Isolation and characterization of a novel transcriptional repressor GmERF6 from soybean

Y. Zhai, J. -W. Li, X. -W. Li, T. -T. Lei, F. Yan, Y. Zhao, Y. -J. Li, L. -T. Su, Y. Wang, Q. -Y. Wang

Biologia plantarum 57:26-32, 2013 | DOI: 10.1007/s10535-012-0146-7

A new ethylene response factor (ERF), GmERF6, was isolated from soybean. Protein sequence alignment of GmERF6 revealed an AP2/ERF domain, two putative nuclear localization signals (NLSs) and an ERF-associated amphiphilic repression (EAR) motif. Real-time quantitative PCR analysis revealed that the expression of GmERF6 was differentially induced in soybean seedlings by drought, salt, cold, salicylic acid, ethylene, abscisic acid and methyl jasmonate. Transient expression experiments demonstrated that GmERF6 functions as a transcriptional repressor to downregulate the transcriptional levels of the reporter gene and repress the activated...

Photosynthetic parameters of Ulmus minor plantlets affected by irradiance during acclimatization

M. C. Dias, G. Pinto, C. M. Correia, J. Moutinho-Pereira, S. Silva, C. Santos

Biologia plantarum 57:33-40, 2013 | DOI: 10.1007/s10535-012-0234-8

In order to set up large-scale acclimatization protocols of micropropagated plants, an in-depth knowledge of their physiological responses during in vitro to ex vitro transfer is required. This work describes the photosynthetic performance of Ulmus minor micropropagated plants during acclimatization at high irradiance (HI; 200 ± 20 μmol m^-2 s^-1 or low irradiance (LI; 100 ± 20 μmol m^-2 s^-1). During this experiment, leaf pigment content, chlorophyll a fluorescence, gas exchange, stomata morphology, the activity of the Calvin cycle enzymes and saccharides were...

The plant activator BTH promotes Ornithogalum dubium and O. thyrsoides differentiation and regeneration in vitro

O. M. Tun, A. Lipsky, T. Luzzatto Knaan, Z. Kerem, I. Yedidia

Biologia plantarum 57:41-48, 2013 | DOI: 10.1007/s10535-012-0254-4

Benzothiadiazole (BTH) is a structural analogue of salicylic acid (SA) which is widely recognized for its role in elicitation of systemic acquired resistance in a broad range of plant species. Here, BTH was applied to cell cultures of the bulbous ornamental plants Ornithogalum dubium and O. thyrsoides, showing a strong effect on rates of differentiation and morphogenesis. Morphogenic cell clusters in liquid Murashige and Skoog (MS) medium containing 1-naphthaleneacetic acid (NAA) and 6-benzylaminopurine (BAP) were used for all treatments. The calluses were washed thoroughly and activated with increasing concentrations of BTH. Following...

Anthocyanin accumulation and expression analysis of biosynthesis-related genes during chili pepper fruit development

C. Aza-González, L. Herrera-Isidrón, H. G. Núñez-Palenius, O. Martínez De La Vega, N. Ochoa-Alejo

Biologia plantarum 57:49-55, 2013 | DOI: 10.1007/s10535-012-0265-1

Chili pepper (Capsicum annuum L.) cv. Árbol and Uvilla fruits differing in anthocyanin contents were analyzed to characterize the accumulation patterns. The maximum accumulation of the aglycon delphinidin occurred 20 days postanthesis (DPA) with higher content in Uvilla than in Árbol fruits. Regarding the cDNA library, 9 186 cDNA clones were selected. The clones with high homology to genes concerning anthocyanin biosynthesis, such as encoding chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), flavonoid 3',5'-hydroxylase (F3'5'H), dihydroflavonol 4-reductase (DFR), anthocyanidin synthase (ANS), UDP Glc-flavonoid...

