镉对苗期高羊茅的形态和生理影响

以20份高羊茅(Festuca arundinacea)品种为试验材料,通过测量其形态指标,运用标准差系数赋予权重法,对其进行综合评价。结果筛选出耐镉性较强的高羊茅材料M15和M8,分别采自美国的猎狗5和荷兰的巴弗斯;耐镉性较差的高羊茅材料M5和M11,分别采自荷兰的米斯特拉尔和来自日本的法恩。在此基础上,采用分光光度法,测定了这4份材料的生理指标,过氧化物酶(POD)、过氧化氢酶(CAT)、叶绿素和脯氨酸(Pro)含量的变化,进一步研究了他们的生理反应。结果表明,随着镉浓度的升高,耐镉性较强的高羊茅材料猎狗5与和巴弗斯POD和CAT含量一直呈上升趋势,而耐镉性较差的材料米斯特拉尔和法恩POD和CAT含量则呈现先升后降的趋势。随着镉浓度的升高,不同材料的叶绿素含量呈下降趋势,不同材料的脯氨酸含量则呈不断上升趋势。     

Continuous Plant Regeneration from Established Embryogenic Cell Suspension Cultures of Italian Ryegrass and Tall Fescue

The suitability of different protocols was compared for entire plant regeneration by somatic embryogenesis, of the forage plants Lolium multiflorum Lam. (Italian ryegrass) and Festuca arundinacea Schreb. (tall fescue). In the first protocol, miniature embryos were used as starting material, while mature seeds were retained in the other two. Whichever the considered protocol, undifferentiated calli were produced on Murashige and Skoog MS medium supplemented with 2,4-D. The calli were subcultured in the dark on solid MS agar medium, containing 5 mg/1 2,4-D (protocol 2) or on solid MS medium followed by transfer to a rotated liquid MS medium with 2 mg/1 2,4-D (protocol 1). In these conditions, induction of somatic embryogenesis occurred, and whole plants were regenerated during a limited lapse of time, upon transfer in the light, to MS medium supplemented with BAP but devoid of 2,4-D. The simultaneous elimination of 2,4-D and transfer to light appeared essential for full regeneration of the plants. Using this characteristic, an additional step was added to a new protocol (protocol 3) in which microcalli, cultured on liquid MS medium containing 5 mg/1 2,4-D, were transferred to the same medium with 2 mg/1 2,4-D, in the dark. In these conditions, the suspensions kept their embryogenic potential for months. In all cases, plantlets were successfully transferred into the soil. An evaluation of the somaclonal variation potential of the plants issued from each protocol is now underway.     

Evaluation of an Italian germplasm collection of Festuca arundinacea Schreb. through a multivariate analysis

Summary Forty-eight accessions of tall fescue (Festuca arundinacea Schreb.), collected from Northern to Southern Italy, were analyzed using both univariate and multivariate analysis applied to a set of 12 quantitative traits. Four principal components were found to explain 77% of the total variation in the dependence structure. Productivity characters together with heading time and dimensions of flag leaf appeared to be the major sources of diversity among tall fescue populations. On the basis of the 4 principal components similar populations were clustered according to minimal distance analysis. Seven clusters were identified. The results of cluster analysis confirmed the presence of a remarkable diversity within the germplasm collection and explained why results of a univariate analysis of variance did not reveal significant differences among groups of accessions collected in Northern, Central and Southern Italy. The multivariate approach seemed to point out a problem of genetic erosion of the local germplasm in the Po Valley (Northern Italy) and, on the whole, appeared to be a valid system for tall fescue germplasm evaluation.Research supported by C.N.R., Italy, special grant I.P.R.A., Subject 1.5.1., paper n. 1146.     

Factors influencing tissue culture responses of mature seeds and immature embryos in turf-type tall fescue

In an effort to optimize tissue culture responses of turf‐type tall fescue for genetic transformation, the effects of five culture medium supplements on tissue culture responses were investigated with immature embryos and mature seeds of an elite cultivar, ‘Coronado’, as explant tissues. For both explants, calli induced on 6‐benzylaminopurine (BAP)‐containing medium had significantly improved regeneration ability. The optimal concentration of BAP for the induction of regenerable callus from mature seeds was 0.1 mg/l. Thidiazuron also improved callus regeneration frequency of mature seeds. Casein hydrolysate, L‐proline and myo‐inositol improved callus induction of immature embryos but not mature seeds. They did not improve callus regeneration frequencies with either explant tissue. By simply slicing the mature seeds into two halves longitudinally, the callus induction frequencies, as well as the corresponding overall plant regeneration frequencies, were increased approximately three‐ to six‐fold in all three combinations of 2,4‐dichlorophenoxyacetic acid and BAP in callus induction media.     

