Inheritance of resistance to the bean-pod weevil (Apion godmani Wagner) in common beans from Mexico

The bean-pod weevil (BPW), Apion godmani Wagner, often causes heavy losses in crops of common bean (Phaseolus vulgaris L.). Farmers need resistant bean cultivars to minimize losses, cut production costs, stabilize seed yield, and reduce pesticide use and consequent health hazards. To design effective breeding methods, breeders need new and better sources of resistance and increased knowledge of their modes of inheritance. We therefore: (1) compared sources of resistance to BPW, (2) studied the inheritance of resistance, and (3) determined whether the sources possess similar or different genes for BPW resistance. The following sources of resistance, originating from the Mexican highlands, were evaluated for 3 years at INIFAP-Santa Lucía de Prias, Texcoco, Mexico: Amarillo 153, Amarillo 169, Hidalgo 58, J 117, Pinto Texcoco, Pinto 168, and Puebla 36. All except Puebla 36 were crossed with the susceptible cultivar Jamapa. Amarillo 153 and Puebla 36 were crossed with another susceptible cultivar, Bayo Mex. The parents, F₁ hybrids, and F₂ populations were evaluated for BPW damage in 1992. Backcrosses of the F₁ of Jamapa/Pinto 168 to the respective susceptible and resistant parents were also evaluated in 1992. All seven resistant accessions were crossed in all possible combinations, excluding reciprocals. The resulting 21 F₁ hybrids and 21 F₂ populations were evaluated for BPW damage in 1994. J 117 had the highest level of resistance to BPW. Pinto Texcoco and Puebla 36 had the highest mean damage score of all seven sources of resistance. The F₁ hybrids between susceptible parents and resistant sources were generally intermediate. Two genes segregating independently controlled the BPW resistance in each accession. One gene, Agm, has no effect when present alone, whereas the other gene, Agr, alone conferred intermediate resistance. When both genes were present, resistance to BPW was higher. Based on mean BPW damage scores, all 21 F₁ hybrids and their F₂ populations, derived from crosses among seven resistant accessions, were resistant. However, data from individual plant damage scores in F₂ populations of Amarillo 169/Pinto 168 and Pinto Texcoco/Pinto 168 suggested that at least one gene in each of the three accessions was non-allelic. Data also indicated that Amarillo 169 had a dominant gene that conferred high levels of BPW resistance, irrespective of the alleles at the other locus; and that Pinto Texcoco and Pinto 168 possessed two different genes for intermediate resistance.     

The structure of the incompatibility factors of Schizophyllum commune: Constitution of the three classes of B factors

Summary The B factors of Schizophyllum commune are of 3 classes: The high recombining class I has 7 alleles and 7 alleles; the low recombining classes are class II with 7 allels and probably 2 alleles and class III with probably 2 (or also 2) alleles and 7 allels. A fourth hypothetical class (-) was not found and either does not exist or is indistinguishable from class III by the tests employed. The and alleles differ from and by either (a) mutations affecting both mating specificity and recombination frequency, or (b) deletions involving most of the B region.The research was supported by a grant from the Atomic Energy Commission of the U.S. No. (30-1)-3875 and was performed at the Biological Laboratories, Harvard University, Cambridge, Mass., U.S.A.     

Sterol conjugates of two phenotypically different calli of Beta vulgaris

Steryl glycosides are the predominant form of sterol at 88% of the total sterol in non-betalain producing calli of Beta vulgaris. The total sterol decreases and sterol form shifts from steryl glycosides to 97% free sterol upon the transition of non-betalain to betalain producing calli. A substantial decrease in stigmasterol (24--ethylcholesta-5,22E-dien-3-ol) and sitosterol (24-ethylcholest-5-en-3-ol) levels is observed during this transition, and alters the ratio of ⁷:⁵ sterols. Spinasterol (24- ethyl-5-cholesta-7,22E-dien-3-ol) is the dominant sterol at 43% and 95% of the total sterol in non-betalain producing and betalain producing calli. The level of 22-dihydrospinasterol (24-ethyl-5-cholest-7-en-3-ol) is reduced in both calli to 3% from 25% in leaves. Lanosterol (4,4,14-trimethyl-cholesta-8(9),24-dien-3-ol) and cycloartenol (9,19-cyclopropyl-4,4,14-trimethyl-cholest-24-en-3-ol) were identified in betalain and nonbetalain producing callus respectively.     

