矮壮素对苦草矮化特征及生理指标的影响

沉水植物生长过高引起水体污染问题受到人们高度重视。本文在实验室模拟条件下,研究了0(CK)、0.01、0.02、0.10、0.20、0.50、0.75、1.00和1.25g.L-1共9个不同浓度矮壮素对苦草(Vallisnerianatans)矮化特征及生理指标的影响。结果表明:不同浓度处理30d后苦草株高具有显著差异性(P<0.05),且浓度越高矮化效果越显著;矮壮素使苦草叶宽增加、根长缩短,其中浓度在0.02～0.20g.L-1时苦草根冠比增加,浓度在0.01～0.50g.L-1时苦草株数增加明显;矮壮素浓度在0.10～0.50g.L-1时,苦草湿重增加61%～123%,将从水中或底泥中吸收更多N、P等营养物质,增强其净化水质的能力;当矮壮素浓度为0.02g.L-1时,不仅苦草矮化的效果较好,占据空间相对较小,而且苦草根长生长较长,根冠比较大,叶绿素含量增加,SOD、POD酶活性升高,苦草抗逆性增强,延缓植株衰老。因此,0.02g.L-1浓度矮壮素对苦草矮化较为适宜。     

多效唑和矮壮素对盆栽彩色马蹄莲的矮化实验

采用200～400 mg*L-1多效唑(PP333)和1 000～2 000 mg*L-1矮壮素(CCC)对处于生长中期的2个彩色马蹄莲(Zantedeschia antedeschia)盆栽品种进行矮化处理,结果显示彩色马蹄莲的株型明显矮化,茎杆增粗.统计分析表明:PP333处理的矮化效果较明显,其中以300 mg*L-1效果最佳,说明PP333对设施栽培条件下彩色马蹄莲的防徒长、抗倒伏的矮化处理有实用价值.     

凯特杏花粉的离体培养及影响因子分析

采用离体培养法,在不同培养基组分含量、pH值、温度及植物生长调节物质的培养条件下,对凯特杏(Prunus armeniacaL.cv Katy)花粉的离体萌发和花粉管生长状况进行观察研究。结果表明:(1)凯特杏花粉离体萌发及花粉管生长的适宜培养基为20%蔗糖 0.04%硼酸 0.01?Cl2,最适pH为6.0,最适温度为20℃,培养20 h后,花粉的萌发率达68.76%,花粉管长度达1 083.53μm。(2)不同植物生长调节物质对花粉萌发和花粉管生长作用不同,赤霉素浓度为5~8 mg/L、矮壮素浓度为10~150 mg/L、多效唑浓度为5~10 mg/L时对凯特杏花粉萌发和花粉管生长都有促进作用,但国光丁酰肼对凯特杏花粉萌发和花粉管生长均有抑制作用。     

多效唑和缩节胺对现蕾前忍冬枝叶生长及花蕾性状和有效成分含量的影响

以忍冬品种‘九丰一号’(Lonicera japonica‘Jiufeng 1’)为实验材料,采用叶面喷施方法研究了不同质量浓度多效唑和缩节胺对现蕾前(抽枝生长初期)枝叶生长和叶片叶绿素含量以及花蕾性状和花蕾中绿原酸和总黄酮含量的影响。结果显示:分别喷施100、400、700和1 000 mg·L-1多效唑和50、100、150和200 mg·L-1缩节胺后,多数处理组的开花枝条数、着花节数和叶绿素含量较对照CK1(水)有不同程度提高,但叶面积差异不明显。随处理时间延长,各处理组枝条节间长度总体上呈逐渐增加的趋势,其中多数处理组枝条节间长度增长缓慢。各处理的花蕾长度、百蕾鲜质量和干质量总体上小于CK1,而花蕾折干率、总黄酮含量和绿原酸含量显著或不显著高于CK1。此外,在喷施多效唑和缩节胺的同时喷施质量体积分数1.0%尿素和质量体积分数0.1%硼砂,忍冬的叶面积、着花节数、花蕾长度、折干率、百蕾鲜质量和干质量总体上有所提高,而绿原酸含量降低,但各指标的差异总体较小。研究结果表明:喷施适量多效唑和缩节胺可调控忍冬枝条生长,并能提高花蕾中总黄酮和绿原酸含量。     

