Shortening the generation cycle in faba bean (Vicia faba) by application of cytokinin and cold stress to assist speed breeding

The aim of this study was to reduce the length of the breeding cycle for faba bean by accelerating seed setting. We examined the mode and time of exogenous 6-benzylaminopurine (BAP) (cytokinin) application, and cold treatments and their combinations in two faba bean genotypes. Acropetal node number of pod and seed set and pollen viability were recorded during the experiments. Application of BAP improved pollen germination. The application of 10^–5 M BAP 4 days after flowering increased seed set at the lower nodes. Cold treatment (8/4°C day/night for 2 days) after the onset of flowering induced the formation of more pods and faster pod set compared to the non-cold treatment. The time to first seed was significantly reduced, and pollen viability was increased in plants exposed to cold treatment. Increased pollen viability also showed a significant positive correlation with seed setting. The combinations of 10^–5 BAP and cold treatment together had similar and independent effects. These results will accelerate plant breeding in faba bean by providing additional tools for reducing generation time.     

魏可葡萄气生根发育的转录组分析

葡萄气生根是在高温高湿环境下老蔓上发育形成的一种特殊根系类型,发育程度较低,具有分化潜力。通过技术手段诱导魏可葡萄当年生结果枝茎节处萌发气生根,以同一结果母枝未处理茎节为对照进行根系转录基因表达情况分析,结果表明,诱导气生根发育过程中有3 989个基因表达量上升,2 830个基因表达量下调。采用GO功能分类,可将注释的基因划分为40个功能类别,包括催化活性、结合和代谢过程等。部分根系关键基因表达结果表明,生长素、赤霉素、脱落酸在内的所有植物激素都参与了调控过程,结合生长素下游相应基因分析,内切葡聚糖酶基因、PRE基因和高亲和力硝酸盐转运体基因在气生根发育过程中显著上调表达,表明降解茎节处表皮细胞壁、利用硝酸盐在茎节处富集刺激根芽萌发是气生根生长发育调控机理之一。     

水稻蜡质稀少突变体wax1的鉴定及基因定位

【目的】 蜡质是植物表面的一种重要保护物质,筛选和鉴定水稻蜡质相关突变体有助于解析水稻蜡质形成的遗传机制。【方法】利用EMS诱变籼稻品种湘早籼6号,从突变体库中筛选出一个蜡质稀少的突变体wax1,考查突变体的形态特征和农艺性状,利用突变体与02428杂交的F₂群体定位目标基因,并通过荧光定量PCR分析相关基因的表达情况。【结果】与野生型相比,wax1突变体具有叶片短小皱褶、叶表面蜡质晶体减少、穗长变短等形态特征;在农艺性状方面,突变体的株高、每穗总粒数和千粒重显著降低,但有效穗数显著高于野生型;遗传分析表明,wax1的突变表型受一对隐性核基因控制,将WAX1基因定位在第10染色体上SSR标记RM5806与InDel标记P1之间,物理距离约为49.8 kb;定位区间内的测序结果表明,突变体中β-酮脂酰-CoA合酶的编码基因发生单碱基突变,导致催化活性中心的一个氨基酸发生改变。WAX1基因的突变显著提高了同源异型盒基因OSH6的表达,同时引起部分IAA基因的差异表达。【结论】WAX1基因突变引起叶表面蜡质晶体的减少,同时通过影响茎尖分生组织和生长素的信号转导引起植株生长发育等多方面的异常。     

Micropropagation of Prunus scoparia,a Suitable Rootstock for Almond under Drought Conditions

