孟士德薰衣草种子萌芽生物学特性研究

以孟士德薰衣草为试验材料,研究温度、光照以及赤霉素等外界条件对孟士德薰衣草种子萌发的影响,以期找到提高孟士德薰衣草种子萌芽率的有效方法,为孟士德薰衣草的播种繁殖及育种工作提供科学的理论依据。结果表明:(1)孟士德薰衣草的种子黑褐色,表皮光滑,种皮坚硬角质化,外包蜡质,种子千粒质量(0.947±0.045)g;(2)200 mg/L赤霉素浸泡处理6 h孟士德薰衣草种子萌芽率最高,达到94.6%;(3)15℃黑暗环境下孟士德薰衣草种子萌芽率最高,达到95.2%,20℃次之,为94.6%,但相比15℃幼苗长势更好;(4)光照10 h处理有利于孟士德薰衣草种子萌芽,萌芽率为94.6%,且幼苗长势最好;(5)采用不同浓度GA3对孟士德薰衣草种子进行处理,以200 mg/L的GA3处理种子萌芽效果最佳,萌芽率达到94.0%。     

超级火炬种子繁殖技术初报

对超级火炬进行人工授粉、基质播种及移栽管理试验。结果表明:超级火炬凤梨人工授粉成功获得种子约180 d。种子播种于2种泥炭基质15~25 d内萌芽,其萌芽率8.27%。来源于不同植株的种子,不同基质播的种子其萌芽率有差异。从种子萌发形成二级苗需18个月。种子萌发到形成二级苗成活率达91.64%,变异率达13.32%。     

羽扇豆在西昌的播种育苗技术初探

通过在西昌开展羽扇豆播种育苗试验,结果表明,条播的羽扇豆(种子不处理)种子出芽率高于穴盘内播种(种子粗砂处理)的羽扇豆种子;大棚内萌芽较容易,种子不用处理,直接开沟条播萌芽率可达96%以上。     

种衣剂对葡萄杂交种子萌发及成苗的影响

以种衣剂处理葡萄6个不同杂交组合的种子,研究种衣剂对其萌芽率、出苗率、成苗率以及苗期立枯病发病率的影响。结果表明,种衣剂处理葡萄各杂交组合种子的萌芽率均有所提高,且对四倍体为母本的杂交种子影响较大;种衣剂对苗期立枯病有很好的防治效果,发病率控制在10.0%以内,成苗率以欧亚种作母本最高,可达到75.2%。     

芋种子萌发特性的研究

以仰光×乐平及仰光×霞山2种杂交种子为试材,探究消毒方法、光照、温度、播种基质对芋种子萌发和生长的影响。结果表明:8%Na Cl O(无水酒精稀释)处理9min后用无水酒精清洗种子是最佳的芋种子消毒方法;种子或珍珠岩消毒对种子的萌发和子叶的生长无显著影响,但在有菌条件下,生长后期衍生出的细菌或真菌会影响子叶的后续生长;芋种子是喜光性种子,种子萌发的适宜温度为25~30℃;在培养土中,芋种子不萌发,湿润滤纸、无菌水、珍珠岩、沙子和MS培养基中芋种子的发芽率较高,但仅沙子和MS培养基中幼苗生长健壮;移栽于培养土后幼苗生长良好,成活率高达95%。     

越橘种子破除休眠、萌发及快速成苗方案优化

【目的】优化越橘种子播种方法,解决越橘杂交种子萌发率低、成苗慢的关键问题。【方法】以越橘品种‘蓝丰’‘北陆’‘杜克’及杂交种子为试材,进行不同赤霉素质量浓度、贮藏条件和基质条件下的播种试验,调查萌发率及幼苗生长,优化播种方案。【结果】1)供试越橘品种种子对赤霉素浓度的敏感度存在差异,但均以400 mg·L~(-1)赤霉素浸种20h种子萌发率最高;2)在400 mg·L~(-1)赤霉素处理下,新鲜的种子萌发率最高(88%,60 d),其次是自然阴干4℃贮藏、新鲜种子4℃贮藏和自然阴干室温贮藏的种子(79%、78%和80%,60 d),低温冷冻严重影响越橘种子活力;3)水苔作为播种基质越橘种子萌发率高(88%,60 d),而河沙最低;越橘幼苗在混合营养土(V草炭∶V园土∶V腐熟牛粪/有机肥=2∶1∶0.1,每m31~1.5 kg硫磺)中的生长状态最佳。【结论】新鲜的越橘种子或经自然阴干4℃贮藏后的种子,使用400 mg·L~(-1)赤霉素浸种20 h,采用上层水苔下层混合营养土的基质播种,能显著提高种子萌发率和幼苗生长速度,该措施成本低、易操作、效果佳,可满足规模化越橘育种需要。     

