Degradation of ricin in castor seed meal by temperature and chemical treatment

Oil from the seed of the castor plant (Ricinus communis L.) is an important commodity for a number of industries, ranging from pharmaceuticals to renewable energy resources. However, the seed and subsequent seed meal contain ricin (RCA₆₀), a potent cytotoxin, making it an unusable product. In order to investigate the efficiency of previously researched methods of reducing the toxicity of the meal, cold-pressed oil extracted seed meal known to contain ricin was boiled in the presence of 50 mM calcium hydroxide (pH 12.5). However, boiling of this seed meal in the presence of calcium hydroxide produced no significant difference from boiling alone. Therefore, heat and chemical treatments were performed to determine their effects on the denaturation of the ricin within whole seed, milled un-extracted seed, and cold-pressed extracted seed. Boiling and autoclaving showed varying degrees of effectiveness depending on the sample type. Ricin within the cold-pressed extracted meal was rendered unresponsive to antibody probing after 10 min of boiling or autoclaving. In contrast, treatment of cold-pressed extracted meal with 8 M urea and 6 M guanidine–HCl for 60 min produced no observable reduction in the response of the ricin to the antibody. Critically, hot pressing of the castor seed produced meal that exhibited no reactivity with the antibody, indicating that the ricin had been denatured during the oil extraction. By removing the toxic component of the castor meal, this by-product could create a new commodity from the production of castor oil, thereby making castor oil production more profitable.     

预防组培中蓖麻子叶节玻璃化的研究

为了预防蓖麻子叶节在组织培养过程中的玻璃化现象,以建立其高效的遗传转化体系,本实验对影响子叶节生长状态的几个因素进行了初步研究。结果表明,在胚轴、子叶均为淡黄色的时期切取蓖麻子叶节,接种在1/8MS、内含10g/L琼脂粉、20g/L蔗糖、8.0mg/LZT、1.0mg/LNAA的培养基中进行培养,能有效地预防蓖麻子叶节玻璃化。     

The feeding value of roasted castor oil bean (Ricinus communis) to growing chicks

A nutritive evaluation of roasted castor oil bean (Ricinus communis) was made using 150 day old crossbred progeny of barred Plymouth rock × Nigerian local chicken. The chicks were divided into five groups of 30 birds each. Each group was fed one of five iso-nitrogenous and iso-caloric diets A, B, C, D and E containing 0% (control), 10% non-roasted castor oil bean seeds (NRCOB), or 10, 15 or 20% roasted castor oil bean seeds (RCOB), respectively. Roasting was done at 140°C for 20 minutes in order to destroy the ricin component of the castor oil bean seed. There were significant (P<0.05) differences in average feed intake, daily gain, and feed conversion ratio between birds among the treatments. The best results were obtained with inclusion of RCOB at the 10% level. The birds fed the 20% roasted bean diets had the worst performance. The diet containing the 10% NRCOB supported little or no growth, and also resulted in a high mortality (83%) among the birds. There were no significant (P<0.05) differences in mortality rates between the control diet and the other diets containing RCOB.     

不同盐分胁迫对野生大豆种子发芽的影响

一年生野生大豆是栽培大豆的野生近缘种和基因资源,具有耐盐碱、抗寒、抗病等优良性状.研究其种子萌发的耐盐性,为利用盐碱地资源和野大豆的引种驯化供依据.以山东德州一年生野大豆为材料,研究NaCl、Na2SO4、Na2CO3及三者的混合盐的胁迫对野大豆种子的发芽率、发芽势、发芽指数及胚生长的影响.随盐溶液浓度的增加,野大豆种子的发芽率、发芽速度、发芽指数均呈下降趋势,而低浓度的Na2SO4(10～50 mmol·L-1),Na2CO3(0～10 mmol·L-1)促进种子萌发,高浓度的NaCl(＞200 mmol·L-1)、Na2SO4(≥200 mmol·L-1)、Na2CO3(≥75mmol·L-1)抑制种子萌发;10 mmol·L～Na2SO4处理下,其胚根胚轴长度都大于未经盐处理的,低浓度的盐分促进了胚根和胚轴的生长.结果表明低浓度的盐分促进一年生野生大豆胚的生长,野生大豆的胚根比胚轴对盐分更敏感.     

小麦种子萌发期抗早衰鉴定指标的初步研究

为了探索小麦抗早衰性的早期鉴定指标,采用种子萌发试验比较了不同抗早衰类型的33个小麦(Triticum aestivum L.)品种(系)萌发种子的芽长、胚芽鞘长、主胚根长、种子根数、根系活力、种子贮藏物质转运率、总鲜重、总干重、根芽干重、干物质含量等指标与抗早衰性之间的关系。结果表明,萌发种子的芽长、胚芽鞘长、主胚根长、种子根数、根系活力、总鲜重及根芽干重等7项指标均与小麦抗早衰性无明显相关性;萌发种子的总干重、干物质含量与小麦抗早衰性有部分相关性,但不能准确区分抗早衰型和典型早衰型品种(系);种子贮藏物质转运率能较好区分不同抗早衰类型的小麦品种,可作为小麦种子萌发期抗早衰性的鉴定指标。     

欧山羊草6Ub染色体附加对小麦萌发期抗旱性的改良作用

为探究欧山羊草U~b染色体附加对普通小麦抗旱性的遗传改良作用,选取2个普通小麦-欧山羊草异附加系(Ae9041和Ae9061,均附加了一对6U~b染色体)和3个普通小麦品种为材料,以聚乙二醇(PEG6000)模拟干旱胁迫,研究了不同小麦材料干旱胁迫后种子发芽势、发芽率、胚芽鞘长度、种子根数、胚根长度、幼苗高度以及贮藏物质利用率等抗旱相关指标的变化。结果表明,干旱胁迫抑制了各供试材料的种子萌发,且胁迫程度越大,抑制越明显。在相同浓度PEG6000处理下,两个异附加系的种子发芽势、发芽率和贮藏物质利用率的表现较为一致,且差异不显著。与耐旱品种晋麦47和节水品种石4185相比,Ae9041和Ae9061的幼苗胚芽鞘长、种子发芽率和贮藏物质利用率在干旱胁迫下均较高。在30%PEG6000胁迫下,Ae9041和Ae9061的种子发芽势、发芽率、幼苗胚芽鞘长、胚根长、幼苗高度均显著高于亲本中国春。由此可见,普通小麦-欧山羊草异附加系种子在干旱胁迫下能迅速吸水并整齐萌发,以发达的根系和较长的胚芽鞘促进幼苗地上部生长,并将胚乳营养快速转运至幼苗中,从而促进其较快地进行形态建成,也说明欧山羊草U~b染色体的附加能够改良小麦萌发期的抗旱性。     

Breaking primary dormancy in seeds of the perennial pasture legume tedera (Bituminaria bituminosa C.H. Stirt. vars albomarginata and crassiuscula)

Tedera (Bituminaria bituminosa vars. albomarginata and crassiuscula) is a perennial pasture species with agronomic characters ideally suited to Mediterranean climates. Tedera seed has a period of after-ripening or primary dormancy typically lasting three months, which delays assessment and breeding of elite hybrid varieties. Temperature, chemical and mechanical methods were investigated in conjunction with in vitro culture to circumvent this dormancy period across a range of parental and hybrid genotypes. Temperature treatment of T5 (Tedera accession 5) and T48 (Tedera accession 48) alone was not sufficient to break dormancy (24.0% and 14.7% germination); however, when combined with soaking in gibberellic acid (GA₃) and mechanical scarification resulted in 79.7% and 84.3% germination respectively. In an effort to further improve this result for valuable hybrid genotypes, we combined mechanical scarification with removal of seed coat after imbibition and in vitro culture on B5 medium until radicle emergence. This resulted in breaking dormancy from 96% to 100% of parent seeds and 100% of hybrid seeds. Hardening the germinated F₁ or F₂ seedlings 4 d after first transfer to in vitro culture resulted in 100% survival of plants to soil. This procedure is now used on a routine basis in the Australian tedera breeding programme.     

桃色顶孢霉发酵液对大豆的促生及其抗逆酶活性的影响

本实验采用了管碟法和种子萌发法研究了实验室分离获得的桃色顶孢霉对茄病镰刀菌F. solani.的拮抗作用以及对大豆的促生作用,并采用愈创木酚法、紫外吸收法、氮蓝四唑光化还原法研究了顶孢霉发酵液对POD、CAT、SOD三种抗逆酶活性的影响。结果表明：顶孢霉发酵液对镰刀菌菌丝生长有明显抑制作用,菌丝变稀疏。大豆种子经不同浓度桃色顶孢霉发酵液处理后,萌发率及种子酶活性均产生变化。不同浓度的发酵液对种子萌发促进作用不同,当发酵液浓度为10%时,胚根长,胚芽长,胚根鲜重,胚芽鲜重均达到最高值,分别为2.91cm,0.037g,4.07cm,0.1666g。与对照相比分别提高了49.37%,63.24%,30.54%,45.80%。当处理种子的发酵液浓度为60%时,种子萌发率最高为83.67%,与对照相比提高了23.90%;酶活性最强,POD、CAT和SOD分别为683U、160.67U和301U,与对照相比分别提高 73.50%,43.78%,76.73%。初步证实了桃色顶孢霉发酵液中含有能够促进大豆种子的萌发及抗逆酶活性升高的物质。     

不同有机酸对大豆生长的化感效应

试验采用发芽试验、水培试验及室内分析相结合的方法研究了经GC－MS检测出的大豆根系分泌物和根茬腐解液中的几种有机酸对大豆种子萌发及幼苗生长发育的化感效应。结果表明：3－硝基邻苯二甲酸、邻甲氧基苯甲酸、3，4－二氯苯甲酸、肉桂酸等四种有机酸均抑制了大豆种子的萌发，表现在萌发率、胚根长和 胚根干重与对照相比均有所降低，差异达显著或极显著水平，而且有机酸浓度不同，抑制程度也有所差别；3－硝基邻苯二甲酸、邻甲氧基苯甲酸、3，4－二氯苯甲酸、肉桂酸、邻苯二甲酸等五种有机酸不同程度地抑制了水培大豆幼苗的生长发育，表现在株高、干物质重、相对生长速率等均低于对照，差异达显著或极显著水平，且随着有机酸浓度的增加，抑制作用增强。     

Effects of Cadmium Stress on Seed Germination, Seedling Growth and Seed Amylase Activities in Rice (Oryza sativa)

Two rice varieties, Xiushui 110 with high cadmium (Cd) tolerance and Xiushui 11 with low Cd tolerance were used to study the effects of Cd stress on seed germination, seedling growth and amylase activities. The low cadmium concentration had little effect on seed germination rate. However, cadmium stress could significantly inhibit plumule and radicle growth, especially for radicle growth. Germination index, vigour index, radicle length and amylase activities of Xiushui 11 decreased more significantly with the increasing cadmium level compared with Xiushui 110. The cadmium content in seedlings of Xiushui 11 was higher than that in Xiushui 110 when the cadmium concentration exceeded 5 μmol/L, which caused lower mitotic index in root tips and amylase activities, and more serious cadmium toxicity in Xiushui 11.     

花生ω-3△~(15)-脂肪酸脱氧酶基因AhFAD3A的克隆及其表达

花生油中的α-亚麻酸含量在不同种质资源中存在着差异,与籽仁的不同发育时期也密切相关。本研究通过生物信息学分析并利用RACE的方法,从萌发的花生子叶中克隆了一个参与花生α-亚麻酸合成的ω-3△15-脂肪酸脱氢酶基因,命名为AhFAD3A。利用荧光定量PCR分别比较分析了AhFAD3A和Ah FAD8基因在花生不同组织、籽仁发育不同阶段、萌发过程中的表达特征,结果表明:AhFAD3A基因主要在花期的叶片组织和根部、籽仁形成期表达,在其它发育阶段该基因的表达量比较低,证实该基因的表达与花生籽仁中α-亚麻酸的形成呈正相关;AhFAD8基因在花生的整个生育阶段的绿色组织中表达、非光合组织中几乎不表达。以上研究结果为进一步确定AhFAD3A基因的功能、表达调控及其与花生籽仁中α-亚麻酸形成的关系提供了研究基础。     

萌发大豆种子中子叶细胞内质体发育与解体的变化

本文分别报道了大豆（ＧｌｙｃｉｎｅｍａｘＬ．）种子在光下和在暗处萌发过程中子对细胞内质体的发育及解体过程。电镜观察的结果表明，大豆种子在吸水膨胀期间，子叶细胞内只有较少的、近球形的（数量为１一３个、直径为３一４微米）原质体，其内有２—６个淀粉粒。随着吸水膨胀时间的加长，子叶细胞内质体数量、体积、淀粉粒都有所增加（数量为５—１０个、直径为５—６微来、淀粉粒为８－１２个）。播种后在光下发育４—８天期间，子叶细胞原质体内出现５—１０个散在于基质中的片层结构；播种１２天时，１０—２０个片层结构垛叠在一起构成基粒，其数量为２—８个。此时原质体发育成为叶绿体。１３－１９天后，子叶日起黄化枯萎，叶绿体内片层结构多处膨胀，被膜解体，基质中出现５—１０个脂质球。大豆种子在暗处发育时，子叶细胞的原质体内首先形成伸展的、数量为１５—２０个片层结构。随着发育，片尽结构增多，这些片层结构并合形成原片层体，以后逐渐收缩成紧密的晶格。随着子叶的衰败，原片层体解体。     

微胚乳超高油玉米种子萌发过程中子粒脂类化合物含量变化研究

对微胚乳超高油玉米种子萌发过程中子粒脂类化合物含量的生理生化及显微化学变化进行了研究。结果表明,微胚乳超高油玉米种子在萌发过程中,子粒质量在第1天没有变化,从第2天开始减小。子粒含油率在前3天变化不大,第4天开始减少,但每克种子绝对含油量在第3天开始下降,油分消耗速率最快的是第6天。种子酸价在种子萌发前4天均比干种子低,第5天开始上升,上升速率最快的是第7天。子粒油分的显微化学变化表明,种子油分消耗是在第3天开始的,到第7天时油分基本消耗殆尽。     

不同维生素浸种对玉米种子萌发的影响

以玉米杂交种郑单958为试验材料,采用不同质量浓度50、100、200 mg/L的水溶性维生素V_(B1)、V_(B2)、V_(B6)、V_(B12)、V_C、V_H、V_(PP)浸种24 h,处理后分析玉米种子萌发及胚芽和根生长中脯氨酸等可溶性调节物质情况。结果表明,供试维生素在100、200 mg/L处理下基本都呈现对种子萌发指数的促进,其中,100 mg/L维生素处理对种子萌发率促进效果显著;200 mg/L维生素处理对种子发芽势显著促进作用;50 mg/L维生素对上述3个指标的影响不同。与未处理对照相比,不同种类维生素和不同质量浓度的同一维生素对根冠比影响不同。维生素浸种均可引起玉米胚芽可溶性糖含量显著升高,外源维生素浸种处理可显著影响玉米种子萌发和胚芽及胚根的生长,且不同维生素在不同浓度下对各生长指标影响及脯氨酸等可溶性调节物质变化不尽相同,对种子萌发呈显著促进作用的V_(B2)和V_(B12)在玉米种子萌发中应用前景较好。     

【Short Report】Allelopathic Potential of White,Red and Black Rice CultivarsHisashi Kato-Noguchi1, Kenji Nitta2 and Tomio Itani2

Abstract

The inhibitory effect (allelopathic potential) of shoot, seed and root extracts of 8 white, 5 red and 5 black rice (Oryza sativa L.) cultivars was determined against the seedling growth of lettuce (Lactuca sativa L.) and white clover (Trifolium repens L.). All extracts inhibited hypocotyl and root growth of lettuce and white clover seedlings, and those inhibitory activities ranged from –1% – 96%. The average inhibitory activity of the extracts on the hypocotyl and root growth of lettuce and white clover was 42 – 88%. No apparent difference in the inhibitory activity was found either among the extracts of white, red and black rice, or among the extracts of shoots, seeds and roots. However, the red rice cultivar Tsushima-akamai marked the greatest inhibitory activity with an average of 88% growth inhibition on hypocotyls and roots of lettuce and white clover, followed by Souja-akamai and Koshihikari. These results suggest two red rice, Tsushima-akamai and Souja-akamai, may be potentially useful for weed management in agriculture.     

玉米丝黑穗病菌PCR检测

利用玉米丝黑穗病菌基因组特异引物PCR技术,检测了该菌对玉米植株的侵染状况,并对不同玉米品种在苗期对丝黑穗病菌的抗性进行了初步判断。研究结果表明,感病品种K12分别在接种后第3 d的茎中,6 d的茎,9 d的根、茎、叶,12 d茎,抗病品种20060分别在接种后第3 d的茎、6 d的茎、9 d的茎和叶、12 d的茎和15 d叶都能扩增出PCR特异片段,经过EM种衣剂包衣的玉米幼苗的根茎叶材料扩增出来的特异DNA条带明显少于未经包衣的玉米幼苗。EM包衣处理能够有效的提高玉米种子的抗病能力,减少了玉米丝黑穗病菌对幼苗的侵染机会,有效地防治了玉米丝黑穗病。     

Seed Treatment with Uniconazole Powder Improves Soybean Seedling Growth under Shading by Corn in Relay Strip Intercropping System