Molecular cloning and expression analysis of a new stress-related AREB gene from Arachis hypogaea

L. Hong, B. Hu, X. Liu, C. Y. He, Y. Yao, X. L. Li, L. Li

Biologia plantarum 57:56-62, 2013 | DOI: 10.1007/s10535-012-0236-6

An AREB gene, designated as AhAREB1, was cloned from peanut (Arachis hypogaea L.). The gene contains a 1 338-bp open reading frame that encodes a putative protein of 445 amino acids. The corresponding genomic DNA containing four exons and three introns was isolated and analyzed. An upstream 1 060-bp DNA promoter fragment of the AhAREB1 gene was also amplified from peanut genomic DNA. Multiple sequence alignment of the deduced amino acids of AREB showed that the AhAREB1 protein shares high sequence homology with GmAREB1, S1AREB and ABF2. Quantitative real-time PCR analysis showed that AhAREB1 was induced by polyethylene...

Molecular cloning and characterization of a chlorophyll degradation regulatory gene from bamboo

Y. -X. Chen, Q. Wei, B. -K. Kuai, Y. -L. Ding

Biologia plantarum 57:63-69, 2013 | DOI: 10.1007/s10535-012-0139-6

Leaf senescence constituted the final stage of leaf development and it is always accompanied by the leaf yellowing. The non-yellowing gene (NYE1), initially identified from Arabidopsis in our laboratory, is a key regulatory gene responsible for chlorophyll degradation during senescence. In this study, an orthologue of AtNYE1 was isolated from the bamboo (Bambusa emeiensis cv. Viridiflavus) and tentatively named BeNYE1. The full length sequence of 1 386 bp contains an open reading frame of 801 bp. The protein encoded by BeNYE1 consists of 266 amino acids. Sequence analysis revealed that BeNYE1 had high similarity...

Two poplar calcineurin B-like proteins confer enhanced tolerance to abiotic stresses in transgenic Arabidopsis thaliana

D. -D. Li, X. -L. Xia, W. -L. Yin, H. -C. Zhang

Biologia plantarum 57:70-78, 2013 | DOI: 10.1007/s10535-012-0251-7

Calcium is a critical component in a number of plant signal transduction pathways and the calcineurin B-like protein (CBL) family is a unique group of calcium sensors regulating a family of CBL-interacting protein kinases (CIPKs). In this study, two poplar CBL genes, PeCBL6 (GenBank acc. No. DQ907710) and PeCBL10 (GenBank acc. No. DQ899956), were characterized in transgenic Arabidopsis thaliana, particularly with regard to its role in abiotic stress resistance. Expression of the two CBL genes in poplar was induced by cold, drought, or high salinity, but not by abscisic acid (ABA) treatment. In Arabidopsis thaliana,...

Molecular mapping of QTLs for wheat flag leaf senescence under water-stress

M. N. Barakat, L. E. Wahba, S. I. Milad

Biologia plantarum 57:79-84, 2013 | DOI: 10.1007/s10535-012-0138-7

A segregating population from the cross between drought sensitive (Variant-2) and drought tolerant (Cham-6) genotypes was made to identify molecular markers linked to wheat (Triticum aestivum L.) flag leaf senescence under water-stress. From 38 random amplified polymorphic DNA (RAPD) primers, 25 inter-simple sequence repeat (ISSR) primers and 46 simple sequence repeat (SRR) primers, tested for polymorphism among parental genotypes and F2 population. Quantitative trait locus (QTL) for flag leaf senescence was associated with 1 RAPD marker (Pr9), 4 ISSR markers (Pr8, AD5, AD2 and AD3), and 1 SSR marker (Xgwm382) and explained 44, 50, 35, 31, 22...