不同落叶时期和落叶方式对设施桃无需冷栽培萌芽率的影响

以4年生"中农金辉"油桃为试材,在设施无需冷栽培方式下,采用不同落叶时期和落叶方式对油桃进行处理,分析了不同处理方式对油桃萌芽率的影响。结果表明:在设施桃无需冷栽培中,不同落叶时期对萌芽率的影响差别很大,从8月开始,萌芽率逐渐升高,在9月中下旬时萌芽率达到最高,之后萌芽率开始下降,到10月下旬时萌芽率降低为0%;不同落叶方式同样对萌芽率的影响很大,其中避光闷棚落叶的萌芽率最高,与人工摘叶和8%尿素脱叶相比差异极显著。由此筛选出了设施桃无需冷栽培方式下最适宜的落叶时期为9月中下旬,最适宜的落叶方式为避光闷棚落叶。     

牛鼻栓种子萌发特性研究

通过对牛鼻栓的种子进行不同浓度GA_3及不同贮藏方式的处理,进行发芽试验,总结牛鼻栓种子的一些萌发规律,得出最佳处理方式和最高萌芽率的结论。阻碍种子萌发的因素主要是坚硬的种皮,而用自然沙藏或GA_3浸泡等方式可以打破休眠。自然沙藏4个月萌芽率最高,为98%;其次为以浓度400μg/ml的GA_3浸泡48h后恒温冷藏处理3个月,萌芽率为97%。     

不同浓度赤霉素对野生蕉种子萌发及成苗的影响

为探索出野生蕉种子萌发最佳赤霉素(GA3)浓度,本研究通过在基本培养基上添加不同浓度GA3含量,研究其对野生蕉种子萌芽及成苗的影响。结果表明,添加有GA3的培养基均能促进野生蕉种子的萌芽率和成苗率,种子初始萌芽时间均要比对照提早40~50 d左右。其中以GA3浓度为15 mg·L-1培养基效果最佳,其萌芽率、成苗率和生根率分别比对照提高50.0%、40.0%和23.3%。     

壮瑶药水罗伞种子萌发特性及播种育苗研究

在不同温度、光照、贮藏条件、浸种处理下研究水罗伞种子的发芽特性,比较3种不同基质下的种苗生长发育情况。结果表明:光照条件对水罗伞种子萌发的影响不明显,当温度在15/25℃及25℃时种子具有较高的发芽率,浸种24h发芽率最高可达到96.7%,室温下贮藏60d后种子发芽率明显下降。3种不同播种基质间种子发芽率没有明显差异。随着苗木的生长,播种180d后调查显示,以疏松而富有营养的泥炭土条件下其根长、根重、全株重值均最大,苗木生长最好。     

不同基质含水量对秋播花椰菜工厂化育苗质量的影响

运用南京蔬菜工厂化育苗中心先进的仪器设备,经精心设计后开展试验研究,旨在探索出不同基质含水量与秋播花椰菜工厂化育苗质量间的关系。将秋季花椰菜育苗划分为播种发茅期、子叶期、1叶1心期、2～5叶期、4～5叶期5个生长阶段,在各阶段均设定4个不同的基质水分处理值进行观测比较分析。试验结果表明：秋季花椰菜育苗5个生长阶段的最佳基质含水量依次为基质最大持水量的85％、65％、65％、75％和75％;另可提供秋播花椰菜优质种苗相应标准参考值为：苗龄4～5叶,株高7．47cm,茎粗3．64mm,最大节间距o．78cm,最大叶形指数1．44。     