The relay strip intercropping system of wheat-corn-soybean is widely used in southwest China. However, it is hard to obtain a stable production of soybean with this system, since soybean plants grow under shading by corn; the stems are thinner and susceptible to lodging. We examined the effects of seed treatment with uniconazole powder (0, 2, 4 and 8 mg kg-¹ seed) on the growth of soybean seedlings under relay strip intercropping, some morphological characteristics and yield. The seedling height, first internode length, cotyledonary node height and leaf area per plant were decreased, while the stem diameter, root dry weight, shoot dry weight, root volume, leaf greenness and root to shoot dry weight ratio were increased by uniconazole treatment. The root vigor and root active absorption area were also increased significantly by uniconazole treatment. Moreover, 2 and 4 mg kg-¹ uniconazole powder treatment increased shoot dry weight, number of pods per plant, number of seeds per pod and seed yield significantly. Thus, the results suggested that seed treatment with uniconazole powder at a suitable concentration can improve soybean seedling growth, resist the lodging and also increase the seed yield under shading by corn in relay strip intercropping system.     

镉胁迫对不同水稻品种种子萌发、幼苗生长和淀粉酶活性的

以镉耐性不同的两个水稻品种秀水110(耐镉型)和秀水11(镉敏感型)的种子为材料,采用室内培养方法,研究了水稻种子萌发、幼苗生长和淀粉酶活性对Cd胁迫的响应。结果表明,在水稻种子萌发过程中,胚根和胚芽对Cd要比种子本身敏感,而胚根较胚芽更敏感。 Cd胁迫能显著影响发芽指数、活力指数、根长、淀粉酶活性,其中对秀水11的影响更明显;在高于5 μmol/L Cd浓度下,秀水11植株内的Cd含量明显高于秀水110,造成后者根尖有丝分裂指数和淀粉酶活性明显降低,受到的毒害更严重。     

Pre and postemergence herbicides for weed control in castor crop

Weed management is among the main factors limiting cultivation of castor (Ricinus communis) in extensive fields, particularly when labor is scarce or expensive. This experiment evaluated the efficiency of weed management programs using preemergence (clomazone, pendimethalin, and trifluralin) and a postemergence herbicide (chlorimuron-ethyl) applied at 20 days after emergence in castor plants cv. BRS Energia under rainfed conditions in Apodi, Brazil. No phytotoxicity was observed on the castor plants, and the postemergence herbicide significantly increased castor seed yield to 1466 kg ha⁻¹ complementing the weed control of preemergence herbicides treatments in which seed yield was 1207 kg ha⁻¹. Seed yield on weedy and weed-free treatments was 760 and 1971 kg ha⁻¹, respectively. Weeds were kept under a satisfactory control up to 40 days after emergence. This program resulted in reasonable weed control because the preemergence herbicides controled monocotyledon weeds, while the postemergence herbicide controlled broad leafed species being selective to castor plants.     

增强小麦种子萌发期抗旱性的植物生长调节物质的筛选与评价

为筛选能增强小麦萌发期抗旱性的植物生长调节物质,以绵麦228为材料,选用21种植物生长调节物质浸种24h,以清水浸种为对照,在20%PEG6000模拟干旱胁迫条件下,测定各处理的小麦种子发芽势、发芽率、发芽指数及苗高、胚芽鞘长度、根长、根数、根冠比、种子贮藏物质转运率等性状,并通过加权隶属函数法评价21种生长调节物质增强小麦萌发期抗旱性的综合效果。结果表明,在PEG6000胁迫下,供试的大部分植物生长调节物质均能在一定程度上增强小麦种子萌发期的抗旱能力,表现为种子发芽率、发芽势、发芽指数提高,苗高、胚芽鞘长度、根长和根数增加,根冠比、贮藏物质转运速率增大;不同植物生长调节物质对小麦萌发期抗旱能力的调控程度存在一定差异。通过加权隶属函数法分析,综合评价值(D值)排在前5位的植物生长调节物质分别为乙烯利、黄腐酸、氯化胆碱、赤霉素、吲哚丁酸·萘乙酸。除根长、根冠比外,其他鉴定指标与D值均呈显著或极显著正相关,其中苗高的相关系数最大(0.80),因此种子发芽势、发芽率、发芽指数、苗高、胚芽鞘长度、根数、种子贮藏物质转运率等指标可作为植物生长调节物质浸种调控小麦萌发期抗旱性的评价指标。