首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Diploid wild potato species, classified as 1EBN (Endosperm Balance Number), do not cross with tetraploid or diploid forms ofS. tuberosum Gp. Tuberosum. The crossing of 2n pollen producing 1EBN clones as well as chromosome-doubled 1EBN clones with Gp. Tuberosum haploids was initiated to overcome this hybridization barrier. The screening of eleven 1EBN species,S. brachistotrichum, S. bulbocastanum, S. cardiophyllum, S. chancayense, S. commersonii, S. etuberosum, S. fernandezianum, S. jamesii, S. mochicense, S. pinnatisectum andS. trifidum, resulted in the identification of 2n pollen producers in eight of the species examined. Direct hybridization with Gp. Tuberosum haploids utilizing the above-mentioned crossing scheme was successful withS. chancayense andS. commersonii. The hybrids obtained, however, were male and female sterile. Abnormal microsporogenesis in the hybrids was postulated to be the result of an interaction between Gp. Tuberosum cytoplasm and nuclear genes contributed by the 1EBN male parent. Analyses of the growth of 1EBN species’ pollen tubes in the stigma/style of Gp. Tuberosum haploids were also conducted. Interspecific incompatibilities were observed with the most severe forms found with the use of species in the Series Etuberosa. The use of the Endosperm Balance Number theory can aid in designing crosses which overcome barriers to successful endosperm development. Sterilities in the hybrids obtained as well as interspecific incompatibilities will also need to be addressed, however, before 1EBN species germplasm can be successfully utilized for the improvement of the cultivated potato.  相似文献   

2.
Mature seeds of four Lupinus species,L. albus, L. angustifolius, L. luteus andL. mutabilis, have been analysed comprehensively to evaluate their potential for nutrition. Particular interest attaches to the comparison betweenlupinus species and soyabeans. All species are rich in high-quality protein, as judged from amino-acid profiles,In vitro studies indicate high levels of digestibility and imply the presence of few interfering factors. In contrast to many other legumes, lupinseeds are free of both protease inhibitors and haemagglutinins. Only one factor, a C-glycosyl poly-hydroxy flavone, which could conceivably interfere with protein absorption, has been identified. Lupinseed could possibly be developed as an oilseed crop, though oil contents are currently somewhat lower than those of soyabeans. The composition of lupinseed oil is similar to that of soyabean oil, both being limited in quality by the presence of linolenic acid. The bright yellow colour of the partially refined oil is due to the presence of the two carotenoids, β-carotene and zeaxanthin. Lupinseed is well-known to contain toxic alkaloids of the quinolizidine group. However, intensive breeding programmes involving all four named species have been in progress for many years. At least in the cases of the first three species, cultivars have been developed that are virtually alkaloid-free. Alkaloid profiles are of interest in being decisive chemotaxonomic indicators of species. The pyrimidine bases responsible for inducing favism through the consumption ofVicia faba are absent from lupinseed. Like soyabeans, lupinseed invariably contains a range of chemically complex saponins. Concentrations in the seed are of a similar order, but it is doubtful whether these should be considered significant anti-nutritional factors for Man. Lupinseeds contain a range of oligosaccharides—raffinose, stachyose and verbascose —which correspond with the flatus factors present in soyabeans and many other legumes. Levels, however, are no higher than those found in soyabeans.  相似文献   

3.
High performance ethylene propylene diene methylene elastomer (EPDM)/calcium carbonate (CaCO3)/aluminum triacrylate (ALTA) hybrids have been prepared by a melt compounding process. The mechanical properties of the peroxide cured EPDM/CaCO3/ALTA vulcanizates were investigated by tensile, hardness, resilience, abrasion and fatigue life tests. The results showed that the ALTA can greatly improve the modulus at 100 %, tensile strength, abrasion resistance and fatigue life of the EPDM/CaCO3/ALTA vulcanizates, while retaining their high elongation at break. ALTA as a reactive filler had accelerating effect on the vulcanization reaction of and increased the crosslink density of the EPDM/CaCO3 composites. This phenomenon is due to increasing the ionic bonds arise from both homo-polymerization of ALTA and graft co-polymerization of it onto the EPDM. Scanning electron microscopy (SEM) revealed the presence of ALTA causes to the roughness of the fracture surface of CaCO3-filled EPDM compounds demonstrating high interaction between the fillers and EPDM improved by introduction of ALTA. Dynamic mechanical analysis revealed that the glass transition temperature (T g ) and dissipation peak (tan δ) of EPDM composites decreases with increasing ALTA content. Decrease in tan δ value and inward shifting of T g were related to improved interaction of filler and EPDM.  相似文献   

