蜀葵水浸液对两种杂草种子萌发的化感效应

应用室内培养皿生物测定方法,研究了蜀葵浸提液对藜和反枝苋种子萌发和根生长的影响.结果表明:蜀葵浸提液能抑制种子萌发,随着浸提液浓度的升高,其抑制效果越明显,且化感效应的强度在不同部位存在差异.蜀葵叶的水浸液在0.25、0.062 5 g/ml时,对反枝苋根生长的抑制率分别为-50.13％、- 1.32％,表现为促进作用.蜀葵茎的水浸液对根的生长既有抑制作用,也有促进作用,在蜀葵茎水浸液的浓度为0.025、0.062 5、0.125 g/ml时,对反枝苋根生长的抑制率分别为- 29％、-2.11％、-35.6％;对藜根生长的抑制率分别为-34.11％、-23.13％、-26.27％,均表现为促进作用;在浓度为0.4、0.5g/ml时,反枝苋根生长呈化感作用浓度效应,而藜在浓度为0.4 g/ml时根生长没有受到影响.     

黄花蒿对绿豆种子萌发及幼苗生长的化感效应

以绿豆种子为受体,采用室内生测法,探讨黄花蒿不同部位水浸提液对绿豆种子的萌发率、幼苗生长及叶绿素含量的影响。结果表明:黄花蒿各部位(根、茎、叶)水浸提液随处理浓度增加,对绿豆的化感效应增强,对种子萌发的抑制强弱为:叶>茎>根,且随处理浓度升高,发芽率降低;对幼苗的根系生长表现为低浓度(20mg/mL根、茎水浸提液)促进,当浓度高达40mg/mL均有明显抑制作用;幼苗高度总体降低,最高降幅分别为46.29%,47.67%和56.48%;叶绿素a和叶绿素b的含量也不同程度减少。可见黄花蒿影响绿豆种子萌发及幼苗生长,因此大面积栽培黄花蒿或绿豆种植应考虑黄花蒿的化感效应。     

刺槐根际土壤水浸提液对5种常见园林植物种子萌发及幼苗生长的化感作用

为了探讨刺槐的化感作用,以5年树龄的刺槐根际土壤为试材,采用化感隶属值累加值综合评价化感效应,研究不同浓度土壤水浸提液对一串红(Salvia splendens Ker-Gawler)、高羊茅(Festuca elata)、红豆草(Onobrychis viciaefolia Scop)、结缕草(Zoysia japonica Steud.)、鸡冠花(Celosia cristata L.)种子萌发、幼苗生长及生理指标的影响。结果表明,随着浸提液浓度的升高,5种园林植物的发芽率、发芽势、发芽指数、叶绿素含量、株高、茎粗及总干重逐渐降低;相对电导率和MDA含量逐渐升高;POD、SOD和CAT活性先升高后降低;土壤水浸提液对5种园林植物的综合化感效应表现为化感抑制,抑制程度由轻到重依次为高羊茅、结缕草、鸡冠花、一串红和红豆草。     

火炬树果穗水浸提液对小麦种子萌发的化感效应

研究了不同浓度(10%、5%、2.5%和1.7%)的火炬树(Rhus typhina)果穗水浸提液对小麦种子萌发的化感作用.结果表明,火炬树果穗水浸提液对小麦种子的萌发具有强烈的抑制作用.1.7%、2.5%、5%和10%的火炬树果穗水浸提液处理的小麦种子萌发率从对照(蒸馏水处理)的98.9%分别降到81.1%、74.4%、46.7%和26.7%,萌发率、萌发指数和幼苗活力指数均显著低于对照(P＜0.05),而且萌发进程延迟.火炬树果穗水浸提液对萌发指数的化感效应最强,对幼苗活力指数的化感效应次之,对萌发速率系数的化感效应最弱.     

火炬树根和凋落叶水浸提液对小麦种子萌发的化感作用

研究了不同浓度(10%、5%、2.5%和1.7%)的火炬树(Rhus typhina)根和凋落叶水浸提液对小麦种子萌发的化感作用.结果表明:2种器官水浸提液对小麦种子萌发均具有强烈的化感抑制作用,表现为萌发率、萌发指数、幼苗活力指数的降低和萌发进程的延迟(萌发速率系数增大),而且具有明显的浓度作用:火炬树凋落叶水浸提液对小麦种子萌发的化感作用强于根的化感作用;火炬树根和凋落叶水浸提液对小麦种子萌发指数的化感作用最强,对幼苗活力指数的化感作用次之,对萌发速率系数的化感作用最弱.     