GmPOI gene encoding a Pollen_Ole_e_I conserved domain is involved in response of soybean to various stresses

W. W. Song, F. M. Duan, W. B. Li, Q. Lin, H. X. Zhou, X. Han, J. A. Wang

Biologia plantarum 57:85-90, 2013 | DOI: 10.1007/s10535-012-0258-0

In the previous research, a novel gene GmPOI (GenBank acc. No. HM235775) encoding a Pollen_Ole_e_I conserved domain was identified in roots of soybean drought resistant cv. Jindou 23. In the present study, GmPOI was cloned and functionally characterized. Real-time quantitative PCR indicated that the expression of GmPOI was induced by drought, cold, salt and abscisic acid in wild-type soybean. The soybean plants overexpressing GmPOI showed higher tolerance to drought stress than wild types. We concluded that GmPOI is probably a novel gene that is involved in the response to various stresses in soybean.

Ameliorative effect of melatonin on meristematic cells of chilled and re-warmed Vigna radiata roots

K. Szafrańska, S. Glińska, K. M. Janas

Biologia plantarum 57:91-96, 2013 | DOI: 10.1007/s10535-012-0253-5

Changes in ultrastructure of meristematic cells as well as growth and lipid peroxidation in roots of 3-d-old seedlings obtained from control (C), hydroprimed (H) and hydroprimed with melatonin (H-MEL) seeds after 2 d of incubation at 25 or 5 °C and 2 d of re-warming after chilling were investigated. Under 25 °C hydropriming (H and H-MEL) inhibited root growth, but after chilling and re-warming a positive MEL effect on root elongation was observed. The results show decreased lipid peroxidation in H-MEL roots already after chilling, but the significant extent of MEL impact was seen after re-warming. Similarly at the ultrastructural level, the protective...

Isolation and characterization of cold inducible genes in carrot by suppression subtractive hybridization

S. R. Kumar, S. Anandhan, S. Dhivya, A. Zakwan, R. Sathishkumar

Biologia plantarum 57:97-104, 2013 | DOI: 10.1007/s10535-012-0250-8

Daucus carota is cultivated widely but grows best in cool climates. Suppression subtractive hybridization (SSH) is a PCR based method used to selectively amplify differentially expressed cDNAs and simultaneously suppress non-target cDNA. A subtraction forward library was constructed using RNA isolated from the leaves of unstressed and cold stressed carrot plants to determine the genes upregulated during cold stress. Out of the hundreds of clones obtained, sequences of 41 promising clones were submitted to the NCBI EST database. Sequence analyses revealed that these genes have significant roles in signal transduction, osmolyte synthesis...

Accumulation of WCS120 and DHN5 proteins in differently frost-tolerant wheat and barley cultivars grown under a broad temperature scale

K. Kosová, P. Vítámvás, P. Prášilová, I. T. Prášil

Biologia plantarum 57:105-112, 2013 | DOI: 10.1007/s10535-012-0237-5

Proteins WCS120 and DHN5 are known as the major cold-inducible dehydrins in wheat and barley plants, respectively. WCS120 and DHN5 relative accumulation increased exponentially along with a growth temperature decline in the range from optimum to cold temperatures. Even at optimum growth temperatures, the most frost-tolerant wheat and barley cultivars can be distinguished from the remaining ones according to dehydrin relative accumulation. The highly tolerant wheat and barley cultivars started accumulating dehydrins at higher growth temperatures and reached higher dehydrin amounts than the less tolerant ones. Statistically significant correlations between...

Characterization of phospholipase D from Chorispora bungeana callus in response to freezing stress

N. Yang, X. L. Yue, H. Zhang, G. F. Wu, F. X. Ding, T. G. Zhang, L. Z. An

Biologia plantarum 57:113-120, 2013 | DOI: 10.1007/s10535-012-0259-z

The influence of freezing on phospholipase D (PLD) was studied in Chorispora bungeana Fisch. & C.A. Mey., which is a naturally cold-tolerant species. During the freezing treatment (-4 °C), PLD activities in both microsomal and mitochondrial membranes increased at day 3, remained at a high level at day 6 and then declined to a moderate level. The RT-PCR analyses showed that PLD activity partially corresponded to the CbPLD gene transcript level. The freezing treatment resulted in increases in the K _m and V _max for microsomal and mitochondrial PLD, respectively. Freezing injury, as measured by electrolyte...

