Transformation of rapid cycling cabbage (Brassica oleracea var. capitata) with Agrobacterium rhizogenes

Summary Genetically transformed cabbage (Brassica oleracea var. capitata) roots were obtained after inoculation with two engineered Agrobacterium rhizogenes strains, each harbouring a plant selectable marker gene in their T-DNA. Axenic root clones resistant to kanamycin or hygromycin B were established, most of which did not exhibit the phenotypic characteristics of Ri-transformed roots. Shoot regeneration was induced from roots after treatment with 2,4-dichlorophenoxyacetic acid (2,4-D). The resulting plants exhibited various phenotypes: some looked normal, while others showed the transformed phenotype observed in other species. Direct evidence for genetic transformation was obtained by molecular hybridization. The trait was transmitted to the progeny. Transformed cabbage plants can be obtained within 6 months using this approach.     

大气CO2与吡虫啉对甘蓝土壤细菌与微生物生物量C的影响

采用田间开顶式CO2控制气室(OTC),研究了375μL/L、750μL/L两个CO2浓度和CK、LC50、LC903种吡虫啉浓度处理条件下,甘蓝根际土壤细菌与非根际土壤微生物生物量C的变化。750μL/L CO2处理对甘蓝根际细菌数量显著增加(P0.01),而在同一CO2水平下各农药处理间并无显著差异;根区土壤微生物生物量C只有在750μL/L CO2且无吡虫啉处理的条件下显著(P0.05)下降,在LC50、LC90处理的影响下并不显著。同一CO2水平下,根区土壤微生物生物量C受农药处理的影响不明显。     

A decimal code describing the developmental stages of head cabbage (Brassica oleracea var. capitata)

The developmental stages of head cabbage (Brassica oleracea var. capitata) as a vegetable have been characterised by a decimal code. Five primary stages are recognised: germination, emergence and establishment, leaf formation, head formation and maturity. Each primary stage is divided into secondary stages, which apply both to single plants and to crops. Maturity is defined as the head having obtained a marketable weight and density. The standing ability is defined as the number of days from 90% of the crop being marketable to 25% of the crop having become unmarketable.     

Effects of intraspecific variation in white cabbage (Brassica oleracea var. capitata) on soil organisms

Intraspecific variation in plants can affect soil organisms. However, little is known about whether the magnitude of the effect depends on the degree of interaction with the roots. We analyzed effects of plant intraspecific variation on root herbivores and other soil organisms that interact directly with living plant roots, as well as on decomposer organisms that interact more indirectly with roots. We used four different white cabbage (Brassica oleracea var. capitata) cultivars exhibiting a high degree of intraspecific variation in root glucosinolate profiles. Intraspecific variation affected root-feeding nematodes, whereas decomposer organisms such as earthworms and Collembola were not affected. Root-feeding nematodes were most abundant in one of the cultivars, Badger Shipper, which lacked the glucosinolate gluconasturtiin. The effect of the intraspecific variation in glucosinolate composition may have been restricted to root-feeding nematodes due to the rapid degradation of glucosinolates and their breakdown products in the soil. Additionally, the low biomass of root-feeding nematodes, relative to other soil organisms, limits the possibility to affect higher trophic level organisms. Our results show that variation in root chemistry predominantly affects belowground herbivores and that these effects do not extend into the soil food web.     

Functional properties of a chitinase promoter from cabbage （Brassica oleracea var.capitata）