多效唑与水稻育秧

多效唑是我国“九五”期间研究和推广应用取得很大成效的植物生长调节剂。多效唑应用于二晚育秧上的效果最佳。我国长江中下游诸省,二晚育秧期正值夏季高温,秧苗生长迅速,容易长成徒长弱苗,移栽本田后败苗严重,返青慢,延误季节,影响产量。多效唑能有效地培育二晚壮秧,从而达到增产的目的。多效唑对二晚壮秧有如下作用：（l）良好的控长矮化效应。经多效唑处理的秧苗,矮化作用见效快,持续期合适。喷后2～3天即可明显地表现出矮化效果,持续期为35～45天。移栽时处理,秧叶片和叶鞘短宽而重,基部增粗,株高约比对照矮1／3左右,表…     

不同质量浓度多效唑对碗莲品种'火花'生长和 叶片部分生理指标的影响

研究了不同质量浓度(0~50 mg·L-1)多效唑对碗莲(Nelumbo nucifera Gaertn.)品种'火花'('Huohua')生长的影响及多效唑处理过程中叶片部分生理指标的变化,并进行了隶属函数值分析和相关性分析.结果表明:质量浓度10~50 mg·L-1多效唑处理抑制碗莲品种'火花'生长.随着多效唑质量浓度提高,立叶数、立叶长、立叶宽、立叶高、花径、花高和开花总数总体上呈逐渐降低的趋势,且总体上与对照组(质量浓度0 mg·L-1多效唑)差异显著.随着处理时间延长,质量浓度10~50 mg·L-1多效唑处理组叶片中丙二醛(MDA)含量、过氧化物酶(POD)活性和多酚氧化酶(PPO)活性的变化趋势各异;质量浓度10~50 mg·L-1多效唑处理组叶片中可溶性蛋白质含量和超氧化物歧化酶(SOD)活性,以及质量浓度10、20和30 mg·L-1多效唑处理组叶片中过氧化氢酶(CAT)活性总体上呈先升高后降低的变化趋势,而质量浓度40和50 mg·L-1多效唑处理组叶片中CAT活性则呈逐渐降低的变化趋势.相关性分析结果表明:碗莲品种'火花'生长指标的隶属函数值间以及叶片中可溶性蛋白质含量和POD活性的隶属函数值与生长指标的隶属函数值间的相关性总体在0.05或0.01水平上显著.研究结果显示:质量浓度10、20和30 mg·L-1多效唑处理可有效控制碗莲品种'火花'生长,提高其观赏性;且其生长指标以及叶片中可溶性蛋白质含量和POD活性可以作为判断碗莲品种'火花'矮化效果的可靠、简易指标.     

多效唑对水仙生长发育的影响

为提高水仙的观赏价值,探讨复合多效唑对水仙生长发育的影响,用不同的多效唑溶液对水仙鳞茎进行处理。结果表明:多效唑能抑制水仙的营养生长,使植株矮化粗壮,叶片碧绿、挺拔,不易倒伏,根白、短而壮;复合多效唑配方使平均叶长减少37.7%,花期延长2d,花朵直径增加18.3%,延缓黄化叶片的出现,减慢叶肉薄壁细胞及其中叶绿体的解体,在后期维管束的结构相对完整,有效提高观赏价值。     

多效唑和脱落酸对白兰花内源激素及光合速率的影响

以白兰花为试材,采用土施、喷施多效唑和脱落酸的方式对其植株进行处理,观察株高和开花情况,同时结合主要内源激素含量及光合特性进行分析。结果表明：经处理后,白兰花内源激素IAA、GA3、Z、ZR和ABA含量呈现不同的变化规律,且光合速率也出现明显的变化;经处理后的植株明显矮化,盛花期提前,开花数量大幅度增加,且开花次数也显著增多。其中以土施和喷施多效唑与脱落酸的效果最好,处理后的植株只有正常株高的40%～50%,开花数却达到正常植株的2.3倍。     

多效唑浸种对渗透胁迫下玉米根边缘细胞发生的影响

以‘农大108’玉米种子为材料,采用不同浓度(50、100、150、200、250、300、350 mg·L-1)的多效唑溶液进行浸种处理,研究其对渗透胁迫(20％ PEG-6000)下玉米种子萌发、根系生长和根系边缘细胞数目、活性及黏胶层厚度的影响.结果表明:与对照相比,渗透处理抑制了玉米种子露白与根系生长,增加了边缘细胞数目与黏胶层厚度.预先用多效唑浸种后再进行渗透胁迫处理进一步降低了主根的长度,但增加侧根的生长而使根系鲜重增加,进一步增加了根边缘细胞黏胶层厚度,在一定程度上减少了由于渗透胁迫造成的边缘细胞数目的增加程度.无论是渗透处理还是预先用多效唑浸种处理对边缘细胞活性的影响均不大.可见,多效唑浸种能够增加玉米根系的抗旱能力与边缘细胞黏胶层厚度的增加有关,而与边缘细胞数目、活性的关系不大;多效唑浸种溶液的适宜浓度范围为200～250 mg·L-1.     