Synthetic substrates in the histochemical demonstration of intestinal disaccharidases

Summary The splitting of 6-Br-2-naphthyl-, -naphthyl-, and 4-Cl-5-Br-3-indolyl-glycosides which proved useful for the assessment of cytological localization of intestinal enzymes in previous studies was investigated using isolated human and rat intestinal disaccharidases as a source of enzyme activities.Previous findings based on histochemical studies were confirmed and extended. 6-Br-2naphthyl-D-glucoside is cleaved by glucoamylase and sucrase-isomaltase. The participatio of trehalase in splitting of this substrate is very low and can be neglected. The mentioned -glucosidases are responsible for the brush border staining of enterocytes with this substrate when unfixed cold microtome sections are used. Even when a differential heat inactivation of sucrase-isomaltase and of glucoamylase occurs during paraffin embedding (so that the staining in paraffin sections is due mostly to glucoamylase) the use of natural substrates is desirable for a more precise assessment of sucrase-isomaltase activity (but without the possibility of a correct localization).4-Cl-5-Br-3-indolyl--D-fucoside is the substrate of choice for the demonstration of lactase. Even when this substrate is split also by hetero--galactosidase and by acid (lysosomal) -galactosidase these activities do not disturb the histochemical demonstration of lactase. If however some doubts arise, the inhibition with p-Cl-mercuribenzoate (2 · 10^–4 M) is to be emloyed (lactase activity is not inhibited). Due to a low K_m and a high V_max of indolyl-fucoside and due to its extreme stability in solution (which enables to use the substrate solution repeatidly) this substrate is suitable in routine practice even though it is expensive. -naphthyl- and 4-Cl-5-Br-3-indolyl--D-glucosides are split by lactase and -glucosidase. Due to the fact that the mutual delineation of these activities is not easy and that K_m an V_max for lactase are not so favourable as in the case of fucoside these substrates are not recommended for the assessment of lactase.6-Br-2-naphthyl--D-glucoside is the substrate of choice for the histochemical studies concerned with hetero--galactosidase and 4-Cl-5-Br-3-indolyl--D-galactoside for acid -galactosidase.     

Crystal formation in cultures of fungi II

Summary The present study offers the picture of crystal formation in cultures of dermatophytes photographed in white light. Isometric and anisometric crystal forms are profusely depicted. Pranks and mimics of crystal forms are pointed out. Photomicrographic data are given.

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Zusammenfassung In der vorliegenden Untersuchung wird das Bild der Krystallbildung in Dermatophytenkulturen in weissem Licht dargestellt. Isometrische und anisometrische Krystallformen werden reichlich illustriert. Auf Streiche und Nachahmungen der Krystallformen wird hingewiesen. Photomikrographische Daten sind gegeben.

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Résumé La présente étude offre le tableau des formations des crystaux des dermatophytes photographiées en lumière blanche. Des formes isométriques et anisométriques des crystaux ont été illustrées abondamment. Des coups et des mimiques des crystaux sont présentés. Les données photomicrographiques ont été élucidées.

     

Transmission of primary trisomics in pearl millet

Summary Transmission rates of extra chromosomes found in the full set of trisomics of pearl millet (Pennisetum americanum) (2n = 14) were estimated by examining the progeny of selfed trisomics and the progeny of trisomics crossed to disomics. When the trisomics were selfed, dark green and tiny had the highest transmission rate (23.8% and 23.3%, respectively) and pseudonormal the lowest (13.8%). Other trisomics had an intermediate rate of transmission. When the trisomics were used as females in crosses with disomics, both dark green and tiny again had the highest transmission rate and pseudonormal the lowest. When the trisomics were used as males in crosses to disomics, no trisomic was transmitted to the progeny except for spindle, and this occurred with a very low frequency (2.0%). A variation in transmission rate was observed from plant to plant and season to season for the same trisomic type. A study of the transmission rate of the extra chromosomes indicated that the following factors were probably contributing to the lower rate of transmission: small- or light-weight seeds tended to have a higher proportion of trisomics than heavier seeds; lighter seeds had a lower percentage germination; a positive and significant correlation was noticed between trivalent frequency and transmission rate. Plants with reduced vigour produced a higher frequency of trisomics. Though trisomics involving longer extra chromosomes showed a high degree of pollen and ovule sterility, they were highly transmissible. This has resulted in a close relationship between gametic sterility and transmission rate of extra chromosome.     

