几个决明属牧草在亚热带丘陵红壤的个体与群体生长特性

从引进的40个决明属牧草品系中选出代表性品系观测其生长表现,结果表明决明品种均表现为出苗率低、出苗时间长、种子成熟度低,营养含量差异较小。个体与群体生长研究结果表明,ATF2228品系为匍匐型、早熟品种,生物量低;ATF2217和ATF2219为直立型、中早熟品种,种子产量高、生物量大、再生能力较差,适于1年1次刈割利用;CPI92985的品种特性与CPI34721相类似,都是半匍匐型、中早熟品种,但CPI92985的生物量、种子产量、茎叶营养含量及刈割后再生能力好于CPI34721;CPI86134和CPI86172为半匍匐型、迟熟品种,冠高和生物量均大于CPI92985和CPI34721。另外,施肥可以显著提高CPI86134的生物产量和刈后再生能力,达到1年3～4次刈割利用,值得进一步研究。     

套种牧草果园土壤浸提液对萝卜种子发芽和幼苗生长的化感效应

采用生物检测方法,探讨果园套种牧草,其土壤浸提液对萝卜种子发芽和幼苗生长的化感效应。结果表明:果园分别全园套种宽叶雀稗、百喜草、平托花生、圆叶决明4种牧草,其土壤浸提液均对受体萝卜种子萌发有抑制作用,而对受体萝卜根的生长有不同程度的促进作用;全园套种百喜草处理对受体萝卜根干重起抑制作用;全园套种百喜草、平托花生、圆叶决明处理对受体萝卜的幼苗生长和干重均起显著的促进作用,而全园套种宽叶雀稗处理则反之;全园套种百喜草、平托花生、圆叶决明3种牧草处理对受体萝卜的化感综合效应指数均大于套种宽叶雀稗处理,且前者起促进作用,而后者起抑制作用;用不同牧草区土壤浸提液进行砂培法培养的萝卜幼苗根系活力受到极显著抑制,对照处理的萝卜根系活力最强,为156.3μg·g-1·h-1,而宽叶雀稗处理区的根系活力最小,为64.3μg·g-1·h-1。     

60Co-γ射线辐照处理对决明若干生长特性的影响

利用^60℃o-γ射线（辐照剂量为300 Gy,剂量率为4.687 5 Gy/min）辐照豆科决明属5个牧草品种的种子,通过盆栽收集各个品种的M1代种子,然后进行M2代试验与观察.结果表明,辐照后5个决明M2代的种子出苗率、植株的茎长、叶宽均无显著差异;34721号决明植株冠高有显著增长、2219号决明茎径有显著增长、86134号决明分枝数有极显著增长,92985号决明分枝数则有显著降低、86134号决明叶数和地上部植株干重有显著增长、2219号决明叶长增长显著,其余参试品种则无显著差异.植株的营养成分测定表明：仅2219号决明K含量呈显著下降、其他品种的N,P,K含量则无显著差异;2219不仅氨基酸总量呈显著下降、而且17种氨基酸都表现为不同程度的下降,86134氨基酸总量有显著增长、同时17种氨基酸都表现为不同程度的增长,而其余3个参试品种都无显著差异.经^60Co-γ射线辐照处理后的34721,86134,92985的酯酶同工酶谱与相应的对照有明显差别.生长观察结果表明,参试的5个决明品种M2代植株生长的现蕾期、初花期、盛花期、初荚期、盛荚期、成熟期表现为双向性,既有提早,也有推迟.     

艾蒿对大豆种子萌发和根系生长的化感作用研究

采用不同浓度(0,12.5,25.0,50.0 g·L~(-1))的艾蒿水浸提液处理5个大豆品种鹤丰、辽鲜、沪宁、毛豆29-2和韩国-45,通过测定发芽率、发芽势、发芽指数、主根长、根毛区宽度和根毛密度等指标,研究了艾蒿对不同品种大豆种子萌发和根系生长的化感作用。结果表明:艾蒿水浸提液对大豆化感效应的总体趋势为浸提液浓度越高,对大豆种子萌发和根系分化的抑制作用越强,且艾蒿对大豆生长的化感作用大小与品种有关,大豆不同品种对艾蒿化感作用的敏感程度不同,5个供试品种以鹤丰最不敏感,而毛豆29-2和韩国-45较为敏感。此外,大豆各发芽和根系生长指标对艾蒿的敏感程度也不同,以发芽势和根毛区宽度对艾蒿较为敏感,可以作为衡量艾蒿对大豆化感作用的品种评价指标。     