生长调节剂调控龙眼冲梢的研究

为高效、安全地调控龙眼冲梢,在龙眼花芽形态分化开始期(露红点期)和花穗主轴长6～9 cm的花穗展叶期,施用生长调节剂,比较了不同方法调控龙眼冲梢的效果。结果发现龙眼花芽形态分化开始期树冠喷施200 mg/kg乙烯利+150 mg/kg多效唑混合液和土施多效唑每株4 g处理控冲梢效果都显著高于对照,冲梢率分别是10.5%和7.6%,在花穗小叶处于展叶期虹吸输300 mg/kg乙烯利防控龙眼冲梢有效且安全。     

An appraisal of the use of reciprocal transfer experiments: assessing the stages of photoperiod sensitivity in chrysanthemum cv. Snowdon (Chrysanthemum morifolium Ramat.)

Reciprocal transfer experiments can be used to describe the stages of photoperiod sensitivity in day-length-sensitive plants. However, there are inconsistencies in the literature concerning the techniques used and, more importantly, the assumptions made when analysing such data sets. This paper appraises the use of reciprocal transfer experiments, with chrysanthemum as a model (short day) plant.Experiments showed little evidence to suggest that axillary meristems were incapable of responding to a floral stimulus when released from apical dominance by pinching (even though the apex appeared vegetative). Five short days given after pinching resulted in sufficient induction to initiate an inflorescence, although seven short days were required to commit a plant to flower with a leaf number similar to plants grown in continuous short days. Floral initiation was then visible at the apex after nine short days. Once the inflorescence had been initiated, long days delayed the early stages of flower development.The results are discussed with reference to reciprocal transfer experiments in general, and specifically in relation to problems that arise when the length of a 'juvenile' phase is confounded with the number of inductive cycles for flower commitment.     

铁线莲属植物的引种栽培研究初报

对部分铁线莲属（Clematis L.)植物进行了引种和栽培,根据花枝的着生情况把铁线莲分为3组。通过对野生种Cl.ranunculoides去年采收的种子进行有性繁殖,结果表明进行春化处理后播种的种子萌发率最高,达71％。对最适合在昆明生长的野生种Cl.ranunculoides和栽培品种Cl.montana‘Vera’进行扦插试验。结果表明Cl.montann ‘Vera’的生根率较高;扦插基质山沙优于珍珠岩;经NAA或IBA处理过的插条一根数多于对照。对栽培土壤进行了分析,结果表明大部分铁线莲也可在偏酸性土壤中生长。     

穗花牡荆花芽分化过程中形态和生理指标变化

以穗花牡荆为研究材料,通过探究其花芽分化进程和生理特性,为花期调控技术提供成花机理。采用物候期观察和石蜡切片相结合的方法并测定花芽分化过程中相关生理指标,研究花发育过程中的形态和生理变化。结果表明,穗花牡荆花芽分化为一年多次分化型,其进程可划分为七个时期：未分化期、总轴花序原基分化期、初级分轴花序原基分化期、次级分轴花序原基分化期、小花原基分化期、花器官分化前期和花器官分化后期。同一植株不同位置花芽及同一花序中不同单花分化的进程不同,第一季花期后各阶段的花芽分化形态常存在重叠。花芽分化过程中不同时期叶片和花芽的可溶性糖和可溶性蛋白质含量均有上升下降的变化,总体上叶片中营养物质含量高于花芽保证营养供应。花芽分化过程中,IAA、ABA、CTK和GA3整体水平上先升后降有利于花芽分化进行。研究认为,花芽中大量的可溶性糖和蛋白质积累及较高的碳氮比,有利于穗花牡荆花芽形态分化顺利完成。低水平的GA3/ABA和IAA/CTK有利于花序的形成,ABA/CTK和ABA/IAA比值升高促进小花原基和小花萼片原基的分化, GA3/CTK、GA3/ABA和GA3/IAA比值升高促进花瓣原基、雄雌蕊原基发育。     

