Parental and Heterotic Effects in <Emphasis Type="Italic">Jatropha curcas</Emphasis> L. Seedlings

Jatropha curcas L. (jatropha) is an important undomesticated perennial plant with high potential for sustainable production of food and fuel in tropical and subtropical regions. However, jatropha has no breeding history and genetic improvement of this novel crop is at an early stage. Therefore, it is of utmost importance to understand the significance of parental and heterotic effects that could be exploited in hybrid combinations. The main goal of this study was to assess the parental and heterotic effects at an early plant age in seedling traits. Our objectives were to (i) examine the variation of traits among genotypes, between genetic pools and fecundation types, (ii) investigate the parental and heterotic effects on these traits, and (iii) discuss the exploitation of parental and heterotic effects in jatropha breeding programs. Genotypes from two genetic pools were used to perform intra- and interpool crosses. Data on germination time, plant height, area of cotyledon and primary leaf, chlorophyll content of primary leaf, number of leaves, and shoot dry mass were investigated. Maternal and paternal effects affected the expression of traits at the seedling stage in jatropha. The level of influence depended on the trait and the parents under consideration. Heterotic effects were present for all seedling traits. The largest heterotic effect was found in an interpool cross.     

Establishment of an <Emphasis Type="Italic">Agrobacteriuim</Emphasis>-mediated cotyledon disc transformation method for <Emphasis Type="Italic">Jatropha curcas</Emphasis>

Jatropha curcas contains high amounts of oil in its seed and has been considered for bio-diesel production. A transformation procedure for J. curcas has been established for the first time via Agrobacterium tumefaciens infection of cotyledon disc explants. The results indicated that the efficiency of transformation using the strain LBA4404 and phosphinothricin for selection was an improvement over that with the strain EHA105 and hygromycin. About 55% of the cotyledon explants produced phosphinothricin-resistant calluses on Murashige and Skoog (MS) medium supplemented with 1.5 mg l⁻¹ benzyladenine (BA), 0.05 mg l⁻¹ 3–indolebutyric acid (IBA), 1 mg l⁻¹ phosphinothricin and 500 mg l⁻¹ cefotaxime after 4 weeks. Shoots were regenerated following transfer of the resistant calli to shoot induction medium containing 1.5 mg l⁻¹ BA, 0.05 mg l⁻¹ IBA, 0.5 mg l⁻¹ gibberellic acid (GA3), 1 mg l⁻¹ phosphinothricin and 250 mg l⁻¹ cefotaxime, and about 33% of the resistant calli differentiated into shoots. Finally, the resistant shoots were rooted on 1/2 MS media supplemented with 0.3 mg l⁻¹ IBA at a rate of 78%. The transgenic nature of the transformants was demonstrated by the detection of β-glucuronidase activity in the primary transformants and by PCR and Southern hybridization analysis. 13% of the total inoculated explants produced transgenic plants after approximately 4 months. The procedure described will be useful for both, the introduction of desired genes into J. curcas and the molecular analysis of gene function.     

Leaf-residing <Emphasis Type="Italic">Methylobacterium</Emphasis> species fix nitrogen and promote biomass and seed production in <Emphasis Type="Italic">Jatropha curcas</Emphasis>

Background

Jatropha curcas L. (Jatropha) is a potential biodiesel crop that can be cultivated on marginal land because of its strong tolerance to drought and low soil nutrient content. However, seed yield remains low. To enhance the commercial viability and green index of Jatropha biofuel, a systemic and coordinated approach must be adopted to improve seed oil and biomass productivity. Here, we present our investigations on the Jatropha-associated nitrogen-fixing bacteria with an aim to understand and exploit the unique biology of this plant from the perspective of plant–microbe interactions.

