生长调节剂和青霉素对杜梨种子萌和下胚轴生长的影响（简报）

适当浓度的ＢＡ、ＧＡ、乙烯到和青霉素处理均可显著促进杜梨休眠种子的萌发,效果大小依次为ＢＡ、ＧＡ、青霉素、乙烯利。ＢＡ抑制下胚轴的加长生长而促进加粗生长。ＧＡ促进下胚轴的加长生长。适当浓度的乙烯利和青霉素对下胚轴加长生长加加粗生长均具促进作用。     

生长调节剂和青霉素对杜梨种子萌发和下胚轴生长的影响(简报)

适当浓度的BA、GA、乙烯利和青霉素处理均可显著促进杜梨休眠种子的萌发,效果大小依次为BA、GA、青霉素、乙烯利。BA抑制下肢轴的加长生长而促进加粗生长。GA促进下胚轴的加长生长。适当浓度的乙烯利和青霉素对下肢轴加长生长和加粗生长均具促进作用。     

拟南芥下胚轴原生质体的膜片钳全细胞记录（简报）

建立了拟南芥下胚轴原生质体的膜片钳全细胞记录方法,观测到的全细胞电流主要是外向K＋电流,其对胞外K＋浓度具有一定的依赖性,并为K＋通道阻断剂Ba2 显著抑制,外源ATP和Ca2 分别对拟南芥下胚轴原生质体的全细胞外向K 电流有显著影响,表明拟南芥下胚轴细胞质膜外向K＋通道,可能通过蛋白磷酸化或Ca2 信使调控的机制,参与细胞信号转导。     

影响油菜下胚轴外植体芽高频率再生的因素

以芥菜型油菜DB3 的下胚轴为外植体 ,分析了苗龄、激素、AgNO3 对油菜外植体的高频率再生的影响。结果发现 ,3～ 5d的苗用于诱导愈伤组织较佳 ,6 BA 1 .5mg/L +NAA 0 .1mg/L的组合对下胚轴芽的分化较好 ,AgNO3 可提高下胚轴芽的分化率     

植物生长调节剂对龙眼内源激素及花芽分化的影响

研究了ＰＰ３３３和ＧＡ对龙眼（ＤｉｍｏｃａｒｐｕｓｌｏｎｇａｎａＬｏｕｒ）,成花的作用及其与内源激素的关系。结果表明,ＰＰ３３３处理后,ｉＰＡ含量明显高于ＧＡ的处理,而ＧＡ含量则呈现由高到低逐渐下降的趋势,ＧＡ处理正好相反,ＰＰ３３３处理后芽中的ＡＢＡ含量明显低ＧＡ处理,表明高含量的ＧＡ和ＡＢＡ不利于花芽分化,而高含量的细胞分裂素则有利于花芽分化,外施Ｐ３３３可缩短花序长度,提高着果率和增加产量。     

钙对盐胁迫绿豆下胚轴生长的缓解效应（简报）

盐严重抑制绿豆下胚轴的延伸生长，5mmol·L-1的外源Ca2 对盐胁迫有一定的缓解效应。     

甘蓝型油菜下胚轴和带柄子叶再生体系研究

以甘蓝型油菜野油19号的下胚轴和带柄子叶为外植体,研究其下胚轴和带柄子叶在不同浓度激素配比下的分化率及再生频率的变化。该品系的油菜下胚轴和带柄子叶在1.5 mg/L的2,4-D中预培养4 d后,转入分化培养基中,其愈伤组织形成早,发生快,再生频率和分化频率均较高。其中,下胚轴转入MS+3 mg/L 6-BA+0.1 mg/L NAA培养基中的分化率和再生频率最高,再生频率达到86.67%;带柄子叶外植体的再生频率要比下胚轴的再生频率低,在MS+4 mg/L 6-BA+0.3 mg/L NAA的分化培养基中芽的再生频率为46.67%。本研究初步建立了甘蓝型油菜野油19号的高频率再生体系。     

关于植物细胞脱分化的研究概况

关于植物细胞脱分化的研究概况许萍张丕方（复旦大学生物系,上海２００４３３）ＧＥＮＥＲＡＬＡＣＣＯＵＮＴＯＦＳＴＵＤＩＥＳＯＮＤＥＤＩＦＦＥＲＥＮ－ＴＩＡＴＩＯＮＯＦＰＬＡＮＴＣＥＬＬＳＸｕＰｉｎｇＺｈａｎｇＰｉ－ｆａｎｇ（ＢｉｏｌｏｇｙＤｅｐａｒｔｍ...     