火炬树水浸提液对玉米种子萌发的化感效应

研究了不同浓度(0.10、0.05、0.025 g/L)的火炬树(Rhus typhina)凋落叶和宿存果穗水浸提液对玉米种子萌发的化感作用.结果表明:2种器官水浸提液对玉米种子的萌发均具有强烈的抑制效应,不同浓度的水浸提液处理的种子萌发率、萌发指数和幼苗活力指数均显著低于对照,而且萌发进程延迟.凋落叶水浸提液对玉米种子萌发的化感效应强于果穗水浸提液,两者均表现出明显的浓度效应.     

板栗叶水浸液对3种中药材种子萌发及幼苗生长的影响

选取商洛道地中药材桔梗、黄芩和丹参,研究不同浓度(0,5,10,20,30,40 mg/mL)板栗叶水浸液对3种受体中药材种子萌发和幼苗生长的影响.结果表明,低浓度板栗叶水浸液对3种中药材种子的萌发有明显的化感促进作用,但随着水浸液浓度的不断提高,其对受体种子的化感促进作用逐渐减弱并消失,开始表现为抑制作用.板栗叶水浸液在5～20 mg/mL浓度范围内对3种受体中药材种子的发芽率、发芽势、发芽指数、相对电导率、游离氨基酸含量、可溶性糖含量、可溶性蛋白含量以及幼苗根长、苗高均表现为化感促进作用,但超过其临界值就开始表现为化感抑制作用.其总体趋势呈“抛物线”形规律.板栗叶水浸液在试验浓度范围对桔梗、黄芩、丹参种子萌发和幼苗生长有一定的促进作用.     

玉米、小麦秸秆水浸提液对蔬菜种子的化感作用

以黄瓜、生菜、茄子种子为受试材料,采用室内生物测定方法研究了玉米、小麦秸秆水浸提液的化感作用.结果表明,作物秸秆对蔬菜种子的影响有抑制、促进、促进/抑制双重作用和无显著作用等多种形式.玉米水浸提液对黄瓜种子活力指数、幼苗根长和鲜质量显著抑制,对苗高和干质量表现低浓度促进高浓度抑制;对生菜、茄子种子的发芽和根系生长显著抑制,对苗高和鲜质量均表现促进/抑制双重作用.小麦秸秆水浸提液对黄瓜苗高、鲜质量表现促进作用;对生菜种子活力指数和幼苗根长具有显著抑制作用,对其苗高和鲜质量均表现促进/抑制双重作用;对茄子发芽率显著抑制作用,对其根长、苗高和鲜质量均表现双重作用.根据化感敏感指数,玉米秸秆水浸提液对受体蔬菜的化感作用强于小麦;生菜对秸秆浸提液最敏感,茄子次之,黄瓜最不敏感.     

蒙古栎枯叶水浸提液对二月兰的化感作用

为探究蒙古栎(Quercus mongolica)林下植被稀少的状况是否为枯叶产生的化感作用,以蒙古栎枯叶为供试材料,二月兰为受体材料,采用培养皿滤纸法研究不同浓度蒙古栎枯叶水浸提液对二月兰种子萌发及幼苗生长的影响.分别采用0.00、0.02、0.04、0.06、0.08和0.10 g/mL浓度的蒙古栎枯叶水浸提液培养...     

核桃叶水浸液对不同产地丹参种子的化感效应

以不同产地的丹参种子为材料,研究了不同浓度(0、0.005、0.01、0.02、0.03、0.04g/ml)核桃叶水浸液对丹参种子萌发和幼苗生长的影响.结果表明,低浓度(0.005、0.01、0.02 g/ml)的核桃叶浸提液对不同产地丹参种子的萌发有明显的化感促进作用;随着水浸液浓度的提升,其对受体的促进作用逐渐减弱、消失,甚至表现为抑制作用.在试验浓度范围内,核桃叶水浸液对丹参种子的幼苗根长、苗高、相对电导率、可溶性糖含量及可溶性蛋白含量均表现为促进作用,最佳作用浓度为0.02 g/ml.核桃叶水浸液可以在某种程度上促进丹参种子的萌发和幼苗的生长.     