Abscisic acid is required in transduction of cadmium signal to potato roots

A. Stroiński, K. Giżewska, M. Zielezińska

Biologia plantarum 57:121-127, 2013 | DOI: 10.1007/s10535-012-0135-x

Treatment of potato (Solanum tuberosum) plants with cadmium or abscisic acid (ABA) enhanced the content of StPCS 1 transcript and activity of phytochelatin synthase (PCS) in roots.transcript and activity of phytochelatin synthase (PCS) in roots. These treatments enhanced the contents of ABA and expression of genes coding 9-cis-epoxycarotenoid dioxygenase 1 (NCED1) and basic leucine zipper (b-ZIP).expression of genes coding 9-cis-epoxycarotenoid dioxygenase 1 (NCED1) and basic leucine zipper (b-ZIP). Simultaneous treatment of potato plants with Cd and fluridone (Flu), an inhibitor of ABA biosynthesis, completely...

Vanadium distribution in roots and leaves of Phaseolus vulgaris: morphological and ultrastructural effects

D. Saco, S. Martín, P. San José

Biologia plantarum 57:128-132, 2013 | DOI: 10.1007/s10535-012-0133-z

In different plant species, vanadium has been considered either as beneficial or as a toxic element, or even as secondary metabolism elicitor, but the mechanisms involved are still not completely understood. In this study, the responses of Phaseolus vulgaris L. cv. Contender roots and leaves to different vanadyl sulfate concentrations were studied. The plants grown hydroponically with V had thicker roots, a less developed main root, and a smaller number of secondary roots than the control plants. The V content in roots and leaves was correlated with V supply concentration but the V content in leaf was always much lower than in the root, which...

Variability for resistance to Fusarium solani culture filtrate and fusaric acid among somaclones in pea

J. Horáček, L. Švábová, P. Šarhanová, A. Lebeda

Biologia plantarum 57:133-138, 2013 | DOI: 10.1007/s10535-012-0131-1

Pea (Pisum sativum L.) somaclones of cultivars Adept, Komet and Bohatýr were obtained after selection in vitro with Fusarium solani filtrate and fusaric acid (FA). R2 regenerants were analysed by random amplification of polymorphic DNA (RAPD; OPAB4, P-14, UBC-556) and inter-retrotransposon amplification polymorphism (IRAP; Ogre) markers. Marker UBC-556 showed different banding patterns for each cultivar, but without specific bands for selected and control plants. Markers OPAB4, P14 and Ogre were useful for clear discrimination between selected and non-selected variants of all three cultivars. Flow cytometry analysis proved the...

The effect of elicitors on oleanolic acid accumulation and expression of triterpenoid synthesis genes in Gentiana straminea

Z. -J. Zhao, Y. -G. Song, Y. -L. Liu, M. Qiao, X. -L. Zhai, F. -N. Xiang

Biologia plantarum 57:139-143, 2013 | DOI: 10.1007/s10535-012-0260-6

Gentiana straminea is native to the Qinghai-Tibet plateau, where it is exposed to extremes of cold and strong UV-B radiation. Here we showed that low temperature, but not UV-B radiation, affected the accumulation of the triterpenoid oleanolic acid. Neither of these stresses altered the expression of known triterpenoid synthesis genes. However, the application of methyl jasmonate (MeJA), but not salicylic acid (SA), significantly enhanced the accumulation of oleanolic acid, and up-regulated the triterpenoid synthesis genes, especially the expression of βAS, the gene encoding β-amyrin.

