Miscellaneous mistletoe notes, 1–9

Three new species,Cladocolea biflora Kuijt,Struthanthus condensatus Kuijt, andS. lojae Kuijt are described and six new combinations,Cladocolea diversifolia (Benth.) Kuijt,C. lenticellata (Diels) Kuijt,Dendrophthora virgata (Trel.) Kuijt,Korthalsella chilensis (Hook. & Arn.) Kuijt,Phthirusa retroflexa (Ruiz & Pavon) Kuijt, andStruthanthus flexilis (Rusby) Kuijt are proposed. Nomenclature of two more neotropical Loranthaceae,Psittacanthus ramiflorus (DC.) G. Don andStruthanthus interruptus (H.B.K.) Blume is revised.     

Phenotypical temperature adaptation of protein turnover in desert annuals

Protein synthesis and protein degradation rates were measured in three desert annual species at four different experimental temperatures. The taxa chosen for this study were the C₃ winter annuals, Bowlesia incana Ruiz & Pavon and Plantago insularis Eastw., and a C₄ summer annual, Atriplex elegans (Moq.) D. Dietr. Peak rates of protein synthesis correlated well with the preferred habitat temperatures of B. incana and A. elegans; optima occurred at 25 and 35°C, respectively. Plants of P. insularis showed an optimum protein synthesis rate at 35°C; however, this optimum rate was considerably lower than for the other two species. Higher activation energies for protein synthesis tended to parallel adaptation to higher temperature habitats. Responses of protein degradation to temperature in A. elegans and B. incana were consistent with their natural thermal regimes, when evaluated for the transition from 25 to 35°C. Again, protein degradation in P. insularis shows an intermediate response to temperature during the 25 to 35°C transition.     

Analysis of an introgressed Nicotiana tomentosa genomic region affecting leaf number and correlated traits in Nicotiana tabacum

Germplasm from closely related diploid relatives of tobacco (Nicotiana tabacum L.) could be of value for continued genetic modification of this species and for mapping quantitative trait loci (QTLs). We examined near isogenic tobacco lines and hybrids differing for an introgressed genomic region from N. tomentosa Ruiz and Pavon designated as Many Leaves that exhibits a large influence on leaf number and correlated traits. Within a ‘Red Russian’ genetic background, the region acted in an additive to partially dominant fashion to delay flowering time, and increase leaf number, plant height, and green leaf yield. Evidence of epistasis was observed as the region affected these traits to varying degrees in diverse near isogenic hybrids. Fifteen amplified fragment length polymorphism (AFLP) markers of N. tomentosa origin were mapped within a single linkage group of 34.5 cM using a population of 207 BC₁F₁ individuals segregating for Many Leaves. Composite interval mapping produced 2–LOD confidence intervals for likely QTL positions influencing leaf number (3.1 cM region), plant height (2.9 cM region), and days to flowering (3.3 cM region). These intervals were overlapping. Results demonstrate that genomic regions with large genetic effects can be transferred to tobacco from closely related diploid relatives, and that sufficient recombination within these regions may permit mapping of genes controlling quantitative traits. Materials and results described here may be useful in future research to gain insight on the genetic control of the transition from vegetative to reproductive development in Nicotiana.     

Cytogenetic characteristics of wheat lines with modified 1RS.1BL rye-wheat translocation

The higher frequency (almost 90%) of inheritance through pollen of heterozygous hybrids has been shown for the modified 1RS.1BL translocation compared with the 1BL telocentric, and, as a result, the segregations at the Gli-B1 and Glu-B1 loci strongly deviated from the expected values. The distance between the Glu-B1 locus and the centromere was 15.7–24.4 cM. Products of the 1RS_m.1BL translocation “misdivision” were observed at a frequency of 0.05%. Both the Pavon MA1 lines and the winter wheat line with the 1RS_m.1BL _al translocation have shown a significant decrease in the level of homologous chromosome pairing, causing aneuploidy. These lines did not contain any reciprocal translocations with respect to the Kuyal’nik cultivar. A “hybrid desynapsis” has been observed in F₁ hybrids (Kuyal’nik × Pavon MA1) in contrast to analogous hybrids from a winter line by the 1RS_m.1BL _al type. No single case of the 21_Closed ^II formation has been observed among the studied 693 pollen mother cells (PMCs), which would have indicated the presence of pairing between the short arms of the 1RS_m.1BL translocations and the intact chromosome 1B.     