4.
It is mandatory to assess the allergenic potential of genetically modified (GM) crops before their commercialization. Recently, a transgene [Calcineurin B-like (CBL) protein] has been introduced into tobacco plant to make the crop salt resistance. Therefore, it was felt necessary to assess the allergenic potential of the cbl gene product, which was introduced and expressed in Nicotiana tabacum (tobacco) plant and compared the allergenic effects with the wild-type (WT) counterpart. Bioinformatic analysis revealed that there was no significant sequence homology with known allergens. Also, no difference between the protein digestibility profiles of GM and WT tobacco was found. Rapid digestion of CBL protein (Mol Wt 35 kDa) by simulated gastric fluid (SGF) indicated reduced chances of this protein to induce allergenicity. In addition, BALB/c mice sensitized by intraperitoneal administration of WT and GM tobacco protein showed comparable levels of clinical score, specific IgE, IgG1, histamine level, similar effect on different organs as well as IgE binding proteins. These findings indicate that insertion of cbl gene in tobacco did not cause any additional allergic risk to consumer and the GM and native tobacco proteins behave similarly in both in vitro and in vivo situations even after genetic modification.  相似文献   

5.
Bison, a new red potato, was introduced by North Dakota State University. This new red variety has smooth tuber type and bright red skin color. Bison yields somewhat less than Norland and Red Pontiac but the advantage of Bison over these two varieties is its uniformity and bright red color. Bison is about medium in total solids and makes chips comparable in color to Norchip but lighter in color than Kennebec. Bison is resistant to race 0 of the late blight organismPhytophthora infestans, but susceptible to race 1–4.  相似文献   

6.
Potato spindle tuber viroid (PSTV) caused albinism in the new growth of Rutgers tomato under continuous light. The albinism response was obtained with 4 isolates causing severe symptoms in tomato and with 1 mild isolate which is normally symptomless. Rutgers tomato inoculated with the 4 severe strains of PSTV developed typical ‘bunchy top’ symptoms in 12 to 16-hr day lengths. Symptoms developed slower and much less distinctly on plants incubated in 6-hr days. New growth in PSTV-infected plants was green in short days (12-hr illumination) and chlorotic to white in continuous light. Infectivities of extracts from white portions of plants were from 3 to 10 times greater than those from green portions of infected plants. Albino symptoms also developed in other tomato varieties when inoculated with PSTV and kept under continuous light. Albinism was most pronounced under continuous light at 30°C, somewhat less intense at 24°, and at 16°, new growth of infected leaves and stems remained green. Albinism did not develop in otherSolanum species which are symptomless hosts of PSTV nor in seedling potato plants grown in continuous light.  相似文献   

7.
Collembola and mites from the lesions of tubers infected with the acid scab organism were tested for the presence of fungal potato pathogens.Streptomyces spp. were found on and in the bodies of these arthropods.Verticillium albo-atrum was present on the external surface and in the body of the Collembola. Various other soil-inhabiting fungi which are not known to be potato pathogens and which were found on and in the bodies of these arthropods are noted.  相似文献   

8.
9.
The pollination behavior of bumblebees and honey bees was studied on potato flowers in screened enclosures and in the field. In enclosures, the domestic honey bee (Apis mellifera L.) and the bumblebee species,Bombus fervidus Fabricius, seemed to lack any “cue” to initiate visitation of the flowers. When honey was placed on a few flowers, visitation was stimulated. The honey bee tore and chewed at the anther cone to collect pollen, whileB. fervidus probed for nectar which was not present. Shortly afterward, both species ceased visitation and could not be induced to visit further, regardless of the honey stimulus. Neither species was effective as a pollinator. It is concluded that neither species will be useful for large-scale crossing of potato populations. However, another bumblebee species,Bombus impatiens Cresson, is very effective in pollinating potatoes in the field. Manipulating the behavior of such indigenous populations of bumblebees is likely to be the most effective method of exploiting insect pollination in the potato.  相似文献   