Results

An analysis of 1017 endophytic bacterial isolates derived from different parts of Jatropha revealed that diazotrophs were abundant and diversely distributed into five classes belonging to α, β, γ-Proteobacteria, Actinobacteria and Firmicutes. Methylobacterium species accounted for 69.1 % of endophytic bacterial isolates in leaves and surprisingly, 30.2 % which were able to fix nitrogen that inhabit in leaves. Among the Methylobacterium isolates, strain L2-4 was characterized in detail. Phylogenetically, strain L2-4 is closely related to M. radiotolerans and showed strong molybdenum-iron dependent acetylene reduction (AR) activity in vitro and in planta. Foliar spray of L2-4 led to successful colonization on both leaf surface and in internal tissues of systemic leaves and significantly improved plant height, leaf number, chlorophyll content and stem volume. Importantly, seed production was improved by 222.2 and 96.3 % in plants potted in sterilized and non-sterilized soil, respectively. Seed yield increase was associated with an increase in female–male flower ratio.

Conclusion

The ability of Methylobacterium to fix nitrogen and colonize leaf tissues serves as an important trait for Jatropha. This bacteria–plant interaction may significantly contribute to Jatropha’s tolerance to low soil nutrient content. Strain L2-4 opens a new possibility to improve plant’s nitrogen supply from the leaves and may be exploited to significantly improve the productivity and Green Index of Jatropha biofuel.

     

<Emphasis Type="Italic">Amycolatopsis endophytica</Emphasis> sp. nov., a novel endophytic actinomycete isolated from oil-seed plant <Emphasis Type="Italic">Jatropha curcas</Emphasis> L.

A novel actinomycete, designated KLBMP 1221^T, was isolated from the surface-sterilized seeds of an oil-seed plant Jatropha curcas L. collected from Sichuan Province, south-west China and was characterized taxonomically by using a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequence showed that this strain formed a distinct phyletic line within the radiation of the genus Amycolatopsis. The 16S rRNA gene sequence similarity indicated that strain KLBMP 1221^T was most closely related to Amycolatopsis eurytherma NT202^T (98.9%), Amycolatopsis tucumanensis ABO^T (98.8%), Amycolatopsis thermoflava N1165^T (98.6%) and Amycolatopsis methanolica IMSNU 20055^T (98.5%). Strain KLBMP 1221^T had morphological and chemotaxonomic properties that were consistent with its classification in the genus Amycolatopsis. However, DNA–DNA relatedness data and phenotypic differences clearly distinguished the isolate from its closest relatives. Based on the combined genotypic and phenotypic evidence, it is proposed that strain KLBMP 1221^T be classified as representative of a novel species for which the name Amycolatopsis endophytica sp. nov. is proposed. The type strain is KLBMP 1221^T (= KCTC 19776^T = CCTCC AA 2010003^T).     

Effect of fertilizer application on photosynthesis and oil yield of <Emphasis Type="Italic">Jatropha curcas</Emphasis> L.

The use of Jatropha curcas oil as a source of biofuel has been well-explored. However, the physiological and growth studies of J. curcas have received considerably lesser attention. In this study, leaf gas exchange measurements and leaf nitrogen content were determined for four varieties of J. curcas, grown in the field or in pots. Based on stable carbon isotope analysis (δ¹³C) and gas-exchange studies, J. curcas is a C₃ sun plant and the range of leaf photosynthetic rates (or CO₂ assimilation rates, P _Nmax) were typically between 7 and 25 μmol(CO₂) m⁻² s⁻¹ and light saturation generally occurred beyond 800 μmol(quanta) m⁻² s⁻¹. Higher rates of leaf photosynthesis were generally obtained with the mature leaves. In addition, increased foliar P _Nmax were recorded in potted J. curcas variety Indiana with increasing nitrogen (N) nutrition levels. These plants also showed greater growth, increased leaf N content, higher maximum CO₂ assimilation capacity (P _NhighCO2) and chlorophyll (Chl) content, indicating the potential of optimizing the growth of Jatropha by varying fertilizer nutrient levels. A rapid assessment for leaf N using a nondestructive and portable Chl meter had been established for J. curcas. This approach will allow repeated sampling of the same plant over time and thus enable the monitoring of the appropriate levels of soil fertility to achieve good Jatropha plantation productivity. High N nutrition improved the overall plant oil yield by increasing the total number of fruits/seeds produced per plant, while not affecting the intrinsic seed oil content.     