Effect of Seed Size on Germination and Seedling Growth in Greengram (Vigna radiata L. Wilczek) and Blackgram (Vigna mungo L. Hepper) Cultivars

The effect of seed size on germination and seedling growth was assessed using cultivars of greengram and blackgram. Significant positive correlation was noticed between seed size and germination, seedling height, root length, primary leaf size and seedling weight. The possible advantages of choosing cultivars with heavier seeds for attaining better crop stand especially under rainfed situation are discussed.     

Allelopathic Effects of Parthenium hysterophorus Extracts on Seed Germination and Seedling Growth of Eragrostis tef

The present study was conducted to investigate the allelopathic effects of Parthenium hysterophorus weed on seed germination and seedling growth of tef. Flower, stem, root and leaf aqueous extracts of Parthenium at 0, 1, 5, and 10 % concentrations were applied to determine their effect on tef seed germination and seedling growth under laboratory conditions. Increasing concentrations of aqueous extracts of Parthenium from leaf and flower inhibited seed germination and complete failure of seed germination was recorded when the extract concentration from the leaf part was 10 %. In contrast, aqueous extracts from stem and root had no effect on tef seed germination. Roots appeared more sensitive to allelopathic effect than shoots. Extracts from flower, root and stem had a stimulatory effect on shoot length at all concentration levels, as against an inhibitory effect of leaf extracts. Root extracts at low concentration (1 %) greatly promoted root length but aqueous extracts from leaf and flower inhibited root length.     

皱叶酸模水提液对种子萌发和幼苗生长的影响

研究了不同浓度的皱叶酸模水提液(5,10,20,40 g/L)对3个蔬菜品种(小白菜、上海青、油麦菜)种子萌发、幼苗生长的化感作用。结果表明:皱叶酸模对蔬菜化感效应的总体趋势为:随着水提液浓度升高,对蔬菜生长的抑制作用越强;用20 g/L的浸提液处理,主要形态和生化指标都表明蔬菜的生长受到了显著抑制或破坏;在小于10 g/L的浓度范围内,皱叶酸模的化感作用能够提高低活力种子的萌发率,但降低了种子的发芽速度,且化感作用受受体品种差异和种子自身活力的影响而表现不一致;随着化感物质浓度升高,蔬菜幼苗生长受皱叶酸模化感作用的影响为:对根长的影响大于对苗高的影响。     

核桃醌对黄芩种子萌发和幼苗生长的影响

为探讨核桃和黄芩复合种植的可行性,本文通过室内盆栽试验的方法研究了核桃主要化感物质核桃醌溶液对黄芩种子萌发及幼苗生长的影响。试验结果表明：核桃醌对黄芩种子的萌发主要表现出抑制作用,随着浓度的升高,抑制作用逐渐增强;对幼苗生长的影响则受到核桃醌浓度和黄芩幼苗密度双因素的影响,在高浓度或高密度下表现出较强的抑制作用,在低浓度高密度下则表现出一定程度的促进作用,但此促进作用主要针对地上部分生物量,对具有较高药用价值的根部则表现出强烈的抑制作用,因此本文认为核桃和黄芩并不适宜采用林药复合种植模式。     

Effects of photoperiod and temperature on flowering in mungbean (Vigna radiata (L.) Wilczek)

Summary Forty strains of mungbeans, including all of the entries in the 1st and 2nd International Mungbean Nurseries (IMN), were grown in plant growth chambers in photoperiods of 12, 13, 14, 15, and 16 hours and mean temperatures of 18, 23, and 28°C. Results show that (1) mungbean strains differ in their flowering response to photoperiod and to mean temperature; (2) increasing the photoperiod of reducing the mean temperature delayed flowering, the amount of delay varied with the strain: (3) variations in mean temperature may alter the effect of the photoperiod on flowering in particular strains. Twenty-five strains which flowered in all photoperiod-temperature treatments could be divided into four groups, each group being successively later in flowering. The remaining 15 strains could be divided into four groups, according to their failure to flower within 105 days in specific photoperiod-temperature treatments. Flowering response in the growth chamber is useful in explaining flowering response in the 2nd IMN at three locations varying from 14°N to 49°N latitude.Contribution No 7516 from the Missouri Agricultural Experiment Station.     

