude, and use of TCVplastic, increased biomass production in vitro and improved the acclimatization process of C. warneri seedlings, which also reduced electricity costs since the use of artificial light and air conditioning is not required. [ABSTRACT FROM AUTHOR]

Among the Orchidaceae is found the Cattleya , an important genus for commercial hybrid production. However, many Cattleya species are facing extinction due to over-collection and habitat loss. Cattleya elongata is a species endemic to Bahia; these plants have attractive brownish-purple tepals and an attractive purple labellum. This species has been submitted to collections; however, it is not easy to grow in vitro , and as such, it is rarely cultured. This work aimed to determine the best conditions for plant production and acclimatization to allow either commercialization or reintroduction. Germinated seeds were sown in three different culture media, Knudson C (Kc), Murashige and Skooge (½-concentration MS) and Vacin and Went (VW) media, and grown for 270 days. The length of the roots and shoots and their fresh matter were determined, and survival in culture media and acclimatization were also scored. The in vitro development of C. elongata was best in the ½-concentration MS and VW media. The best choice for C. elongata propagation was the ½-concentration MS, as they were superior either for in vitro development or for acclimatization. • Cattleya elongata could be grown easily and fast in vitro culture media; • Higher nitrogen and potassium are beneficial for in vitro culture of Cattleya elongata seedlings, producing the vigorous seedlings; • There are differences among the growth and in the acclimatization of seedlings from different culture media. [ABSTRACT FROM AUTHOR]

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The establishment of seed banks is essential for the conservation of cultivated and wild plant species. Cattleya species are economically important, but many of them are at risk of extinction. In this study, we aimed to evaluate the effects of storage temperature on the physiological quality of seeds of seven congeneric species of diverse biomes from the UNOESTE-OSSSU seed bank and the lipid composition. Seeds were split into sub samples, pre-conditioned to 0.03 g H2O g DW−1 for a week over a supersaturated solution of lithium chloride at 23 ± 2 °C and maintained in rubber-sealed vessels for nine months under four storage temperatures: room temperature (23 ± 2 °C), 5 °C, –18 °C and –196 °C. Germination, the germination speed index, and viability based on a tetrazolium test were evaluated at three-month intervals. Lipid profiles were determined by GC-MS in the original seed lots. Different lipid profiles were found among species. Orchid seeds with a low water content could be stored for a short period in all conditions studied and were considered orthodox short-lived seeds. Cattleya rupestris seeds were more tolerant than the congeners to deterioration under all the storage conditions. [ABSTRACT FROM AUTHOR]

The cultivation of orchids requires many procedures, such as managing cultural treatments and fertilization to produce high quality floral stems. The objective of this study was to evaluate the growth of transplanted seedlings of a Cattleya virginia x Brassocattleya pastoral orchid hybrid with Azospirillum brasilense added and different sources of fertilization. The experiment was conducted in a private orchid nursery in Marechal Cândido Rondon, Paraná State, Brazil. The experimental design was randomized blocks in a 2 x 4 factorial scheme (two sources of fertilization x four concentrations of A. brasilense (Masterfix Gramíneas®)), with four repetitions and five plants per repetition, totaling 160 seedlings. The sources of fertilization were Bokashi® as an organic fertilizer and 10-10-10 NPK as a soluble mineral. After ten months, the plants underwent phytotechnical evaluations such as the total number of roots, length of the largest root, number of leaves, length and width of the largest leaf, number of pseudobulbs, number of sprouts, and diameter of the pseudobulb. The use of A. brasilense in the growth of the Cattleya virginia x Brassocattleya pastoral hybrid increased the diameter of the pseudobulb, the number of roots, and the length of the largest root. The inclusion of A. brasilense in the mineral fertilization with 10-10-10 NPK resulted in the greatest number of sprouts. [ABSTRACT FROM AUTHOR]