大豆根系浸提液对茎瘤芥种子萌发和幼苗生长的化感作用

采用室内生物测定方法,研究了不同质量浓度的大豆根系浸提液(10,20,40,80 g·L~(-1))对3个茎瘤芥品种(永安小叶、涪杂2号和涪杂5号)种子萌发和幼苗生长的化感作用。结果表明:大豆根系浸提液对茎瘤芥具有明显的化感效应,包括促进、抑制和"低促高抑"3种化感作用类型,并具有品种效应和浓度效应。不同浓度的大豆根系浸提液对永安小叶和涪杂2号种子萌发的影响表现为促进作用,而对涪杂5号种子萌发则表现为"低促高抑"的规律;对涪杂2号幼苗根长为抑制作用,但对永安小叶和涪杂5号幼苗根长则呈"低促高抑"的规律;对3个茎瘤芥品种的幼苗苗高和生物量具有促进作用,且随着浸提液浓度的升高而增强。从综合化感效应来看,大豆根系浸提液对3个茎瘤芥品种总体上为促进作用,且对永安小叶的促进作用最大。因此,永安小叶是大豆最佳的接茬品种。     

决明属牧草在闽东红壤山地的适应性

本文对决明属（Chamaecrista spp.)牧草9个品系的出苗、生长生育特性、物候期、鲜草及种子产量和5个品系的收割及再生性能进行为期2年的观测。结果表明：AFT2217、AFT2219、CPI92985等3个品系，在出苗率、生长状况、鲜草及种子产量等方面表现较好：刈割后的再生性能以CPI186134、CPI86178、CPI92985、AFT2217等4个品系为较强：至40cm高收割处理是相对较佳的刈割方式。     

大蒜鳞茎浸提液对大豆种子萌发和幼苗生长的化感效应

为探明大蒜鳞茎浸提液对大豆种子萌发和幼苗生长的化感作用,通过对大豆种子进行不同质量浓度(0,20,40,80,100 g·L^-1)大蒜鳞茎浸提液的处理,测定不同处理的发芽率、发芽势、发芽指数、根长、下胚轴长、植株鲜重、SOD活性、POD活性、CAT活性和MDA含量,并计算化感觉效应指数以及综合化感效应,探明大蒜鳞茎浸提液对大豆的化感效应。结果表明:大蒜鳞茎浸提液对大豆种子萌发及幼苗生长呈现低浓度促进、高浓度抑制的双重化感效应。浸提液质量浓度为20~40 g·L^-1时,对大豆种子萌发及幼苗生长具有一定的促进作用,SOD和CAT活性显著上升,MDA含量变化不大;浸提液质量浓度为80~100 g·L^-1时,对大豆种子和幼苗表现出明显的抑制作用,SOD和POD活性开始下降,MDA含量显著增加。此外,大豆种子萌发及幼苗生长的各项指标对大蒜化感物质的敏感程度不同,以对根长的化感作用较为敏感,可作为衡量大蒜对大豆化感作用的评价指标。     

化感水稻内生真菌的分离鉴定及其发酵产物的生物学效应研究

以化感水稻品种‘PI312777’‘6173’和‘6180’为研究对象,从水稻根、茎和叶中分离获得70株内生真菌,采用形态学观察和rDNA-ITS区序列分析,对内生真菌进行分类鉴定。进一步以化感水稻‘PI312777’分离得到的粘红酵母和塔宾曲霉为试验菌株,通过不同稀释倍数的真菌发酵液对非化感水稻进行MS半固体培养基育苗试验,研究化感水稻内生真菌发酵产物对非化感水稻萌发率、株高等形态指标及苯丙氨酸解氨酶（PAL）、过氧化氢酶（CAT）和过氧化物酶（POD）活性的影响。结果表明,从供试化感水稻品种中共分离得到17种内生真菌,经rDNA-ITS系统发育树分析鉴定为10个属,这些内生真菌主要分布在曲霉属（Aspergillus）（29.63%）、青霉属（Penicillium）（16.67%）和镰刀菌属（Fusarium）（12.96%）。不同稀释浓度塔宾曲霉发酵液对水稻幼苗生长均有促生作用,其中50倍稀释浓度处理可显著提高水稻幼苗的株高、根长及POD酶活性。粘红酵母菌发酵液5倍稀释浓度可显著提高水稻幼苗的PAL酶活性并对水稻幼苗有促生作用。稗稻共生条件下,塔宾曲霉和粘红酵母发酵稀释液对水稻均有促生效应。本研究可为化感水稻内生真菌进一步应用于水稻生产实践提供有益指导。     

