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1.
以普通红三叶种子为受体,采用培养皿滤纸法,初步研究了红三叶对6种不同浓度(0.025,0.05,0.075,0.10,0.15,0.20 g/mL)叶浸提液的化感响应.结果表明,红三叶的叶浸提液对其种子的发育具有不同程度的化感影响.红三叶不同浓度的叶浸提液对种子发芽势表现出"低促高抑"的浓度效应,而对发芽率表现出一定的抑制作用;红三叶不同浓度的叶浸提液对胚根长具有极强的抑制作用(p<0.01),而对下胚轴长既具有抑制作用又有促进作用,且在一定浓度范围内表现出"低促高抑"的现象. 相似文献
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以红三叶种子为受体,对比研究了扁穗牛鞭草根、茎和叶水浸液,不同处理浓度的化感作用.结果表明:扁穗牛鞭草根、茎和叶水浸液对红三叶种子萌发和幼苗生长较对照均表现出相同的趋势,即随着水浸液浓度的增加,4个所测指标所受的抑制作用均有所增强,而在相同的处理浓度下,红三叶种子萌发及幼苗生长对扁穗牛鞭草不同部位水浸液的敏感程度为叶最敏感,茎次之,根最不敏感.与对照相比,所有部位的扁穗牛鞭草水浸液对红三叶幼苗根系相对电导率和丙二醛含量均呈递增趋势,而对抗氧化酶(POD、SOD、ASA-POD)活性均呈递减趋势,并且在同一浓度下,扁穗牛鞭草水浸液对红三叶幼苗根系生理指标的影响强度顺序也为叶>茎>根. 相似文献
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51份红三叶种质资源萌发期耐铜性评价 总被引:1,自引:0,他引:1
为筛选耐铜性红三叶种质资源,建立萌发期耐铜性评价体系,对51份红三叶种质资源进行100 mg·L-1 Cu2+浓度胁迫和去离子水对照的发芽试验,对红三叶种质资源的发芽指标和根系指标进行统计学分析。结果发现:100 mg·L-1 Cu2+胁迫对红三叶萌发指标和根长有显著抑制作用,但促进根系增粗;Cu2+胁迫下不同红三叶品种的各萌发指标间存在较大差异。根据各指标的相关性分析和主成分分析,筛选出相对发芽率、相对活力指数、相对总根长等3项指标为红三叶耐铜性评价指标。通过加权隶属函数评价和聚类分析发现,51份红三叶种质资源耐铜性可分3个类群,其中CF 022176、CF 022187、CF 022236、CF 022170、CF 022171、CF 022167等6份耐铜性较强。 相似文献
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Endophyte Infection May Affect the Competitive Ability of Tall Fescue Grown with Red Clover 总被引:4,自引:0,他引:4
D. P. Malinowski D. P. Belesky J. M. Fedders 《Journal of Agronomy and Crop Science》1999,183(2):91-101
Cool-season grasses infected with Neotyphodium endophytes may be more persistent and competitive than non-infected plants. In a greenhouse experiment, two tall fescue ( Festuca arundinacea Schreb.) cloned genotypes (DN2 and DN11) with different growth characteristics and endophyte status (E−, non-infected; E+, infected) were grown in monocultures and in full competition with red clover ( Trifolium pratense L.) cv. Reddy Red for 20 weeks. When grown in monoculture, endophyte infection reduced the root dry matter (DM) of DN2 (16 %) and DN11 (5 %) when compared to E− plants, while shoot DM was not affected. In full competition with red clover, root and shoot DM of tall fescue were not influenced by endophytes, but cumulative herbage DM yield was less in E+ than in E− plants. Root growth of red clover was significantly depressed (22 %) in competition with E+ plants of DN2 compared to E− plants, but was not affected when plants were grown in competition with DN11. The relative yield total (RYT) did not differ from 1.0 in red clover mixtures with E− plants of DN2 and DN11, and with E+ plants of DN11, indicating competition between the competitors for the same resources. In contrast, RYT was less than 1.0 in the red clover/DN2 E+ mixture, suggesting a negative interaction between the competitors. Endophyte infection increased the competitive ability of DN2 but reduced that of DN11 when compared to E− plants. Because the concentration of pyrrolizidine alkaloids in roots of E+ plants of DN2 was twice that found in roots of DN11 (1083 and 536 μg g−1 , respectively), we suggest that pyrrolizidine alkaloids might influence the competitive ability of some endophyte–tall fescue associations through a possible allelopathic effect on companion species. 相似文献
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硒在红三叶草中的抗氧化生理 总被引:4,自引:0,他引:4
