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31.
Summary Pepino (Solanum muricatum), a vegetatively propagated plant from the Andean region used for its edible fruits, has been identified as a potential crop
for greenhouse cultivation in Mediterranean regions. However, attempts for introducing it have been unsuccessful, either because
of the low yield, poor fruit quality, or both. Screening of germplasm under Mediterranean conditions showed that sources of
variation for high yield existed in the cultivated genepool and that wild species S. caripense and S. tabanoense could contribute to a considerable improvement of soluble solids content (SSC) of pepino. Progenies obtained after crossing
genetically distant (AFLP-based) parental clones were heterotic for yield, and allowed the selection of clones with an improved
combination of yield and SSC. As a result of this intraspecific programme, two new improved cultivars (‘Turia’ and ‘Valencia’),
which outperform the rest of cultivars available, have been selected for cultivation in Mediterranean conditions. The interspecific
programme involved the selection of clones with high yield and SSC in backcross generations. The results show that introgression
of genes from the wild species can contribute to improve the SSC of pepino. The backcross programme is in an advanced stage
and new cultivars derived from the interspecific crosses are expected to be released in a near future. New prospects for the
future in pepino breeding include the genetic transformation, the establishment of a genetic map, and the use of the genomic
information from related Solanaceae important crops. All the information obtained is illustrative for the breeding for adaptation
of vegetatively propagated crops. 相似文献
32.
Cheel J Theoduloz C Rodríguez J Saud G Caligari PD Schmeda-Hirschmann G 《Journal of agricultural and food chemistry》2005,53(22):8512-8518
Three E-cinnamic acid glycosides, tryptophan, and cyanidin-3-O-beta-D-glucopyranoside were isolated from ripe fruits of the Chilean strawberry Fragaria chiloensis ssp. chiloensis. 1-O-E-Cinnamoyl-beta-D-xylopyranoside, 1-O-E-cinnamoyl-beta-D-rhamnopyranoside, and 1-O-E-cinnamoyl-alpha-xylofuranosyl-(1-->6)-beta-D-glucopyranose are reported for the first time. The cinnamic acid glycosides and aromatic compound patterns in F. chiloensis fruits were determined by high-performance liquid chromatography (HPLC). HPLC analyses of extracts showed that cyanidin-3-O-beta-D-glucopyranoside and free ellagic acid are present in achenes while the E-cinnamoyl derivatives and tryptophan were identified only in the thalamus. The free radical scavenging effect of the fruit extract can be associated with the anthocyanin content. 相似文献
33.
Nives Ogrinc Tjaša Kanduč Bor Krajnc Urša Vilhar Primož Simončič Lixin Jin 《Journal of Soils and Sediments》2016,16(2):382-395
Purpose
Soil carbon dynamics were studied at four different forest stands developed on bedrocks with contrasting geology in Slovenia: one plot on magmatic granodiorite bedrock (IG), two plots on carbonate bedrock in the karstic-dinaric area (CC and CD), and one situated on Pleistocene coalluvial terraces (FGS).Materials and methods
Throughfall (TF) and soil water were collected monthly at each location from June to November during 2005–2007. In soil water, the following parameters were determined: T, pH, total alkalinity, concentrations of Ca2+ and Mg2+, dissolved organic carbon (DOC), and Cl? as well as δ13CDIC. On the other hand, in TF, only the Cl? content was measured. Soil and plant samples were also collected at forest stands, and stable isotope measurements were performed in soil and plant organic carbon and total nitrogen and in carbonate rocks. The obtained data were used to calculate the dissolved inorganic carbon (DIC) and DOC fluxes. Statistic analyses were carried out to compare sites of different lithologies, at different spatial and temporal scales.Results and discussion
Decomposition of soil organic matter (SOM) controlled by the climate can explain the 13C and 15?N enrichment in SOM at CC, CD, and FGS, while the soil microbial biomass makes an important contribution to the SOM at IG. The loss of DOC at a soil depth of 5 cm was estimated at 1 mol m?2 year?1 and shows no significant differences among the study sites. The DOC fluxes were mainly controlled by physical factors, most notably sorption dynamics, and microbial–DOC relationships. The pH and pCO2 of the soil solution controlled the DIC fluxes according to carbonate equilibrium reactions. An increased exchange between DIC and atmospheric air was observed for samples from non-carbonate subsoils (IG and FGS). In addition, higher δ13CDIC values up to ?19.4?‰ in the shallow soil water were recorded during the summer as a consequence of isotopic fractionation induced by molecular diffusion of soil CO2. The δ13CDIC values also suggest that half of the DIC derives from soil CO2 indicating that 2 to 5 mol m?2 year?1 of carbon is lost in the form of dissolved inorganic carbon at CC and CD after carbonate dissolution.Conclusions
Major difference in soil carbon dynamics between the four forest ecosystems is a result of the combined influence of bedrock geology, soil texture, and the sources of SOM. Water flux was a critical parameter in quantifying carbon depletion rates in dissolved organic and inorganic carbon forms.34.
