大白菜-结球甘蓝4号单体异附加系的鉴定

大白菜-结球甘蓝异附加系是利用结球甘蓝的优良基因对大白菜进行品种改良的中间材料,在遗传理论研究和育种实践中均具有重要应用价值。本研究以大白菜-结球甘蓝异源三倍体（AAC, 2n=29）与二倍体大白菜（AA,2n=20）回交一代的自交后代为材料,经过细胞学鉴定,从中筛选出大白菜-结球甘蓝4号单体异附加系,对其减数分裂和植株性状进行了观察与调查。该异附加系的获得为研究芸薹属A、C基因组的亲缘关系,以及向大白菜中导入结球甘蓝的优良基因,扩大种质遗传背景提供了基础材料。     

秋水仙素诱导党参四倍体?

以党参（Codonopsis pilosula (Franch.) Nannf.）为诱变材料,用改良秋水仙素涂抹法进行多倍体诱变以获取四倍体,研究了秋水仙素对党参的诱导效果以及变异株的形态学与细胞学变化。本试验利用0.2%秋水仙素琼脂凝胶处理党参幼苗获得了四倍体材料,结果表明党参经秋水仙素诱导后,以处理24h加倍率最高,为34.14%。四倍体植株形态学变异表现为苗期生长受阻,叶片变大变厚,叶形指数变小;花器变大,茎杆加粗,茎节变短;结实率下降而千粒重增加等。党参四倍体植株的细胞学表现为叶下表皮气孔器变大,气孔密度下降,保卫细胞内叶绿体的含量增加;花粉粒变大而花粉育性降低;根尖细胞有丝分裂染色体数目为2n=4x=32,其对照为2n=2x=16。四倍体党参减数分裂染色体行为复杂,同源染色体出现了多种联会方式。     

利用氟乐灵进行同源四倍体萝卜种质创制研究

本研究应用除草剂氟乐灵处理两叶一心幼苗生长点,进行同源四倍体萝卜种质诱导,对变异植株进行形态、细胞学鉴定和花粉母细胞染色体数目鉴定.结果表明,应用0.2 mmol/L和1.0 mmol/L氟乐灵处理,6个萝卜品种都获得同源四倍体植株,10 mmol/L处理仅在Nau-zhqh得到同源四倍体;其中0.2 mmol/L处理Nau-dy和1.0 mmol/L处理Nau-xbch获得四倍体最高诱导率（40%）;四倍体种质与二倍体种质相比,形态性状、气孔大小、保卫细胞内叶绿体数目、花器官大小、花粉粒大小及花粉萌发率都存在显著差异,将形态、气孔鉴定和染色体计数结合可以准确确定变异株的倍性.研究表明利用氟乐灵诱导是进行萝卜同源四倍体种质创新的有效途径之一.     

秋水仙素诱导青岛百合四倍体研究

以青岛百合试管苗为试验材料,采用浸泡法和混培法研究了秋水仙素对青岛百合进行染色体加倍的诱导效果。结果表明:以0.05 %的秋水仙素浸泡处理24h的诱导效果最佳,诱导频率高达53.3%;经秋水仙素诱导的多倍体与正常二倍体植株比较,植株叶片变大,根系粗壮,气孔显著增大而单位面积气孔数减少。对变异材料的细胞学研究发现, 四倍体植株的染色体数目为2n=4x=48。     

秋水仙素与DMSO诱导豌豆同源四倍体

为获得同源四倍体豌豆,用0.05%秋水仙素（C22H25O6）和2%二甲基亚砜（DMSO）混合水溶液处理豌豆种子,分为24、48、72h三个不同处理时间与5℃～6℃、10℃～12℃、15℃～16℃、18℃～20℃、30℃ 5个不同培养温度。试验结果表明,培养温度为15 ℃～16℃时,用0.05%秋水仙素和2%DMSO混合水溶液间歇处理宝峰2号豌豆种子48h,植株成活率和诱导率均最高,分别为54.5%和9.5%。对处理后代进行形态学和细胞学观察比较,发现可育的多倍体染色体数目2n=4x=28,为同源四倍体。该同源四倍体与其二倍体在植株形态上的显著差异表现在：植株高大,茎和卷须变粗,单株总叶面积变大,叶色更绿,开花期延迟,花粉粒和花粉母细胞变大,荚大,自交结实,粒大。试验显示获得的同源四倍体对育性有效。     

