Improvement of regeneration in pepper: a recalcitrant species

[EN] Organogenesis is influenced by factors like genotype, type of explant, culture medium components, and incubation conditions. The influence of ethylene, which can be produced in the culture process, can also be a limiting factor in recalcitrant species like pepper. In this work, bud induction was achieved from cotyledons and hypocotyls-from eight pepper cultivars-on Murashige and Skoog (MS) medium supplemented with 22.2 mu M 6-benzyladenine (6BA) and 5.71 mu M indole-3-acetic acid (IAA), in media with or without silver nitrate (SN) (58.86 mu M), a suppressor of ethylene action. In the SN-supplemented medium, the frequencies of explants with buds and with callus formation were lower in both kinds of explant, but higher numbers of developed shoots were isolated from explants cultured on SN. Bud elongation was better in medium with gibberellic acid (GA(3)) (2.88 mu M) than in medium free of growth regulators or supplemented with 1-aminocyclopropane-1-carboxylic acid (ACC) at 34.5 mu M. However, isolation of shoots was difficult and few plants were recovered. The effect of adding SN following bud induction (at 7 d) and that of dark incubation (the first 7 d of culture) was also assessed in order to improve the previous results. When SN was added after bud induction, similar percentages of bud induction were found for cotyledons (average frequency 89.37% without SN and 94.37% with SN) whereas they doubled in hypocotyls (50% without SN and 87.7% with SN). In addition, in both kinds of explant, the number of developed plants able to be transferred to soil (developed and rooted) was greatly increased by SN. Dark incubation does not seem to improve organogenesis in pepper, and hypocotyl explants clearly represent a better explant choice-with respect to cotyledonary explants-for the pepper cultivars assayed.We thank the COMAV germplasm bank at Universitat Politecnica de Valencia and the Arid Lands Institute for pepper seeds and the Tunisian Ministry of Higher Education and Scientific Research who fund N. Gammoudi's stay.Gammoudi, N.; San Pedro-Galan, T.; Ferchichi, A.; Gisbert Domenech, MC. (2018). Improvement of regeneration in pepper: a recalcitrant species. In Vitro Cellular & Developmental Biology - Plant. 54(2):145-153. https://doi.org/10.1007/s11627-017-9838-1S145153542Ashrafuzzaman M, Hossain MM, Razi Ismail M, Shahidul Haque M, Shahidullah SM, Uz Zaman S (2009) Regeneration potential of seedling explants of chilli (Capsicum annuum). Afr J Biotechnol 8:591–596Bortesi L, Fischer R (2015) The CRISPR/Cas9 system for plant genome editing and beyond. Biotechnol Adv 33:41–52Brooks C, Nekrasov V, Lippman ZB, Van Eck J (2014) Efficient gene editing in tomato in the first generation using the clustered regularly interspaced short palindromic repeats/CRISPR-associated9 system. Plant Physiol 166:1292–1297Brown DC, Thorpe TA (1995) Crop improvement through tissue culture. World J Microbiol Biotechnol 11:409–415Carvalho MAF, Paiva R, Stein VC, Herrera RC, Porto JMP, Vargas DP, Alves E (2014) Induction and morpho-ultrastructural analysis of organogenic calli of a wild passion fruit. Braz Arch Biol Technol 57:581–859Christopher T, Rajam MV (1996) Effect of genotype, explant and medium on in vitro regeneration of red pepper. Plant CellTiss Org Cult 46:245–250Dabauza M, Peña L (2001) High efficiency organogenesis in sweet pepper (Capsicum annuum L.) tissues from different seedling explants. Plant Growth Regul 33:221–229De Filippis LF (2014) Crop improvement through tissue culture. In: Ahmad P, Wani MR, Azooz MM, Tran LSP (eds) Improvement of crops in the era of climate changes, vol 1. Springer, New York, pp 289–346Gammoudi N, Ben Yahia L, Lachiheb B, Ferchichi A (2016) Salt response in pepper (Capsicum annuum L.): components of photosynthesis inhibition, proline accumulation and K+/Na+ selectivity. JJ Aridland Agri 2:1–12González A, Arigita L, Majada J, Sánchez Tamés R (1997) Ethylene involvement in in vitro organogenesis and plant growth of Populus tremula L. Plant Growth Regul 22:1–6Grozeva S, Rodeva V, Todorova V (2012) In vitro shoot organogenesis in Bulgarian sweet pepper (Capsicum annuum L.) varieties. EJBio 8:39–44Gunay AL, Rao PS (1978) In vitro plant regeneration from hypocotyls and cotyledon explants of red pepper (Capsicum). Plant Sci Lett 11:365–372Huxter TJ, Thorpe TA, Reid DM (1981) Shoot initiation in light- and dark-grown tobacco callus: the role of ethylene. Physiol Plant 53:319–326Hyde CL, Phillips GC (1996) Silver nitrate promotes shoot development and