Plasma membrane permeability as an indicator of salt tolerance in plants

M. M. F. Mansour

Biologia plantarum 57:1-10, 2013 | DOI: 10.1007/s10535-012-0144-9

There is evidence that the plasma membrane (PM) permeability alterations might be involved in plant salt tolerance. This review presents several lines of evidence demonstrating that PM permeability is correlated with salt tolerance in plants. PM injury and hence changes in permeability in salt sensitive plants is brought about by ionic effects as well as oxidative stress induced by salt imposition. It is documented that salinity enhances lipid peroxidation as well as protein oxidative damage, which in turn induces permeability impairment. PM protection, and thus retained permeability, in tolerant plants under salt imposition could be achieved through...

Recent advances in plant immunity: recognition, signaling, response, and evolution

S. Hou, C. Zhang, Y. Yang, D. Wu

Biologia plantarum 57:11-25, 2013 | DOI: 10.1007/s10535-012-0109-z

Innate immune system is employed by plants to defend against phytopathogenic microbes through specific perception of non-self molecules and subsequent initiation of resistance responses. Current researches elucidate that plants mostly rely on cell surface-located pattern recognition receptors (PRRs) and intracellular nucleotide-binding leucine-rich repeat proteins (NB-LRRs) to recognize pathogen-associated molecular patterns (PAMPs) and effector proteins from microbial pathogens, initiating PAMP- and effector-triggered immunity (PTI and ETI), respectively. Some pathogenic bacterial effector proteins are usually secreted into plant cells and play a...

Bassler, B.L., Lichten, M., Schüpbach, G. (ed): Annual Review of Genetics. Vol. 45.

J. Doležel

Biologia plantarum 57:199, 2013 | DOI: 10.1007/s10535-013-0302-8

Kůdela, V., Kocourek, F., Bárnet, M. (ed.): Czech and English Names of Plant Diseases and Pests.

J. Špak

Biologia plantarum 57:200, 2013 | DOI: 10.1007/s10535-013-0303-7

Wood ontogeny during ex vitro acclimatization in micropropagated hybrid poplar clones

A. Kaňuchová, J. Ďurkovič

Biologia plantarum 57:144-148, 2013 | DOI: 10.1007/s10535-012-0122-2

Wood ontogeny patterns were determined during the ex vitro acclimatization period in micropropagated plantlets of hybrid poplar clones T-14 [Populus tremula × (Populus × canescens)] and T-50 [(Populus × canescens) × Populus tremula]. The temporal course of developmental changes in the woody tissue was characterized on a weekly basis starting from the day of transfer to the ex vitro environment until full acclimatization was achieved on day 28. In vitro rooted plantlets had already initiated lignification of secondary xylem cells. The greatest increase in the amount of woody tissue was observed...

Lipid profiling and tolerance to low-temperature stress in Thellungiella salsuginea in comparison with Arabidopsis thaliana

X. D. Zhang, R. P. Wang, F. J. Zhang, F. Q. Tao, W. Q. Li

Biologia plantarum 57:149-153, 2013 | DOI: 10.1007/s10535-012-0137-8

Changes in membrane lipid composition is a fundamental strategy for plants to resist low-temperature stress. We compared members of 11 membrane glycerolipid classes in Thellungiella salsuginea and its close relative Arabidopsis thaliana at normal growth temperature, and during cold acclimation (CA), freezing (FR), and post-freezing recovery (PFR). The results showed several properties of T. salsuginea distinct from that in A. thaliana, which included: 1) low relative content of phosphatidic acid (PA) and a rapid increase and decrease of PA during FR and PFR respectively; 2) insensitivity of lyso-phospholipids...

Brassinosteroid regulates secondary metabolism in tomato towards enhanced tolerance to phenanthrene

G. J. Ahammed, Y. H. Zhou, X. J. Xia, W. H. Mao, K. Shi, J. Q. Yu

Biologia plantarum 57:154-158, 2013 | DOI: 10.1007/s10535-012-0128-9

We investigated the role of 24-epibrassinolide (EBR) in the amelioration of phenanthrene (PHE) stress in tomato (Solanum lycopersicum L.). Exposure to PHE (300 μM) significantly decreased shoot and root length (19 and 16 %, respectively), fresh mass (35 and 43 %, respectively), contents of chlorophyll a (26 %), chlorophyll b (27 %) and carotenoids (18 %) in tomato plants. In addition, PHE increased the malondialdehyde (MDA) content (57 %) and activity of secondary metabolism related enzymes glutathione-S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PDH), shikimate dehydrogenase (SKDH), phenylalanine ammonia-lyase...

