野生扁蓿豆种子硬实破除方法研究

为探求破除扁蓿豆种子硬实特性的最佳方法,采用砂纸打磨、切割、液氮处理、热水浸种、酸(98％浓硫酸、20％盐酸溶液)、碱(30％氢氧化钠溶液)等7种处理方法,开展了破除扁蓿豆种子硬实的效果研究.结果表明,切割处理能够完全破除种子硬实,种子发芽率达到99.00％;砂纸打磨后种子的硬实率可下降到7.50％,发芽率达到82.5...     

EMS处理对无芒雀麦种子萌发的研究

采用浓度分别为0.1%、0.3%、0.6%、0.9%、1.2%、1.5%和2.0%的甲基磺酸乙酯(EMS)对无芒雀麦种子进行浸种处理,分析EMS化学诱变剂对无芒雀麦种子发芽的诱变效应。结果表明:不同剂量的EMS处理对种子发芽具有抑制作用,且浓度越高,抑制作用越显著(p0.05)。无芒雀麦种子在不同浓度EMS诱变15h的条件下,种子发芽率、芽长和根长等与对照相比均有降低。以相对发芽率达半致死剂量为标准,EMS诱导无芒雀麦种子建立突变体库的适宜浓度为1.2%～1.5%,处理时间为15h。     

扁蓿豆种子发育形态解剖学研究

试验采用常规发芽法测定了扁蓿豆种子不同发育时期的发芽能力，并利用石蜡切片法对扁蓿豆种子发育进行了形态解剖学研究。结果表明：（1）栽培驯化后的直立型扁蓿豆种子千粒重和体积小于野生扁蓿豆。（2）种皮外的角质层、种皮的栅状细胞和种脐的结构是造成扁蓿豆种子硬实的重要原因之一。（3）开花后21天左右，种子形成成熟胚。成熟种胚存在3片子叶的异常现象。（4）胚乳发育属核型发育类型。（5）直立型扁蓿豆种子在黄熟后期发芽率最高为81%，硬实率最低为19%;野生扁蓿豆种子在黄熟前期发芽率最高为20%，硬实率也最高为80%。     

冷等离子体处理对2种豆科牧草种子发芽及幼苗生长的影响

对苜蓿和扁蓿豆种子进行＜20 s冷等离子体处理,并对种子发芽和幼苗特性变化情况进行了研究.结果发现:经不同剂量冷等离子体处理后,2种豆科牧草种子的发芽率有明显变化.其中260 W功率处理下苜蓿种子发芽率升高,其他功率处理下发芽受到抑制.在20 W、40 W和280 W功率处理下扁蓿豆种子发芽受到抑制,其他功率处理下发芽率较对照均有升高.对冷等离子体处理后发芽率最大的处理进行人工气候培养箱培养,25 d后扁蓿豆的苗高、根长与对照相比显著增加,根径和地上生物量影响不明显.苜蓿苗高、根长、根径和地上生物量均有显著增加.     

矿区复绿植物猪屎豆种子硬实率与萌发特性的研究

采用不同方法对猪屎豆种子进行处理,并测定了种子的硬实率、吸水率和发芽率.结果表明:猪屎豆种子有较高的硬实率,砂纸摩擦5 min可显著提高种子的吸水率;砂纸摩擦1～7 min均可提高种子的萌发率,摩擦5 min的发芽率达36％,而未摩擦种子发芽率只有11.3％.丙酮处理种子1、2、3、4h不能提高种子的发芽率,时间越长,种子的发芽率越低;过氧化氢处理对种子的催芽没有显著的效果;摩擦后种子在室温(10 ～27℃)、15、25、30、35℃条件下均能萌发;光照对种子的萌发没有显著的影响,说明猪屎豆种子是中光种子.     