10.
Phenolic compounds in Type A glandular trichomes of two insectresistant potato species were separated and identified using a combination of high pressure liquid chromatography (HPLC), UV-visible spectrometry, and1H proton nuclear magnetic resonance (NMR) procedures. Type A trichomes ofSolanum berthaultii andS. polyadenium contained a phenolic compound tentatively identified as the glucose ester of p-hydroxyphenylpropionic acid. Its presence in trichomes of both species suggests that this compound may play a major role in formation of the brownish, insect entrapping exudate characteristic of trichome-mediated insect resistance in these species. Chlorogenic acid, a major phenolic constituent of Type A trichomes ofSolanum polyadenium was not detected in trichomes of 5.berthaultii. The exclusive presence of chlorogenic acid in trichome exudates ofS. polyadenium may be responsible, at least in part, for the greater levels of insect entrapment by this species, compared with that ofS. berthaultii.  相似文献   

11.
Norchief is a medium late maturing, red variety with high total solids. In yield, the new variety is quite comparable to Red Pontiac and La Rouge but higher than Norland. Norchief has shown a certain degree of field tolerance to potato flea beetle,Epitrix cucumeris.  相似文献   

12.
Tuber-bearingSolanum species described since 1753 are listed alphabetically. A three-letter abbreviation for numerous species not included in Simmonds (1963) are proposed. Some pertinent taxonomic notes are provided for all species names. The systems of classification proposed by S.M. Bukasov, D.S. Correll, J.G. Hawkes, and C.M. Ochoa have been used to determine the current taxonomic status of each species.  相似文献   

13.
4′-Geranyloxyferulic (GOFA) and boropinic acid have been discovered during the last decade as interesting phytochemicals having valuable pharmacological effects as cancer chemopreventive, anti-inflammatory, neuroprotective, and anti-Helicobacter pylori agents. A reverse-phase HPLC-UV/Vis method for the separation and quantification of the title oxyprenylated ferulic acid derivatives in extracts obtained from peels of nine edible Citrus and Fortunella fruits was successfully applied. Concentration values showed a great variation between the different species, being orange (C. sinensis) the fruit richest in GOFA (0.141?±?0.011 mg/g of exocarp fresh weight) and kumquat (Fortunella japonica) the one in which boropinic acid was recorded as the most abundant phytochemical (0.206?±?0.002 mg/g of exocarp fresh weight). Both secondary metabolites were not detected only in three species. The set-up methodology showed limits of quantification (LOQ) values, that were able to selectively quantify both GOFA and boropinic acid. Results described herein depict a potential chemopreventive dietary feeding role for the Rutaceae spp. under investigation.  相似文献   

14.
The inheritance of trichome density and droplet size was investigated in diploid and tetraploid crosses. In haploidTuberosum ×Solanum berthaultii and (S.phureja ×haploid Tuberosum) × S.berthaultii crosses, droplet size on type B trichomes was small or droplets were lacking on F1 hybrids. Parental phenotypes were recovered in the F2 and backcross generations. Trichome density was more variable within a clone that was droplet size. Density of both type A and type B trichomes appears to be under the control of small numbers of genes, as parental phenotypes were recovered in the F2 and backcross generations. The variation observed for each of the three traits studied could not be explained by hypotheses based on the segregation of one or two loci. The insect resistance ofSolanum berthaultii appears to be due to the interaction of several chemical and physical factors, thus potato breeders should handle it as a quantitatively inherited trait.  相似文献   

15.
An Andean origin of Phytophthora infestans was originally based on written records, and recently inferred from mitochondrial and nuclear gene genealogies, which emphasize a common South American origin of the European isolates, and absence of the I-b haplotype in Mexico (recently identified in Tlaxcala, Mexico). In order to compare such results, we sequenced the nuclear genes β-tubulin, Ras, and Intron Ras, and rDNA ITS regions in 24 P. infestans genotypes isolated, identified, and selected, during three crop growing cycles in Chapingo, Mexico. The pathogen showed homology and 100 % sequence similarities to the ones reported for the Andes and Europe β-tubulin, Ras, and Intron Ras genes. Results for the ITS region were inconclusive. The molecular oomycete similarities from the three geographical regions (South America, Europe, and Mexico), and the Mexican genotypes characteristics reported in the species supports the hypothesis of the location of P. infestans diversity and a center of dispersal in the central highlands of Mexico.  相似文献   