Molecular cloning and characterization of phospholipase D from <Emphasis Type="Italic">Jatropha curcas</Emphasis>

Phospholipase D (PLD, EC 3.1.4.4) is a key enzyme involved in phospholipid catabolism, initiating a lipolytic cascade in membrane deterioration during senescence and stress, which was cloned from Jatropha curcas L., an important plant species as its seed is the raw material for biodiesels. The cDNA was 2,886 bp in length with a complete open reading frame of 2,427 bp which encoded a polypeptide of 808 amino acids including a putative signal peptide of 53 amino acid residues and a mature protein of 755 amino acids with a predicted molecular mass of 86 kD and a pI of 5.44, having two highly conserved ‘HKD’ motifs. Phylogenetic analysis indicated the J. curcas PLD alpha (JcPLDα) showed a high similarity to other PLD alpha from plants. Semi-quantitative RT-PCR analysis revealed that it was especially abundant in root, stem, leaf, endosperm and flower, weakly in seed. And the JcPLDα was increasedly expressed in leaf undergoing environmental stress such as salt (300 mM NaCl), drought (30% PEG), cold (4°C) and heat (50°C). The JcPLDα protein was successfully expressed in Escherichia coli and showed high enzymatic activities. Maximal activity was at pH 8 and 60°C.     

Changes in leaf epicuticular wax,gas exchange and biochemistry metabolism between <Emphasis Type="Italic">Jatropha mollissima</Emphasis> and <Emphasis Type="Italic">Jatropha curcas</Emphasis> under semi-arid conditions

Jatropha curcas and Jatropha mollissima plants were evaluated under conditions of high (HSM) and low (LSM) soil moisture in a semi-arid environment, as changes in the content and concentration of epicuticular wax and the leaf metabolism which could have a relationship with drought tolerance. Besides epicuticular wax, gas exchange, antioxidant system and biochemical parameters of the photosynthetic metabolism were measured. The epicuticular wax content increased only in J. mollissima leaves 95 % under LSM, when compared with HSM conditions. Therefore, J. curcas invested less in the production of long-chain n-alkanes than did J. mollissima under LSM conditions. J. mollissima plants showed the highest CO₂ assimilation rate during the HSM period compared to J. curcas. Both species showed high stability in some leaf biochemistry products, highlighting the highest sugar content, free amino acids, total soluble protein, and photosynthetic pigments in the leaves of J. mollissima plants under both of the soil moisture conditions. Moreover, the stability and performance of the different parameters, such as morphologic variables, seem to allow J. mollissima plants to tolerate semi-arid conditions.     

Stress-induced curcin-L promoter in leaves of <Emphasis Type="Italic">Jatropha curcas</Emphasis> L. and characterization in transgenic tobacco

Ribosome-inactivating proteins (RIPs) represent a type of protein that universally inactivates the ribosome thus inhibiting protein biosynthesis. Curcin-L was a type I RIP found in Jatropha curcas L.. Its expression could be activated in leaves by treatments with abscisic acid, salicylic acid, polyethylene glycol, temperature 4, 45°C and ultraviolet light. A 654 bp fragment of a 5′ flanking region preceding the curcin-L gene, designated CP2, was cloned from the J. curcas genome and its expression pattern was studied via the expression of the β-glucuronidase (GUS) gene in transgenic tobacco. Analysis of GUS activities showed that the CP2 was leaf specific, and was able to drive the expression of the reporter gene under stress-induction conditions. Analysis of a series of 5′-deletions of the CP2 suggested that several promoter motifs were necessary to respond to environmental stresses.     

<Emphasis Type="Italic">Ty</Emphasis>1<Emphasis Type="Italic">/copia</Emphasis>- and <Emphasis Type="Italic">Ty</Emphasis>3<Emphasis Type="Italic">/gypsy</Emphasis>-like DNA sequences in <Emphasis Type="Italic">Helianthus </Emphasis>species

Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.     