圆叶牵牛对小麦种子的化感作用研究

为了给入侵杂草圆叶牵牛的综合治理提供参考依据,采用生物测定法研究了圆叶牵牛水浸提液对三个小麦品种种子萌发和幼苗生长的影响。结果表明,圆叶牵牛内存在化感物质,浸提液处理降低了三个供试小麦品种的发芽率、根长、苗高、活力指数,抑制作用随浓度的升高而增强。小麦幼苗生长对浸提液反应更为敏感,浸提液对幼苗生长的抑制作用大于对种子萌发的抑制作用。相同浓度的浸提液对三个小麦品种的影响程度存在差异,石麦18抗性较强。     

山药化感物质对山药和玉米种子萌发及幼苗生长的影响

本研究以山药零余子和玉米种子为受体材料,采用生物测试方法,以发芽率、发芽势、发芽指数、根长、茎长和干重为种子萌发和幼苗生长参数,研究山药植株腐解液、根系分泌物和根际土浸提液对受体材料的化感效应,旨在探明山药化感物质的释放途径,探索山药化感物质对不同受体材料的化感作用,为揭示山药连作障碍的机理奠定基础。结果表明：山药植株腐解液和根系分泌物对山药和玉米均有强烈的化感抑制作用,根际土浸提液的化感作用较微弱,化感作用强度为根系分泌物˃植株腐解液˃根际土浸提液,山药根系分泌物和植株腐解液含有丰富的化感物质,可能是山药自毒物质的主要来源之一,是山药化感物质研究的可靠基础材料;在试验设置的浓度范围内,山药化感物质对受体材料的抑制作用与其质量浓度呈正比,3种浸提液对受试材料的化感作用存在低促高抑的浓度效应,低于100 mg/mL时有微弱的促进作用,大于等于100 mg/mL就会产生强烈的抑制作用,随着浓度升高,化感抑制作用强度越大;山药的化感物质对玉米幼苗生长抑制强度大于种子萌发期,山药则相反;结合种子萌发和幼苗生长的综合化感效应指数,2种受试作物对山药化感作用的敏感程度为自毒作用强于他感作用。     

Relationship Between Allelopathic Effects and Functional Traits of Different Allelopathic Potential Rice Accessions at Different Growth Stages

In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions at different growth stages were analyzed.The main results were as follows:Allelopathic responses to temperature and light varied with different allelopathic potential rice accessions at different growth stages.With the rise of temperature and the extension of photoperiod,allelopathic effect increased firstly and then decreased at 2–3 leaf stage,but increased constantly at the 4–5 and 7–8 leaf stages in strong allelopathic rice accessions[O.longistaminata,F1(O.longistaminata×RD23),F2(RL159 and RL169)].Temperature had significant impact on allelopathic effect without considering light factors,but light showed little effect on rice allelopathy at the same temperature conditions.The greatest allelopathic effect was attained with moderate temperature and long photoperiod at 2–3 leaf stage in strong allelopathic rice accessions,but all the rice accessions showed weak allelopathic effects at the low temperature condition(15oC/10oC),and the influence of different factors on allelopathy followed a general trend as temperatureleaf stagelight,indicating that among the multiple factors impacting rice allelopathy,temperature was the main factor.Allelopathic characteristics of F1 and F2 to various temperature and light were similar to O.longistaminata,showing that allelopathic genes from wild rice can be expressed in its descendants.Temperature and light also had significant effects on SLA and SMF,and rice allelopathy was closely correlative to SLA in strong allelopathic rice accessions at the 4–5 and 7–8 leaf stages,but there was no correlation between rice allelopathy and SMF at different growth stages.These results suggested that rice adjust the relationship between allelopathy and SLA and adapt to the varied environments,and that high temperature and long photoperiod can enhance rice allelopathic activity.     