16.
Two hundred thirty-two plant selections (species and varieties) were tested for susceptibility to the potato spindle tuber ‘virus’ (PSTV). One hundred thirty-eight selections were found to be susceptible to PSTV but no ‘virus’ was recovered from the remaining 94. Susceptible plants were found in the families Boraginaceae, Campanulaceae, Caryophyllaceae, Compositae, Convolvulaceae, Dipsaceae, Sapindaceae, Scrophulariaceae, Solanaceae, and Valerianaceae. Most of the susceptible selections were symptomless carriers of PSTV. Visible symptoms were produced by both mild and severe strains of PSTV inLycopersicon esculentum cv. Allerfruheste-frëiland,Scopolia anomala, S. corniolica, S. lurida, S. sinensis,S. stramonifolia, S. tangutica, Solanum aviculare, andS. avicular var.albiforme; and only by the severe strain inGynura aurantica, Petunia hybrida var. Burpee Blue, andSolanum depilatum. Temperature of 21.1-22.8 C (70-73 F) with a light intensity of about 400 ft-c favored local lesion development inScopolia sinensis. S. sinensis appeared to be more susceptible than otherScopolia species.  相似文献   

17.
Daniel-Navan is a new potato cultivar suitable for the spring crop (between February and July) in the Negev region of Israel, and having a high yielding potential with excellent tuber appearance. The cultivar is resistant to heat stress, Verticillium wilt (V. dahliae) and early blight (Alternaria solani). Tubers of Daniel-Navan are oval, white-skinned, with creamy-white flesh, free of deformities, and growth cracks. It has a high dry matter content (22.7%) and boils and bakes well. The marketable yield of Daniel-Navan obtained at maturity consistently surpasses that of Desiree, the control. Daniel-Navan is a main crop cultivar bred and selected by the Horticultural and Plant Breeding Station, Northern Ireland, and the Agricultural Research Organization, Gilat Experiment Station, Israel. Owing to its high yielding performance and tuber quality, this cultivar could be suitable for use in regions with a hot climate.  相似文献   

18.
Fifty-seven tuber-bearingSolanum progenies including species and interspecific hybrid derivatives were evaluated for resistance to green peach aphid (GPA),Myzus persicae (Sulzer), using an excised leaflet test. The progenies segregated for resistance and most contained some highly resistant clones. Resistance appeared to be partially dominant and genotype-environment interaction was low. Heritability estimates of 50–60 percent were obtained from both diploid and tetraploid populations.  相似文献   

19.
Elba is a high yielding cultivar which combines resistance to the golden nematode, foliar infection byPhytophthora infestans andAlternaria solani, andVerticillium wilt. Elba is a late maturing tablestock cultivar especially well adapted to organic soils. In small plots and on farmers’ fields it has demonstrated its worth in reducing the need for foliar fungicides to prevent blight.  相似文献   

20.
A series of O-carboxymethyl chitosan sodium salt (NaCMCh) with different degree of substitution (DS) of -CH2COONa agent were successfully prepared by altering the reaction temperature and time. Both fourier transform infrared spectroscopy (FTIR) and 13C-Nuclear Magnetic Resonance (13C-NMR) were used to study the structure of NaCMCh. And the impact of DS on the antibacterial activity of NaCMCh was investigated. Then, the NaCMCh with optimal antibacterial activity was selected to prepare NaCMCh/cellulose fibers in N-methylmorpholine-N-oxide (NMMO) system. The structure, crystallization behavior, thermal property and morphology of obtained fibers were carefully studied with FTIR, Wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), thermal gravimetric (TG) and scanning electron microscope (SEM), respectively. Meanwhile, the antibacterial activity as well as mechanical properties of resultant fibers was also investigated. The results demonstrated that the fibers had strong antibacterial activity against Escherichia coli (E. coli), acceptable mechanical properties and good water retention.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号