内蒙古扁蓿豆种质资源花性状的变异分析

采用形态学标记的方法,对来源于内蒙古7个不同生态区的49份扁蓿豆（Medicago ruthenica L.）野生材料进行了花性状变异分析。对花萼长、花萼直径等12个性状进行系统调查和遗传多样性分析。结果表明：扁蓿豆材料间花性状的变异系数幅度最大的为花序长,其变异系数高达79.12%,变异幅度最小的为花萼直径, 其变异系数为3.82%;主成分分析表明,花性状中前7个主成分反应了总信息量的85.465％, 花序长、花序轴长、花冠长度、花序结荚数、花序种子数、花色和小花柄长等7个性状是造成扁蓿豆花性状变异的主要因素;相关分析表明,花性状间多数呈差异显著或极显著,例如:花序结荚数与花序种子数差异极显著,为0.811,呈显著正相关,而花序轴长和小花柄长差异极显著,呈显著负相关,为-0.340;聚类分析将49份材料分为6类, 花性状变异性相同或地理来源相同与相近的材料大部分聚在一起。说明：扁蓿豆材料间的花性状具有丰富的遗传多样性     

Temperature during the day, but not during the night, controls flowering of Phalaenopsis orchids

Phalaenopsis orchids are among the most valuable potted flowering crops commercially produced throughout the world because of their long flower life and ease of crop scheduling to meet specific market dates. During commercial production, Phalaenopsis are usually grown at an air temperature > or =28 degrees C to inhibit flower initiation, and a cooler night than day temperature regimen (e.g. 25/20 degrees C day/night) is used to induce flowering. However, the specific effect of day and night temperature on flower initiation has not been well described, and the reported requirement for a diurnal temperature fluctuation to elicit flowering is unclear. Two Phalaenopsis clones were grown in glass greenhouse compartments with constant temperature set points of 14, 17, 20, 23, 26, or 29 degrees C and fluctuating day/night (12 h/12 h) temperatures of 20/14, 23/17, 26/14, 26/20, 29/17, or 29/23 degrees C. The photoperiod was 12 h, and the maximum irradiance was controlled to < or =150 micromol m(-2) s(-1). After 20 weeks, > or =80% of plants of both clones had a visible inflorescence when grown at constant 14, 17, 20, or 23 degrees C and at fluctuating day/night temperatures of 20/14 degrees C or 23/17 degrees C. None of the plants were reproductive within 20 weeks when grown at a constant 29 degrees C or at 29/17 degrees C or 29/23 degrees C day/night temperature regimens. The number of inflorescences per plant and the number of flower buds on the first inflorescence were greatest when the average daily temperature was 14 degrees C or 17 degrees C. These results indicate that a day/night fluctuation in temperature is not required for inflorescence initiation in these two Phalaenopsis clones. Furthermore, the inhibition of flowering when the day temperature was 29 degrees C and the night temperature was 17 degrees C or 23 degrees C suggests that a warm day temperature inhibits flower initiation in Phalaenopsis.     

Determination for inflorescence development is a stable state,separable from determination for flower development in Pisum sativum L. buds

Terminal meristems of Pisum sativum (garden pea) transit from vegetative to inflorescence development, and begin producing floral axillary meristems. Determination for inflorescence development was assessed by culturing excised buds and meristems. The first node of floral initiation (NFI) for bud expiants developing in culture and for adventitious shoots forming on cultured meristems was compared with the NFI of intact control buds. When terminal buds having eight leaf primordia were excised from plants of different ages (i.e., number of unfolded leaves) and cultured on 6-benzylaminopurine and kinetin-supplemented medium, the NFI was a function of the age of the source plant. By age 3, all terminal buds were determined for inflorescence development. Determination occurred at least eight nodes before the first axillary flower was initiated. Thus, the axillary meristems contributing to the inflorescence had not formed at the time the bud was explanted. Similar results were obtained for cultured axillary buds. In addition, meristems excised without leaf primordia from axillary buds three nodes above the cotyledons of age-3 plants gave rise to adventitious buds with an NFI of 8.3 ±0.3 nodes. In contrast seed-derived plants had an NFI of 16.5 ±0.2. Thus cells within the meristem were determined for inflorescence development. These findings indicate that determination for inflorescence development in P. sativum is a stable developmental state, separable from determination for flower development, and occurring prior to initiation of the inflorescence at the level of meristems.     