温度对不同叶龄长雄野生稻及其后代化感作用的影响

掌握温度对长雄野生稻(Oryza longistaminata)及其后代化感作用的影响,对开发利用野生种质资源的化感抗草基因具有重要意义。采用直接树脂吸收法收集不同叶龄长雄野生稻及其后代在各温度条件下的根系分泌物,并以稗草作为受体,测定其化感作用。结果表明:1)温度、叶龄和温度×叶龄对水稻化感作用的影响与其自身化感潜力正相关,且对强化感和中化感潜力水稻(OL、F1、RL159和RL169)的化感作用影响极显著,而对弱化感水稻(RD23和RL219)的化感作用影响不显著。2)供试条件下长雄野生稻及其后代根系分泌物对稗草的化感作用均为抑制作用,其中,低温不利于水稻化感潜力的发挥。15℃时,强和中化感潜力水稻在不同叶龄对稗草的苗高、根长和生物量的抑制作用最弱,化感综合效应指数也显著大于同等叶龄的高温处理。3)高温有利于水稻化感潜力的发挥,但并非总是随温度的升高而增强。在6叶期和8叶期,水稻材料OL、F1、RL159和RL169随温度的升高化感作用逐渐增强,但在2叶期和4叶期则表现为先增强后减弱,在25℃时对稗草化感作用最强。4)在15℃时,强和中等化感潜力水稻在2叶期化感作用最弱,而在其他温度条件下,其化感作用随叶龄的增加表现为先减弱后增强,在2叶期化感作用最强。研究结果显示,温度对不同叶龄的水稻化感作用具有调控作用,幼苗阶段高温有利于强和中化感潜力水稻化感作用的发挥。     

决明属牧草新品种的选育

通过有性杂交和辐射处理5个决明属牧草品种进行新品种选育研究。结果表明：圆叶决明种内杂交取得成功;圆叶决明和羽叶决明种间杂交,以圆叶决明为母本的杂交组合已有结荚后代;有性杂交筛选到6株农艺性状已基本稳定的生物量大、分枝多的杂交株系后代。辐射育种筛选到5个品质优良的新品系,其中2个86134品种辐射变异后．后代品系的茎长和生物量有明显提高,茎叶比则呈明显下降;2个92985品种辐射变异后,后代品系的粗蛋白含量有明显提高;1个34721品种辐射后,后代品系的Ca含量有明显提高。     

The influence of tall fescue on the germination, seedling growth and yield of birdsfoot trefoil

The influence of tall fescue ( Festuca arundinacea Schreb.) on germination and seedling growth of birdsfoot trefoil ( Lotus corniculatus L.) was evaluated during 1983-85 at Manhattan, Kansas. Studies were designed to evaluate tall fescue cv. Kentucky-31 for possible allelopathic compounds, determine the effects of tall fescue on the germination, seedling growth and yield of birdsfoot trefoil, and to characterize the chemical properties of tall fescue. Fescue produced allelopathic compounds, particularly during the spring and autumn months when it was actively growing. The greatest trefoil inhibition occurred with fescue plant extracts prepared during the autumn (September and October). The concentration of fescue extracts influenced trefoil germination, with greater inhibition as fescue concentration increased. In a sand medium under greenhouse conditions, fescue extracts prepared in spring and autumn reduced trefoil growth by 50 and 56%, respectively, with no inhibition during the summer months. Under field conditions, full strength fescue extracts reduced trefoil plant populations by 14 and 57% with spring and autumn prepared extracts, respectively. Fescue competition reduced sod-seeded trefoil plants per unit area by 17 and 31% for spring and autumn seeding, respectively. Full strength fescue extracts reduced trefoil seedling growth by an average of 37%, and trefoil dry matter yields by 53%.     