通过施硒土培,研究了不同的硒浓度对红三叶草抗氧化能力的影响。结果表明:当施硒浓度0 ̄5.0mg/kg(土壤)时,随着施硒浓度提高,体内还原性谷胱甘肽的含量和谷胱甘肽过氧化物酶的活性增加,SOD的活性增加,Vc含量增加,脂质过氧化产物丙二醛的含量降低,其抗氧化能力与施硒浓度呈正相关,提高了机体抗氧化水平和抗逆能力。 相似文献
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R. M. M. S. Thilakarathna Y. A. Papadopoulos S. A. E. Fillmore B. Prithiviraj 《Journal of Agronomy and Crop Science》2012,198(4):295-303
Red clover cultivars, including diploid and tetraploid, are commonly used in legume‐based pasture mixtures. However, information on nodulation under different starter N regimens is limited. We hypothesized that there is genetic variability among different red clover cultivars for nodulation. A root hair deformation assay was conducted using three diploid (AC Christie, Tapani and CRS15) and three tetraploid (Tempus, CRS18 and CRS39) red clover cultivars by inoculating them with Rhizobium leguminosarum biovar trifolii. Nodulation and morphological characteristics of two selected red clover cultivars, AC Christie and Tempus, were determined under five starter N concentrations (0, 0.2, 0.4, 0.8 and 1.6 mg per plant). Inoculation with rhizobia increased root hair deformation with significant interaction across cultivars. Nodulation was delayed under high starter N concentrations, and genotypic differences were evident for days‐to‐nodule initiation. There was a positive quadratic response to starter N for AC Christie and a negative quadratic response for Tempus for nodulation. Tempus had more active nodules (92 %) than AC Christie (73 %). The genetic variability of red clover cultivars should be considered in N fixation studies and their response to availability of initial N. 相似文献
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为探索磷素对不同大豆品种籽粒异黄酮含量的影响,寻找不同基因型大豆品种最佳施磷水平,以期提高大豆籽粒异黄酮的含量,改善其品质。选用‘黑农48’(高蛋白品种)、‘黑农37’(中间型品种)、‘黑农44’(高油品种)3个大豆品种作为试验材料。采用盆栽,在每kg土壤施N和K2O各为0.033 g基础上,设P1、P2、P3、P4 4个P处理(即每kg土壤分别施P2O5 0、0.033、0.067、0.100 g)。采用紫外分光光度法测定不同大豆品种籽粒总异黄酮的含量。结果表明:同一品种P2处理大豆总异黄酮含量显著高于P1、P3、P4处理,‘黑农37’、‘黑农44’、‘黑农48’3个品种大豆P2处理大豆总异黄酮含量分别比对照组增加3.7%、4.3%、3.8%;不同品种同一处理都是‘黑农44’总异黄酮含量最高;在12个处理组合中‘黑农44’P2处理总异黄酮含量最高,3个大豆品种异黄酮含量在品种间和施磷处理间差异显著。施磷对3个大豆品种异黄酮含量有影响,适宜的施磷量有利于提高大豆籽粒异黄酮的含量。 相似文献
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为了筛选出适宜在四川省低海拔地区适应性较强的红三叶品种。2007-2011年采用随机区组设计,对3个红三叶品种进行农艺学性状观测。结果表明:3个红三叶都能适应该地区的气候和土壤条件;从物候期来看,3个品种差异不大,“自由”返青期较其他2个品种早;从农艺性状来看,“自由”具有植株高大、匍匐分枝数最多等特点,其次是“岷山”;从干草产量来看,4年平均产量“自由”(9795 kg/hm2)显著高于“岷山”和“巫溪”(P<0.05),其次是“岷山”和“巫溪”,两者差异不显著;从田间表现来看,“自由”在3个参试品种综合表现最佳,是该地区的首推红三叶品种,其次是“岷山”和“巫溪”。 相似文献
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There is a need to evaluate grass varieties under grazing management to allow selection of varieties to increase animal performance. However, the evaluation of animal performance under grazing with each variety is arduous and time-consuming. An alternative is to describe the preference by grazing animals when given a choice of different varieties. Indeed, there is some indications that preference is related to variety characteristics such as leaf content or digestibility, characteristics having also an impact on the level of intake of this variety. However, preference for grass varieties, when sown alone, may not reflect agricultural