Cytochrome P450-soluble epoxide hydrolase derived linoleic acid oxylipins and cognitive performance in type 2 diabetes

Type 2 diabetes mellitus (T2DM) increases the risk of cognitive decline and dementia. Disruptions in the cytochrome P450-soluble epoxide hydrolase (CYP450-sEH) pathway have been reported in T2DM, obesity and cognitive impairment. We examine linoleic acid (LA)-derived CYP450-sEH oxylipins and cognition in T2DM and explore potential differences between obese and nonobese individuals. The study included 51 obese and 57 nonobese participants (mean age 63.0 ± 9.9, 49% women) with T2DM. Executive function was assessed using the Stroop Color-Word Interference Test, FAS-Verbal Fluency Test, Digit Symbol Substitution Test, and Trails Making Test-Part B. Verbal memory was assessed using the California Verbal Learning Test, second Edition. Four LA-derived oxylipins were analyzed by ultra-high-pressure–LC/MS, and the 12,13-dihydroxyoctadecamonoenoic acid (12,13-DiHOME) considered the main species of interest. Models controlled for age, sex, BMI, glycosylated hemoglobin A1c, diabetes duration, depression, hypertension, and education. The sEH-derived 12,13-DiHOME was associated with poorer executive function scores (F_1,98 = 7.513, P = 0.007). The CYP450-derived 12(13)-epoxyoctadecamonoenoic acid (12(13)-EpOME) was associated with poorer executive function and verbal memory scores (F_1,98 = 7.222, P = 0.008 and F_1,98 = 4.621, P = 0.034, respectively). There were interactions between obesity and the 12,13-DiHOME/12(13)-EpOME ratio (F_1,97 = 5.498, P = 0.021) and between obesity and 9(10)-epoxyoctadecamonoenoic acid (9(10)-EpOME) concentrations (F_1,97 = 4.126, P = 0.045), predicting executive function such that relationships were stronger in obese individuals. These findings suggest that the CYP450-sEH pathway as a potential therapeutic target for cognitive decline in T2DM. For some markers, relationships may be obesity dependent.     

Reproductive and genetic roles of the maternal progenitor in the origin of common wheat (Triticum aestivum L.)

Common wheat (Triticum aestivum L., AABBDD genome) is thought to have emerged through natural hybridization between Triticum turgidum L. (AABB genome) and Aegilops tauschii Coss. (DD genome). Hybridization barriers and doubling of the trihaploid F₁ hybrids’ genome (ABD) via unreduced gamete fusion had key roles in the process. However, how T. turgidum, the maternal progenitor, was involved in these mechanisms remains unknown. An artificial cross‐experiment using 46 cultivated and 31 wild T. turgidum accessions and a single Ae. tauschii tester with a very short genetic distance to the common wheat D genome was conducted. Cytological and quantitative trait locus analyses of F₁ hybrid genome doubling were performed. The crossability and ability to cause hybrid inviability did not greatly differ between the cultivars and wild accessions. The ability to cause hybrid genome doubling was higher in the cultivars. Three novel T. turgidum loci for hybrid genome doubling, which influenced unreduced gamete production in F₁ hybrids, were identified. Cultivated T. turgidum might have increased the probability of the emergence of common wheat through its enhanced ability to cause genome doubling in F₁ hybrids with Ae. tauschii. The ability enhancement might have involved alterations at a relatively small number of loci.     