The 5‘-region of the chitinase gene cabch29,derived from Brassica oleracea var.capitata,has been sequenced and analyzed for cis-acting elements important in controlling gene expression in transgenic tobacco plants.Different 5‘-deletion fragments were linked to reporter gene β-glucuronidase (GUS) as translational fusions,and the expression of these chimeric genes was analyzed in vegetative organs and tissues.Sequences up to-651 showed some basal GUS activity with nearly equal levels in wounded and intact tissues.The addition of further upstream sequences(-651 to-1284) enhanced expression level,and the expression driven by this fragment was inducible by a factor of two to three-fold by wounding.Histochemical analysis of different tissue from transgenic plants that contain cabch29 promoter-gus fusion gene demonstrated woundinducible and tissue-specific cabch29 promoter activity in plants containing the 1308 base pair fragment.The location of GUS activity appears to be cell-specific,being highest in vascular cells and epidermal cells of stem,leaf and roots.Meanwhile,the temporal and spatial expression of cabch29-GUS fusion gene has been investigated.Among the different vegetative organs,a high level of GUS activity was observed in stem and a moderate one in roots;whereas,wounding stress led to a high level of GUS in stem and moderate one in leaf.     

Stimulation of androgenesis in white cabbage (Brassica oleracea var. capitata) anthers by low temperature and anther dissection

Anther culture was performed on two local cultivars, Ljubljansko and Varadinsko, and the F₁ cv. Krautman (Bejo-Zaden). The effects on androgenesis of hot and cold temperature treatments and different dissections of anthers were evaluated. In contrast to cv. Krautman, cvs. Ljubljansko and Varadinsko produced more embryos after cold pretreatment of flower buds (4°C, 48 h) than after standard treatment (35°C, 24h). Simultaneous cutting of the anther tip and removal of the filament gave the best results in comparison to other tested dissections. Microscopical observations of sectioned anthers revealed enhanced embryo development near the cut ends of the anthers. Ploidy analysis revealed the presence of haploids among embryos resulting from cold treatment (4°C, 48 h), treatment at elevated temperature (35°C, 24 h), and among embryos resulting from dissections of anther tips.     

Agrobacterium tumefaciens-mediated transformation of broccoli (Brassica oleracea var. italica) and cabbage (B. oleracea var. capitata)

Transgenic broccoli (Brassica oleracea var. italica) was produced by two Agrobacterium tumefaciens-mediated transformation methods. One used flowering stalk explants from mature plants; the other used hypocotyl and petiole explants from in vitro-grown seedlings. Several hundred transformants containing a Bacillus thuringiensis -endotoxin gene (CryIA(c)-type) and the neomycin phosphotransferase gene were recovered. Rooted transformants were obtained in as little as 3 months using seedling explants. Transgenic cabbage was also obtained by the seedling explant method. Parameters important for high efficiency regeneration and transformation rates included use of a tobacco nurse cell layer, sealing of petri dishes with a porous surgical tape instead of Parafilm, preculture of seedling explants and appropriate length of co-cultivation with Agrobacterium. Advantages and disadvantages of each transformation procedure are discussed.     

Recurrent somatic embryogenesis and plant regeneration from immature zygotic embryos of cabbage (Brassica oleracea var. capitata) and cauliflower (Brassica oleracea var. botrytis)

A simple and rapid protocol was established for repetitive somatic embryogenesis and subsequent plant regeneration in two important Brassica oleracea varieties, cabbage and cauliflower. Direct regeneration of somatic embryos (SEs) was achieved from immature zygotic embryos cultured on B5 plant growth regulator (PGR)-free (B5-0) induction medium and on B5 medium supplemented with 1 mg l^?1 2,4-dichlorophenoxyacetic acid (2,4-D) (B5-D). Zygotic embryos of both cabbage and cauliflower at the cotyledonary (C) stage (1.8 mm long) incubated on B5-0 medium displayed the highest embryo-forming capacities (EFCs) of 11.84 and 11.95, respectively. Secondary somatic embryos (SSEs) appeared on the cabbage and cauliflower’s primary embryos at a high frequency (83.3 and 87.5 %, respectively), and this process continued in a repetitive way on PGR-free Murashige and Skoog (MS-0) medium. The embryogenic potential of the cultures with a gradual diminution was maintained for 10 months (ten cycles). A total of 20 % of the mature SSEs from cabbage and 55 % from cauliflower spontaneously regenerated plantlets on MS-0 medium. The addition of 1 mg l^?1 6-benzyladenine (BA) or 6-furfurylaminopurine (Kin) in the regeneration medium significantly improved somatic embryo conversion into plantlets by up to 56 % in cabbage and 79 % in cauliflower. Regenerated plants acclimated successfully to ex vitro conditions and displayed morphological and reproductive characteristics similar to seed-derived plants. Effective recurrent somatic embryogenesis may be an appropriate practical solution for clonal propagation and genetic modifications of cabbage and cauliflower.     