Biosynthesis of (1,3)(1,4)-β-glucan and (1,3)-β-glucan in barley (Hordeum vulgare L.)

Mixed membrane preparations from the coleoptiles and first leaves of young barley (Hordeum vulgare L. cv. Triumph) plants catalysed the synthesis of 55% methanol-insoluble labelled material from UDP[U-¹⁴C]glucose, the main components of which were identified as (1,3)(1,4)-- and (1,3)--D-glucans. The membrane preparations also catalysed the transformation of UDP-glucose into labelled low-molecular-weight products, mainly glucose (by phosphatase action), glucose-1-phosphate (by phosphodiesterase action) and glyco(phospho)lipids (by glycosyltransferase action). The formation of (1,3)(1,4)--glucans, (1,3)--glucans, and the other reactions competing for UDP-glucose, were monitored simultaneously and quantitatively by a novel procedure based on enzymatic analysis, thin-layer chromatography and digital autoradiography. Thus it was possible (i) to optimise conditions to obtain (1,3)(1,4)--glucan synthesis or (1,3)--glucan synthesis in isolation, and (ii) to study the influence of temperature, pH, cofactors, substrate concentration etc. on the (1,3)(1,4) and (1,3)--glucan synthesis reactions even when both occurred together. The synthesis of both -glucans was optimal at 20°C. In Tris-HCl buffer, the pH optima for (1,3)(1,4)--glucan synthesis and (1,3)--glucan synthesis were pH 8.5 and pH 7.0, respectively. Both glucan-synthesis reactions required Mg²⁺: (1,3)--glucan synthesis was optimal at 2 mM, whereas (1,3)(1,4)--glucan synthesis continued to increase up to 200 mM Mg²⁺, when the ion was supplied as the sulphate. (1,3)--Glucan synthesis was Ca²⁺ dependent and this dependence could be abolished by proteinase treatment. The K _m with respect to UDP-glucose was 1.5 mM for (1,3)--glucan synthesis and approximately 1 mM for (1,3)(1,4)--glucan synthesis. The (1,3)(1,4)--glucan formed in vitro had the same ratio of trisaccharide to tetrasaccharide structural blocks irrespective of the experimental conditions used during the synthesis: its enzymatic fragmentation pattern was indistinguishable from that of barley endosperm (1,3)(1,4)--glucan. This indicates either a single synthase enzyme, which is responsible for the formation of both linkage types, or two enzymes which are very tightly coupled functionally.Abbreviations G4G4G3G Glc(1,4)Glc(1,4)Glc(1,3)Glc (-linked) - UDP-Glc uridine-5-diphosphate glucose We are grateful to the Commission of the European Communities for the award of Training Fellowships to Christine Vincent and Martin Becker.     

P2Y6 nucleotide receptor activates PKC to protect 1321N1 astrocytoma cells against tumor necrosis factor-induced apoptosis

1. We recently reported that the activation by UDP of rat P2Y₆ nucleotide receptors expressed in 1321N1 astrocytoma cells protected them from TNF-induced apoptosis by suppressing activation of caspase 3 and 8. This study aims to characterize the involvement of intracellular signaling pathways, including kinases, involved in the antiapoptotic effect of UDP.2. Cell death was induced in 1321N1 astrocytoma cells permanently expressing the rat P2Y₆ receptor by exposure to TNF in the presence of cycloheximide. The apoptotic fraction was analyzed using flow cytometry.3. The activation of P2Y₆ receptors by UDP both protected the astrocytes from TNF- induced apoptosis and activated protein kinase C (PKC) isotypes. The phorbol ester PMA also activated PKC and protected the cells from TNF-induced cell death. The - and -isotypes of PKC were both activated in a persistent fashion upon 5-min exposure to either UDP (10 M) or the phorbol ester PMA (100 nM). The PKC isotype was markedly activated upon UDP treatment.4. The addition of PKC inhibitors, GF109203X or Gö6976, partially antagonized the protective effect of UDP and reduced the UDP-induced phosphorylation of extracellular signal-regulated protein kinases (Erk). The inhibitors of Erk, PD98,059 or U0126, antagonized UDP-induced protection.5. The antiapoptotic protein, Akt, was not affected by P2Y₆ receptor activation. Incubation of the astrocytes with calcium modifiers, BAPTA-AM or dantrolene, did not affect the UDP-induced protection from apoptosis.6. The addition of phospholipase C (PLC) inhibitors, D609 or U73122, partially antagonized both UDP-induced protection and PKC activation.7. Therefore, it is suggested that P2Y₆ receptors in 1321N1 cells, through coupling to PC-PLC and PI-PLC, activate PKC to protect against TNF -induced apoptosis, in which the activation of Erk is involved in part.     