扁蓿豆不同种质材料种子萌发期抗旱性比较

采用5个PEG渗透势梯度模拟干旱胁迫,以黄花苜蓿作对照,探讨了4份扁蓿豆种质材料种子萌发期的抗旱性。通过对种子相对发芽率、相对活力指数和半致死渗透胁迫强度3项指标的综合分析,扁蓿豆种质材料在种子萌发期的抗旱性高于黄花苜蓿,4份扁蓿豆种质材料抗旱性大小顺序为:材料4>材料1>材料3>材料2。其半致死渗透胁迫强度分别为:-1.30MPa、-1.03MPa、-0.85MPa、-0.78MPa。     

藜麦种子EMS诱变条件初探

为了确定藜麦种子EMS诱变处理的最佳条件,以自育白种藜麦种子为实验材料,设置5个浓度梯度(0.5%、1%、1.5%、2%、2.5%)的EMS缓冲液和4个时间梯度(8 h、10 h、12 h、14 h)进行诱变处理,通过连续观察种子发芽情况及生长状况,统计相关萌发指标,最终确定半致死剂量。结果表明,藜麦种子对低浓度EMS不敏感;高浓度EMS抑制藜麦种子发芽势和发芽率,且对种子发芽有一定的延迟作用;EMS缓冲液浓度、处理时间以及二者的互作对种子发芽势和发芽率均有显著影响;蒸馏水浸种2 h后,1.5%EMS浓度处理12 h为诱变的最佳条件,其相对致死率为48.7%;另外,2%、8 h及2%、10 h相对致死率较接近半致死剂量,为可选择的组合。     

扁穗雀麦种子休眠期和发芽特性的初步研究

以江夏扁穗雀麦种子为试验材料,研究了扁穗雀麦种子发芽和休眠特征.结果表明,不同时期新收获的扁穗雀麦种子几乎不发芽,风干种子发芽率最高为4％,存在严重的休眠现象.随着种子干燥贮藏时间的延长,发芽率、发芽势和发芽指数逐渐增加,发芽开始时间提前.贮藏63d种子萌发出现急剧变化,发芽率达51.33％,与前期处理差异显著(p＜0.05);78～81d发芽率超过85％,休眠解除,发芽开始时间提前至第6天.不同成熟期收获的扁穗雀麦种子在解除休眠后发芽特性略有差异,但总的来说,成熟度高的种子在贮藏3个月后发芽率和发芽指数均较高.     

喀斯特地区造林先锋树种任豆种子萌发特性研究

采用了石英砂和砂纸摩擦、氢氧化钠溶液浸种、热水浸种、浓硫酸浸种和浓硝酸浸种等5种不同方法对任豆种子进行处理,并对不同处理方式所得到的数据进行比较分析。结果表明：利用石英砂和砂纸摩擦,不仅可以明显改善种皮的通透性,提高任豆种子的发芽势和发芽率,而且操作简便,设备简单,无污染,是一种值得考虑的方法;采用不同浓度的硫酸浸种,种子的吸水性能得到明显的改善,尤其是用浓硫酸浸种30min,任豆种子的发芽率可高这99．0％,但废酸的处理比较麻烦,成本较高,并且有一定的环境风险;用80℃的热水浸种,其发芽率也较高,可达75．0％;用浓度为30％的氢氧化钠溶液浸种,任豆种子的发芽率没有显著的变化;用浓硝酸处理,随着处理时间的增加,发芽率逐步增加,浸种时间为30min的发芽率最高（45．5％）。当浸种时间大于30min时,任豆种子的发芽率反而有所下降。综合成本、技术难度及环境风险等因素考虑,热水浸泡处理方法,可作为任豆种子发芽处理的首选方法。     

化学诱变剂及赤霉素对狭叶薰衣草种子萌发的影响

采用不同种类的化学诱变剂和赤霉素处理狭叶薰衣草种子,研究其萌发情况。结果表明:浓度为1.0%的EMS浸种8 h,对狭叶薰衣草种子的发芽势和发芽率均具有显著或极显著的促进作用,而2%的EMS浸种对狭叶薰衣草种子萌发则有显著的抑制作用;不同浓度的秋水仙素浸种对狭叶薰衣草种子发芽势和发芽率均有一定的促进作用,但均在一定程度上推迟种子的萌发。同时,恒温条件下用秋水仙素浸种,种子萌发更快,且发芽率较室温高;GA3处理能显著提高狭叶薰衣草种子的发芽率和发芽势,在GA3浓度为200 mol/L,处理8 h时,狭叶薰衣草种子发芽势和发芽率分别是对照的3.43倍和5.86倍,并与对照差异达极显著水平。     