山蚂蝗属（Desmodium Desv.）营养期营养成分分析

对17份山蚂蝗材料营养期的营养成分进行测定与分析。结果表明:(1)粗蛋白含量最高的为CIAT3787(D.hererocarpum)(22.34%),其次是CIAT46562(D.dunniinicaraguense)(22.32%);粗纤维含量最高的是CIAT13218(D.velutinum)(38.70%),显著高于其他品系(p>0.05);(2)山蚂蝗营养成分之间存在不同程度的相关性,粗纤维含量分别与粗灰分、无氮浸出物、磷的含量存在极显著负相关,粗灰分含量与磷含量有极显著正相关,与钙含量有显著相关;(3)通过聚类分析,在欧氏距离8.0处,可将17份供试山蚂蝗材料划分为3类,其中CIAT46562和CPI46561(D.incanum)单独聚为一类。     

The heterotoxicity of Hordeum vulgare L. extracts in four growth stages on germination and seedlings growth of Avena ludoviciana

Phytotoxicity of barley extracts (Hordeum vulgare L.) on wild oat (Avena ludoviciana Durieu) was investigated. Water extracts five varieties of barley were bioassayed on germination and seedling growth of wild-oat to test the heterotoxicity of barley on wild-oat, study the dynamics of allelopathic potential over four growth stages and identify the most allelopathic plant part of barley in each stage. Whole barley plants were extracted at growth stage 4 (stems not developed enough), whilst for the following growth stages roots, stems, panicles and leaves were extracted separately. Seedling growth bioassays demonstrated that the wild-oat responded differently to the allelopathic potential of barley. For wild-oat radical growth and coleoptile growth were more depressed than germination, though. The allelopathic potential of barley plant parts was not stable over its life cycle for wild-oat. Leaves and stems were the most phytotoxic barley plant parts for wild-oat in the all stages. Among the varieties Eizeh appeared as the best one showing toxicity to seed germination of wild oat at its stage 4 and 8. Results suggested that the response by wild-oat varied depending on the source of allelochemicals (plant part) and the growth stage of the barley plant and kind of variety. The results leaded to conclude that Eizeh variety of barley was good to grow as it has good check on seed germination of wild oat plants as well as it also retarded the growth of root and shoot length of oat.     

果园草被残体浸提液对日本草种子发芽与幼苗生长的化感效应

采用生物检测方法，研究果园草被植株残体浸提液处理后的日本草种子萌发和幼苗生长的变化。结果表明：（1）10％浓度浸提液处理果园土壤时，会影响果园杂草的萌发及优势种日本草根冠比；（2）用不同浓度果园草被的植株残体浸提液砂培日本草种子时，都会降低发芽势和发芽率，且竹节草处理的效果最明显，达到差异显著（p<0.05）或极显著水平（p<0.01）；（3）百喜草处理促进日本草幼苗生长，宽叶雀稗处理效果相反；竹节草处理5.0％和10.0％时抑制日本草根生长，而其它处理促进了日本草根生长；（4）不同处理的日本草生物量都不同程度地小于对照，且竹节草处理的效果最明显，达到差异显著或极显著水平；（5）各处理对受体日本草的化感综合效应指数都小于对照，起抑制作用，竹节草处理抑制效果最明显。     

玉米马铃薯地上部水浸提液对玉米生长的影响

采用盆栽试验,分析玉米间作马铃薯体系中两种作物不同生育时期活体植株地上部水浸提液对玉米生长发育的影响,探讨两种作物地上部水浸提液对玉米的化感效应。结果表明,马铃薯地上部水浸提液对玉米干物重的化感效应强于玉米地上部水浸提液。马铃薯地上部水浸提液对生育期内玉米的株高、茎粗、叶面积均有显著促进作用,对茎、叶干物重有先弱后强的促进作用,对根干物重有先强后弱的促进作用。玉米地上部水浸提液对灌浆期前的玉米株高、茎粗、叶面积均有显著促进作用,对茎、叶和根干物重均有不同程度的促进作用;对灌浆期后的玉米株高、茎粗、叶面积无显著影响,玉米茎和根干物重有抑制作用。马铃薯地上部水浸提液处理的玉米穗干重显著高于玉米水浸提液和水处理,在灌浆期分别高出其90.21%和144.60%,到成熟期分别高出110.98%和151.90%,表明在玉米间作马铃薯体系中,马铃薯地上部对玉米经济产量有显著影响。