practice as grasses often occur in mixed swards, associated with white clover. So, the aim of the present work was to determine whether, under grazing management, cattle expressed selections when given a choice of mixed swards in which different perennial ryegrass varieties were grown in association with a common white clover variety at two levels of fertilizer application (60 or 160 kg N ha−1 annum−1). The preference for perennial ryegrass variety per se was then assessed after taking white clover content into consideration. The results show that there were significant differences in preference for perennial ryegrass varieties, per se, even for varieties with the same heading date and ploidy. The effect of white clover cover on sward selection was more marked in swards which received the higher level of nitrogen fertilizer application which may have been related to a more variable white clover content between swards. This suggests that, under low nitrogen fertilizer application, differences in perennial ryegrass varieties preference can be determined in the same experiments as are used to determine ryegrass varieties persistence in association to white clover. Nevertheless, before such ‘variety preference’ tests can be applied in practice, a validation of the possible correlation between ‘variety preference’ and ‘variety intake’ will be necessary. 相似文献
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摘要:在试验的7种真菌中,最终浓度为30 mg/L的米根霉(Rhizopus oryzae)提取物作为真菌诱导子,在第18d加入可以使喜树(Camptotheca acuminata Decaisne)悬浮培养细胞喜树碱的总产量达到最大。在试验的4种抗褐变剂中,最终浓度为2 g/L的植酸作为抗褐变剂,在第15d加入可以使喜树悬浮培养细胞的生长和喜树碱的总产量达到最大。2 g/L的植酸在第15d加入后,再在18d加入30 mg/L的米根霉诱导子处理后,细胞干重在第24d达到最大值26.9 g/L,是未作任何处理细胞干重最大值的1.2倍(对照的在第20d达到最大值22.4 g/L)。综合处理的细胞喜树碱总产量在第26d达到最高值34.2 mg/L,是未作任何处理的喜树碱总产量的9.0倍(对照的在第20d达到最大值3.8 mg/L)。 相似文献
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果园种植三叶草对杂草群落及物种多样性的影响 总被引:3,自引:1,他引:3
为实现果园杂草生态控制,减少或避免使用化学除草剂。根据生态位先估和生态位竞争原理,设计间种豆科绿肥白三叶草和红三叶草两种杂草生态控制技术,同时设置清耕对照(CK),采用小样方多点取样连续两年调查果园杂草种群数量、生物量、平均株高等指标。结果表明:果园共有杂草13科28属34种;3个处理在4次调查时,对照杂草多度(Pi)高达1.001和1.000,间种白三叶草处理分别为0.755、0.664、1.001和0.945,间种红三叶草处理分别为0.986、0.889、0.982和0.992。种植白三叶处理果园在四次调查时期,杂草物种丰富度(S)和种群多样性(H)均大于对照,均匀度(J)在第一次调查时小于对照,优势集中性指数(C)均小于对照;间种红三叶草处理四次调查杂草总数量均低于对照。本研究表明间种白三叶草能改变果园杂草群落结构,有效控制杂草的生长。 相似文献
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将120只1日龄AA肉仔公鸡随机分为4组,在相同的饲养条件下,分别对试验组灌胃大豆异黄酮片30、100、200mg/kg(bw)3个剂量。在试验14、28、42d采血和剖杀,探讨不同剂量水平大豆异黄酮对肉仔公鸡免疫机能的影响。结果显示,大豆异黄酮可促进法氏囊和脾脏的发育,并且随剂量变化更为明显,脾脏指数和法氏囊指数随剂量的变化也较明显;T淋巴细胞的EtRFC%形成试验表明,与对照组相比,给予大豆异黄酮可以增加肉仔公鸡的T淋巴细胞数目,使细胞免疫功能加强 (P<0.05), 但是高剂量与低剂量组之间差异并不显著(p>0.05)。 相似文献
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J. Hill 《Plant Breeding》1993,110(3):212-219
Analysis of a half diallel cross among four white clover cultivars, grown as monocultures and in mixtures (duocultures) with two separate perennial rye-grass cultivars, confirmed that for stolon and leaf number a higher proportion of the genetic variance in duocultures was non-additive. For canopy height and dry weight, however, this proportion was less affected by inter-specific competition. An additive-dominance model of gene action sufficed for all four characters in monocultures, but in duocultures epis-tasis was just one of the factors complicating the genetic picture. This, coupled with short-term reversals in the direction of dominance, merely illustrates the complexity of breeding white clover cultivars. Possible future developments in the breeding of white clover are discussed in the light of these results. 相似文献