Anther culture is a convenient technique to obtain androgenic haploid and doubled haploid (DH) plants. In common eggplant
(Solanum melongena), this technique has been used to develop DH pure lines for producing uniform F1 hybrid seed of some commercial varieties.
However, a comprehensive study of the variation of this useful trait among different materials of common eggplant and related
species is still lacking. In this work, we studied the androgenic response of 12 accessions of common eggplant and related
materials from the primary (eggplant complex) and secondary genepools. We cultured anthers of all the accessions under the
same experimental conditions, and studied their competence to produce calli, embryos and plants, as well as the quality and
origin of the embryos produced. In our conditions, anthers of 11 out of the 12 accessions produced somatic calli, whereas
only 5 also produced microspore-derived embryos, with variable results in terms of embryo quality and of frequency of embryo
induction and plant germination. Embryos of responding accessions were initially haploid, and reached the DH status, verified
with SSR markers, after a defined period of culture. In addition to other aspects common to many androgenesis-responsive species,
our results allowed us to extract conclusions particular to common eggplant and relatives, including the difficulty for finding
sources of androgenic competence out of S. melongena, the reduced impact of calli in the production of non-DH individuals, and the need to avoid the occurrence of severe anatomical
and functional problems in the apex of most embryos, which seriously reduces their germinative success. 相似文献
35.
Coleman JN Lotya M O'Neill A Bergin SD King PJ Khan U Young K Gaucher A De S Smith RJ Shvets IV Arora SK Stanton G Kim HY Lee K Kim GT Duesberg GS Hallam T Boland JJ Wang JJ Donegan JF Grunlan JC Moriarty G Shmeliov A Nicholls RJ Perkins JM Grieveson EM Theuwissen K McComb DW Nellist PD Nicolosi V 《Science (New York, N.Y.)》2011,331(6017):568-571
If they could be easily exfoliated, layered materials would become a diverse source of two-dimensional crystals whose properties would be useful in applications ranging from electronics to energy storage. We show that layered compounds such as MoS(2), WS(2), MoSe(2), MoTe(2), TaSe(2), NbSe(2), NiTe(2), BN, and Bi(2)Te(3) can be efficiently dispersed in common solvents and can be deposited as individual flakes or formed into films. Electron microscopy strongly suggests that the material is exfoliated into individual layers. By blending this material with suspensions of other nanomaterials or polymer solutions, we can prepare hybrid dispersions or composites, which can be cast into films. We show that WS(2) and MoS(2) effectively reinforce polymers, whereas WS(2)/carbon nanotube hybrid films have high conductivity, leading to promising thermoelectric properties. 相似文献
36.
37.
Magnetic fields (MFs) have been applied for the first time in orchid micropropagation. Protocorm-like bodies (PLBs) – approximately 3 mm in diameter – first derived from leaf segment culture of Phalaenopsis Gallant Beau ‘George Vazquez’, were subcultured every 2 months, and served as initial explants. The proliferation of Phalaenopsis PLBs in liquid medium in the Miracle Pack® culture system was affected by the action of different intensities and polarities of MFs: 0.1, 0.15 and 0.2 Tesla (T) at North (N) and South (S) poles. The MF of 0.1 T – S resulted in the greatest fresh weight of regenerated PLBs. The average number of neo-PLBs formed per clusters in the PLB treated by MF: 0.1–0.2 T was decreased compared to the control exposed to natural MF (5 × 10−6 T). The proliferation of PLBs under 0.15 T – MF at both N and S poles for 2 and 7 weeks demonstrated that a longer duration of exposure to an MF of 0.15 T, regardless of the polarity, resulted in greater biomass of newly formed PLBs and smaller average number of newly formed PLBs. The S pole of MF had stronger effects on Phalaenopsis PLBs proliferation than the N pole did in all treatments. 相似文献
38.
