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Plant growth-promoting rhizobacteria are known to associate with several cereal crops. The rhizobacterium exerts its function by synthesizing diverse arrays of phytohormones, such as cytokinin (Ck). However, it is difficult to determine the plant growth promotion when a bacterium produces many different kinds of phytohormones. Therefore, to assess the involvement of Ck in growth promotion and activation of antioxidant and physiological systems, we set up this experiment. Wheat seeds (Triticum aestivum L.) were inoculated with Azospirillum brasilense RA-17 (which produces zeatin type Ck) and RA-18 (which failed to produce Ck). Results showed that seed inoculation with RA-17 significantly improved growth and yield-related parameters compared with RA-18. The activity of enzymes, proline contents, and endogenous hormonal levels in wheat kernels were improved considerably with RA-17 than with RA-18. Strain RA-17 enhanced grain assimilation more than strain RA-18 resulting in a higher crop yield. These results suggest that microbial Ck production may be necessary for stimulating plant growth promotion and activating antioxidant and physiological systems in wheat.
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Due to increased industrialization, arsenic (As) in the soil has become a serious issue for wheat production since past few decades. We investigated the role of Azospirillum brasilense and trans-zeatin riboside (tZR) in the mitigation of arsenic toxicity in wheat for 2 years (2018-2019 and 2019-2020) in pot experiments. Wheat plants grown in soil artificially spiked with arsenic (50, 70, and 100 µM) was left alone or amended with A. brasilense, tZR, or their combination as mitigation strategies. A treatment without arsenic or amendments was maintained as control. Arsenic-induced physiological damages were noticed in the wheat plants. Detrimental effects on the plant physiological functions, such as disruption of cell membrane stability, reduced water uptake, and stomatal functions, were noticed with increase in As toxicity. Application of biological amendments reversed the effects of As toxicity by increasing wheat plant growth rate, leaf area, and photosynthesis and also yield. Therefore, application of tZR and wheat seed inoculation with A. brasilense could be a sustainable and environmentally friendly strategy to mitigate arsenic-induced crop physiological damages.
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Arsénico , Azospirillum brasilense , Arsénico/metabolismo , Isopenteniladenosina/análogos & derivados , Raíces de Plantas/metabolismo , Suelo , TriticumRESUMEN
ABSTRACT Three parasitoid species Aphidius colemani, Aphidius matricariae (Hymenoptera: Braconidae) and Aphelinus abdominalis (Hymenoptera: Aphelinidae) were evaluated concerning their parasitism potential in two aphid species, Aphis glycines and Aphis gossypii (Hemiptera: Aphididae). The feeding of these two aphid species, even at low sums, can significantly damage photosynthesis and is found to transmit many kinds of plant viruses, which impact potential adverse effects on the plants. The overall parasitization on all nymphal ages in As. glycines was accomplished by Ad. colemani (60.50%), Ad. matricariae (49.16%) and Al. abdominalis (40%), while in As. gossypii parasitism exhibited by Ad. colemani (79.48%), Ad. matricariae (65.33%) and Al. abdominalis (58.83%). Aphelinus abdominalis exhibited the lowest parasitism in both given species as hosts. Significant differences in parasitism of different parasitoids and host species were observed. Concerning the preference of nymphal instars, we found that parasitoids species prefer to parasitize 1st- 4th instars in As. gossypii while in As. glycines 2nd, 1st, 3rd and 4th. Our results showed that the parasitism increases with the increase of parasitoid numbers and hosts densities.
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Empowerment of wheat genotypes by application of growth regulators, compatible solutes and plant extracts under water restriction is an important strategy for getting sustainable yield. This study aimed to evaluate the effects of drought stress on the growth and yield of wheat genotypes and also monitor and compare the role of ABA, SA as well as moringa and mulbery leaf water extracts in improving drought tolerance of wheat genotypes. The work was performed at the research area of the Faculty of Agricultural Sciences, Ghazi University, Dera Ghazi Khan, Pakistan. Three wheat cultivars Aas-2011, Faisalabad- 2008 and Triple dwarf-1 were subjected to drought stress (skipping the irrigation at grain filling stage). The wheat genotypes were subjected to treatments viz., T1 i.e. All normal irrigation without application of abscisic acid (ABA), salicylic acid (SA), moringa (MLE) and mulberry leaf water extract (MBLE), T2 i.e. skipping the irrigation at grain filling stage and application of 2µM ABA, T3 i.e. skipping the irrigation at grain filling stage and application of 10 m mol SA, T4 i.e. skipping the irrigation at grain filling stage and application of 15% MLE and T5 i.e. skipping the irrigation at grain filling stage and application of 10% MBLE. The experiment was laid out in Randomized Complete Block Design with factorial arrangement and repeated three times. From this study it is concluded that Aas-2011 shown best result under drought condition by applying growth regulators and plant water extracts.
O fortalecimento de genótipos de trigo pela aplicação de reguladores de crescimento, solutos compatíveis e extratos vegetais sob restrição hídrica é uma importante estratégia para obtenção de produção sustentável. Trilha de campo foi realizada na área de pesquisa da Faculdade de Ciências Agrárias, Universidade de Ghazi, Dera Ghazi Khan, Paquistão. Três cultivares de trigo Aas-2011, Faisalabad-2008 e Triple anão-1 foram submetidas a estresse hídrico (pulando a irrigação no estágio de enchimento de grãos). Os genótipos de trigo foram submetidos a tratamentos, T1, ou seja, irrigação normal sem aplicação de ácido abscísico (ABA), ácido salicílico (SA), moringa (MLE) e extrato de água de amoreira (MBLE), T2¬, pular a irrigação em estágio de enchimento de grãos e aplicação de ABA 2µM, T3 ou seja, ignorando a irrigação no estágio de enchimento de grãos e aplicação de 10 m mol SA, T4 ou seja, ignorando a irrigação no estágio de enchimento de grãos e aplicação de 15% MLE e T5 ou seja, ignorando a irrigação no enchimento de grãos estágio e aplicação de 10% MBLE. O experimento foi exposto no delineamento de blocos completos casualizados com arranjo fatorial e repetido três vezes. A partir deste estudo conclui-se que Aas-2011 apresentou melhor resultado sob condição de seca, aplicando reguladores de crescimento e extratos de água de plantas.