Disturbed Mendelian segregations at isozyme marker loci in early backcrosses of Lolium multiflorum × Festuca pratensis hybrids to L. multiflorum

Summary The segregation of interspecific recombinant Festuca pratensis (Fp) alleles, introgressed into the germolasm of Lolium multiflorum (Lm), at four loci (PGI/2, AcP/2, GOT/3 and BAP) is described. Heterozygous (Lm/Fp) plants were backcrossed to L. multiflorum (2n=2×=14) and subsequent BC2 Lm/Fp sibling genotypes intercrossed.In crosses between BC1 heterozygous plants (Lm/Fp) used as males and L. multiflorum, there was a reduced transmission of the F. pratensis (Donor Parent) derived alleles in the populations with PGI/2 and AcP/2 marker loci compared to the reciprocal cross but the reduction was not significantly different in those with GOT/3 and BAP markers.Two PGI/2 marked BC2 half-sib families in particular exhibited a more extreme deficiency of Fp/Fp progeny plants than anticipated from the BC2 segregations indicating possible linkage to zygotic lethals. Deficiencies of F. pratensis alleles were, in most cases, less marked in BC2 half-sib families indicating that a further round of recombination had reduced the size of the introgressed chromosome segment or that deleterious linkages had been broken. A tendency towards heterozygote advantage was found in one BAP marked halfsib family.The significance for forage grass breeding of reduced transmission rates of Donor Parent alleles in early back-cross generations especially through the male gametes is discussed.     

高羊茅草坪不同播种量对比试验研究

为了解决高羊茅冷季型草种在武汉安全越夏的问题,进行了高羊茅草坪不同播种量对比试验,结果表明：一级质量的种子(发芽率85%以上)播种量以15～25g/m~2为宜,20g/m~2最好,有利于草坪生长及安全越夏。     

浙西地区冷季型草坪高羊茅的建植与养护技术

通过对高羊茅建植养护的多项比较试验。摸索出冷季型草坪高羊茅在浙西地区建植养护的技术要点。     

中国草芦对土壤营养吸收的效率(英文)

中国草芦(Phalaris arunainacea L.)是禾本科草芦属多年生根茎型优良禾草。对其进行N、P、K、NP、NK、PK、NPK、CK八个处理,在分蘖期采用M.K.Ka提出的公式测定中国草芦对土壤及肥料中N、P、K三元素的吸收和利用系数,并测定植物粗蛋白质和粗脂肪的含量,成熟期测定鲜草、干草产量和种子产量,结果表明:中国草芦对土壤中N的吸收系数(Kn%)以PK处理最高为12.36,K处理降低。对肥料中N的利用系数(Ky%)以NPK处理为最高(14.78),所有处理均高于对照。对土壤中P的吸收系数Kn%以NK处理最高为19.30,K处理的降低。对肥料中P的利用系数Ky%,以NP最高为19.52,所有处理均比CK高,对土壤中K的吸收系数Kn%以NP处理最高,为19.2,单一的P处理最低,对肥料中K的利用系数Ky%以NPK处理最高,为28.44。鲜草和干草产量以NP处理最高,且所有处理均高于对照。种子产量及粗蛋白质含量以NK处理最高,粗脂肪含量以NK、N处理最高,本实验说明中国草芦进行人工栽培后,施用一定比例的肥料,可以提高肥料的利用效率,提高产量的品质。     

北固山湿地野生虉草生物量的研究

对北固山湿地野生虉草的株高、茎高、叶龄、生物量等进行了研究,结果表明,虉草的株高和茎高的变化呈现出近“S”型的生长曲线,叶龄与株高和茎高均呈一元线性显著的正相关关系,生物量的变化与生育期关系密切。     

高羊茅光周期调控基因FaCONSTANS亚细胞定位与差异表达分析

构建高羊茅光周期调控基因FaCONSTANS与绿色荧光蛋白基因GFP融合的植物表达载体P-FaCONSTA NS-hGFP,基因枪转化法转入洋葱表皮细胞,荧光显微镜检测融合基因的瞬时表达.并运用实时荧光定量PCR研究光周期调控基因FaCONSTANS在长日照与短日照条件下昼夜24 h的表达差异.结果表明:FaCONST...