Piper crocatum Ruiz & Pav. ameliorates wound healing through p53, E-cadherin and SOD1 pathways on wounded hyperglycemia fibroblasts

IntroductionPiper crocatum Ruiz & Pav (P. crocatum) has been reported to accelerate the diabetic wound healing process empirically. Some studies showed the benefits of P. crocatum in treating various diseases but its mechanisms in diabetic wound healing have never been reported. In the present study we investigated the diabetic wound healing activity of the active fraction of P. crocatum on wounded hyperglycemia fibroblasts (wHFs).MethodsBioassay-guided fractionation was performed to get the most active fraction. The selected active fraction was applied to wHFs within 72 h incubation. Mimicking a diabetic condition was done using basal glucose media containing an additional 17 mMol/L D-glucose. A wound was simulated via the scratch assay. The collagen deposition was measured using Picro-Sirius Red and wound closure was measured using scratch wound assay. Underlying mechanisms through p53, αSMA, SOD1 and E-cadherin were measured using western blotting.ResultsWe reported that F_IV is the most active fraction of P. crocatum. We confirmed that F_IV\(7.81 µg/ml, 15.62 µg/ml, 31.25 µg/ml, 62.5 µg/ml, and 125 µg/ml) induced the collagen deposition and wound closure of wHFs. Furthermore, F_IV treatment (7.81 µg/ml, 15.62 µg/ml, 31.25 µg/ml) down-regulated the protein expression level of p53 and up-regulated the protein expression levels of αSMA, E-cadherin, and SOD1.Discussion/conclusionsOur findings suggest that ameliorating collagen deposition and wound closure through protein regulation of p53, αSMA, E-cadherin, and SOD1 are some of the mechanisms by which F_IV of P. crocatum is involved in diabetic wound healing therapy.     

Effects of essential oils on biological attributes of Trichogramma galloi adults

Bioactivity of nine essential oils (EOs) was studied on Anagasta kuehniella eggs in relation to the longevity of females, parasitism and emergence rates and sex ratio in the generations parental, F₁ and F₂ of Trichogramma galloi in comparison to a trade formulation of Azadirachta indica. There was no F₁ and F₂ progeny with Zingiber officinale being the most harmful. The greatest reductions in the parasitism rates (57, 43 and 28%) in the parental generation was caused by Allium sativum, Carapa guianensis and A. indica, respectively. In addition, A. sativum reduced the longevity (4.7 days) in the parental generation and emergence (33%) of F₁. Tested EOs did not affect the sex ratio in the generations F₁ and F₂ and emergence in the F₂. Allium sativum and Z. officinale were non-selective to T. galloi; while A. indica, C. guianensis and P. nigrum oils may compromise the progeny; therefore, their use must be avoided. Citrus sinensis, Mentha piperita, Origanum vulgare, Syzygium aromaticum and Thymus vulgare were selective to T. galloi, and these EOs are promising for IPM programs.     

CHASMOGAMY/CLEISTOGAMY IN TRIODANIS PERFOLIATA (CAMPANULACEAE): SOME CH/CL COMPARISONS IN FITNESS PARAMETERS

The chasmogamous/cleistogamous (CH/CL) breeding system has evolved independently many times, but its ecological role has been studied in few species. In Triodanis perfoliata, we studied the natural phenology of flowering and seed set, how successful CH flowers were at setting seed, whether seed from CH and CL flowers differed in germination behavior, and whether plants derived from these two seed types differed in vigor. Most notably, we found that the later the CH flowers were produced, the fewer seed they successfully matured. In general the two seed types did not show differences in germination behavior, but for some maternal parents the two seed types differed. For these, the CL seed germinated less readily. Finally, there was some indication that plants from CL seed were not as vigorous as those from CH seed.     

Maintenance of photosynthesis and the antioxidant defence systems have key roles for survival of Halopeplis perfoliata (Amaranthaceae) in a saline environment

• Coastal salt marsh plants employ various combinations of morphological and physiological adaptations to survive under saline conditions. Little information is available on salinity tolerance mechanisms of Halopeplis perfoliata, a C3 stem succulent halophyte.
• We investigated the growth, photosynthesis and antioxidant defence mechanisms of H. perfoliata under saline conditions (0, 150, 300 and 600 mM NaCl) in an open greenhouse.
• Optimal shoot succulence, projected shoot area and relative growth rate were obtained in the low (150 mm NaCl) salinity treatment, while growth was inhibited at the highest salinity (600 mm NaCl). The CO₂ compensation point and carbon isotope composition of biomass confirmed C₃ photosynthesis. Increases in salinity did not affect the photosynthetic pigment content or maximum quantum efficiency of PSII of H. perfoliata. Assimilation of CO₂ (A) also remained unaffected by salinity. A modest effect on some gas exchange and photochemistry parameters was observed at 600 mm NaCl. With increasing salinity, there was a continual increase in respiration, suggesting utilisation of energy to cope with saline conditions. Under 300 and 600 mm NaCl, there was an increase in H₂O₂ and MDA with a concomitant rise in AsA, GR content and CAT activity.
• Hence, H. perfoliata appears to be an obligate halophyte that can grow up to seawater salinities by modulating photosynthetic gas exchange, photochemistry and the antioxidant defence systems.