Water deficit and recovery response of Medicago truncatula plants expressing the ELIP-like DSP22

S. S. Araújo, A. S. Duque, J. M. Silva, D. Santos, A. B. Silva, P. Fevereiro

Biologia plantarum 57:159-163, 2013 | DOI: 10.1007/s10535-012-0235-7

In this article, we present the response of Medicago truncatula Gaert. cv. Jemalong plants expressing constitutively the Dsp22 gene from Craterostigma plantagineum to water stress and rehydration. The Dsp22 gene encodes an ELIP-like protein thought to protect the chloroplast against photooxidative damage during the dehydration and rehydration. The Dsp22 transgenic homozygous M. truncatula plants showed higher amount of chlorophyll (Chl), lower Chl a/Chl b ratio and higher actual efficiency of energy conversion in photosystem 2 (Φ_PSII) after rehydration, when compared to the wild...

Thidiazuron and silver nitrate enhanced gynogenesis of unfertilized ovule cultures of Cucumis sativus

J. W. Li, S. W. Si, J. Y. Cheng, J. X. Li, J. Q. Liu

Biologia plantarum 57:164-168, 2013 | DOI: 10.1007/s10535-012-0269-x

Gynogenesis of Chinese long cucumber (Cucumis sativus L.) was obtained from unpollinated ovules cultured on cucumber basal medium (CBM) supplemented with thidiazuron (TDZ) and in some experiments AgNO₃. High induction frequencies (7.85-12.14 %) were induced from unpollinated ovules at the time of anthesis at 0.03-0.07 mg dm^-3 TDZ. Histological analysis indicated that embryo sacs developed completely at the time of anthesis. Further, the highest plant regeneration rate was achieved at CBM supplemented with 0.05 mg dm^-3 a-naphthaleneacetic acid, 0.2 mg dm^-3 6-benzyladenine and 5-10 mg dm^-3...

Progesterone moderates damage in Arabidopsis thaliana caused by infection with Pseudomonas syringae or P. fluorescens

A. Janeczko, I. Tóbiás, A. Skoczowski, F. Dubert, G. Gullner, B. Barna

Biologia plantarum 57:169-173, 2013 | DOI: 10.1007/s10535-012-0142-y

Brassinosteroids are known to protect plants against various abiotic and biotic stresses, however, very limited information is available about the role of progesterone. Therefore the effects of Pseudomonas syringae pv. syringae (P.s.) wild type strain 61, its hrcC mutant, and the saprophytic P. fluorescens (P.f.) strain 55 were investigated in wild type Arabidopsis thaliana cv. Columbia and its rbohF knock-out mutant, with and without progesterone pre-treatment. The reactions of wild type and rbohF mutant Arabidopsis to bacterial inoculations were similar, although 2 h after injection...

The role of cytokinins during micropropagation of wych elm

J. Malá, P. Máchová, H. Cvrčková, M. Karady, O. Novák, J. Mikulík, J. Dostál, M. Strnad, K. Doležal

Biologia plantarum 57:174-178, 2013 | DOI: 10.1007/s10535-012-0252-6

We have compared the influence of two aromatic cytokinin derivatives, N ⁶-benzyladenine (BA) and meta-topolin (mT), on the in vitro multiplication and senescence of wych elm (Ulmus glabra Huds.). After 3 months of cultivation, the micropropagation rate was higher (approx. six times more shoots developed) on Murashige and Skoog (MS) medium supplemented with mT than on MS supplemented with BA. Quantification of 50 endogenous cytokinins, using a recently developed UPLC-ESI(+)-MS/MS method, showed significant differences in the cytokinin metabolites (especially different glucosides) in explants cultivated on media...