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氮磷钾对红花草固氮根瘤菌生长及种植后土壤肥力的影响 总被引:2,自引:0,他引:2
为了发展有机水稻,以红花草-有机水稻轮作培肥水田土壤肥力,研究氮、磷、钾对红花草固氮根瘤菌生长及种植后土壤肥力的影响,为红花草的合理种植、培肥地力提供依据。2012—2013 2年稻后茬种植红花草,过冬前分别单独施用不同用量的氮肥、磷肥、钾肥,以不施肥为对照,探讨不同肥料不同用量对红花草产草量、固氮根瘤菌数量、固氮根瘤菌重量的影响及种植后的土壤肥力变化状况。研究结果表明:红花草前期补施氮、磷、钾,氮素对红花草的影响较大,在施氮75 kg/hm2(N 46%)时,产草量最高,固氮根瘤菌数量最多,固氮根瘤菌重量大;种植后土壤全氮变化表现为不同施氮量增幅随肥料用量增加而增加,施磷、施钾各处理增幅随肥料用量增加而先降后升;土壤速效磷变化为施氮、施磷各处理增幅随肥料用量增加而增加,施钾各处理增幅趋势表现不明显;土壤速效钾变化表现为施氮、施磷各处理增幅变化趋势是随肥料用量增加先升后降,在施氮150 kg/hm2(N 46%)、施磷300 kg/hm2(P2O5 12%)时,土壤速效钾增幅达最大;土壤有机质变化表现为增幅随肥料用量增加而增加。所以,种植红花草,前期适当补施氮、磷、钾,可以提高红花草产草量,有效提高土壤肥力。 相似文献
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R. P. Mauro A. Occhipinti A. M. G. Longo G. Mauromicale 《Journal of Agronomy and Crop Science》2011,197(1):57-66
A field‐experiment (2004/2005 and 2005/2006 seasons) was conducted in the coastal plain of south‐eastern Sicily (37°03′N, 15°18′E, 15 m a.s.l.), on a Calcixerollic Xerochrepts soil, aimed at quantifying the effect of shading on chlorophyll (Chl) content, Chl fluorescence, photosynthesis and growth of subterranean clover. Four levels of photosynthetically active radiation reduction (from 0 % to 90 %) were tested on Trifolium brachycalycinum cv. ‘Clare’ and Trifolium subterraneum ecotype ‘Ragalna’. In both species shading progressively increased Fv/Fm, internal CO2 concentration, diffusive leaf resistance and specific leaf area (up to 8 %, 34 %, 18 % and 68 %, respectively), and decreased Chl content, Tmax, photosynthetic rate and plant dry weight (up to 9 %, 24 %, 79 % and 39 %, respectively). As plants aged, characteristic bell‐shaped trends were evident for photosynthetic parameters, with Fv/Fm increasing up until the onset of flowering, and thereafter declining. This implies that Fv/Fm may be a useful indicator of earliness in subterranean clover genotypes. The aboveground dry biomass response to shading was both genotype‐ and season‐dependent, but was predictable from the measurement of relative leaf Chl content. Moreover, our results suggest that an improvement in the interaction between host‐rhizobium may represent a major potential breeding target for enhancing subterranean clover tolerance to shading. 相似文献
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生物炭对红壤茶园溶磷细菌数量数量及和土壤磷形态转化有效磷含量的影响 总被引:1,自引:0,他引:1
为检测施用生物炭对酸性红壤土壤磷转化和土壤溶磷细菌数量的影响,用茶园土进了8周的接种溶磷细菌的微缩土壤培养实验,设置了0%、1%、3%(重量比)3种添加生物炭处理。结果表明:接种后土壤溶磷细菌数量迅速下降,而施用生物炭显著增加了茶园溶磷细菌的数量,为不施用生物炭的对照处理的10.5~15.25倍。此外,添加生物炭显著提高了土壤pH值、土壤有效磷(Bray-P)含量与土壤碱性磷酸酶活性。相关性分析结果表明:红壤茶园土壤溶磷细菌数量与土壤有机碳、总氮、总磷、有效磷、pH值、碱性磷酸酶活性之间均呈显著正相关关系,与土壤酸性磷酸酶活性呈负相关关系。总之,与对照处理相比较,添加生物炭可以增加红壤茶园土壤溶磷细菌的数量,并对土壤磷素起到活化作用。
关键词:生物炭;溶磷细菌;土壤有效磷;土壤碱性磷酸酶;红壤茶园 相似文献
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辣椒红色素的性质及其应用 总被引:2,自引:0,他引:2
辣椒红色素是以辣椒为原料,采用科学方法提取、分离、精制而成的天然色素,属类胡萝卜类色素,具有保健作用,广泛应用于食品、水产品、保健品、化妆品、医药和高级饲料等领域。就辣椒红色素的性质及其应用作一概述。 相似文献