分葱对黄瓜、萝卜和白菜的化感作用

以黄瓜（Cucumis sativus L.）,萝卜（Raphanus sativus L.）和白菜（Brassica chinensis L.）3种蔬菜作物为受体,通过种子萌发试验及幼苗生长试验,对分葱（Allium fistulosum L.var.caespitosum Makino）根系及其地上部水浸液的化感作用进行了初步研究。结果表明：分葱根系和地上部水浸液对黄瓜、萝卜和白菜具有一定的化感作用。对黄瓜和萝卜的萌发有一定的抑制作用,而对其幼苗生长有一定的促进作用;对白菜的萌发表现为低浓度促进高浓度抑制,而对其幼苗生长有一定的抑制作用。因此,在蔬菜栽培制度中,分葱可与黄瓜和萝卜进行合理的轮作与间套作;但可能不适宜与白菜进行轮作或间套作。     

新铁炮百合种子萌发的研究

本文对新铁炮百合进行了种子发芽的研究试验,试验采用PEG引发处理和低温浸润的方式.结果表明：新铁炮百合种子通过PEG引发处理来提高其发芽能力.同时,新铁炮百合种子还可以通过低温浸润处理来提高其发芽能力.经过低温处理后的种子,发芽率随着冷藏天数的增加而增加,还可以增加种子发芽的整齐性.     

Genotype-environment interaction for seed yield and ODAP concentration of Lathyrus sativus L. and L. cicera L. in Mediterranean-type environments

In 1994, 407 L. sativus and 96 L. cicera lines were evaluated for phenology, seed yield and seed ODAP (a neurotoxin) concentration in the Mediterranean-type climate of south-western Australia. A selected number of lines from this study were grown at three sites in south-western Australia in 1995 and 1996, to examine genotype-environment interactions on seed yield and ODAP concentration in the seed of the two Lathyrus spp. Principal components analysis showed that L. sativus lines grown in 1995 and 1996 could be divided into two geographical origins: Indian sub-continent and Mediterranean/European. Those lines of Mediterranean/European origin were consistently higher yielding (both in 1994 and 1995/96), with much larger seeds and later phenology. In L. cicera seed yield was closely associated with greater mean seed weight and to a lesser extent with early phenology. The genotype-environment study indicated that higher yielding lines of both species generally responded to favourable environments; in the case of L. sativus the Mediterranean/European lines and for L. cicera the larger seeded, earlier phenology lines. For both species, genotype was the most important determinant of ODAP concentration and environment had less influence. Genotype-environment interactions had no effect on seed ODAP concentrations. In terms of seed yield, both species showed substantial potential in the environments tested. Further improvements in adaptation, seed yield and reduction in ODAP are possible in both species. This revised version was published online in August 2006 with corrections to the Cover Date.     

Breaking breeding barriers in Lycopersicon. 4. Breakdown of unilateral incompatibility between L. peruvianum (L.) Mill. and L. esculentum Mill.

Summary A brief survey is given of the occurrence of unilateral incompatibility between populations. It is reported how the unilateral incompatibility between L. peruvianum and L. esculentum has been broken stepwise by inbreeding with the aid of self-compatibility in L. peruvianum and selection in this self-compatible L. peruvianum material of absence of L. esculentum pollen tube inhibition, and how L. peruvianum material has been developed on which large-scale L. peruvianum x L. esculentum hybrid production is possible. It is concluded that the unilateral incompatibility between L. esculentum and L. peruvianum consists of a complex of separate processes.     