Evaluation of Paenibacillus spp. isolates for the biological control of black rot in Brassica oleracea var. capitata (cabbage)

The ability of isolates of Paenibacillus spp. to protect Brassica oleracea var. capitata (cabbage) against the black rot pathogen, Xanthomonas campestris pv. campestris (Xcc),was evaluated. Twenty-four isolates of Paenibacillus spp., isolated from New Zealand-grown brassica hosts or soil, were evaluated for in vitro antagonism towards six Xcc isolates. Seven Paenibacillus spp. isolates with different levels of in vitro suppressive activity against Xcc were screened in pot experiments for their capacity to reduce black rot symptoms on cabbage. Two Paenibacillus isolates (P10 and P16) exhibited biocontrol activity against Xcc, and four isolates (P1, P6, P9, and P24) reduced cabbage seed germination and seedling emergence. The dependence of bioactivity on inoculum rate was investigated with three Paenibacillus isolates (P6, P10, and P16) at three different concentrations (5?×?10⁸, 5?×?10⁹, and 5?×?10¹⁰?CFU?ml^?1). Negative effects on seedling emergence were detected with isolate P6 at concentrations?≥5?×?10⁹?CFU?ml^?1. All three isolates applied at the three concentrations reduced black rot symptoms on the cotyledons and true leaves. There was poor or no relationship between the inhibitory effect of Paenibacillus spp. isolates on the growth of Xcc in vitro, and their biocontrol activity in vivo. Paenibacillus isolate P16 was identified as a potential biological control of black rot in cabbage.     

Sampling a weighted pest complex: caterpillars in North Korean cabbage (Brassica oleracea var. capitata) crops

The lepidopteran pests Plutella xylostella L. (Plutellidae) and Pieris rapae L. (Pieridae: Pierini) are responsible for major yield losses of cabbage, Brassica oleracea L. (Brassicaceae), in North Korea. Preliminary integrated pest management (IPM) programmes using economic thresholds (ETs) to schedule insecticide applications have proved promising and have demonstrated marked increases in yield compared to standard farming practice, which relies heavily on synthetic insecticides. To use ETs effectively on a routine basis, farmers need efficient yet sufficiently precise methods of surveying crops for pests. Here we construct and validate binomial sequential sampling plans for the two-species pest complex and for P. rapae alone. The recommended plans would be practical to implement, demanding maximum sample sizes below 50 plants, and proved very slightly conservative with respect to classifying the population relative to the ET (i.e., they were slightly more likely to suggest control at the ET than not).     

Assessing three methods for identification of desirable genotypes in white cabbage (Brassica oleracea L. var. capitata)

Summary A desirable genotype is a genotype performing well in a chosen set of environments. Three methods for identification of desirable genotypes were assessed in two cabbage data sets: regression analysis, multidimensional scaling of dissimilarity matrices, and biplot of deviation matrices. Using the regression approach is not recommended mainly for two reasons: (1) it is difficult to identify the desirable genotypes since one has to unify three parameters into one decision; (2) the regression method failed to identify the most desirable genotypes in one of the data sets. Multidimensional scaling and the biplot method were in accordance with each other and with the mean tables when different subsets where compared. Consequently, they were considered more adequate for identifying desirable genotypes. In cases where rank 2 approximation of the analysed matrix was justified, the biplot revealed more information in one display and was, therefore, considered particularly useful in plant breeding for larger target areas.     