杜鹃属植物种子育苗研究

 采用不同基质、播种时间进行杜鹃属植物种子育苗试验。结果表明: ①种子萌发和幼苗生长最适温度为16～20℃, 庐山地区播种以5月上旬最佳; 材料较多的5个亚属供试种发芽速度以羊踯躅亚属最快, 常绿杜鹃亚属、映山红亚属、杜鹃亚属居中, 马银花亚属最慢。②“腐殖土+苔藓”基质成苗率及幼苗生长表现优于“腐殖土”。③与庐山地理位置越近、气候差异越小, 育苗越易成功, 原产长江中下游、中低海拔的种表现极佳。④不同系统位置的物种育苗效果依次为映山红亚属>马银花亚属>羊踯躅亚属>常绿杜鹃亚属>杜鹃亚属。⑤播种及幼苗期的管理是育苗成败的关键。     

A validated mechanistic model of carrot (Daucus carota L.) growth

A mechanistic model of carrot vegetative and root development was constructed. This model determined canopy photosynthesis over a day, assimilates were then partitioned into either roots or leaves via temperature dependent partitioning coefficients. Assimilates were lost via terms describing growth and maintenance respiration. The model was calibrated on data from four different carrot cultivars, originating from the UK (Autumn King), Syria (Carrot_S), Poland (Dolanka) and Russia (Hibinskaja), grown in controlled environment glasshouse compartments at one of six temperatures (9–30 °C) repeated over three sowing dates. Calibration of the model showed that it could account for between 83 and 95% of the variance in carrot plant and root dry weights. The model was then validated using independent data from the same cultivars of carrots grown in the field at Reading. In this instance, the model accounted for 75 and 79% of the variance in plant and root weight, respectively. Two other independent data sets were used to validate the model, including carrot of a different cultivar (Panther) grown in phytotrons at temperatures between 9 and 21 °C, at two different locations and over a three sowing dates. In this instance, the model accounted for between 63 and 69% of the variance in root weight. The model also predicted that if ambient carbon dioxide levels increased from 348 to 551 μmol mol⁻¹, root dry weight would increase by 12%, which is within the margin of error of the experimental value of 16% reported in the literature. The model can therefore be used to study the potential impacts of global climate change on carrot production, as well as to rapidly predict whether germplasm is suited to any particular environment.     

Effects of pre-sowing seed treatments and temperatures on tomato seed germination and seedling emergence

Sowing pre-germinated seeds with radicles 2–3 mm long reduced the time from sowing to seedling emergence to 17 days compared with 41 days in untreated seeds at soil temperatures of 10°C, and to 5 days compared with 11 days at 18°C. Sowing pre-germinated seeds also improved percentage seedling emergence and reduced the variability of times of emergence of individual seedlings. Seeds imbibed for 56 h before sowing (radicles just emerging) emerged about 3 days earlier at both 10°C and 18°C than untreated seeds. Seeds soaked in a solution containing 1.5% each of KNO₃ and K₃PO₄ for 5 days at 24°C, or in “Carbowax 20 M” for 20 days at 15°C, and then dried before sowing, gave results similar to imbibed seeds. Soaking seeds in 70% of their weight of water followed by drying for different lengths of time and for different numbers of cycles of wetting and drying did not improve germination or seedling emergence.     

Field Trials of,Dichloro-Diphenyl-Trichloroethane (D.D.T.) Against the Raspberry Beetle (Byturus Tomentosus Fabr.)

Summary

Crops of early leek cv. Prelina were grown in four experiments at Wellesbourne and in Cornwall from 1995 to 1997. Treatments applied included time of sowing, plant raising temperature, transplant type and covering regime. There was no effect of plant raising temperature on marketable yield or on the percentage of flowering plants. It is suggested that with cv. Prelina it is particularly the conditions during early field growth that affect the ability to flower. Larger plants at transplanting, resulting from earlier sowing or the use of peat blocks, increased the percentage of flowering plants but effects of fleece cover were variable, depending upon how close temperatures were to the optimum for vernalization, which was shown to be close to 78C. It is suggested that rather than planting early, with subsequent air temperatures near to the optimum for vernalization, which will result in high levels of bolters, it would be better to delay transplanting. Plants can then be maintained at a raising temperature that is higher than the optimum for vernalization and transplanted when there is a strong probability of air temperatures being higher. Simple models have been developed to predict first, the rate of increase of leek diameter and secondly, the rate of flower stalk extension, so that it will be possible to predict when the crop will be large enough to harvest and when flowering stalks will become unacceptably long.     