Cattleya cernua is an epiphytic orchid native of the Atlantic Forest, Cerrado, Caatinga and Pampa. Aiming at the development of an in vitro conservation technology, plants were micropropagated through asymbiotic culture and the influence of different concentrations of sucrose (10, 30, 60 and 90 g L-1) and macronutrients (25, 50 and 100% MS) on survival and development was evaluated. Plant survival ranged between 47 and 100%. The interaction between macronutrients and sucrose influenced plant development. The aerial system of the plants was higher in 100% MS medium combined with 30 or 60 g L-1 of sucrose. The number of roots was higher with reduced macronutrients, combined with 30 or 60 g L-1 of sucrose. The length of the largest root was also higher when macronutrients were reduced but combined with 10 or 30 g L-1 of sucrose. The greatest mass was recorded when 30 g L-1 of sucrose was added to the three salt concentrations. Chlorophyll did not differ between plants grown with 30 or 90 g L-1 of sucrose. We recommend cultivating the plants in MS medium with 30 g L-1 of sucrose for better development of the aerial system. C. cernua can be asymbiotically micropropagated, facilitating ex vitro conservation strategies. [ABSTRACT FROM AUTHOR]

Orchidaceae is a megadiverse botanical family in Brazil, particularly in the Atlantic Forest where it is a priority group for conservation. Parque Nacional do Itatiaia (PARNA Itatiaia) was the first conservation unit established in Brazil, and represents a large and mature remnant of Atlantic Forest. Updated data on richness, distribution and conservation of the Neotropical and ornamental subtribe Laeliinae in the park recently disclosed the occurrence of presumed locally extinct species, but without a taxonomic approach. Thus, we present a comprehensive taxonomic treatment of Laeliinae in the PARNA Itatiaia. The subtribe is represented by six genera and 33 species, which corresponds to about 15% of the orchid flora of PARNA Itatiaia. Epidendrum is the richest genus, with 20 species, followed by Cattleya (6 spp.) and Prosthechea (4 spp.). Species of Laeliinae grow in shady and humid habitats, especially near rivers, at elevations ranging 750-1,200 m, with species richness decreasing with elevation. Several species form small populations (commonly < 10 individuals), which are in need of prompt conservation actions to avoid local extinction. Samples of Laeliinae from PARNA Itatiaia in collections of consulted herbaria were found to be scarce. Variable morphological characteristics, mainly of the lip, distinguishe species of Laeliinae. [ABSTRACT FROM AUTHOR]

Copyright of Agricultural Research in the Tropics / Pesquisa Agropecuária Tropical is the property of Pesquisa Agropecuaria Tropical and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Flower color has been studied in different ecological levels of organization, from individuals to communities. However, it is unclear how color is structured at the intrafloral level. In bee-pollinated flowers, the unidirectional gradient in color purity and pollen mimicry are two common processes to explain intrafloral color patterns. Considering that floral traits are often integrated, usually reflecting evolutionary modules under pollinator-mediated selection, we hypothesize that such intrafloral color patterns are structured by intrafloral color modules as perceived by bee color vision system. Here, we studied the tropical bee-pollinated orchid Cattleya walkeriana , given its intrafloral color complexity and variation among individuals. Considering bee color vision, we investigated if intrafloral color modules arose among intrafloral patches (tip or base of the sepals, petals, and labellum). We expected a separate color module between the labellum patches (the main attractive structure in orchids) and petals and sepals. We measured the color reflectance and calculated the photoreceptor excitation, spectral purity, hue, and the chromatic contrast of the floral structures in the hexagon color model. Spectral purity (saturation) was higher in the labellum tip in comparison to petals and sepals, generating a unidirectional gradient. Labellum base presented a less saturated yellow UV-absorbing color, which may reflect a pollen mimicry strategy. C. walkeriana presented three intrafloral color modules corresponding to the color of petals and sepals, the color of the labellum tip, and the color of labellum base. These color modules were unrelated to the development of floral structures. Given the importance of intrafloral color patterns in bee attraction and guidance, our results suggest that intrafloral patterns could be the outcome of evolutionary color modularization under pollinator-mediated selection. [ABSTRACT FROM AUTHOR]