Effects of low nitrogen and drought stresses on proline synthesis of <Emphasis Type="Italic">Jatropha curcas</Emphasis> seedling

Proline is one of the most important osmoregulatory solutes subjected to osmotic stresses. In this study, low nitrogen supply suppressed the dry biomass, leaf area, and proline biosynthesis of the seedlings of the energy plant Jatropha curcas, which could grow in poor, dry soil. Low-nitrogen stress induced JcP5CS mRNA expression and decreased the activity of P5CS enzyme and the content of free proline in leaves of J. curcas seedlings. When the seedlings grown in low-nitrogen conditions were suddenly exposed to PEG-6000 (−1.6 MPa) stress, the expression of JcP5CS gene was highly induced, and both the activity of P5CS and the content of free proline increased and maintained at high levels to mitigate the impact of drought stresses. This may be one of the reasons why J. curcas could adapt to poor and drought conditions.     

Changes in DNA methylation levels during seed development in <Emphasis Type="Italic">Jatropha curcas</Emphasis>

The antiviral action of natural killer (NK) cells is regulated by a wide repertoire of germ-line encoded membrane receptors which recognize the expression of certain self-molecules on target cells. Among the receptors, killer cell immunoglobulin-like receptor (KIR) which recognizes the expression of human leukocyte antigen (HLA) class I has a predominant role in regulating the effector functions of NK cells, particularly in viral infections. We studied a total of 128 hepatitis B virus (HBV) patients (15 acute, 43 asymptomatic, 27 chronic and 43 with other liver diseases) while attending the Department of Medical Gastroenterology, Government Rajaji Hospital, Madurai, India, and 128 ethnic matched control to find the association between the KIR : HLA genes and differential manifestations of HBV. KIR and its ligand HLA polymorphism were identified by DNA-PCR methods. The activatory receptor KIR-2DS1 was significantly elevated in various disease categories, namely asymptomatic, chronic and other HBV, except acute HBV infection. Whereas, KIR 2DS3 in acute and chronic patients and KIR 2DS5 and 3DS1 in asymptomatic individuals. Among various KIR–HLA combinations, homozygous 2DS2:C1 and individuals with 3DSI:BW4 (OR = 3.23, CI = 1.55–6.7, Pc = 0.02) are associated with HBV asymptomatism, while most of the two domain inhibitory receptors with their ligands showed significant risk in other liver diseases. Further, KIR3DL1 : HLA Bw4Iso80 (OR = 3.89, 95% CI = 1.58–9.55, Pc = 0.004) is related with higher risk for asymptomatic infection when compared with chronic HBV. Thus, the select KIR : HLA alleles and combinations seem to direct the NK cell activities and immune response in different directions resulting in varied symptoms and manifestations in the subgroups of HBV-infected patients studied.     

Shoot Bud Proliferation from Axillary Nodes and Leaf Sections of Non-toxic <Emphasis Type="Italic">Jatropha curcas</Emphasis> L.

Protocols for in vitro propagation of non-toxic variety of J. curcas through axillary bud proliferation and direct adventitious shoot bud regeneration from leaf segments have been established. Shoot bud proliferation from axillaries was assessed on an initial basal Murashige and Skoog (MS) salt medium supplemented with different concentrations of benzyladenine (BA), kinetin and thidiazuron (TDZ) followed by subculture to medium with 4.4-8.9 μM BA. Regardless of the concentration of BA in the subculture medium, shoot multiplication rate was optimum (10–12.3) with primary culture on medium supplemented with 2.3–4.5 μM TDZ. Efficient adventitious shoot regeneration from leaf tissues was achieved with culture on medium with 8.9–44.4 μM BA + 4.9 μM indole-3-butyric acid (IBA) followed by transfer to medium supplemented with 8.9 μM BA + 2.5 μM IBA. Similarity index between toxic Indian variety and the non-toxic variety based on 435 RAPD markers was 96.3%. Crossing studies followed by phorbol ester quantitation revealed that outcrosses with toxic J. curcas do not affect the phorbol ester content of seeds borne on the non-toxic variety.     