秋水仙素诱导甘菊多倍体研究

以甘菊种子为试验材料,研究了不同秋水仙素浓度和处理时间对甘菊多倍体诱导的影响。结果表明:500mg/L的秋水仙素水溶液浸渍种子12h,变异率为23%,达到了极显著差异。根尖染色体压片检查表明,四倍体染色体数为2n=4x=36,并且获得了同源四倍体甘菊1株(2n=4x=36)。四倍体植株表现出叶片下表皮气孔保卫细胞变大,叶绿体数变多,叶片变小,花径变大,舌状花数目减少,管状花数目增多。     

秋水仙碱诱导栝楼四倍体

采用改良L.D.Cua法诱导短把栝楼获得四倍体,研究了0.2%浓度的秋水仙碱诱导短把栝楼染色体倍性变异的最佳处理时间、四倍体栝楼与原栝楼的形态特征及其四倍体与二倍体的细胞学鉴定。结果表明：0.2%秋水仙素的最佳处理时间为72 h,诱变率达82.1%。与二倍体相比,四倍体表现为：生长变缓;叶片增大、皱缩和变厚、叶形指数减小;叶片保卫细胞增大,气孔密度降低,叶绿体数目增加,叶色加深。根尖压片表明：二倍体的染色体数目为2n=66,大部分四倍体植株的染色体数目为2n=132,M2代部分四倍体植株也存在嵌合现象。     

大叶铁线莲四倍体的诱导及初步鉴定

以毛茛科铁线莲属植物大叶铁线莲为试验材料,采用初生分生组织处理法用0.2%秋水仙碱溶胶诱导大叶铁线莲顶芽以期获得多倍体。本研究探讨了秋水仙碱诱导大叶铁线莲的最佳处理时间,并对所得的诱变株进行形态学和细胞遗传学鉴定。结果表明:0.2%秋水仙碱诱导多倍体最佳时间为48h,诱导率可高达80%。形态学方面,所得变异株与对照株叶片相比,叶片加长、加宽、增厚,叶形指数变小。变异株的叶片下表皮气孔明显大于对照,而气孔密度明显小于对照;保卫细胞中的叶绿体数目明显高于其二倍体对照;SPAD值表明叶绿素含量也有明显增加。根尖有丝分裂细胞学鉴定结果表明:对照株的染色体数目均为16(2n=2x),而变异株的染色体数为32(2n=4x),由此表明本研究通过秋水仙碱诱导大叶铁线莲成功获得四倍体。     

矮化型八倍体小偃麦的选育

矮化型八倍体小偃麦“TAI7044”是以天蓝偃麦草(Agropyron glaucum)作父本，春小麦品种“晋春7号”作母本杂交，并采用冬小麦品种“21124”回交克服其属间杂种的不育性，经过连续9年选育而成。细胞学观察结果表明，它的体细胞染色体数目2n=56的植株占77.3%，花粉母细胞减数分裂中期Ⅰ2n=28Ⅱ的细胞占59.95%，其染色体构型为1.43 Ⅰ+27.48Ⅱ+0.09Ⅲ+0.04Ⅳ。同工酶电泳结果表明，它的酯酶比双亲(普通小麦和天蓝偃麦草)多出5条新生酶带，同时又缺少双亲分别具有的3条酶带,进一步证明了利用外源种质与小麦遗传背景之间相互作用产生新性状的可能性。     