     

Does stigma curvature promote delayed selfing? An experimental investigation in Triodanis perfoliata (Campanulaceae)

• Self‐fertilisation that is delayed until after opportunities for outcrossing have ceased has been argued to provide both the reproductive assurance benefits of selfing and the genetic advantages of outcrossing. In the Campanulaceae, presentation of pollen on stylar hairs and progressive stigma curvature have been hypothesised to facilitate delayed selfing, but experimental tests are lacking. Stigma curvature is common in Campanula, a genus largely characterised by self‐incompatibility, and therefore is unlikely to have initially evolved to promote self‐fertilisation. In derived self‐compatible species, however, stigma curvature might serve the secondary function of delayed selfing.
• We investigated delayed selfing in Triodanis perfoliata, a self‐compatible relative of Campanula. Using floral manipulation experiments and pollen tube observations, we quantified the extent and timing of self‐pollination. Further, we hypothesised that, if stigma curvature provides the benefit of delayed selfing in Triodanis, selection should have favoured retention of self‐pollen through the loss of a stylar hair retraction mechanism.
• Results of a stigma removal experiment indicated that autonomous selfing produces partial seed set, but only some selfing was delayed. Pollen tube observations and a flower senescence assay also supported the finding of partial delayed selfing. Scanning electron microscopy revealed that pollen‐collecting hairs retract during anthesis, which may limit the extent of delayed selfing.
• Delayed selfing appeared to be only partially effective in T. perfoliata. The stylar hair retraction in this species would seem to contradict selection for selfing. We suggest that caution and rigour are needed in interpreting floral traits as adaptive mechanisms for delayed selfing.

     

Polymorphic Microsatellite Markers Transferable Across <Emphasis Type="Italic">Capsicum</Emphasis> Species

Pepper (Capsicum annuum L.) is one of the most important crops in the family Solanaceae. However, the number of polymorphic molecular loci detected in this important crop is far behind that of other cultivated plant species. In the present study, a total of 45 microsatellite primer pairs were developed using Capsicum expressed sequence tags databases. Microsatellite primer pairs were tested using several species of Capsicum and several genera in the family Solanaceae including tomato, potato, eggplant, and tobacco. Results indicated that microsatellite primer pairs amplified genomic targets of C. annuum L., Capsicum baccatum L., Capsicum chacoense L., Capsicum chinense L., Capsicum frutescens L., and Capsicum pubescens Ruiz et Pavon, indicating species transferability within Capsicum. Further analyses revealed that amplicons of these primer pairs segregated 1:2:1 or 3:1 Mendelian fashions in 38 F₂ individuals of pepper. It was also noted that markers derived from sequences containing dinucleotide repeats were generally more polymorphic at the intraspecific level than sequences containing trinucleotide repeats. All the microsatellite primer pairs developed in this study will be useful for marker-assisted selection and mapping studies in pepper.     