Stimulation of the growth of <Emphasis Type="Italic">Jatropha curcas</Emphasis> by the plant growth promoting bacterium <Emphasis Type="Italic">Enterobacter cancerogenus</Emphasis> MSA2

A novel Enterobacter cancerogenus MSA2 is a plant growth promoting gamma-proteobacterium that was isolated from the rhizosphere of Jatropha cucas a potentially important biofuel feed stock plant. Based on phenotypic, physiological, biochemical and phylogenetic studies, strain MSA2 could be classified as a member of E. cancerogenus. However, comparisons of characteristics with other known species of the genus Enterobacter suggested that strain MSA2 could be a novel PGPB strain. In vitro studies were carried for the plant growth promoting attribute of this culture. It tested positive for ACC (1-aminocyclopropane-1-carboxylic acid) deaminase production, phytase, phosphate solubilization, IAA (Indole acetic acid) production, siderophore, and ammonia production. The isolate was then used as a inoculant for the vegetative study of Jatropha curcas plant. Enterobacter cancerogenus MSA2 supplemented with 1% carboxymethylcellulose showed overall plant growth promotion effect resulting in enhanced root length (124.14%), fresh root mass (81%), fresh shoot mass (120.02%), dry root mass (124%), dry shoot mass (105.54%), number of leaf (30.72%), chlorophyll content (50.41%), and biomass (87.20%) over control under the days of experimental observation. This study was designed for 120 days and was in triplicate and the data was collected at every 30 days.     

Revision of the <Emphasis Type="Italic">Serrulati</Emphasis> species of <Emphasis Type="Italic">Penstemon</Emphasis> section <Emphasis Type="Italic">Saccanthera</Emphasis> subsection <Emphasis Type="Italic">Serrulati</Emphasis>

A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.     

<Emphasis Type="Italic">Galleria</Emphasis><Emphasis Type="Italic">mellonella</Emphasis> are Resistant to <Emphasis Type="Italic">Pneumocystis</Emphasis><Emphasis Type="Italic">murina</Emphasis> Infection

Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.     

Molecular characterization of intra-population variability of <Emphasis Type="Italic">Jatropha curcas</Emphasis> L. using DNA based molecular markers

Jatropha curcas L. (Euphorbiaceae) has acquired a great importance as a renewable source of energy with a number of environmental benefits. Very few attempts were made to understand the extent of genetic diversity of J. curcas germplasm. In the present study, efforts were made to analyze the genetic diversity among the elite germplasms of J. curcas, selected on the basis of their performance in field using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeats (SSR). The plants were selected on the basis of height, canopy circumference, number of seeds per fruit, weight of 100 seeds, seed yield in grams per plant and oil content. Out of 250 RAPD (with 26 primers), 822 AFLP (with 17 primers) and 19 SSR band classes, 141, 346 and 7 were found to be polymorphic, respectively. The percentage polymorphism among the selected germplasms using RAPD, AFLP and SSR was found to be 56.43, 57.9, and 36.84, respectively. The Jaccard’s similarity coefficient was found 0.91, 0.90 and 0.91 through RAPD, AFLP and SSR marker systems, respectively. Principle component analysis (PCA) and dendrogarm analysis of genetic relationship among the germplasm using RAPD, AFLP and SSR data showed a good correlation for individual markers. The germplasm JCC-11, 12, 13, 14 and 15 whose yield found to be high were clustered together in dendrogram and PCA analysis though JCC11 is geographically distinct from others. In overall analysis JCC6 (in RAPD), JCC8 (in AFLP) and JCC 6 and JCC10 (in SSR) were found genetically diverse. Characterization of geographically distinct and genetically diverse germplasms with varied yield characters is an important step in marker assisted selection (MAS) and it can be useful for breeding programs and QTL mapping.     