二甲戊灵与秋水仙素离体诱导虎眼万年青多倍体发生的比较研究

以白花虎眼万年青(Ornithogalum thyrsoides)组培的丛生芽(2n=2x=12)为试验材料,采用溶液浸泡法,研究秋水仙素和二甲戊灵的不同浓度和处理时间对白花虎眼万年青多倍体的诱导效果,观察根尖细胞染色体数,叶片下表皮保卫细胞及叶片组织结构特征。结果表明:800μmol·L-1二甲戊灵浸泡24h,变异率达46.67%,0.05%秋水仙素处理48h,达42.22%,两种诱变剂诱导变异的差异虽不显著,但前者处理后材料存活率高于后者(前86.67%,后80.0%)。对变异的材料通过细胞学鉴定,发现两种诱变剂均能诱导出四倍体白花虎眼万年青。从处理时间短,材料死亡率低,对人畜伤害小,成本低,变异率较高以及两种诱变剂处理得到的多倍体气孔、叶片结构特征的相似性等综合条件考虑,可将二甲戊灵作为秋水仙素的替代品诱导多倍体。此外,对比二倍体与四倍体植株形态特征、叶片下表皮气孔数目及大小,可将气孔大小作为初步快速检测多倍体的有效方法。本试验用2种诱变剂诱导白花虎万年青多倍体,并从形态、气孔、叶片组织结构比较诱导前后差异,旨在为白花虎眼万青年多倍体新品种研究提供数据支持。     

Optical Properties of the Epidermis of Leek (Allium ampeloprasum L.) and Cabbage (Brassica oleracea L.) after Enhanced Ultraviolet-B Radiation

Abstract

The optical properties of the epidermis of two crops grown in Nordic countries, leek (Allium ampeloprasum L.) and cabbage (Brassica oleracea L.), were investigated after exposure to enhanced UV-B radiation in a glasshouse. Enhanced UV-B radiation was given to cabbage and leek during the growth period. A significant increase in extractable UV-absorbing pigments was found in the epidermis of UV-irradiated leek compared to control plants, whereas no such difference was found in the epidermis of cabbage. The pigments produced had absorption maxima at approximately 340 nm and were most likely flavonoids.     

用EST—SSR分子标记技术构建大白菜核心种质及其指纹图谱库

摘要利用EST-SSR分子标记对大白菜种质资源基因库中686份样品所代表的1900份大白菜种质资源进行分析研究。构建大白菜种质资源的核心种质并且形成核心种质的EST—SSR指纹图谱库。结果表明利用4组鉴定白菜品种的EST—SSR的特异性标记组合,获得近158个EST—SSR多态的标记,对大白菜种质资源基因库中686份样品所代表的1900份大白菜种质资源进行核心种质的构建提供了分析数据。形成的核心种质包括168份样品,占库存资源的8．8％,它的多态位点百分率保持了原群体的100％。所构建的核心种质涵盖了原资源的绝大部分区域来源的品种,包含了早、中、晚熟品种中所有典型的大白菜类型和其相关的特征特性。并进一步进行了核心种质资源遗传多样性分析。核心种质的EST—SSR指纹图谱库中,每一份样品的指纹都是唯一的,为登记、评价、整理、分发、繁殖等种质资源库的管理和育种者对其材料的利用提供了重要的有价值的信息。EST-SSR标记组合是构建中国大白菜核心种质及其指纹图谱的经济、高效的方法。     

Potassium efficiency of safflower (Carthamus tinctorius L.) and sunflower (Helianthus annuus L.)

The oil crop safflower may have a certain production potential under low‐input conditions (organic farming, developing countries), where the putatively low nutrient requirement is highly welcomed. However, current knowledge regarding the nutrient use efficiency of safflower as compared to similar oil crops is limited. It was thus the aim of this study to determine the potassium (K) use efficiency of safflower (Carthamus tinctorius L.) as compared to sunflower (Helianthus annuus L.). Safflower and sunflower were cultivated with increasing K supply in a mixture of equal volumes of sand, nutrient‐poor limed soil, and perlite in 5 L Mitscherlich pots. Both species responded strongly to increasing K supply with respect to growth and yield. Safflower out‐yielded sunflower at low K supply, while at high K level, the opposite was observed. Both species accumulated similar amounts of K in shoots at low K supply. Only at extremely low K supply, safflower took up more K than sunflower. However, achene yield of sunflower exceeded that of safflower at optimal and high K supply. Safflower utilized absorbed K more efficiently than sunflower to produce achene yield at suboptimal K supply in terms of both efficiency ratio and utilization index. The efficiency of a crop to use supplied or accumulated K for dry‐matter and achene production was interpreted in terms of Michaelis‐Menten kinetics, specifically addressing the shape of the yield response curve. Indeed, the efficiency of safflower to use K for growth and yield, analogue to a low K_m in enzyme kinetics, was higher than in sunflower, while the K supply or K accumulation required to initiate yield formation in safflower was significantly lower. Similarly, safflower had a lower external K requirement for achene yield than sunflower at low and optimal K supplies. It can be concluded that safflower represents a low‐input crop and outperforms sunflower on soils low in available K. The data analysis also reveals that using just one efficiency indicator is usually not sufficient to adequately describe the K efficiency of the crop under consideration.     