花叶千年木花序梗愈伤组织直接再生花芽的初步研究

在离体条件下,诱导愈伤组织或外植体直接再生花芽已经在许多草本植物上取得成功［１～７］,而就木本植物来说,迄今尚未见到成功的报导。诱导愈伤组织或外植体直接再生花芽所形成的离体培养实验系统将十分有利于研究雌、雄性器官分化和发育所必需的条件［８］和找到所需...     

Invertase Activity, Soluble Carbohydrates and Inflorescence Development in the Tomato (Lycopersicon esculentum Mill.)

The concentration of reducing sugars in the developing firstinflorescence of the tomato (Lycopersicon esculentum Mill.)increased steadily between the macroscopic appearance of theflower buds and the initial stages of fruit expansion. Overthis period sucrose concentrations remained relatively constant.The rise in reducing sugar concentration was accompanied byan increase in the activity of an acid invertase. In individualflower buds invertase activity rose to a maximum shortly beforeanthesis and declined sharply as the anthers dehisced. Increased planting densities and removal of source leaves reducedthe rate of dry matter accumulation by the first inflorescenceand increased the incidence of flower bud abortion. These changeswere correlated with reductions in reducing sugar concentrations,in reducing sugar/sucrose ratios and in acid invertase levels.Removal of young leaves at the shoot apex significantly increasedthe relative growth rate of the inflorescence and led to a substantialincrease in its invertase content. These treatments had relativelylittle effect on sucrose concentration in the inflorescence. The data are consistent with the operation of an invertase-mediatedunloading mechanism for transported sucrose at sinks in theflower buds. It is suggested that the retarded development ofthe first inflorescence and the high incidence of flower budabortion observed under conditions of reduced photoassimilateavailability are causally related to the decline in invertaseproduction in the flower buds. Possible mechanisms for the regulationof invertase synthesis in the flowers are discussed. Lycopersicon esculentum Mill, tomato, inflorescence development, invertase, sink activity     

Erratum

The number of nodes produced by a bud meristem before differentiation into a flower is defined as its developmental potential. Decapitation, rooting, and grafting experiments were used to measure the developmental potential of the vegetative axillary bud meristems on Nicotiana tabacum. Decapitation experiments measure the in situ developmental potential while rooting and grafting experiments measure developmental potential in isolation and at a new location on the organism, respectively. A rooted or grafted bud exhibits one of two patterns of development: (1) It develops like an in situ bud or (2) It develops according to its new environment. For example, second axillary buds below the inflorescence produced 18.8 ± 0.8 nodes in situ, 17.9 ± 0.9 or 39.8 ± 1.1 nodes when rooted, and 22.2 ± 0.6 or 34.2 ± 0.7 nodes when grafted to the base of the plant. These results suggest that the buds which develop like in situ buds are developmentally determined while buds that develop according to their new environment are undetermined. On an individual plant, determined and undetermined buds are separated by one internode and only first, second, and third buds below the inflorescence exhibit determination.     

盐胁迫对Bt棉棉蕾杀虫蛋白表达的影响

为探讨土壤盐分对转Bt基因抗虫棉棉蕾抗虫性的影响程度,采用盆栽试验,以2个Bt棉品种‘新棉33B’(盐敏感)和‘中07’(耐盐)为试验材料,设置5个土壤盐分水平(0、0.15%、0.30%、0.45%和0.60%), 研究盐分对蕾期Bt棉棉蕾中杀虫蛋白含量、Bt基因相对表达量及氮代谢相关酶和物质代谢的影响.结果表明: 棉蕾中Bt杀虫蛋白含量随土壤盐分的升高而降低,与对照相比(0%),2个不同类型棉花品种在土壤盐分0.30%及以上时,棉蕾中杀虫蛋白含量显著下降,且随土壤盐分水平的升高,Bt 杀虫蛋白含量下降幅度增大.土壤盐分胁迫提高了棉蕾中Bt基因的相对表达量.在相同土壤盐分水平下,盐敏感品种棉蕾中Bt杀虫蛋白含量受土壤盐分影响较大.杀虫蛋白表达量下降幅度大的品种,其可溶性蛋白含量、谷氨酸丙酮酸转氨酶(GPT)和谷氨酸草酰乙酸转氨酶(GOT)活性下降幅度较大,游离氨基酸含量、蛋白酶和肽酶活性上升幅度也较高.说明土壤盐分胁迫下,Bt棉棉蕾蛋白质合成能力下降,分解能力增强,可能是导致杀虫蛋白表达量下降的主要原因.