<Emphasis Type="Italic">Quinua</Emphasis> and Relatives (<Emphasis Type="Italic">Chenopodium</Emphasis> sect.<Emphasis Type="Italic">Chenopodium</Emphasis> subsect.<Emphasis Type="Italic">Celluloid</Emphasis>)

Traditionally viewed as an Andean grain crop,Chenopodium quinoa Willd. includes domesticated populations that are not Andean, and Andean populations that are not domesticated. Comparative analysis of leaf morphology and allozyme frequencies have demonstrated that Andean populations, both domesticated(quinua) and free-living(ajara), represent an exceptionally homogeneous unit that is well differentiated from allied domesticates of coastal Chile(quingua) and freeliving populations of the Argentine lowlands(C. hircinum). This pattern of relationships indicates that Andean populations represent a monophyletic crop/weed system that has possibly developed through cyclic differentiation (natural vs. human selection) and introgressive hybridization. Relative levels of variation suggest that this complex originated in the southern Andes, possibly from wild types allied withC. hircinum, with subsequent dispersal north to Colombia and south to the Chilean coast. Coastal populations were apparently isolated from post-dispersal differentiation and homogenization that occurred in the Andes. Other data point toward a center of origin in the northern Andes with secondary centers of genetic diversity subsequently developing in the southern Andes and the plains of Argentina. Comparative linkage of South American taxa, all tetraploid, with North American tetraploids of the subsection will eventually clarify this problem. While the possibility of a direct phyletic connection betweenC. quinoa and the Mexican domesticate(C. berlandieri subsp. nuttalliae,) cannot be excluded, available evidence indicates that the latter represents an autonomous lineage that is associated with the basal tetraploid, C. b. subsp.berlandieri, through var.sinuatum, whereas South American taxa show possible affinities to either var. zschackei or var.berlandieri. An extinct domesticate of eastern North America,C. b. subsp.jonesianum, represents either another instance of independent domestication, possibly from subsp. b. var.zschackei, or a northeastern outlier of subsp.nuttalliae.     

Biosynthesis and characterization of copolymer poly(3HB-<Emphasis Type="Italic">co</Emphasis>-3HV) from saponified <Emphasis Type="Italic">Jatropha curcas</Emphasis> oil by <Emphasis Type="Italic">Pseudomonas oleovorans</Emphasis>

Polyhydroxyalkanoates (PHAs) are naturally occurring biodegradable polymers with promising application in the formulation of plastic materials. PHAs are produced by numerous bacteria as energy/carbon storage materials from various substrates, including sugars and plant oils. Since these substrates compete as food sources, their use as raw material for industrial-scale production of PHA is limited. Therefore, efforts have been focused on seeking alternative sources for bacterial production of PHA. One substrate that seems to have great potential is the seed oil of Jatropha curcas plant. Among other favorable properties, J. curcas seed oil is non-edible, widely available, and can be cheaply produced. In this study, Pseudomonas oleovorans (ATCC 29347) was grown in a mineral salt medium supplemented with saponified J. curcas seed oil as the only carbon source under batch fermentation. Optimum PHA yield of 26.06% cell dry weight was achieved after 72 h. The PHA had a melting point (T _m) between 150 and 160°C. Results of polymer analyses by gas chromatography/mass spectrometry (GC/MS) identified only the methyl 3-hydroxybutanoate monomeric unit. However, electrospray ionization–time of flight mass spectroscopy (ESI–TOF MS) confirmed that the PHA was a copolymer with the characteristic HB/HV peaks at m/z 1155.49 (HB) and 1,169, 1,184–1,194 (HV). The data were further supported by¹H and ¹³C NMR analysis. Polymer analysis by gel permeation chromatography (GPC) indicated a peak molecular weight (MP) of 179,797, molecular weight (M _W) of 166,838, weight number average mass (M _n) of 131,847, and polydispersity (M _w/M _n) of 1.3. The data from this study indicate that J. curcas seed oil can be used as a substrate to produce the copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3HB-co-3HV).     

<Emphasis Type="Italic">Diplazium</Emphasis> hybrids involving <Emphasis Type="Italic">D. plantaginifolium</Emphasis> and <Emphasis Type="Italic">D</Emphasis>. <Emphasis Type="Italic">ternatum</Emphasis> from Mexico and Central America

Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile.