观赏羽衣甘蓝的离体繁殖

以花蕾为外植体，离体繁殖羽衣甘蓝８个杂各一代材料。培养基为（ｍｇ／Ｌ）：ＭＳ＋ＢＡ１－２＋ＮＡＡ０．１－０．２＋ＩＡＡ０．５＋（或不加）ＧＡ３０．３＋３％蔗糖。平均１８％－６７％的接咎花蕾产生不定芽；药有３０％的不定芽发育成完整植物。培养物的严重褐化和再生植物的普遍玻璃质化是影响植株成活的主要因素。培养基中加入活性炭和青霉素，并给以强光照射，可提高植株成活率。     

Optimal pollination conditions for seed set after a self-pollination,an intraspecific cross and an interspecific cross of marrow-stem kale (Brassica oleracea var. acephala)

Summary The effects of different pollination techniques, with and without emasculation and delayed pollination, were investigated to find the conditions for maximum seed set after self-pollination and intraspecific and interspecific crosses of Brassica oleracea var. acephala. The results indicated that the pollination conditions achieving maximum seed set vary with the type of pollination. After controlled self-pollination, the best seed set occurs in bud 3 to bud 10. For the intraspecific cross, the youngest flower and the oldest bud produced the largest number of developed ovules but bud pollination was productive to bud 8. The yields from these two pollination types were best when the female parent was not emasculated. In the interspecific cross with B. campestris cv. Marco the best results came from the youngest flowers and the oldest buds subjected to the standard practice of pollinating directly after emasculation. Possible reasons for these effects are discussed.     

Effect of cold storage and harvest date on bioactive compounds in curly kale (Brassica oleracea L. var. acephala)

In this study, curly kale stored at 1 °C for 3 and 6 weeks was compared with plants remaining in the field regarding several properties related to human health and sensory quality. Cold storage had no effect on the antioxidant capacity (ORAC assay), total phenols (Folin-Ciocalteu assay) or flavonol content, but reduced the content of vitamin C and soluble sugars. The ratio ascorbic:dehydroascorbic acid decreased from about 3 to 0.5 upon storage. The largest changes in the content of bioactive compounds were found in plants that remained in the field for 6 additional weeks, including many frost days. In these plants, the levels of flavonols, total phenols and antioxidant capacity were reduced by 25–35% and the vitamin C content by more than 50%, whereas soluble sugars and dry matter increased by roughly 20% and 30%, respectively. Among all the curly kale samples, the antioxidant capacity was positively correlated with the level of total phenols (r = 0.73, P < 0.001) and total flavonols (r = 0.70, P < 0.001). Values obtained with a non-destructive method based on chlorophyll fluorescence (ChlF) were well correlated with the flavonol content in the leaves, with the highest correlation found for quercetin (r = 0.76, P < 0.001). Using the ChlF method, the kinetics of the flavonol content during the experiment was recorded. The same method also showed gradients of flavonol content within the plant, with the highest values in the upper leaves and in the tip of the leaves. ChlF measurement, therefore, proved to be a quick and cost-effective alternative to chemical analyses of the flavonol content in curly kale.     

Competition between cultivars of fodder kale (Brassica oleracea L.) in yield trials with single-row plots

Summary Two experiments were done to evaluate the use of single-row plots for assessing digestible organic-matter (DOM) yield.In the first experiment 29 cultivars were grown in both single-row plots (unguarded) and five-row plots from which only the centre row was harvested (guarded single-row plot). The correlation between yields in the unguarded and guarded plots was very low (r=0.20). Yield was correlated (r=0.89) with cultivar height in the unguarded plots, but not in the guarded plots (r=0.19). Therefore selection for yield in unguarded single-row plots is undesirable and would favour tall kales which are prone to lodging.In the second experiment 16 cultivars were grown in single row-plots guarded by the short cultivar Maris Kestrel, the tall cultivar Vulcan and by the cultivars themselves as control. The correlations between yield in the control plots and yields in the plots guarded with Maris Kestrel and Vulcan were only moderate (r=0.56 and r=0.64 respectively). Therefore the use of a single distinct cultivar to guard single row-plots is undesirable.Selection for DOM yield should therefore be made in multiple-row plots, from which the outer rows are discarded, in order to avoid the undesirable effects of competition.     

大豆突变体ygl2黄绿叶基因的精细定位

叶片是大豆进行光合碳同化的主要器官,其颜色与光能的捕获力和转化效率有关,也与大豆的产量密切相关。因此,大豆叶色相关基因的挖掘对从光合碳同化途径解析大豆产量问题具有重要意义。黄绿叶是区别于大豆普通绿色叶片的突变类型,是研究大豆叶色相关基因的重要遗传材料。本研究发现了一个黄绿叶突变体ygl2(yellow-green leaf 2),该突变体是由大豆品系GL11自然突变而来,其黄绿叶表型可以稳定遗传。与绿叶野生型GL11相比较,突变体ygl2叶片中叶绿素含量极显著降低,株高、百粒重、蛋白含量均存在显著差异。利用GL11和ygl2构建分离群体,遗传分析表明, ygl2的黄绿叶表型受1对隐性核基因控制,利用分离群体将黄绿叶基因ygl2定位于2号染色体末端SSR标记02₁04到02₁07之间,区间物理距离为56.1 kb,包含9个基因。本研究结果为大豆黄绿叶基因图位克隆及分子标记辅助育种奠定了基础。     

The allelic relationship between A IP(internal pigmentation) and A RC (red cabbage) in Brassica oleracea var. capitata L.

Summary Internal anthocyanin pigmentation (IP), previously reported to be controlled by a single gene dominant to aa of normal green cabbage, was studied further to determine its relationship to A ^RC A ^RC of red cabbage. When IP line R52 was crossed with an early red cabbage line. F₁ heads were pigmented throughout, but pigment intensity was intermediate. Subjective classification of F₂ plants by pigmentation intensity and distribution scores gave a ratio of 1 intense red throughout (red cabbage):2 medium red throughout:1 medium to light red, restricted to the central portion of the head (IP). The genotypes A ^RC A ^RC: A ^RC A ^IP: A ^IP A ^IP. respectively, are proposed to explain these 3 phenotypic classes. F₂ progenies contained no normal green plants, supporting the conclusion that A ^IP and A ^RC are alleles.Technical Paper 7052, Oregon Agricultural Experiment Station.     

Diploids and natural autotetraploids in the predominantly vegetatively propagated Brassica oleracea L. var. ramosa DC and their cytology

Summary Perennial kale is a rare vegetable and forage crop in the Dutch province of Limburg where it is disappearing. It may be a relic of a primitive kale form which could have been grown on a large scale in West-Europe. The crop is predominantly vegetatively propagated.Cytological investigations indicated that a number of accessions are autotetraploid with 2n=4x=36. The origin and age of these autotetraploid accessions are not known, but they may stem from adventitious buds on wounded tissue during the vegetative propagation.     

羽衣甘蓝泛素结合酶ubc7基因分离、原核表达及纯化

为分离羽衣甘蓝(Brassica oleracea var. acephala)自交不亲和系(S13-bS13-b)泛素结合酶7(ubc7)基因,探讨Ubc7重组蛋白的原核表达及纯化。利用CTAB的方法提取羽衣甘蓝柱头总RNA,通过RT-PCR的方法分离ubc7基因,将编码ubc7基因的cDNA序列亚克隆到pET-14b原核表达载体中,将阳性重组表达质粒转化到大肠杆菌表达菌株BL21(DE3)pLysS中,利用IPTG进行诱导表达,并通过Ni2+-NTA树脂进行亲和层析的方法纯化重组蛋白。结果表明,获得的Boubc7含有一个长度为501 bp的开放读码框,编码一个含有166个氨基酸残基的蛋白质。预测BoUbc7的相对分子质量约为18.7 kDa,理论等电点(pI)为5.35。利用IPTG诱导的细菌蛋白中,SDS-PAGE显示出在分子量大小23 kDa处有蛋白特异性的表达,这与预测的His6融合的BoUbc7蛋白分子量相符;利用Ni2+-NTA树脂进行亲和层析纯化后,成功获得了BoUbc7融合蛋白。该试验分离了羽衣甘蓝ubc7基因,并通过原核表达系统获得了BoUbc7重组蛋白,为进一步分析其生物学功能奠定了基础。     

GBS高密度遗传连锁图谱定位甘蓝型油菜粉色花性状

甘蓝型油菜花瓣颜色是重要的观赏性状,花瓣颜色的选育和改良已成为材料创制的主要研究方向。目前对甘蓝型油菜粉色花性状定位研究未见报道。本研究以甘蓝型油菜纯系黄花62和甘蓝型油菜纯系粉花77为亲本构建双单倍体(doubled haploid,DH)群体。利用简化基因组测序技术(genotyping-by-sequencing,GBS)筛选出3253个单核苷酸多态性(single nucleotide polymorphism,SNP)标记,构建了全长1766.06 cM甘蓝型油菜连锁图谱,标记间平均遗传距离为0.54 cM;使用WinQTL Cartographer复合区间作图方法对粉色花性状进行数量性状座位(quantitative trait locus,QTL)定位,检测到位于A07和C03染色体上各1个QTL;将定位区间内基因与甘蓝和白菜同源基因进行线性比对,在这些区间中找到了一些存在于3个物种的同源基因;对粉色花定位区间内基因进行可变剪切分析发现,2个花色相关基因BnaA07g15980D和BnaA07g17500D在亲本粉色花瓣中发生内含子保留可变剪切。上述研究结果为甘蓝型油菜粉色花相关基因精细定位和分子连锁标记开发提供了更多线索。     

An improved protocol for androgenesis in cauliflowers (Brassica oleracea var. botrytis)

The genotypic responsiveness to androgenesis and the effect of two exposure times of cultured anthers to auxins (12 days and the entire period of culture) were studied in three lines of cauliflower (one spring - and two winter-types). The anthers of all genotypes responded to the protocol by producing embryos (0.2 -25.3%), 44.2% of which regenerated plantlets through organogenesis on a regulator-free B5 medium containing 40 g/l of sucrose and 800mg/l of L-glutamine. Embryo yield improvement, recently achieved on solid medium with the addition of 125mg/l silver nitrate, was not observed in liquid cultures. Mean frequencies of androgenic embryos, as affected by the duration of auxin supply to the culture, were always significantly higher (6.6- and 8.1-fold.) in the‘12 days of exposure’treatment than in the‘entire period of culture’treatment. The resolution of the parameter‘embryo percentage’into its two components (% of responsive anthers and number of embryos per responsive anther) gave evidence of a highly significant increase in the percentage of responsive anthers, whereas the number of embryos per responsive anther did not change statistically. The percentage of embryos regenerating plants was not influenced by the duration of auxin supply during anther culture. Chromosome count analysis revealed a haploid/diploid/polyploid plant ratio of 6:79:15. Of the 78 androgenic plants (RO generation) grown in the field, only 14 were fertile and produced seeds. RAPD analysis showed that none of the seven polymorphic loci out of 23 analysed expressed polymorphism within the RI progenies of 11 anther culture-derived lines.     

Light during storage prevents loss of ascorbic acid,and increases glucose and fructose levels in Chinese kale (Brassica oleracea var. alboglabra)

Chinese kale (Brassica oleracea var. alboglabra) leaves were stored at 1 °C (95% RH) under relatively low light levels (21.8 μmol m⁻² s⁻¹) or in darkness. Stomata were closed in darkness but remained open in the light. Stomatal opening was positively correlated with loss of fresh weight. Ascorbic acid levels rapidly decreased in leaves stored in darkness. The decrease was reduced to about half by storage in the light. Light resulted in higher carotenoid, glucose, fructose and starch levels. Leaves held in darkness did not turn yellow, although total chlorophyll levels slightly decreased. The levels of chlorophyll a accumulated whereas those of chlorophyll b dropped rapidly, which is consistent with the hypothesis that the first step of chlorophyll b degradation is conversion to chlorophyll a, and with the suggestion that under the present conditions chlorophyll a was not degraded rapidly. It is concluded that fluorescent light, at the level used, induced higher weight loss, whilst partially preventing the loss of vitamin C, and increasing the levels of starch, fructose and glucose.     

西兰花穴盘育苗技术研究

本试验以西兰花（Brassica oleracea L.var.italica Planch）为材料,研究了穴盘规格、基质、基肥对西兰花穴盘幼苗生长发育的影响。结果如下：不同的穴盘规格、基质和基肥对西兰花幼苗生长发育有较大的影响,实际大田生产中要培育壮苗,可以采用72孔穴盘,基质可选用轻基质（泥炭：珍珠岩：蛭石=2：1：1）,也可在轻基质中掺和一定的比例食用菌渣或园土,并拌入一定量的基肥（复合肥或缓释性肥料）。     

Mapping Co, a gene controlling the columnar phenotype of apple, with molecular markers

The columnar phenotype is a very valuable genetic resource for apple breeding because of its compact growth form determined by the dominant gene Co. Using bulked segregant analysis combined with several DNA molecular marker techniques to screen the F₁ progeny of Spur Fuji × Telamon (heterozygous for Co), 9 new DNA markers (6 RAPD, 1 AFLP and 2 SSRs) linked to the Co gene were identified. A total of 500 10-mer random primers, 56 pairs of selective AFLP primers and 8 SSR primer pairs were screened. One RAPD marker S1142₆₈₂, and the AFLP marker, E-ACT/M-CTA₃₄₆, were converted into SCAR markers designated SCAR₆₈₂ and SCAR₂₁₆, respectively. These markers will enable early selection in progenies where Co is difficult to identify. The Co gene was located between the SSR markers CH03d11 and COL on linkage group 10 of the apple genetic linkage map. Finally, a local genetic map of the region around the Co gene was constructed by linkage analysis of the nine new markers and three markers developed earlier.     

Inheritance of stalk rot resistance in cauliflower (Brassica oleracea var. Botrytis L.)

Summary The inheritance of resistance in cauliflower to stalk rot (Sclerotinia sclerotiorum (Lib.) de Bary) was investigated in population from six generations of six crosses. Disease incidence was recorded on 4 parents, 6 F^s ₁, 6 F^s ₂ and 12 back-crosses in a screenhouse under artificially created epiphytotic conditions. Resistance to stalk rot in this set of parents was found to be polygenic and under the control of recessive genes and due primarily to additive gene action. A breeding strategy emphasizing recurrent selection should lead to improvement in resistance.     

An extended random primer amplified region (ERPAR) marker linked to a dominant male sterility gene in cabbage (Brassica oleracea var. capitata)

Similar to SCAR, an extended random primer amplified region (ERPAR) marker is a PCR amplified genomic DNA fragment at a single genetically defined locus. However, ERPAR uses specific primer pairs derived from RAPD primers by adding bases sequentially to their 3′-ends. As an example, an ERPAR marker was derived from a RAPD marker (OT11₉₀₀) linked to a dominant male sterility gene in cabbage (Brassica oleracea var. capitata). After two cycles of base adding and primer pair screening, a primer pair (5′-TTCCCCGCGACT-3′and 5′-TTCCCCGCGAGA-3′) amplified a single intense band with the same size as OT11₉₀₀. The identity of the new marker and OT11₉₀₀ was verified by segregation analysis. The new marker amplified by this extended primer pair was named as EPT11₉₀₀. The development of ERPAR exploits the importance of 3′-end bases of primers in PCR ERPAR shares advantages of SCAR, but eliminates the need for cloning and sequencing. It is a fast and universal way of converting RAPD markers into stable markers. This revised version was published online in July 2006 with corrections to the Cover Date.     

Quantitative trait loci mapping of seed colour,hairy leaf,seedling anthocyanin,leaf chlorosis and days to flowering in F2 population of Brassica rapa L.

A diversity arrays technology (DArT) map was constructed to identify quantitative trait loci (QTL) affecting seed colour, hairy leaf, seedling anthocyanin, leaf chlorosis and days to flowering in Brassica rapa using a F₂ population from a cross between two parents with contrasting traits. Two genes with dominant epistatic interaction were responsible for seed colour. One major dominant gene controls the hairy leaf trait. Seedling anthocyanin was controlled by a major single dominant gene. The parents did not exhibit leaf chlorosis; however, 32% F₂ plants showed leaf chlorosis in the population. A distorted segregation was observed for days to flowering in the F₂ population. A linkage map was constructed with 376 DArT markers distributed over 12 linkage groups covering 579.7 cM. The DArT markers were assigned on different chromosomes of B. rapa using B. rapa genome sequences and DArT consensus map of B. napus. Two QTL (RSC1‐2 and RSC12‐56) located on chromosome A8 and chromosome A9 were identified for seed colour, which explained 19.4% and 18.2% of the phenotypic variation, respectively. The seed colour marker located in the ortholog to Arabidopsis thaliana Transparent Testa2 (AtTT2). Two QTL RLH6‐0 and RLH9‐16 were identified for hairy leaf, which explained 31.6% and 20.7% phenotypic variation, respectively. A single QTL (RSAn‐12‐157) on chromosome A7, which explained 12.8% of phenotypic variation was detected for seedling anthocyanin. The seedling anthocyanin marker is found within the A. thaliana Transparent Testa12 (AtTT12) ortholog. A QTL (RLC6‐04) for leaf chlorosis was identified, which explained 55.3% of phenotypic variation. QTL for hairy leaf and leaf chlorosis were located 0–4 cM apart on the same chromosome A1. A single QTL (RDF‐10‐0) for days to flowering was identified, which explained 21.4% phenotypic variation.     

Molecular mapping of black rot resistance locus Xca1bo on chromosome 3 in Indian cauliflower (Brassica oleracea var. botrytis L.)

Black rot is the most devastating disease of cauliflower worldwide causing severe damage to crop. The identification of markers linked to loci that control resistance can facilitate selection of plants for breeding programmes. In the present investigation, F₂ population derived from a cross between ‘Pusa Himjyoti’, a susceptible genotype, and ‘BR‐161’, a resistant genotype, was phenotyped by artificial inoculation using Xcc race 1. Segregation analysis of F₂ progeny indicated that a single dominant locus governed resistance to Xcc race 1 in ‘BR‐161’. Bulk segregant analysis in resistant and susceptible bulks of F₂ progeny revealed seven differentiating polymorphic markers (three RAPD, two ISSR and two SSR) of 102 markers screened. Subsequently, these markers were used to genotype the entire F₂ population, and a genetic linkage map covering 74.7 cM distance was developed. The major locus Xca1bo was mapped in 1.6‐cM interval flanked by the markers RAPD 04₈₃₃ and ISSR 11₆₃₅. The Xca1bo locus was located on chromosome 3. The linked markers will be useful for marker‐assisted resistance breeding in cauliflower.