29,928 research outputs found

    Вариабельность жирнокислотного состава рапсового масла: классическая селекция и биотехнология

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    Проанализированы проблемы и достижения в селекции масличного рапса Brassica napus L. var. оleifera, направленной на изменение состава жирных кислот в масле семян, с использованием традиционных и генноинженерных подходов. Отмечено, что для дальнейшего прогресса в этой области оптимальным является сочетание биотехнологических разработок и методов классической селекции.Проаналізовано проблеми і досягнення в селекції олійного ріпака Brassica napus L. var. оleifera, спрямованої на змінення складу жирних кислот в насіннєвій олії, з використанням традиційних та генноінженерних підходів. Зазначено, що для подальшого прогресу в даній галузі оптимальним є поєднання біотехнологічних розробок і методів класичної селекції.The problems and achievements in the rapeseed Brassica napus L. var. oleifera breeding directed on the change of fatty acid composition in seed oil with the use of traditional and genetic engineering approaches are analyzed. It is noticed that the combination of biotechnological workings out and methods of classical breeding is the optimum for the further improvement of rapeseed oil composition

    Valor nutricional e potencial nutracêutico de inflorescências de couve-nabo (Brassica napus var napus) e couve-tronchuda (Brassica oleraceae var costata).

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    Neste trabalho, avaliou-se a composição nutricional e o potencial nutracêutico, nomeadamente antioxidante, dos grelos, inflorescências da couve-nabo (Brassica napus L. var. napus) e dos espigos, inflorescências da couve-tronchuda (Brassica oleracea L. var. costata). As duas variedades de Brassica estudadas mostraram ser verduras nutricionalmente equilibrados, em particular os espigos que mostraram conter teores mais elevados de humidade, proteínas, energia, lípidos, β-caroteno e vitamina C. Os grelos revelaram maiores teores de cinzas, glúcidos totais, açúcares livres (incluindo frutose, glucose, sacarose e rafinose), ácido gordo n-3 essencial, ácido α- linolénico, as melhores razões PUFA/SFA e ácidos gordos n-6/n-3, tocoferóis, licopeno, clorofilas, fenóis, flavonóides, apresentando também mais propriedades antioxidantes

    Origins of the amphiploid species Brassica napus L. investigated by chloroplast and nuclear molecular markers

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    Background: The amphiploid species Brassica napus (oilseed rape, Canola) is a globally important oil crop yielding food, biofuels and industrial compounds such as lubricants and surfactants. Identification of the likely ancestors of each of the two genomes (designated A and C) found in B. napus would facilitate incorporation of novel alleles from the wider Brassica genepool in oilseed rape crop genetic improvement programmes. Knowledge of the closest extant relatives of the genotypes involved in the initial formation of B. napus would also allow further investigation of the genetic factors required for the formation of a stable amphiploid and permit the more efficient creation of fully fertile re-synthesised B. napus. We have used a combination of chloroplast and nuclear genetic markers to investigate the closest extant relatives of the original maternal progenitors of B. napus. This was based on a comprehensive sampling of the relevant genepools, including 83 accessions of A genome B. rapa L. (both wild and cultivated types), 94 accessions of B. napus and 181 accessions of C genome wild and cultivated B. oleracea L. and related species. Results: Three chloroplast haplotypes occurred in B. napus. The most prevalent haplotype (found in 79% of accessions) was not present within the C genome accessions but was found at low frequencies in B. rapa. Chloroplast haplotypes characteristic of B. napus were found in a small number of wild and weedy B. rapa populations, and also in two accessions of cultivated B. rapa 'brocoletto'. Whilst introgression of the B. napus chloroplast type in the wild and weedy B. rapa populations has been proposed by other studies, the presence of this haplotype within the two brocoletto accessions is unexplained. Conclusions: The distribution of chloroplast haplotypes eliminates any of the C genome species as being the maternal ancestor of the majority of the B. napus accessions. The presence of multiple chloroplast haplotypes in B. napus and B. rapa accessions was not correlated with nuclear genetic diversity as determined by AFLPs, indicating that such accessions do not represent recent hybrids. Whilst some chloroplast diversity observed within B. napus can be explained by introgression from inter-specific crosses made during crop improvement programmes, there is evidence that the original hybridisation event resulting in to B. napus occurred on more than one occasion, and involved different maternal genotypes

    Efekat Ni na koncentraciju najzastupljenijih esencijalnih katjona u nekim vrstama iz roda Brassica

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    Some plants from the genus Brassica have the ability to tolerate excessive concentrations of heavy metals, including Ni. Considering the fact that Ni is a very toxic element for living beings we wanted to examine its influence on some species from genus Brassicaceae. The aim of this study was to investigate the effect of Ni on distribution and accumulation of essential macronutrients from the standpoint of food quality and phytoremediation potential. Experiments were performed using winter (W) and spring (S) varieties of rapeseed (Brassica napus, L.), white mustard (Brassica alba, L.), black mustard (Brassica nigra, L.) and turnip (Brassica rapa, L.). The seeds were exposed to 10 µM Ni from the beginning of germination. Plants were grown in water cultures, in semi-controlled conditions of a greenhouse, on ½ strength Hoagland solution to which was added Ni in the same concentration as during germination. Concentrations and distribution of Ca, Mg, K in leaf and stem were altered in the presence of increased concentration of Ni. Significant differences were found between the control and Ni-treated plants as well as among the genotypes.Neke biljke iz roda Brassica imaju sposobnost tolerancije prekomerne koncentracije teških metala, uključujući i nikal (Ni). Ispitivanje efikasnosti apsorpcije i akumulacije teških metala interesantno je sa stanovišta: 1) bezbednosti hrane, i 2) potencijala za fitoremedijaciju. Cilj ovog rada je da se ispita efekat nikla na distribuciju i akumulaciju nekih esencijalnih katjona kao što su kalcijum (Ca), magnezijum (Mg) i kalijum (K). Eksperimenti su izvedeni nad ozimom i jarom uljanom repicom (Brassica napus L.), belom slačicom (Brassica alba, L.), crnom slačicom (Brassica nigra L.) i kupusnom uljanom repicom (Brassica rapa L.). Seme je bilo izloženo uticaju 10 µM nikla (Ni) od početka klijanja. Biljke su gajene u vodenim kulturama, u polukontrolisanim uslovima u stakleniku, na ½ Hogland-ovom hranljivom rastvoru, odnosno potpunom hranljivom rastvoru u koji je dodat nikal (Ni) u istoj koncentraciji kao i tokom klijanja. Sadržaj kalcijuma (Ca), magnezijuma (Mg) i kalijuma (K) u listu i stablu izmenjen je u prisustvu povećane koncentracije nikla (Ni). Značajne razlike ustanovljene su kako između kontrole i tretmana, tako i između genotipova. Svi testirani genotipovi ispoljili su značajnu sposobnost akumulacije nikla (Ni), s tim što je Brassica napus jara forma imala najveće razlike u koncentraciji u odnosu na kontrolu (u listu 67,75 puta, a u stablu 92,5)

    Genomic evidence for genes encoding leucine-rich repeat receptors linked to resistance against the eukaryotic extra- and intracellular Brassica napus pathogens Leptosphaeria maculans and Plasmodiophora brassicae

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    © 2018 Stotz et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Genes coding for nucleotide-binding leucine-rich repeat (LRR) receptors (NLRs) control resistance against intracellular (cell-penetrating) pathogens. However, evidence for a role of genes coding for proteins with LRR domains in resistance against extracellular (apoplastic) fungal pathogens is limited. Here, the distribution of genes coding for proteins with eLRR domains but lacking kinase domains was determined for the Brassica napus genome. Predictions of signal peptide and transmembrane regions divided these genes into 184 coding for receptor-like proteins (RLPs) and 121 coding for secreted proteins (SPs). Together with previously annotated NLRs, a total of 720 LRR genes were found. Leptosphaeria maculans-induced expression during a compatible interaction with cultivar Topas differed between RLP, SP and NLR gene families; NLR genes were induced relatively late, during the necrotrophic phase of pathogen colonization. Seven RLP, one SP and two NLR genes were found in Rlm1 and Rlm3/Rlm4/Rlm7/Rlm9 loci for resistance against L. maculans on chromosome A07 of B. napus. One NLR gene at the Rlm9 locus was positively selected, as was the RLP gene on chromosome A10 with LepR3 and Rlm2 alleles conferring resistance against L. maculans races with corresponding effectors AvrLm1 and AvrLm2, respectively. Known loci for resistance against L. maculans (extracellular hemi-biotrophic fungus), Sclerotinia sclerotiorum (necrotrophic fungus) and Plasmodiophora brassicae (intracellular, obligate biotrophic protist) were examined for presence of RLPs, SPs and NLRs in these regions. Whereas loci for resistance against P. brassicae were enriched for NLRs, no such signature was observed for the other pathogens. These findings demonstrate involvement of (i) NLR genes in resistance against the intracellular pathogen P. brassicae and a putative NLR gene in Rlm9-mediated resistance against the extracellular pathogen L. maculans.Peer reviewe

    Increased regeneration efficiency of _Brassica napus_ L. cultivars Star, Westar and Cyclone from hypocotyle and cotyledonary explants

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    The comparative organogenesis of _Brassica napus_ L cultivars Cyclone, Star and Westar was studied. The cotyledonary explants gave a higher response to all the combinations of 0.5 mg/L 2,4-D and BAP (0.5, 1.0,1.5 and 2.0 mg/L} used for optimizing the conditions for callus induction. The best mean weight and mean length of callus was obtained at 0.5 mg/L 2,4-D and 1.5mg/L BAP for Star cotyledonary explants. For the complete plant regeneration the new method of exposing the explants culture to Growth regulator free medium was performed. The method was applicable to both hypocotyl and cotyledonary explants. The Shoot Induction Frequency for hypocotyl (6-34%) in the three cultivars is higher than the cotyledonary explants (3-23%). The method is speedy and almost all of the shoots and some unshooted calli (78%) form roots on the same media without prior transfer to rooting medium

    Molecular studies of Arabidopsis and Brassica with focus on resistance to Leptosphaeria maculans

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    Blackleg caused by Leptosphaeria maculans is a widespread fungal disease on B~assica napus (oilseed rape). In contrast, Arabidopsis thaliana and B. nigra are in general highly resistant. This study presents results from genomic interaction between the A. thaliana and B. napus genome with focus on L. maculans resistance. Identification and partial characterization of A. thaliana resistance in accessions, L. maculans susceptible mutants, and signaling pathways were also performed. Finally, a resistance gene to L. maculans from B. nigra was cloned and transferred to B. napus. Chromosome counts and RFLP analyses of A. thaliana DNA content in A. thaliana (+) B. napus back-crossed progeny were performed. The results showed that in BC,, originating from symmetric hybrids, the frequency of retained A. thaliana loci was reduced to 42%. The average chromosome number decreased from 48 in BC1 to 39 in BC2. These results can be compared with the asymmetric hybrid derived BC,, that had 16% loci present and an average chromosome number of 38. Clearly, symmetric hybrid offspring retained most DNA as complete chromosomes whereas asymmetric hybrid offspring contained mostly DNA fragments. Pathogen screening of the hybrid offspring revealed both cotyledon and adult leaf resistance to L. maculans. The adult leaf resistance was localized to chromosome 3 from A. thaliana, on two areas on each side of the centromere. A. thaliana resistance was examined in 171 accessions from 27 countries. Only four accessions displayed any susceptibility. To further explore the underlying causes of the resistance, a set of L. maculans disease susceptible mutants (lms) were isolated. Two of the mutants, lmsl and lms5 have been mapped to chromosome 2 and 1, respectively. The resistance was further analyzed with respect to defense signaling and effector molecules. The results indicated that resistance in A . thaliana against L . maculans depended on camalexin and is independent on salicylic acid, jasmonic acid or ethylene response. In contrast, lmsl produced wild type level of camalexin and higher expression levels than wild type of P R l , and PDFl.2. The results suggest the possibility of at least two independent resistance factors in A. thaliana. A gene conferring resistance to L. maculans, L m l , was cloned from B. nigra. Sequence analysis revealed a novel protein with two putative trans-membrane motifs and homology to the nin protein of Lotus japonicus and to A. thaliana sequences of unknown function. The knowledge gained in A. thaliana and from Lml will promote a further understanding of the mechanisms underlying resistance to L. macula

    ANALYSIS OF SLG GENE – THE MOLECULAR MARKER IN HYBRID BREEDING OF OIL SEED RAPE

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    Oil seed rape (Brassica napus L.) cultivars, donors of quality (SC) and self-incompatible (SI) lines have been analysed using identification of S-locus. In several Brassica napus cultivars one S-locus SLG gene was detected as dominant and the second S-locus as recessive. Amplification class II SLG gene screened recessive gene in all analysed samples (SC and SI). The DNA fragment of recessive gene corresponded to SLG gene W found in cv. Westar. S-haplotypes were analysed by PCR-RFLP. Different Brassica napus cultivars had an identical electrophoretic profile conforming with nonfunctional A10 allele in B. campestris. In B. napus A10 allele is localised in genome A. The functional recessive SLG gene is probably localised in genome C. Model of their segregation was suggested. SC and SI plants segregated in F2 generation at the ratio of approximately 3:1. This indicates a recessive monogenic disposition of SI in the experimental population.Autoinkompatibilita u odrůd, donorů kvality a autoinkompatibilních linií Brassica napus byla analyzována použitím identifikace S lokusu. U několika odrůd B. napus jeden S lokus genu SLG byl detekován jako dominantní a druhý S lokus jako recesivní. Amplifikací SLG genu třídy II byl odhalen recesivní gen ve všech analyzovaných vzorcích (autokompatibilních i autoinkomatibilních). DNA fragment recesivního genu sekvenčně souhlasil s SLG genem W, který byl objeven u odrůdy Westar. S haplotypy byly analyzovány metodou PCR-RFLP. Různé odrůdy B. napus měly identická elektroforetická spektra, která odpovídala nefunkční A10 alele v B. campestris. V B. napus A10 alela je lokalizována v genomu A, který pochází z B. campestris. Funkční recesivní alela SLG genu je pravděpodobně lokalizována v genomu C. Byl navržen model segregace. Autokompatibilní a autoinkompatibilní rostliny segregovaly v F2 generaci v poměru přibližně 3:1. To potvrzuje recesivní monogenní založení autoinkomaptibility v experimentálních populacích

    Host pathogen interactions in relation to management of light leaf spot disease (caused by Pyrenopeziza brassicae) on Brassica species

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    Light leaf spot, caused by Pyrenopeziza brassicae, is currently the most damaging disease problem in oilseed rape in the UK. According to recent survey data, the severity of epidemics has increased progressively across the UK, with current yield losses of up to £160M per annum in England and more severe epidemics in Scotland. Light leaf spot is a polycyclic disease with primary inoculum consisting of air-borne ascospores produced on diseased debris from the previous cropping season. Splash-dispersed conidia produced on diseased leaves are the main component of the secondary inoculum. P. brassicae is also able to infect and cause considerable yield losses on vegetable brassicas, especially Brussels sprouts. There may be spread of light leaf spot among different brassica species. Since they have a wide host range, Pyrenopeziza brassicae populations are likely to have considerable genetic diversity and there is evidence suggesting population variations between different regions, which need further study. Available disease-management tools are not sufficient to provide adequate control of the disease. There is a need to identify new sources of resistance, which can be integrated with fungicide applications to achieve sustainable management of light leaf spot. Several major resistance genes and quantitative trait loci have been identified in previous studies, but rapid improvements in the understanding of molecular mechanisms underpinning B. napus – P. brassicae interactions can be expected through exploitation of novel genetic and genomic information for brassicas and extracellular fungal pathogens.Peer reviewe
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