草地早熟禾对多年生黑麦草种苗化感影响的研究

以草地早熟禾8个品种为供体,按照培养皿生物检测方法,研究其浓度为10%的茎液浸提液对多年生黑麦草两个品种的种子萌发和幼苗生长的化感效应。结果表明,草地早熟禾茎叶浸提液对多年生黑麦草的发芽率、根长、苗长及幼苗鲜重等均存在化感作用的潜势,其中肯塔基对多年生黑麦草的化感抑制最强,普拉蒂尼对荣誉种子萌发、公园对荣誉的幼苗生长的化感抑制也较明显。     

Inheritance of groat protein percentage in Avena sativa L. × A. Fatua L. Crosses

Summary Gene action and heritability of groat protein percentage were determined in F₁, F₂, and F₃ generations of nine crosses between three Avena sativa L. cultivars and three A. fatua L. selections. Relationships among groat protein percentage, grain yield, and 100-seed weight also were evaluated. The three A. sativa parents were Dal (high grain yield and intermediate groat protein percentage), Goodland (low grain yield and high groat protein percentage), and Stout (high grain yield and low groat protein percentage). The three A. fatua parents were chosen for the study on the basis of vigorous plant growth and high groat protein percentage. The study was conducted at Madison, Wisconsin in 1979 and 1980.There was partial dominance towards low groat protein percentage. Narrow sense heritability estimates for groat protein percentage were low in Dal and Goodland crosses and intermediate in Stout crosses. In the F₂ generation, groat protein percentage was significantly higher in shattering than in nonshattering plants in 1979, but not in 1980. There were significant, positive correlations between groat protein percentage, 100-seed weight, and grain yield in F₁ and F₂ generations, but they were not large numerically. Relationships among these traits were either negative or nonsignificant in the F₃ generation. Although our results indicated that selection for higher groat protein percentage is possible when a low protein A. sativa cultivar is used, most of our simple cross progenies from A. sativa x A. fatua crosses had weak straw and were susceptible to crown rust (Puccinia coronata Cda. var. avenae Fraser and Led.).     

Allelopathic Effect of Eucalyptus globulus Labill. on Cyperus rotundus L. and Cynodon dactylon L. Pers.

The allelopathic potential of Eucalyptus globulus Labill. (gum tree) fresh and dried leaf leachates was studied using two perennial weeds, viz. purple nutsedge (Cyperus rotundus L.) and bermuda grass (Cynodon dactylon L. Pers) as test weeds. Aqueous leachate of fresh leaves of eucalyptus significantly suppressed the establishment of vegetative propagules and early seedling growth of the weeds. Leachate of fresh leaf cuttings had growth inhibitory effect on bermuda grass but showed growth promotion effect on purple nutsedge. Similarly the leachate of dried leaves of eucalyptus had differential influence on the growth of the two weeds. There is a possibility to harness the allelochemicals of eucalyptus leaves as herbicides for the management of these perennial weeds.     

温度和培养介质对细叶杜香种子萌发的影响

本实验研究了温度和培养介质对细叶杜香种子萌发的影响,确定了细叶杜香种子萌发的最适温度和最佳培养介质,为进一步开发利用细叶杜香提供理论依据.     

Hybridization of Sinapis alba L. and Brassica napus L. via Embryo Rescue

Embryo rescue techniques were used to obtain hybrids between Sinapis alba L. (white mustard) and Brassica napus L. (oilseed rape) with the goal of improving the disease tolerance of oilseed rape. Hybrid plants with 31 or 43 chromosomes were only recovered, when S. alba, was used as the female parent. One hybrid was obtained from the cross S. alba L. cv. ‘Kirby’×B. napus L. cv. ‘Topas’, while 26 hybrids were obtained, when various S. alba L. cultivars were pollinated with the rapid cycling B. napus line CrGC 5006. All F₁, hybrid plants were male sterile; however, the first generation backcross to B. napus L., also obtained by embryo rescue, produced plants with 50 chromosomes and 61–84 % pollen viability. Second backcross generation seed was produced by normal sexual crossing. Preliminary cytological analyses of pollen mother cells of hybrid plants suggests the possibility of genetic exchange between the two species.