Intracellular sites of the synthesis of sweet potato mitochondrial F1ATPase subunits

Summary Five subunits (-, -, -, - and -subunits) of the six -and -subunits) in the F₁ portion (F₁ATPase) of sweet potato (Ipomoea batatas) mitochondrial adenosine triphosphatase were isolated by an electrophoretic method. The - and -subunits were not distinguishable immunologically but showed completely different tryptic peptide maps, indicating that they were different molecular species. In vitro protein synthesis with isolated sweet potato root mitochondria produced only the -subunit when analyzed with anti-sweet potato F₁ATPase antibody reacting with all the subunits except the -subunit. Sweet potato root poly(A)⁺RNA directed the synthesis of six polypeptides which were immunoprecipitated by the antibody: two of them immunologically related to the -subunit and the others to the - and -subunits. We conclude that the -subunit of the F₁ATPase is synthesized only in the mitochondria and the -, - and -subunits are in the cytoplasm.     

Carotenoid pigments of Sorangium compositum (Myxobacterales) including two new carotenoid glucoside esters and two new carotenoid rhamnosides

Summary The carotenoid pigments of the myxobacterium Sorangium compositum were analyzed by chromatographical and chemical techniques and by visible, infra red, and mass spectroscopy. Besides -carotene, neurosporene, torulene, lycopene, and 1,2-dihydro-1-hydroxy--carotene, four new carotenoid glycosides were found. These pigments were identified as 1,2-dihydro-1-hydroxy-torulene glucoside ester (I), 1,2-dihydro-3,1-dihydroxy-torulene glucoside ester (III), 1,2-dihydro-1-hydroxy-torulene rhamnoside (II), and 1,2-dihydro-3,1-dihydroxytorulene rhamnoside (IV).Fifth communication on the carotenoids of myxobacteria. Fourth communication see Arch. Mikrobiol. 76, 364–380 (1971).     

Partial mispairing and crossing-over between β0 and δ genes as the origin of the δ β0 thalassemia gene

Summary Two double heterozygous ⁰/⁰ thalassemic sibs of Mexican descent were studied. The father had a ⁰/⁰ genotype, while the mother, one sib and several maternal relatives were ⁰/⁰ heterozygotes. Parental consanguinity and an apparently low frequency of thalassemia among Mexicans suggested a possible common origin of both ⁰ and ⁰ genes. A hypothesis to explain such a possibility is proposed on the basis of a partial mispairing between ⁰ and genes followed by a crossing-over which would results in a ⁰ recombinant gene. This hypothesis could also be extended to explain the 22 gluala, 22 alaglu and 116 arghis Hb variants as recombinants from double crossing-over between and mispaired genes for which the name interstitial-Lepore is proposed.     

Growth vigour of some Egyptian cotton variety seedlings in relation to selected rhizospheric microflora antagonistic toRhizoctonia solani Kuhn

Summary Growth responses of Ashmouni and Karnak cotton variety seedlings toRhizoctonia solani, the damping-off fungus, or toBacillus subtilis (two different strains),Aspergillus terreus andAspergillus flavus isolated from the rhizosphere of cotton, and all antagonistic to the pathogen, were expressed in terms of growth-vigour criteria.The presence ofR. solani in the soil inhibited the growth vigour of both cotton variety seedlings. However, Karnak seedlings were more sensitive to the pathogen than Ashmouni seedlings. One of the strains ofB. subtilis andA. terreus generally increased the vigour of both cotton variety seedlings.A. flavus lowered most of the growth criteria of Karnak or Ashmouni cotton seedlings.