Regrowth in barley (Hordeum vulgare L.) and rye (Secale cereale L.)

Regrowth after cutting at four development stages, from heading to grain maturity, was investigated in a pot experiment containing three rye and four barley varieties. Regrowth in the barley varieties decreased strongly from heading to grain maturity. Rye generally showed stronger regrowth than barley after late cutting, but only the perennial variety ‘Soperta’ regenerated as many tillers at cutting as formed when harvested at the ripe grain stage. In both species, significant differences were found between varieties. The level of soluble carbohydrates reached a maximum between heading and maturity, but differences in regrowth could not be explained by such differences. Total N decreased from heading to maturity, except for perennial rye, where an increase was observed towards ripening. It is, however, uncertain whether this was an effect rather than a cause of the regrowth.     

Identification and overcoming barriers between Brassica rapa L. em. Metzg. and B. nigra (L.) Koch crosses for the resynthesis of B. juncea (L.) Czern.

Brassica juncea (2n = 36, AABB) is an amphidiploid derived from its diploid progenitor species B. rapa (2n = 20, AA) and B. nigra (2n = 16, BB). Resynthesis of B. juncea by exploiting the wider gene pool of the present day diploids offers a powerful tool for obtaining novel genetic variation. Hybridization between the two species is difficult because of the presence of crossability barriers. Barriers to hybridization were identified using Aniline Blue Fluorescence (ABF) method. Crosses were classified as having pre- or post-fertilization barriers based on whether less than or more than one per cent ovules showed pollen tube entry. Of the 23 crosses studied, seven crosses all with B. rapa as the female parent showed pre-fertilization barriers. Only 0 to 0.3 per cent ovules were fertilized in these crosses. The remaining 16 crosses, four with B. rapa as the female parent and 12 with B. nigra as the female parent, showed post-fertilization barriers. In crosses with pre-fertilization barriers use of bud pollination and stump pollination ensured or increased fertilization. These two simple techniques were used in combination with ovary-ovule culture to ensure recovery of hybrids. In crosses with post-fertilization barriers, ovary-ovule culture alone helped to obtain hybrids. Hybrids were obtained at higher frequency with the use of direct ovule culture compared to ovary-ovule culture. The F₁ plants obtained in vitro were multiplied on MS medium + 2 mg/l Kn + 0.2 mg/l IAA. These F₁ plants were confirmed as true hybrids through morphology, leaf isozymes and cytology. In all 17 hybrids were obtained of which three were amphidiploids.     

Phosphorus use Efficiency of Safflower (Carthamus tinctorius L.) and Sunflower (Helianthus annuus L.)

This study comparatively evaluates phosphorus (P) use efficiency of safflower and sunflower in view of identifying low input oil crops. Sunflower accumulated more P than safflower at all equivalent P supplies. Sunflower was more efficient at their best P supplies to utilize absorbed P than safflower in terms of efficiency ratio and utilization index. Yield response curves interpreting the functional relationship between nutrient supply and yield using Michaelis-Menten equation indicate that sunflower is less sensitive to inadequate P supply and thus more P-efficient than safflower with respect to yield, as the term ‘Km’ is lower for sunflower. The minimal P amount per pot required to trigger yield formation (term ‘Cmin’) was lower in sunflower than safflower. Harvest Index in sunflower out-yielded that of safflower at all P supplies. Critical deficiency contents of sunflower were lower than that for safflower. It can be concluded that safflower cannot be considered as low-input crop.     

Rheology of sea buckthorn (Hippophae rhamnoides L.) juice.

Juice extracted from sea buckthorn fruits was subjected to dynamic rheological measurements in a controlled stress rheometer. Sea buckthorn juice exhibited wide variations in flow behavior from pseudoplastic to dilitant with increasing temperature. The power law model suitably (r >/= 0.975, P相似文献