不同施肥方式对鱼腥草生长发育及产量的影响

采用单因子随机区组设计，通过测定鱼腥草株高、分枝数和鲜重，分析了5种肥料对鱼腥草生长发育和产量的影响。结果表明，鱼腥草在种植初期生长较慢，施用有机肥有利于增加鱼腥草生长后期的株高和分枝数，其中以鸭粪和猪粪的作用最明显。施用有机肥对鱼腥草有增产作用，以中等施肥水平鸭粪的鱼腥草产量最高。增施有机肥量对鱼腥草地下部的增产作用高于化肥和常规肥。在鱼腥草人工栽培中，鱼腥草施肥宜选择鸭粪为主，与其它有机肥（人粪尿、猪粪）配合施用，并在植株生长前期和后期辅以少量速效化肥。在施肥水平上，人粪尿、猪粪、鸭粪、施用量依次以108000 kg/hm2，54000 kg/hm2，45000 kg/hm2为宜。     

小麦秸秆浸提液和腐解液对棉花种子发芽及幼苗生长的化感效应

于2014年在江苏南京江苏省农业科学院人工气候室内进行水培试验,以中棉所50为材料,设置5个小麦秸秆浸提液和腐解液含量(质量分数1.0%,3.0%,5.0%,7.0%和10.0%),研究小麦秸秆浸提液和腐解液对棉花种子萌发和根系发育的影响,明确小麦秸秆对棉花生长的化感效应。结果表明:随秸秆浸提液和腐解液含量升高,浸提液和腐解液中氮、磷、钾和总酚酸含量持续升高;相同含量下,腐解液中氮和磷含量与浸提液差异不显著,而钾和总酚酸含量高于浸提液。≤7.0%的浸提液和≤5.0%的腐解液只延迟了棉花种子发芽时间,并未影响发芽率;高于此含量时,两者不仅延迟发芽时间,而且降低发芽率。浸提液和腐解液含量高达3.0%后显著抑制棉花主根伸长、缩短侧根发生区、减少侧根数量、降低根系总表面积和总体积,并随含量增加,抑制和降低作用显著增强。低含量的小麦秸秆浸提液与腐解液显著促进根系呼吸速率和根系活力,当浸提液与腐解液含量高于3.0%时,根呼吸速率与根活力显著降低,而MDA含量却随含量提高而显著增加。小麦秸秆浸提液和腐解液中总酚酸和养分含量与其化感效应有关,高含量的浸提液和腐解液抑制棉花种子萌发、根系形态指标建成和根系呼吸,同等浓度下,小麦秸秆腐解液对棉花的化感效应强于浸提液。     

Inheritance of seed phytate in mungbean (Vigna radiata (L.) Wilczek)

Phytic acid (PA) is the main storage organic form of phosphorus (P) in seeds of cereals and legumes. It is a strong inhibitor against the absorption of nutrients in monogastric animals. The objective of this study was to determine the variation of total P (TP) in seeds of mungbean germplasm and investigate the inheritance of seed P compound and phytate contents. TP content in seeds of 250 accessions were found to range from 2.34 to 5.75 mg/g. The inheritance was studied in the F₂ population derived from a cross between 2 accessions with the lowest and highest PA contents, viz. V1658BBR and V1141BG. Broad-sense heritability estimates of TP, inorganic P (IP), and phytate P (PhyP) contents were 80.8, 78.6 and 80.7%, respectively. The 9:7 segregation ratio of F₂ population in this study indicated that high TP and PhyP were controlled by dominant alleles at 2 independent loci of major genes showing duplicated recessive epistasis.     

云南松凋落叶浸提液对其种子萌发和幼苗生长的影响

以云南松种子为受体,研究了云南松凋落叶的水浸提液和乙醇浸提液对其种子萌发和幼苗生长的影响,从化感作用的角度探讨云南松天然林更新困难的成因。结果表明:云南松凋落叶水和乙醇浸提液对其种子萌发和幼苗生长均产生化感抑制作用(SEI<0),而且抑制强度随浸提液浓度的增加大致呈增强的趋势。研究结果表明,云南松凋落叶具有化感自毒作用,这也是导致云南松天然林更新困难的重要成因之一。