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Zusammenfassung Rhizoctonia solani, der Parasiet von Baumwolle-Keimlingen, wurde isoliert.Sowohl Bacillus subtilis als auchAspergillus terreus und Aspergillus flavus wurden von der Rhizosphere der Baumwolle-Pflanzen isoliert. Diese Organismen wurden als antagonistisch gegenRhizoctonia solani erkannt. Die Wirkung dieser Organismen auf das Wachstum von Keimlingen der Baumwolle sorten Ashmouni und Karnak wurde untersucht. R. solani hemmt das Wachstum der Keimlinge beider Baumwolle-Sorten. Es wurde festgestellt, dass Karnak empfindlicher ist als Ashmouni. Einer der Stämme vonB. subtilis undA. terreus erwiesen sich als Wachstum förderend bei beiden Baumwolle-Sorten.A. flavus dagegen vermindert das Wachstum von Karnak und Ashmouni.

     

ααααanti-3.7 type II: a new α-globin gene rearrangement suggesting that the α-globin gene duplication could be caused by intrachromosomal recombination

Summary We report here a new human -globin gene rearrangement carrying the two normal, 2 and 1, and two hybrid, 1/2, globin genes in the order 5-2-1/2-1/2-1-3. Both the hybrid genes, subtyped with ApaI and RsaI restriction enzymes, were found to be of the uncommon anti 3.7 type II. The hybrid genes were expressed at the biosynthetic level and their interaction with the -thalassaemia IVS 1 nt 1 GA mutation caused thalassaemia intermedia. We also report a case of an -globin gene rearrangement in the twin of one of the -globin gene carriers; the duplicated gene was of the anti 4.2 type and was associated with the absence of RsaI polymorphism. The singular finding of an -anti 3.7 cluster with two identical rare hybrid genes suggests that the reciprocal unequal recombination causing the -globin gene rearrangements could be of the intra-chromosomal rather than the interchromosomal type.     

Long-term continuous reaction of immobilized β-fructofuranosidase

Summary -Fructofuranosidase was immobilized by alginate gel at high efficiency (92 %). The extreme long-term continuous reaction (half-life, 275 days) was achieved by the immobilized enzyme using sucrose at high concentration (500 mg ml^–1) to produce fructo-olicosaccharides, such as 1-kestose (Fru21Fru21aGlc) and nystose (Fru21Fru21Fru21aGlc).     

A human SP-C promoter fragment targets α1-proteinase inhibitor gene expression to lung alveolar type II cells in transgenic mice

A 1.277 kb promoter fragment of the gene encoding one of the lung surfactant proteins, SP-C, was cloned from a human genomic library and characterized using the human 1-proteinase inhibitor (1PI) gene as reporter. Messenger RNA for human 1PI isolated from a single transgenic mouse line was detected solely in lung tissue. Using immunogold electron microscopy, accumulation of human 1PI was shown unambiguously to occur only in type II pulmonary cells and, in discrete amounts, in the alveolar lining fluid. The protein was secreted and glycosylated showing a molecular weight close to that of plasma-derived human 1PI.     

Different ζ globin gene deletions among Black Americans

Summary Four types of chromosomes with a deletion between the human embryonic and globin genes were identified among 2.8% of 321 Black Americans from Georgia. Two deletions of approximately 11 kb which differed by about 300 bp occurred on chromosomes with or without a polymorphic Xba I site 5 to the globin gene [(X⁺) or (X^-)]. The deletions are identifiable in Xba I digests of genomic DNA using an or a globin gene probe which yield fragments of 23 kb from (X⁺)–^* chromosomes or 27 kb from (X^–)–^* chromosomes. Digestion with other enzymes and probing with both and probes gave fragments typical of the two globin gene deletions previously identified in Polynesians. Among Black Americans, these globin gene deletions have been found in combination with globin gene deletions in trans but not in cis. Homozygotes have not been found. Hematologic data on carriers of the globin gene deletions in association with Hb AS, SS, and SC suggest that these deletions have no effect on the function of the adult globin genes.     