Studies on Plant Growth Regulators

The auxin activities of the homologs of racemic and enantiomeric α-alkylphenylacetic acids were estimated by pea straight growth test. The α-methyl, -ethyl and -propyl acids were moderately active whereas the longer and branched alkyl chain were found to make the molecule inactive. The more active enantiomers were shown to have the same configuration as the more active enantiomers in the other series of the optical active synthetic auxins.

The auxin activities of the cyclic homologs of 1, 2, 3, 4-tetrahydro- and 3, 4-dihydro-1- naphthoic acids were determined by pea straight growth test. In the tetrahydro-acid series, it was observed that the alicyclic ring expansion from the 6-membered to the 7-membered made the molecule inactive. In the 3, 4-dihydro-acid series, on the other hand, the activity remained almost unchanged by such a structural change. Structure-activity relationships were discussed in terms of their molecular structures, in particular, the configuration of the carboxyl group.     

Studies on Plant Growth Regulators

The electronic structure of atropic acid and its β-alkyl and β,β-dimethyl derivatives is calculated by a molecular orbital method. Their plant growth activity is shown to be explained only by considering an electronic factor of the molecule derived by the calculation.     

Effect of Plant Growth Regulators on Phytoremediation of Hexachlorocyclohexane-Contaminated Soil

The influence of three plant growth regulators, indolebutyric acid (IBA), thidiazuron (TDZ) and gibberellic acid (GA₃), either individually or in pair-wise combinations, on the ability of waxy corn plant to remove hexachlorocyclohexane (HCH) from contaminated soil was studied. Waxy corn seeds were immersed for 3 h in solutions of 1.0 mg/l IBA, 0.01 mg/l TDZ, 0.1 mg/l GA₃, or a mixture of two of the growth regulators, and then inoculated in soil contaminated with 46.8 mg/kg HCH for 30 days. Pretreatment of corn seeds with the plant growth regulators did not enhance corn growth when compared with those immersed in distilled water (control), but the pretreatment enhanced HCH removal significantly. On day 30, HCH concentration in the bulk soil planted with corn seeds pretreated with GA₃ or TDZ+GA₃ decreased by 97.4% and 98.4%, respectively. In comparison, HCH removal in soil planted with non-pretreated control waxy corn seeds was only 35.7%. The effect of several growth regulator application methods was tested with 0.01 mg/l TDZ. The results showed that none of the methods, which ranged from seed immersion, watering in soil, or spraying on shoots, affected HCH removal from soil. However, the method of applying the growth regulators may affect corn growth. Watering the corn plant with TDZ in soil led to higher root fresh weight (2.2 g) and higher root dried weight (0.57 g) than the other treatments (0.2–1.7 g root fresh weight and 0.02–0.43 g root dried weight) on day 30. Varying the concentrations of GA₃ did not affect the enhancement of corn growth and HCH removal on day 30. The results showed that plant growth regulators may have potential for use to enhance HCH phytoremediation.     

Effect of Plant Growth Regulators on Flower-Opening of Pharbitis nil

Flower buds of Pharbitis nil (due to open the next morning)cut from plants in the field before noon open very slowly bothin darkness and at a low temperature (20°C), unlike thebuds cut in the evening. On cool cloudy days, even the budscut in the evening open very slowly. Addition of sucrose, mineralnutrients or plant growth regulators other than ABA to the waterin which the cut buds were placed did not promote flower-openingunder such conditions, but addition of ABA (10–100 µM)greatly promoted it. IAA (100 µM) given alone or in combinationwith ABA suppressed floweropening completely. Mature flowerbuds placed in an ABA solution opened even under continuouslight at 25°C just as those kept in darkness without ABA;flower-opening occurred about 12 h after the application ofABA. ABA given to the buds in darkness at 25°C and thatgiven in continuous light at 20°C also advanced the timeof flower-opening. The action mechanism of ABA is discussed. ¹ This paper is dedicated to the memory of Dr. Joji Ashida,the first president of the Japanese Society of Plant Physiologist. (Received October 28, 1982; Accepted January 7, 1983)     

Studies on Herbicides and Plant Growth Regulators

With the aim of obtaining plant growth regulators, we have synthesized 1-aryloxyacylbenzimidazoles, 1-aryloxyacylindazoles, 2-aryloxyacyl-4,5,6,7-tetrahydroindazoles and 1-aryloxyacylbenzotriazoles by the acylation of azoles, and 1-aryloxyacyl-4,5,6,7-tetrahydroindazoles by the reaction of aryloxyacylhydrazines with 2-(hydroxymethylene)cyclohexanone. The structures of these compounds are discussed on the basis of nuclear magnetic resonance data.     