Inheritance pattern and expression of resistance to phosphine in larval stage of Tribolium castaneum (Coleoptera: Tenebrionidae)

Resistance developed by Tribolium castaneum (Herbst), a major pest of stored grain and grain products, to phosphine is a serious concern. Treatment of phosphine is given to all the stages (egg, larva, pupa and adult) of insects simultaneously in the infected commodity. Effective resistance management tactics need a proper understanding of expression of resistance in relation to dosage in immature stages including larvae. So, this study was undertaken to understand the genetic basis of phosphine resistance in larval stage of T. castaneum by crossing the resistant and susceptible parents to obtain the F₁, F₂ and the back-cross progenies. The resistant parent had a resistance ratio of 37.75 when compared to the susceptible parent. The susceptibility levels of the reciprocal F₁ hybrids did not show any significant difference indicating autosomal mode of inheritance of resistance. Level of dominance for the reciprocal F₁ hybrids was estimated (-0.70 and ?0.68) which showed that the resistance is expressed as incompletely recessive in larval stage of T. castaneum. χ² analysis showed that the observed and expected mortalities differed significantly (P < 0.05) in most of the concentrations indicating that more than one gene is responsible for phosphine resistance. Two plateaus at ～ 40 % and ～ 90 % mortality levels for the back-cross progeny to the resistant parent further confirmed the involvement of two or more genes in imparting resistance to phosphine. Our results will aid in enhancing the knowledge on the development of resistance to phosphine in the field and thus facilitate in designing suitable resistance management tactics.     

Measuring individual inbreeding in the age of genomics: marker-based measures are better than pedigrees

Inbreeding (mating between relatives) can dramatically reduce the fitness of offspring by causing parts of the genome to be identical by descent. Thus, measuring individual inbreeding is crucial for ecology, evolution and conservation biology. We used computer simulations to test whether the realized proportion of the genome that is identical by descent (IBD_G) is predicted better by the pedigree inbreeding coefficient (F_P) or by genomic (marker-based) measures of inbreeding. Genomic estimators of IBD_G included the increase in individual homozygosity relative to mean Hardy–Weinberg expected homozygosity (F_H), and two measures (F_ROH and F_E) that use mapped genetic markers to estimate IBD_G. IBD_G was more strongly correlated with F_H, F_E and F_ROH than with F_P across a broad range of simulated scenarios when thousands of SNPs were used. For example, IBD_G was more strongly correlated with F_ROH, F_H and F_E (estimated with ⩾10 000 SNPs) than with F_P (estimated with 20 generations of complete pedigree) in populations with a recent reduction in the effective populations size (from N_e=500 to N_e=75). F_ROH, F_H and F_E generally explained >90% of the variance in IBD_G (among individuals) when 35 K or more SNPs were used. F_P explained <80% of the variation in IBD_G on average in all simulated scenarios, even when pedigrees included 20 generations. Our results demonstrate that IBD_G can be more precisely estimated with large numbers of genetic markers than with pedigrees. We encourage researchers to adopt genomic marker-based measures of IBD_G as thousands of loci can now be genotyped in any species.     

Inheritance of Resistance to Bacillus thuringiensis subsp. kurstaki in Trichoplusia ni

The genetic inheritance of resistance to a commercial formulation of Bacillus thuringiensis subsp. kurstaki was examined in a Trichoplusia ni colony initiated from a resistant population present in a commercial vegetable greenhouse in British Columbia, Canada. Progeny of F₁ reciprocal crosses and backcrosses between F₁ larvae and resistant (P_R) and susceptible (P_S) populations were assayed at different B. thuringiensis subsp. kurstaki concentrations. The responses of progeny of reciprocal F₁ crosses were identical, indicating that the resistant trait was autosomal. The 50% lethal concentration for the F₁ larvae was slightly higher than that for P_S, suggesting that resistance is partially recessive. The responses of both backcross progeny (F₁ × P_R, F₁ × P_S) did not correspond to predictions from a single-locus model. The inclusion of a nonhomozygous resistant parental line in the monogenic model significantly increased the correspondence between the expected and observed results for the F₁ × P_R backcross but decreased the correspondence with the F₁ × P_S backcross results. This finding suggests that resistance to B. thuringiensis subsp. kurstaki in this T. ni population is due to more than one gene.     