Ectopic expression of the Osmyb4 rice gene enhances synthesis of hydroxycinnamic acid derivatives in tobacco and clary sage

T. Docimo, M. Mattana, R. Fasano, R. Consonni, N. de Tommasi, I. Coraggio, A. Leone

Biologia plantarum 57:179-183, 2013 | DOI: 10.1007/s10535-012-0257-1

In this work, we report the ectopic expression of the Osmyb4 rice gene, encoding the Myb4 transcription factor, in Nicotiana tabacum and Salvia sclarea. Transcriptional analysis of T₂ homozygous tobacco plants overexpressing Osmyb4 revealed that Myb4 activated the transcription of several genes of the phenylpropanoid pathway such as PAL, C4H, 4CL1, 4CL2 (encoding phenylalanine ammonia-lyase, cinnamic acid 4-hydroxylase, 4-coumarate: Co A ligase1, 4-coumarate: Co A ligase2). Moreover, the Myb4 increased expression of HQT encoding hydroxycinnamoyl-CoA: quinate transferase, which specifically triggers...

Frost tolerance in winter wheat cultivars: different effects of chromosome 5A and association with microsatellite alleles

G. Ganeva, T. Petrova, S. Landjeva, E. Todorovska, S. Kolev, G. Galiba, F. Szira, A. F. Bálint

Biologia plantarum 57:184-188, 2013 | DOI: 10.1007/s10535-012-0267-z

Frost tolerance of ten Bulgarian winter wheat (Triticum aestivum L.) cultivars (Milena, Pobeda, Sadovo-1, Enola, Kristal, Laska, Svilena, Russalka, No301 and Lozen) and five foreign cultivars (Mironovskaya 808, Bezostaya-1, Rannaya-12, Skorospelka-35 and Chinese Spring) was studied in two experimental seasons following natural cold acclimation and in one experiment carried out in controlled acclimation conditions. Considerable intercultivar variability in plant survival was observed after freezing at -21 °C following sufficient cold acclimation, or at -18 °C following insufficient or controlled acclimation. In seven cultivars, the effects of...

Dark preincubation improves shoot organogenesis from Rhodiola crenulata leaf explants

Y. Zhao, A. R. Stiles, P. K. Saxena, C. Z. Liu

Biologia plantarum 57:189-192, 2013 | DOI: 10.1007/s10535-012-0261-5

An efficient in vitro plant regeneration system has been developed using dark preincubated leaf explants of Rhodiola crenulata, a traditional Tibetan medicinal plant. The leaf explants, preincubated in the dark for 5 d, developed an average of 9.1 shoots per explant on a medium containing 15 μM N ⁶-benzyladenine (BA) and 2.5 μM gibberellic acid (GA₃). The biochemical mechanism underlying dark-induced shoot organogenesis was investigated by measuring polyphenol oxidase (PPO) activity. Dark preincubation significantly reduced PPO activity in leaf explants during the initial period of shoot organogenesis...

Aquaporin expression during seed osmopriming and post-priming germination in spinach

K. Chen, A. Fessehaie, R. Arora

Biologia plantarum 57:193-198, 2013 | DOI: 10.1007/s10535-012-0266-0

Aquaporins (AQPs) are proteinaceous channels known to regulate transmembrane water transport, and therefore may be important component of imbibition during osmopriming and germination. To explore the association between AQPs and osmopriming-led enhanced germination performance, we studied the expression patterns of four spinach (Spinacia oleracea) AQP coding genes (SoPIP1;1, SoPIP1;2, SoPIP2;1, and SoδTIP) during osmopriming and subsequent germination under optimal conditions, chilling and drought. All these genes were up-regulated within 2-4 d of priming (phase II-imbibition). We hypothesize such up-regulation...