plant regeneration of chile pepper (Capsicum annuum L.) via organogenesis. In Vitro-Plant 32:72–80Kothari SL, Joshi A, Kachhwaha S, Ochoa-Alejo N (2010) Chilli peppers—a review on tissue culture and transgenesis. Biotechnol Adv 28:35–48Kumar AO, Rupavathi T, Tata SS (2012) Adventitious shoot bud induction in chili pepper (Capsicum annuum L. cv. X-235). In J Sci Nat 3:192–196Kumar PP, Lakshmanan P, Thorpe TA (1998) Regulation of morphogenesis in plant tissue culture by ethylene. In Vitro Cell Dev Biol Plant 34:94–103Liu W, Parrott WA, Hildebrand DF, Collins GB, Williams EG (1990) Agrobacterium induced gall formation in bell pepper (Capsicum annuum L.) and formation of shoot-like structures expressing introduced genes. Plant Cell Rep 9:360–364Maligeppagol M, Manjula R, Navale PM, Babu KP, Kumbar BM, Laxman RH (2016) Genetic transformation of chilli (Capsicum annuum L.) with Dreb1A transcription factor known to impart drought tolerance. Indian J Biotechnol 15:17–24Mantiri FR, Kurdyukov S, Chen SK, Rose RJ (2008) The transcription factor MtSERF1 may function as a nexus between stress and development in somatic embryogenesis in Medicago truncatula. Plant Signal Behav 3:498–500Mezghani N, Jemmali A, Elloumi N, Gargouri-Bouzid R, Kintzios S (2007) Morpho-histological study on shoot bud regeneration in cotyledon cultures of pepper (Capsicum annuum). Biologia 62:704–710Mohamed-Yasseen Y (2001) Influence of agar and activated charcoal on uptake of gibberellin and plant morphogenesis in vitro. In Vitro Cell Dev Biol - Plant 37:204–205Moshkov IE, Novikova GV, Hall MA, George EF (2008) Plant growth regulators III: ethylene. In: George EF, Hall MA, Klerk G-JD (eds) Plant propagation by tissue culture, vol 1, 3rdedn. Springer, Dordrecht, The Netherlands, pp 239–248Murashige T, Skoog F (1962) A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol Plant 15:473–497Nogueira RC, Paiva R, de Oliveira LM, Soares GA, Soares FP, Castro AHF, Paiva PDO (2007) Calli induction from leaf explants of murici-pequeno (Byrsonima intermedia A. Juss.) Ciênc Agrotec 31:366–370Ochoa-Alejo N, Ramirez-Malagon R (2001) In vitro chili pepper biotechnology. In Vitro Cell Devl Biol Plant 37:701–729Orlińska M, Nowaczy P (2015) In vitro plant regeneration of 4 Capsicum spp. genotypes using different explant types. Turk J Biol 39:60–68Reid MS (1995) Ethylene in plant growth, development and senescence. In: Davies PJ (ed) Plant hormones: physiology, biochemistry and molecular biology, 2nd edn. Kluwer Acad Publ, Dordrecht, The Netherlands, pp 486–508Sanatombi K, Sharma GJ (2008) In vitro plant regeneration in six cultivars of Capsicum spp. using different explants. Biol Plant 52:141–145Santana-Buzzy N, Canto-Flick A, Barahona-Pérez F, Montalvo-Peniche MC, Zapata-Castillo PY, Solís-Ruiz A, Zaldívar-Collí A, Gutiérrez-Alonso O, Miranda-Ham ML (2005) Regeneration of habanero pepper (Capsicum chinense Jacq.) via organogenesis. Hortscience 40:1829–1831Santana-Buzzy N, Canto-Flick A, Iglesias-Andreu LG, Montalvo-Peniche MC, López-Puc G, Barahona-Pérez F (2006) Improvement of in vitro culturing of habanero pepper by inhibition of ethylene effects. Hortscience 41:405–409Sawai S, Ohyama K, Yasumoto S, Seki H, Sakuma T, Yamamoto T, Takebayashi Y, Kojima M, Sakakibara H, Aoki T, Muranaka T, Saito K, Umemoto N (2014) Sterol side chain reductase 2 is a key enzyme in the biosynthesis of cholesterol, the common precursor of toxic steroidal glycoalkaloids in potato. Plant Cell 26:3763–3774Shah SH, Ali S, Jan SA, Din J, Ali GM (2014) Assessment of silver nitrate on callus induction and in vitro shoot regeneration in tomato (Solanum lycopersicum Mill.) Pakistan J Bot 46:2163–2172Steinitz B, Wolf D, Matzevitch-Josef T, Zelcer A (1999) Regeneration in vitro and genetic transformation of pepper (Capsicum spp.): the current state of the art. Capsicum Eggplant Plant Newsletter 18:9–15Tamimi SM (2015) Effects of ethylene inhibitors, silver nitrate (AgNO3), cobalt chloride (CoCl2) and aminooxyacetic acid (AOA), on in vitro shoot induction and rooting of banana (Musa acuminata L.) Afr J Biotechnol 14:2510–2516Trujillo-Moya C, Gisbert C (2012) The influence of ethylene and ethylene modulators on shoot organogenesis in tomato. Plant Cell Tissue Organ Cult 111:41–48Yasmin S, Mensuali-Sodi A, Perata P, Pucciariello C (2014) Ethylene influences in vitro regeneration frequency in the FR13A rice harbouring the SUB1A gene. Plant Growth Reg 72:97–103Zhao Y, Stiles AR, Saxena PK, Liu CZ (2013) Dark preincubation improves shoot organogenesis from Rhodiola crenulata leaf explants. Biol Plant 57:189–19