The classification of the generic segregates of Phrygilanthus (= Notanthera) of the Loranthaceae

The taxonomic composition ofPhrygilanthus has long been a source of confusion. Until recently the genus was considered to be distributed from Mexico, Central and South America, to Australia, New Guinea, and the Philippines. Analyses of floral morphology, inflorescence structure, life form, fruit type, and especially chromosome numbers indicate thatPhrygilanthus, as classically circumscribed, is a highly heterogeneous and artificial assemblage containing elements now referable to the following ten genera:Cecarria, Desmaria, Gaiadendron, Ligaria, Muellerina, Notanthera, Psittacanthus, Struthanthus, Tripodanthus, andTristerix. Phrygilanthus itself is nomenclaturally illegitimate and must be replaced by Notanthera. A synopsis of the genera segregated from thePhrygilanthus group is included. A key to the New World genera of Loranthaceae is also appended as well as a nomenclator indicating the present generic status of taxa at one time or another assigned toPhrygilanthus. One genus,Cecarria, is described as new; five new combinations are made:Cecarria obtusifolia (Merr.) Barlow,Psittacanthus palmeri (Wats.) Barlow & Wiens,Struthanthus panamensis (Rizzini) Barlow & Wiens,Tristerix aphyllus (DC.) Barlow & Wiens, andTristerix grandiflorus (Ruiz & Pavon) Barlow & Wiens.     

Complete Mitochondrial Genome of Anoplocephala magna Solidifying the Species

The 2 species of the genus Anoplocephala (Anoplocephalidae), A. perfoliata and A. magna, are among the most important equine cestode parasites. However, there is little information about their differences at the molecular level. The present study revealed that the mitochondrial (mt) genome of A. magna was 13,759 bp in size and 700 bp shorter than that of A. perfoliata. The 2 species includes 2 rRNA, 22 tRNA, and 12 protein-coding genes each. The size of each of the 36 genes was the same as that of A. perfoliata, except for cox1, rrnL, trnC, trnS2(UCN), trnG, trnH, trnQ, and trnP. In the full mitochondrial genome, the sequence similarity was 87.1%. The divergence in the nucleotide and amino acid sequences of individual protein-coding genes ranged from 11.1% to 16% and 6.8% to 16.4%, respectively. The 2 noncoding regions of the mt genome of A. magna were 199 bp and 271 bp in length, while the equivalent regions in A. perfoliata were 875 bp and 276 bp, respectively. The results of this study support the proposal that A. magna and A. perfoliata are separate species, consistent with previous morphological analyses.     

Eudesmane derivatives from Tessaria integrifolia

Five eudesmane-type sesquiterpenoids were isolated from the methanol extract of the aerial part of Tessaria integrifolia Ruiz. et Pavon (Compositae). Their structures were elucidated on the basis of spectroscopic analysis is well as chemical evidence.     

Relationship of Intracellular Coenzyme F420 Content to Growth and Metabolic Activity of Methanobacterium bryantii and Methanosarcina barkeri

The use of F₄₂₀ as a parameter for growth or metabolic activity of methanogenic bacteria was investigated. Two representative species of methanogens were grown in batch culture: Methanobacterium bryantii (strain M.o.H.G.) on H₂ and CO₂, and Methanosarcina barkeri (strain Fusaro) on methanol or acetate. The total intracellular content of coenzyme F₄₂₀ was followed by high-resolution fluorescence spectroscopy. F₄₂₀ concentration in M. bryantii ranged from 1.84 to 3.65 μmol · g of protein⁻¹; and in M. barkeri grown with methanol it ranged from 0.84 to 1.54 μmol · g⁻¹ depending on growth conditions. The content of F₄₂₀ in M. barkeri was influenced by a factor of 2 depending on the composition of the medium (minimal or complex) and by a factor of 3 to 4 depending on whether methanol or acetate was used as the carbon source. A comparison of F₄₂₀ content with protein, cell dry weight, optical density, and specific methane production rate showed that the intracellular content of F₄₂₀ approximately followed the increase in biomass in both strains. In contrast, no correlation was found between specific methane production rate and intracellular F₄₂₀ content. However, qCH₄(F₄₂₀), calculated by dividing the methane production rate by the coenzyme F₄₂₀ concentration, almost paralleled qCH₄(protein). These results suggest that F₄₂₀ may be used as a specific parameter for estimating the biomass, but not the metabolic activity, of methanogens; hence qCH₄(F₄₂₀) determined in mixed populations with complex carbon substrates must be considered as measure of the actual methanogenic activity and not as a measure of potential activity.