结球甘蓝和青花菜小孢子胚植株再生

结球甘蓝(Brassica oleracea var. capitata)和青花菜(Brassica oleracea var. italica)小孢子胚再生植株频率低是目前影响游离小孢子培养技术有效应用的关键问题之一, 研究其小孢子胚植株再生频率的影响因素, 提高胚再生植株频率, 对促进游离小孢子培养技术在甘蓝类蔬菜育种中更好地应用具有重要意义。该文以结球甘蓝中甘11和青花菜TI-111等基因型为试材, 对影响游离小孢子胚再生成植株的固体培养基类型、琼脂浓度、胚的类型及胚在液体培养基中的滞留时间等因素进行了研究。结果表明: 游离小孢子培养25天的子叶胚在琼脂浓度为1%–1.25%的B5培养基上植株再生频率最高。进一步通过8个不同基因型对上述实验结果进行了验证, 结果显示, 游离小孢子培养25天的子叶胚在1%琼脂浓度的B5培养基上植株再生频率达77.8%–97.2%。     

Molecular cloning and functional expression of a phospholipase D from cabbage (Brassica oleracea var. capitata)

We cloned and expressed a full-length cDNA encoding a phospholipase D of type alpha (PLDalpha) from cabbage. Analysis of the cDNA predicted an 812-amino-acid protein of 92.0 kDa. The deduced amino acid sequence of cabbage PLD has 83% and 80% identity with Arabidopsis PLDalpha and castor bean PLD, respectively. Expression of this cDNA clone in E. coli shows a functional PLD activity similar to that of the natural PLD.     

结球甘蓝和青花菜小孢子胚植株再生

结球甘蓝（Brassica oleracea var.capitata）和青花菜（Brassica oleracea var.italica）小孢子胚再生植株频率低是目前影响游离小孢子培养技术有效应用的关键问题之一,研究其小孢子胚植株再生频率的影响因素,提高胚再生植株频率,对促进游离小孢子培养技术在甘蓝类蔬菜育种中更好地应用具有重要意义。该文以结球甘蓝中甘11和青花菜TI-111等基因型为试材,对影响游离小孢子胚再生成植株的固体培养基类型、琼脂浓度、胚的类型及胚在液体培养基中的滞留时间等因素进行了研究。结果表明：游离小孢子培养25天的子叶胚在琼脂浓度为1%–1.25%的B5培养基上植株再生频率最高。进一步通过8个不同基因型对上述实验结果进行了验证,结果显示,游离小孢子培养25天的子叶胚在1%琼脂浓度的B5培养基上植株再生频率达77.8%–97.2%。     

Frequency of polyvalents in relation to fertility of autogamized autotetraploid kohlrabi (Brassica oleracea var.gongylodes L.), cabbage (Brassica oleracea var.capitata L.) and their hybrids

The present work is a study of the frequency of polyvalents in autotetraploid kohlrabi, cabbage and their intervarietal hybrids. Polyvalents were stated in the final phases of heterotypic prophasis, usually in diakinesis. In none of both varieties any significant relationship between frequency of polyvalents and fertility expressed by mean number of seeds per siliqua was found, while in intervarietal hybrids some correlation was observed between mentioned characters. This leads to the conclusion that the frequency of polyvalents is not always a measure of the degree of fertility in auto-polyploids. Autotetraploid intervarietal hybrids were characterized by marked prelevance of bivalents, by a considerable percentage of well-developed pollen grains and by high correlation between frequency of polyvalents and fertility. These characters are typical rather for amphidiploids.     