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured

Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

Measurement of the production of a W boson in association with a charm quark in pp collisions at √s = 7 TeV with the ATLAS detector

The production of a W boson in association with a single charm quark is studied using 4.6 fb−1 of pp collision data at s√ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26−0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ(W + +c¯¯)/σ(W − + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s−s¯¯¯ quark asymmetry

Decreased surfactant phosphatidylcholine synthesis in neonates with congenital diaphragmatic hernia during extracorporeal membrane oxygenation

Purpose: Congenital diaphragmatic hernia (CDH) may result in severe respiratory insufficiency with a high morbidity. The role of a disturbed surfactant metabolism in the pathogenesis of CDH is unclear. We therefore studied endogenous surfactant metabolism in the most severe CDH patients who required extracorporeal membrane oxygenation (ECMO). Methods: Eleven neonates with CDH who required ECMO and ten ventilated neonates without significant lung disease received a 24-h infusion of the stable isotope [U-13C] glucose. The13C-incorporation into palmitic acid in surfactant phosphatidylcholine (PC) isolated from serial tracheal aspirates was measured. Mean PC concentration in epithelial lining fluid (ELF) was measured during the first 4 days of the study. Results: Fractional surfactant PC synthesis was decreased in CDH-ECMO patients compared to controls (2.4 ± 0.33 vs. 8.0 ± 2.4%/day, p = 0.04). The control group had a higher maximal enrichment (0.18 ± 0.03 vs. 0.09 ± 0.02 APE, p = 0.04) and reached this maximal enrichment earlier (46.7 ± 3.0 vs. 69.4 ± 6.6 h, p = 0.004) compared to the CDH-ECMO group, which reflects higher and faster precursor incorporation in the control group. Surfactant PC concentration in ELF was similar in both groups. Conclusion: These results show that CDH patients who require ECMO have a decreased surfactant PC synthesis, which may be part of the pathogenesis of severe pulmonary insufficiency and has a negative impact on weaning from ECMO

Search for the neutral Higgs bosons of the minimal supersymmetric standard model in pp collisions at root s=7 TeV with the ATLAS detector

A search for neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) is reported. The analysis is based on a sample of proton-proton collisions at a centre-of-mass energy of 7TeV recorded with the ATLAS detector at the Large Hadron Collider. The data were recorded in 2011 and correspond to an integrated luminosity of 4.7 fb-1 to 4.8 fb-1. Higgs boson decays into oppositely-charged muon or τ lepton pairs are considered for final states requiring either the presence or absence of b-jets. No statistically significant excess over the expected background is observed and exclusion limits at the 95% confidence level are derived. The exclusion limits are for the production cross-section of a generic neutral Higgs boson, φ, as a function of the Higgs boson mass and for h/A/H production in the MSSM as a function of the parameters mA and tan β in the mhmax scenario for mA in the range of 90GeV to 500 GeV. Copyright CERN

Decreased surfactant phosphatidylcholine synthesis in neonates with congenital diaphragmatic hernia during extracorporeal membrane oxygenation

Purpose: Congenital diaphragmatic hernia (CDH) may result in severe respiratory insufficiency with a high morbidity. The role of a disturbed surfactant metabolism in the pathogenesis of CDH is unclear. We therefore studied endogenous surfactant metabolism in the most severe CDH patients who required extracorporeal membrane oxygenation (ECMO). Methods: Eleven neonates with CDH who required ECMO and ten ventilated neonates without significant lung disease received a 24-h infusion of the stable isotope [U-13C] glucose. The13C-incorporation into palmitic acid in surfactant phosphatidylcholine (PC) isolated from serial tracheal aspirates was measured. Mean PC concentration in epithelial lining fluid (ELF) was measured during the first 4 days of the study. Results: Fractional surfactant PC synthesis was decreased in CDH-ECMO patients compared to controls (2.4 ± 0.33 vs. 8.0 ± 2.4%/day, p = 0.04). The control group had a higher maximal enrichment (0.18 ± 0.03 vs. 0.09 ± 0.02 APE, p = 0.04) and reached this maximal enrichment earlier (46.7 ± 3.0 vs. 69.4 ± 6.6 h, p = 0.004) compared to the CDH-ECMO group, which reflects higher and faster precursor incorporation in the control group. Surfactant PC concentration in ELF was similar in both groups. Conclusion: These results show that CDH patients who require ECMO have a decreased surfactant PC synthesis, which may be part of the pathogenesis of severe pulmonary insufficiency and has a negative impact on weaning from ECMO