Effect of Plant Growth Regulators on Somatic Embryogenesis of Peucedanum terebinthaccum

The influence of different plant growth regulators including 2,4-D,ZT, 6-BA and ABA on somatic embryogenesis and the amount of endogenous ABA at different stages of embryogenesis was investigated. The effect of each plant growth regulator changed according to the stage of embryogenesis. The amount of endogenous ABA was rather high in single cell stage, decreased at cell clump and embryogenic cell clump stages and dramatically increased at globular embryo stage. It decreased again as the embryo developed. This change in amount of the endogenous ABA explained very well the difference in the effect of exogenous ABA when applied at different stages of embryogenesis.     

Phospholipids as Plant Growth Regulators

In this paper the potential to use phospholipids and lysophospholipids as plant growth regulators is discussed. Recent evidence shows that phospholipids and phospholipases play an important signalling role in the normal course of plant development and in the response of plants to abiotic and biotic stress. It is apparent that phospholipase A (PLA), C (PLC) and D (PLD), lysophospholipids, and phosphatidic acid (PA) are key components of plant lipid signalling pathways. By comparison, there is very little information available on the effect of exogenously applied phospholipids on plant growth and development. This paper serves to introduce phospholipids as a novel class of plant growth regulator for use in commercial plant production. The biochemistry and physiology of phospholipids is discussed in relation to studies in which phospholipids and lysophospholipids have been applied to plants and plant parts. Implicit in the observations is that phospholipids impact the hypersensitive response and systemic acquired resistance in plants to improve crop performance and product quality. Based on published data, a scheme outlining a possible mode of action of exogenously applied phospholipids is proposed.     

Effect of Plant Growth Regulators on Calcium-stimulated Serine Transport into Tobacco Cells

The transport of serine into tobacco cells (Nicotiana tabacum L.) cultured in liquid medium was examined. Transport was inhibited approximately 50% by 2,4-dichlorophenoxyacetic acid, indoleacetic acid, α-naphthalene acetic acid, and kinetin at a concentration of 10 micrograms per milliliter. Transport was not inhibited by 2,6-dichlorophenoxyacetic acid and inhibited less than 25% by p-chlorophenoxyacetic acid at this concentration. Removal of 2,4-dichlorophenoxyacetic acid from the transport medium resulted in an alleviation of inhibition. Gibberellic acid at concentrations from 2 to 20 micrograms per milliliter stimulated transport.

It was previously shown that inhibition of transport by La³⁺ was due to removal of Ca²⁺ from surface sites and inhibition of Ca²⁺ uptake by cells. None of the growth regulators tested had any significant effect on Ca²⁺ binding and/or transport.

A contributing factor to the low transport rates in the absence of Ca²⁺ is the increased rate of serine efflux. None of the growth regulators tested had any significant effect on the rate of serine efflux.

     

Nicotine Production by Tobacco Callus Tissues and Effect of Plant Growth Regulators

Relationships between callus origin and the nicotine contents as well as conditions of nicotine production in tobacco tissue cultures were investigated. Nicotine contents of callus tissues were remarkably affected by plant growth regulators in the culture medium. Thus, nicotine production was promoted by the regulators at lower concentrations, but gradually inhibited when the concentrations increased over an optimal region which was different among several kinds of the regulators. The nicotine contents also considerably depended on conditions of the callus induction as well as organ from which they were derived, at least just after callus induction. The differences due to the induction conditions were considered to be gradually lost during successive cultures. Thus, the nicotine contents appeared gradually to change to a certain level which mainly depended on the concentration of the regulators added to the culture medium. When such stabilized callus tissues were transferred to a culture medium containing another regulator or different concentration of the regulator, their nicotine contents rapidly changed to a new level depending on the culture conditions during a few successive cultures. The stabilized callus tissues grown on a medium containing 0.1 ppm α-NAA contained 0.5% of nicotine or more, which was almost the same level in root of the intact plant.     

Effect of Different Gibberellins on the Growth of the Hypocotyl

It has been stated earlier that hypocotyls of different plants show different growth response to added GA₃. It was suggested that this difference may be due to the requirement of some specific gibberellin. Hence hypocotyl growth response of three groups of plants has been studied with different gibberellins: group one showing no or insignificant growth response, group two showing 150–200 per cent growth response and group three showing 300–500 per cent growth response to added GA₃. Eight gibberellins were used, viz., GA₁, GA₂, GA₃, GA₄, GA₅, GA₇, GA₈ and GA₉, to test if this varying response is connected with the requirement of some specific gibberellin. In general, the results obtained do not favour this view. Iberis amara, a plant showing no response to added GA₃, Dianthus sp., a plant showing 150 to 200 per cent response and Lactuca satwa, Antirrhinum majus and Nicotiana tabacum, plants showing 300 to 500 per cent response, were promoted by all the gibberellins tested to a similar extent as by GA₃, with the exception of GA₈ which was inactive in most of the cases.