In vitro Propagation of Red Cabbage (Brassica oleracea L. var. capitata)

By manipulation of various growth regulators and physical conditions,plants have been regenerated from excised roots, stem segments,cotyledons, leaves, and callus cultures of red cabbage (Brassicaoleracea var. capitata) grown under in vitro conditions. Shootbuds were induced on isolated root segments (1 cm long) culturedon Murashige and Skoog's medium and the frequency of bud formationwas greatly enhanced by the addition of kinetin (0.5 part 10^–6).Callus obtained from the seeds, cotyledons, and hypocotyl segmentscultured on a medium fortified with 2,4-D (1 part 10^–6),kinetin (0.1 part 10^–6), and coconut milk (10%, v/v) hasbeen repeatedly subcultured. The callus is slow growing, andon transference to a kinetin (2 parts 10^–6) and IAA (2parts 10^–6) medium underwent morphogenesis to give riseto plants. The significance of the propagation of red cabbageby in vitro culture is pointed out.     

Chloroplast and mitochondrial SSR help to distinguish allo-cytoplasmic male sterile types in cabbage (Brassica oleracea L. var. capitata)

The profiles of single sequence repeat (SSR) in six distinct allo-cytoplasmic male sterile (CMS) types of cabbage (Brassica oleracea L. var. capitata) were generated using 32 SSR primer pairs derived from the Arabidopsis thaliana chloroplast (cp) genome and another 21 SSR primers from the B. napus mitochondrial (mt) genome sequences. In total, 11 cpSSR and 4 mtSSR primers revealed polymorphism among the six cabbage CMS types, namely NigCMS, OguCMSR₁, OguCMSR₂, OguCMSR₃, OguCMSHY and PolCMS. Through cluster analysis, six cabbage CMS types could be unambiguously differentiated with just three sets of primers (ACP43, ACP47, mtSSR2). Analysis of the selected amplicon sequences showed high identity to that of the corresponding sequences in A. thaliana, B. rapa and B. napus. The aligned cluster analysis revealed that the polymorphism mainly included SSR number variation, single nucleotide polymorphism (SNP), and sequence insertion or deletion (InDel). Our results demonstrated that specific mitochondrial or chloroplast SSR analysis could be a feasible alternative means for cabbage CMS type identification.     

RAPD analysis of seed purity in a commercial hybrid cabbage (Brassica oleracea var. capitata) cultivar.

The use of random amplified polymorphic DNA (RAPD) markers for evaluating seed purity in a commercial F1-hybrid cabbage (Brassica oleracea var. capitata) cultivar is demonstrated. Genomic DNA isolated from single ungerminated seed was found to be suitable for RAPD analysis. DNA from F1-hybrid and its parental lines was subjected to RAPD screening with 36 random decamer arbitrary primers. A total of 241 scorable products were observed with 54 (22%) being polymorphic. The RAPD data showed that the parental lines of this commercial cabbage cultivar were not very closely related. Two primers were chosen for purity testing of the F1-hybrid seeds. The sib (inbred seed; seed from self-pollination of parental lines) contamination results obtained by RAPD analysis were comparable to the commonly used grow-out trial and isozyme analysis, hence showing that RAPD analysis can be used for seed purity testing of commercial hybrid cabbage seeds.     

结球甘蓝游离小孢子胚胎发生

以结球甘蓝品种“强夏”为材料进行游离小孢子培养,对与胚胎发生关系密切的因子进行探讨。研究结果表明,在盛花前期取材最适宜;单核晚期至双核期的小孢子才能发育成胚状体;含17%蔗糖的培养液在培养初期有利于小孢子存活;培养3d后胚胎诱导则以14％蔗糖浓度为最好;高浓度（17％）蔗糖培养3d后添加低浓度（11％）蔗糖培养液能大大提高胚胎发生能力,比一直在14％蔗糖培养液培养的提高282．4％,比更新培养液培养的提高126．1％。     

结球甘蓝耐裂球研究进展

综述了国内外结球甘蓝裂球性状及鉴定方法的研究进展,从裂球的遗传因素、叶片解剖特征、生理生化特性等方面分析了结球甘蓝裂球发生的原因,并提出了防治裂球的栽培措施.