[Objective]The genetic diversity of Cattleya germplasms was studied to evaluate the relationship between the various species or varieties and to lay the theoretical foundation for identification, classification, genetic map construction and molecular breeding of Cattleya. [Method] Based on 18 Cattleya germplasm resources as the test materials, primers with clear amplified hands, high polymorphism and positive repeatability were selected among the 100 primers for genetic diversity analysis of the samples. GenA1 Ex 6.51 software was utilized for calculating genetic diversity parameters. Clustering analysis was conducted with NTSYS 2. 1 UPGMA method. [ Result] PCR amplification with 6 primers generated 153 bands, by all of which were polymorphic (100 %). Genetic diversity parameters were estimated, average value of observed allele number(Na), number of effective alleles(Ne), Nei's gene diversity(He) and Shannon's information index( I) were 2. 000,1.207,0. 157 and 0.281, respectively. Genetic similarity coefficients ranged between 0.6514 and 0.8991. 18 Cattleya germplasm resources were divided into 6 groups at the similarity coefficient of 0. 749 based on UPGMA cluster analysis. [Conclusion ] The results of ISSR-PCR analysis showed that there were abundant genetic diversity among Cattleya germplasm resources. UPGMA cluster analysis results are basically consistent with the traditional morphological classification results. The 18 Cattleya germplasm resources were divided into 7 genera, which were Cattleya, Crispae, Schomburgkoidea , Falcata, Intermedia Jihizantha and Guarianthe. [ABSTRACT FROM AUTHOR]

Cattlianthe Aurora's Blue Pride is a new hybrid with lavender-blue flower, higher floral count than Cattleya Memoria Jack Hayden and larger than Cattlianthe Portia Baronesa. For the first time, a floral trait is being used in a documented scientific approach to help in the selection of superior plants in a population. [ABSTRACT FROM AUTHOR]

l-Hydroxyproline (Hyp) is a valuable intermediate for the synthesis of pharmaceuticals; consequently, a practical process for its production has been in high demand. To date, industrial processes have been developed by using l-Pro hydroxylases. However, a process for the synthesis of trans-3-Hyp has not yet been established, because of the lack of highly selective enzymes that can convert l-Pro to trans-3-Hyp. The present study was designed to develop a biocatalytic trans-3-Hyp production process. We speculated that ectoine hydroxylase (EctD), which is involved in the hydroxylation of the known compatible solute ectoine, may possess the ability to hydroxylate l-Pro, since the structures of ectoine and 5-hydroxyectoine resemble those of l-Pro and trans-3-Hyp, respectively. Consequently, we discovered that ectoine hydroxylases from Halomonas elongata, as well as some actinobacteria, catalyzed l-Pro hydroxylation to form trans-3-Hyp. Of these, ectoine hydroxylase from Streptomyces cattleya also utilized 3,4-dehydro-l-Pro, 2-methyl-l-Pro, and l-pipecolic acid as substrates. In the whole-cell bioconversion of l-Pro into trans-3-Hyp using Escherichia coli expressing the ectD gene from S. cattleya, only 12.4 mM trans-3-Hyp was produced from 30 mM l-Pro, suggesting a rapid depletion of 2-oxoglutarate, an essential component of enzyme activity as a cosubstrate, in the host. Therefore, the endogenous 2-oxoglutarate dehydrogenase gene was deleted. Using this deletion mutant as the host, trans-3-Hyp production was enhanced up to 26.8 mM from 30 mM l-Pro, with minimal loss of 2-oxoglutarate. This finding is not only beneficial for trans-3-Hyp production, but also for other E. coli bioconversion processes involving 2-oxoglutarate-utilizing enzymes. [ABSTRACT FROM AUTHOR]