A simple method for maintaining high multiplication of Narcissus shoot cultures in vitro

A simple method for stimulating and maintaining high in vitro multiplication of Narcissus shoot clump cultures was developed. Shoot clumps were subjected either to normal cutting where leaves were trimmed to 20 mm in length at the beginning of each culture passage or to severe cutting where shoot clumps were cut down to the basal plate region removing all green tissue. Severe cutting at the beginning of each culture passage initially doubled the leaf multiplication, compared to normal cutting, but the difference between cutting treatments declined in successive passages. The improvement in leaf multiplication was maintained when shoot clumps were subjected to severe cutting only at every other culture passage, with no cutting in the alternate recovery passages. In vitro multiplication was increased by severe cutting in all seven Narcissus cultivars which were tested.Abbreviations NAA-1 naphthylacetic acid - BAP benzylaminopurine     

Predominance and tissue specificity of adenine methylation in rice

Summary Using A and C methylation-specific restriction enzymes, namely, MboI, Sau3AI, DpnI, MspI, and HpaII, total rice cv Basmati 370 DNA, repetitive DNAs, and a specific repeat sequence indicated an abundance of adenine methylation. Although cytosine methylation in 5-CCGG-3 sequences suggested more CpC methylation than CpG, the C methylation in sequence 5-GATC-3 was comparatively less than A methylation. Furthermore, the presence of adenine methylation was tissue specific; it was predominant in rice shoot DNA as compared to embryo DNA. This pattern was also observed in two other cultivars of rice, i.e., R-24 and Sona, and was again confirmed using a cloned probe of a specific repeat sequence. Besides the changes in adenine methylation, there was also a qualitative change in 5mC from CpG to CpC dinucleotides in these two tissue systems.     

A simple brassinolide analogue 2α, 3α-dihydroxy-17β-(3-methyl-butyryloxy)-7-oxa-B-homo-5α-androstan-6-one which induces bean second internode splitting

A new synthetic brassinolide analogue, 2,3-dihydroxy-17-(3-methylbutyryloxy)-7-oxa-B-homo-5-androstan-6-one (11), has been shown to exhibit typical brassinolide activity characterised by elongation, swelling, twisting and splitting of the bean second internode. It was prepared from the known lactone 2,3,17-trihydroxy-7-oxa-B-homo-5-androstan-6-one (4) which was transformed to an isopropylidenedioxy derivative. After protection of the 2- and 3-hydroxy groups it yielded the 2,3-isopropylidenedioxy-17-(3-methyl-butyryloxy)-7-oxa-B-homo-5-androstan-6-one (7) on treating with 3-methylbutyryl chloride in pyridine. The analogue with a 2-methylbutyric moiety (10, 2,3-dihydroxy-17-(2-methyl-butyryloxy)-7-oxa-B-homo-5-androstan-6-one) in position 17 stimulated only elongation and swelling of the bean second internode. However, in this bioassay 100 times more 10 or 11 compared to 24-epibrassinolide is required to obtain the same effects. Analogues with -oriented hydroxyl groups at C-2 and C-3 (14,15), a 6-ketone (17,18) or 6-oxa-7-oxo-lactone system (12,13) in ring B lack the typical brassinolide activity. In addition, the active brassinosteroids applied to the second internode stimulated a similar, but 30% lower elongation of the first internode. From data presented here we conclude that the presence of two hydroxy groups in the positions 22 and 23 of the brassinolide side chain, which are considered as a key structural requirement, is not absolutely necessary for a compound to exhibit typical brassinosteroid activity. Nevertheless, these compounds have generally 2–10 times lower activity than that having 22,23-vicinal diol in the side chain.     

A novel type of somatic embryogenesis in Coffea arabica

A novel type of somatic embryogenesis characterized by an efficient and highly synchronized embryo formation was observed in embryogenic callus of Coffea arabica initiated on Murashige and Skoog medium containing kinetin (4 mg/l) and 2,4-D (1 mg/l). It occurs in suspension and goes along with the suppression of High Frequency Somatic Embryo Induction (HFSE). This is achieved by favoring during cultivation senescence-or necrosis-like processes which apparently do not impair the competence for embryogenesis. Since the resulting embryos germinate at a rate of 94.5 % without the need of a maturation step, we propose the term Self-Controlled Somatic Embryogenesis (SCSE).In addition, HFSE was optimized using half-strength liquid medium with 0.1 mg/l kinetin and 0.25 mg/l 2,4-D for proliferation of embryonic tissue, and 2.6 mg/l ABA for maturation of embryos. Yields as well as germination rates of HFSE embryos were markedly lower as compared to SCSE.Abbreviations ABA abscisic acid - BAP 6-benzylaminopurine - 2,4-D 2,4-dichlorophenoxy-acetic acid - NAA 1-naphthaleneacetic acid - HFSE high frequency somatic embryo induction - LFSE low frequency somatic embryo induction - SCSE self-controlled somatic embryogenesis