Prunus scoparia is a wild deciduous shrub, usually living on dry calcareous soils of the rocky mountains and has been used as a grafting rootstock for domesticated almonds to provide drought resistance. In the current study, micropropagation ability of P. scoparia was investigated using cytokinin and auxin. Uniform nodal shoot pieces (3–5 cm in length) of seedlings were used as explants. The explants were disinfected with 10% sodium hypochlorite solution. For adventitious shoot induction and proliferation, Murashige and Skoog (MS) media containing 7.00 g/l agar and 30.00 g/l sucrose containing five concentrations of benzyl adenine (BA) (0.00, 0.50, 1.00, 2.00, and 4.00 mg/1) and also containing six concentrations of Thidiazuron (TDZ) (0.00, 0.50, 1.00, 2.00, 5.00, and 7.00 mg/1) were compared. For rooting, in vitro shoots (2–3 cm) were transferred into ½ MS medium supplemented with 30 g/l sucrose, 7.50 g/l agar, and different concentrations of IBA (0.00, 0.25, 0.50, and 1.00 mg/l) and NAA (0.00, 0.25, 0.50, and 1.00 mg/l). Based on the results obtained for shoot proliferation, only 2.00 and 4.00 mg/l BA and 2.00 mg/l TDZ concentrations generated shoots, while other treatments did not show shoot proliferation. Among the three treatments that generated shoots, the best results for shoot number, leaf number, and leaf color quality were observed in media containing 2.00 mg/l TDZ. Based on the results obtained for rooting, the effect of IBA concentrations on the rooting percentage, root number, and root length was significant. Among IBA concentrations, only 0.50 mg/l IBA induced rooting, while there was no rooting in the media containing other IBA concentrations. None of the NAA concentrations showed rooting. In conclusion, MS culture medium supplemented with 2.00 mg/l TDZ and ½ MS culture medium supplemented with 0.50 mg/l IBA are suggested for in vitro shoot proliferation and rooting of P. scoparia, respectively. The results presented herein could be used for in vitro selection and micropropagation of P. scoparia.     

几种作用因子对多年生黑麦草组织培养影响的研究

以多年生黑麦草成熟种子为外植体进行了愈伤组织诱导和分化的研究。结果表明:dicamba替代2,4 D,蔗糖替代麦芽糖可以显著提高愈伤组织诱导率和植株再生率;在一定的浓度范围内(3～9mg·L-12,4 D)2,4 D浓度的升高可明显提高愈伤组织的诱导率,但同时却降低了分化率;在愈伤诱导培养基中同时使用两种生长激素(2,4 D和NAA)的效果要好于单独使用一种生长激素(2,4 D)的效果;水解酪蛋白、脯氨酸和谷氨酰胺浓度的增加并没有促进植株再生率的升高。     

植物生长调节剂在花期调控中的应用

利用人为的因素可控制花卉在自然花期之外开放,统称为花期调控。笔者主要综述了植物成花机理以及赤霉素等植物生长调节剂在花期调控中的机理和应用,以期对花期调控的应用起到借鉴作用。     

甜椒组培育苗技术

研究了甜椒组培育苗技术,结果表明MS＋BA0．6mg／L＋IAA0．1mg／L配方接种,甜椒不定芽增殖系数达6．0,并且芽生长健壮;1／2MS＋NAA0．1mg／L配方的生根效果最好,15d生根率达71．9％,20d后生根率达100％。根系生长发达。     

植物TIR1/AFBs基因家族研究进展

TIR1/AFBs基因家族是一种存在于细胞核中的生长素受体,属于F-box蛋白基因中的一个小亚族。它们通过与相关生长素相结合活化转录因子来促进基因的表达,从而进行调控,是生长素信号转导过程中的关键部分。为了深入研究生长素信号转导机制,从TIR1/AFBs基因家族的发现与结构,家族成员表达模式的差异及对植物生长发育方面的调节等方面概括介绍了TIR1/AFBs基因家族的分子调控机制,总结了TIR1/AFBs基因的功能。最后探讨了TIR1/AFBs基因的研究方向。     

Callus Induction of Aloe vera L var chinensis (Haw) Berg

Studies were given to the induction and growth of callus of Aloe vera L.var.chinensis(Haw.) Berg when the young stem was applied as explant.MS was taken as basic medium,added with various concentrations of auxins(IAA,IBA,NAA and 2,4-D),cytokinins(6-BA,KT and Zeatin) and the different combinations of these plant growth regulators.Results showed that the callus is barely induced by cytokinin alone,and the callus induction rates have significant difference when different concentrations of auxin and different combinations of auxin with cytokinin are used on the MS medium.In order to inhibit callus browning during culturing,various concentrations of vitamin C or active carbon are added into four combinations of auxin and cytokinin respectively,which can induce callus most effectively.The result showsd that vitamin C can alleviate callus browning more effectively than the active carbon.The most efficient medium for induction and growth of callus of Aloe vera L.var.chinensis(Haw.) Berg was MS+2.0 mg/L 6-BA+0.5 mg/L 2,4-D+10 mg/ L vitamin C,with which the callus induction rate can reach to 91.4% and callus grow vigorously.