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Cattleya xanthina is a Neotropical orchid endemic to the Brazilian Atlantic Rainforest, at high risk of extinction. In this paper, we investigated the effects of different culture media on C. xanthina as well as on their endogenous nitrogen status. Culture media studied: Knudson C (KC), Vacin and Went (VW), and Murashige and Skoog (MS), the latter used at two different concentration (full and half-strength; MS/2). After 180 days, plants were transferred to MS medium with different NAA and BA concentrations. In each treatment, biometric parameters were measured and the endogenous levels of photosynthetic pigments, total protein, nitrate and ammonium ions were quantified. Plants grown on KC medium had the lowest concentration of nitrogen but exhibited the greatest shoot development, production of photosynthetic pigments and total protein. Results of growth regulators showed that the highest concentration of auxin stimulated root development and the production of photosynthetic pigments, and that a higher concentration of cytokinin promoted protein synthesis and the development of shoots. Most successful acclimatization was obtained when a mixture of Sphagnum and Pinus bark was used as the substrate. [ABSTRACT FROM AUTHOR]

Two orthologues of Arabidopsis FOREVER YOUNG FLOWER (FYF), CaFYF1 and CaFYF2, were identified from Cattleya intermedia. To investigate the function of these two genes, we performed ectopic expression of CaFYF1/2 in Arabidopsis. Delayed flower senescence and abscission were observed in 35S::CaFYF1/2 transgenic Arabidopsis plants. Furthermore, once CaFYF1/2 was fused with the strong repressor domain SRDX, severe delayed flower senescence and abscission were observed in 35S::CaFYF1/2+SRDX transgenic Arabidopsis plants. In contrast, when 35S::CaFYF1/2 was converted to a potent activator by fusion with the VP16-AD motif, flower senescence and abscission were promoted in these 35S::CaFYF1/2+VP16 transgenic dominant-negative mutant Arabidopsis plants. These results indicated that similar to Arabidopsis FYF, CaFYF1/2 also act as repressors in controlling floral organ senescence and abscission in transgenic Arabidopsis plants. The delayed senescence and abscission of the flower organs in 35S::CaFYF1/2 and 35S::CaFYF1/2+SRDX transgenic Arabidopsis plants were unaffected by ethylene treatment. Genes of the ethylene signaling and abscission-associated pathways, such as EDF1/2/3/4, BOP1/2, and IDA, were repressed in 35S::CaFYF1/2 and 35S::CaFYF1/2+SRDX transgenic Arabidopsis plants. Furthermore, 35S::CaFYF1/2 and 35S::CaFYF1/2+SRDX transgenic Arabidopsis plants showed additional morphological defects, such as short sepals and petals, which were correlated with the upregulation of the DELLA genes RGA, GAI, RGL1, and RGL2. These results suggested a possible role for Cattleya orchid CaFYF1/2 in controlling floral senescence/abscission by suppressing ethylene signaling and abscission-associated genes as well as controlling flower organ elongation through negative regulation of GA response by activating the expression of the DELLA genes during flower development. [ABSTRACT FROM AUTHOR]

In this study, we isolate and analyse a new set of microsatellite loci for Cattleya walkeriana. Twenty-two primer pairs were screened for C. walkeriana (n = 32) and assessed for their transferability to Cattleya loddigesii (n = 12) and Cattleya nobilior (n = 06). All loci amplified for C. walkeriana; however, for C. loddigesii and C. nobilior, four and five primers, respectively, did not present amplification. The polymorphic loci presented between 2 and 13 alleles per locus for both C. walkeriana and C. loddigesii, with respective averages of 5.1 and 4.2. For C. nobilior, we found between two and five alleles per locus, with an average of 2.6. For C. walkeriana, observed heterozygosity varied from 0.100 to 0.966, whereas expected heterozygosity ranged from 0.097 to 0.900. The observed and expected heterozygosity for C. loddigesii and C. nobilior were also estimated. We found no significant linkage disequilibrium between any pair of loci, and evidence of null alleles at four loci (Cw16, Cw24, Cw30 and Cw31) for C. walkeriana. The combined power to exclude the first parent and combined non-exclusion probability of identity were 0.999 and 2.3 × 10−20, respectively. These new loci can be used in studies of germplasm resources, and assessments of genotypic and genetic diversity and population structure, thus improving the accuracy of such analyses and their applicability in the conservation and protection of these endangered species. [ABSTRACT FROM AUTHOR]