象牙白花兰种子及茎尖培养与原球茎形态发生

 象牙白花兰授粉后5 个月的种子开始具有较高的萌发率; 椰乳或适量激素有利于种子的萌发;种子在萌发后胚发育形成原球茎, 原球茎经过增殖, 分化出叶片和根系, 形成完整的小植株。从播种到小植株的形成历时约7 个月。茎尖在MS + NAA 0. 1 + BA 3. 0 (单位: mg·L^-1 , 下同) + 椰乳10 %的培养基上诱导产生原球茎; 原球茎在MS + NAA 0. 1 + BA 5. 0 的培养基上增殖, 在无激素培养基上分化成芽; 小芽在附加7 %香蕉汁和3 %马铃薯汁的1/ 2 MS 培养基上诱导出根而再生完整小植株。不同pH 值、光照强度和培养方式对增殖效果有显著影响。     

猕猴桃种子萌发特性研究

用物理和化学方法处理猕猴桃种子,研究其种子萌发特性。结果表明:用5~20℃变温处理比0~15℃变温处理种子萌发早,在处理后第18天开始萌发,第25天接近最大值,低变温处理在第37天开始萌发,第60天接近最大值;在猕猴桃种子适宜萌发的条件下,用赤霉素处理的种子发芽势和发芽率明显高于对照,尤其是发芽势明显增强,平均发芽数在播后第20天(发芽势记载日期)比对照高38.3%~80.1%,在播后第19天高67.2%~140.4%,同时萌发的时间缩短,比对照早2~4 d;不同浓度处理之间的发芽率随着浓度的增加也有增效作用,浓度越大,发芽率越高,在播后第19天的发芽率在39.3%~56.5%之间,第24天的发芽率在94.3%~99%之间。     

紫豇豆“绵紫豇1号”播种期及密度试验

摘要：为研究紫豇豆品种绵紫豇1号的配套栽培技术,为其栽培及推广提供科学依据,进行了6个播种期及3个种植密度的双因子试验,分析不同播种期与密度对绵紫豇1号的生育期、植物学性状和产量的影响。结果表明：对绵紫豇1号豇豆产量的影响顺序依次为播种期＞播种期与密度互作＞密度;产量随播种期的推迟呈下降的趋势,随密度的增大呈先升后降趋势。综合得出,绵紫豇1号在四川地区的适宜播种期为3月25日前后,播种期不宜太迟,太迟会影响产量;在土壤中上等肥力水平下的适宜种植密度为667 m2栽8 100株。     

平邑甜茶MhSnRK1在番茄中超表达对种子萌发及幼苗生长的影响

为探讨蔗糖非发酵–1–相关蛋白激酶–1（SnRK1）对种子萌发及幼苗生长的调控作用,以超表达平邑甜茶MhSnRK1的番茄株系O-7、O-9和其野生型（WT）为试材,研究MhSnRK1对番茄种子萌发及幼苗生长发育的影响。结果表明,WT、O-7和O-9在MS培养基中种子发芽率均为100%,在MS + 100 mmol · L-1海藻糖培养基中发芽率显著降低,分别为23.3%、70.3%和67.7%;在MS培养基中O-7和O-9的SnRK1活性分别比WT高12.1%和2.3%,在海藻糖培养基中WT、O-7和O-9比在MS培养基中分别降低41.5%、35.5%和27.5%,O-7和O-9仍高于WT,可见在一定范围内较高的SnRK1活性促进种子的萌发。播种后14 d,与其他培养基中相比,海藻糖培养基中幼苗主根的长度最短,其中WT显著短于O-7和O-9;幼苗下胚轴的伸长较MS培养基中明显受到抑制,且WT受抑制的程度更大;在海藻糖培养基中添加0.3 mg · g-1的IAA,WT下胚轴伸长受到的抑制得到解除。播种后30 d,海藻糖培养基中,与O-7和O-9相比,WT表现为子叶平整肥厚,真叶发育良好,叶面积较大,叶绿素含量显著高于 O-7和O-9。上述结果表明,平邑甜茶MhSnRK1在番茄中超表达调控种子的萌发及幼苗的生长;在一定范围内,较高的SnRK1活性促进种子的萌发、抑制幼苗主根和下胚轴的伸长,较低的SnRK1活性更有利于幼苗的生长发育。