Zheng Wang Gaoyan Li Songlin He Jaime A. Teixeira da Silva Michio Tanaka 《Scientia Horticulturae》2011
The goal of this study was to evaluate the effect of cold cathode fluorescent lamps (CCFLs) on the growth of Gerbera jamesonii var. ‘Rui Kou’ plantlets in vitro in six different light quality ratios: 100% red CCFL (R), 80% R + 20% blue CCFL (B), 70% R + 30% B, 60% R + 40% B, 100% B and white CCFLs (W). Control radiation was provided by conventional heat-generating plant growth fluorescent lamps (PGFLs). Plantlets under CCFLs showed better plantlet height, SPAD value (i.e., leaf chlorophyll content) and root activity (as assessed by root dehydrogenase activity) than those growing under PGFLs while all other growth parameters were comparable with plants under conventional lighting systems. 相似文献
39.
Sonia Salvo Carlos Muñoz Julio Ávila Jaime Bustos Emilio Cariaga Carolina Silva Gabriel Vivallo 《Scientia Horticulturae》2011
Blueberry exporting is an important activity in Chile, with fresh blueberries commanding the highest prices and being among the most exported products to the European and North American markets. To maintain quality in the centres of consumption, farmers must continuously improve the logistics of harvesting and shipping the blueberries. Thus every year they must calculate the production of the orchard well in advance in order to hire staff and ensure the logistic cold chain. For this calculation they use a count of flower buds and a simple linear model of which the slope parameter represents the number of fruits per bud. However, due to the cost of the counting procedure, some producers count only a fraction of each plant (25%, 50% or 100%), and furthermore they do not know what effect the variety and productive age of the plants may have on the estimation. The objective of this work is to measure the impact of the cultivated variety, the age of the plant in productive years, and the percentage of fruits counted in estimating the parameter fruits per bud. The study involved monitoring 310 plants of different varieties and ages distributed in northern, central and southern Chile (over an area of approximately 700 km × 200 km). The parameter was estimated by fitting simple linear regression models (SLRM) as a function of the number of fruits and flower buds. To evaluate the impact on the parameter, the SLRM was fitted considering the variables observed in all the plants, by percentage counted, by variety and by variety-age of the plant. The major findings indicate significant differences in the estimation of the parameter, suggesting that in order to estimate fruits per bud the whole plant must be counted and its age and variety taken into account. 相似文献
40.
Jaime A. Ocampo-Hernández Patricia Tamez-Guerra Samuel Pineda Fernando Tamayo-Mejía Ariel Guzmán-Franco José I. Figueroa de la Rosa Ana Mabel Martínez 《Journal of pest science》2011,84(4):471-477
Entomopathogenic fungi represent excellent candidates for biological insecticides. Among the many entomopathogenic fungi, Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) is one of the most promising species. Here, we report the results of infection studies performed using four B. bassiana native isolates (Bb37, Bb38, Bb40, and Bb45) compared with the commercial product Mycotrol® (strain GHA) on adult Mexican bean beetle Epilachna varivestis Mulsant (Coleoptera: Coccinellidae), one of the most important pests of bean production in Mexico. First, single concentration (1 × 108 conidia mL?1) assays were carried out using all isolates applied using an immersion method. Examinations at 10 days after inoculation indicated that isolates Bb37, Bb38, and Bb40 significantly reduced adult survival, causing 60–75% mortality compared to the commercial strain GHA (33%) and control (29%). Second, using two selected isolates (Bb37 and Bb40), the mean lethal concentration values (LC50) were estimated for third instar larvae and adult E. varivestis. The LC50 values for Bb37 and Bb40 isolates decreased 5.26-fold and 3.19-fold, respectively, in third instars compared with adults. However, such difference for Bb40 isolate was not significant. Finally, an experiment, to compare the median survival time (MST) values between third instar and adult E. varivestis, was conducted using Bb37 and Bb40 at 1 × 109 conidia mL?1. MST values were significantly reduced against larvae (87 and 100 h) compared with adults (130 and 134 h) by Bb37 and Bb40, respectively. We conclude that native isolates of B. bassiana represent an important alternative for the control of E. varivestis. However, to demonstrate its effectiveness under field conditions, detailed studies are needed. 相似文献