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Reguladores del Crecimiento de las Plantas , Triticum , Moringa , Deshidratación , MorusRESUMEN
Aims: Coronary lesions precursors of acute events remain elusive, since they undergo continuous changes and their temporal changes are not very well-characterized. In natural history studies, optical frequency domain imaging (OFDI) has been used only to assess fibroatheromas as a 2D structure and sometimes in a single frame fashion. We aim at describing the serial volumetric modifications of the fibrous cap (FC) of the fibroatheromas as determined by OFDI over a 6-month follow-up period. Methods and results: In 49 patients, OFDI investigation was performed following treatment of culprit lesion and at 6-month follow-up in patients with ST-segment elevation myocardial infarction (STEMI). A fully automatic volumetric quantification of FC was done in all lipid-containing frames of non-culprit lesions in the infarct related artery. These lesions were matched at baseline and 6-month follow-up. A total of 58 non-culprit lipid rich lesions (34 TCFAs and 24 thick-cap fibroatheroma [ThCFA]) were found in 34 patients at baseline. Overall, there was a FC volume decrease of 1.57 (Inter-quartile Range [IQR] -4.13 to 0.54) mm3 at 6-months. 27% of the lesions changed their phenotype over time (TCFA or ThCFA). TCFAs that became ThCFAs at follow-up had smaller mean and maximal FC as compared with lesions that remained TCFAs (P = 0.01 for both). Conclusions: Non-culprit fibroatheromas located in the infarct related artery of patients with STEMI had a volumetric reduction of the FC after 6-month follow-up. Quantitative FC assessment was able to differentiate high-risk lesions that became ThCFAs. There was a considerable change of plaque phenotype (TCFAs or ThCFAs) over time.
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Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Placa Aterosclerótica/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/terapia , Trombectomía/métodos , Tomografía de Coherencia Óptica/métodos , Anciano , Terapia Combinada , Enfermedad de la Arteria Coronaria/terapia , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea , Placa Aterosclerótica/cirugía , Estudios Prospectivos , Medición de Riesgo , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/mortalidad , Tasa de Supervivencia , Factores de Tiempo , Resultado del TratamientoRESUMEN
Aims: Newer-generation drug-eluting stents (DES) have been shown to be superior to first-generation DES. Current-generation DES have zotarolimus, everolimus or biolimus as antiproliferative drugs. Novolimus, a metabolite of sirolimus, has been specifically developed to provide efficacy similar to currently available agents at a lower dose and thus requires a lower polymer load. We report the final five-year outcomes of the EXCELLA II trial comparing a zotarolimus-eluting stent (ZES) with a novolimus-eluting stent (NES).Methods and results: EXCELLA II is a prospective, multicentre, single-blind, non-inferiority clinical trial. Patients (n=210) with a maximum of two de novo lesions in two different epicardial vessels were randomised (2:1) to treatment with either NES (n=139) or ZES (n=71). At five-year follow-up, patients in the NES group had a significantly lower incidence of the patient-oriented (HR 0.53, 95% CI: 0.32-0.87, p=0.013) and device-oriented (HR 0.38, 95% CI: 0.17-0.83, p=0.011) composite endpoints. There was no difference in cardiac death and definite/probable stent thrombosis between the two groups; however, there was a trend towards reduction in myocardial infarction and repeat revascularisation in the NES group at five-year follow-up.Conclusions: At five-year follow-up, the incidence of device- and patient-oriented events was significantly lower in the NES group. Further studies, adequately powered for clinical outcomes, are warranted. Trial Registration: ClinicalTrials.gov number NCT00792753.
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Everolimus , Stents Liberadores de FármacosRESUMEN
Current generation of drug-eluting stents has significantly improved the outcomes of percutaneous coronary intervention by substantially reducingin-stent restenosis and stent thrombosis. However, a potential limitation of these stents is the permanent presence of a metallic foreign bodywithin the artery, which may cause vascular inflammation, restenosis, thrombosis, and neoatherosclerosis. The permanent stents also indefinitelyimpair the physiological vasomotor function of the vessel and future potential of grafting the stented segment. Bioresorbable scaffolds (BRSs) havethe potential to overcome these limitations as they provide temporary scaffolding and then disappear, liberating the treated vessel from its cageand restoring pulsatility, cyclical strain, physiological shear stress, and mechanotransduction. While a numberof BRSs are under development, twodevices with substantial clinical data have already received a Conformite´ Europe´enne marking. This review article presents the current status ofthese devices and evaluates the challenges that need to be overcome before BRSs can become the workhorse device in coronary intervention.
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Angioplastia , Enfermedad de la Arteria Coronaria , Stents Liberadores de FármacosRESUMEN
Aims: Bioresorbable scaffolds are increasingly used in patients with coronary artery disease undergoing percutaneouscoronary interventions. ABSORB EXTEND is an ongoing study that will recruit 800 patients. Thisreport evaluates acute and late scaffold failure in the first 450 patients enrolled in ABSORB EXTEND whohave completed 12 months follow-up.Methods and results: Clinical event data from the first 450 patients enrolled in ABSORB EXTEND havedemonstrated low rates of ischaemia-driven MACE (4.2%) and target vessel failure (4.7%) at 12 months.There have been seven cases of device failure in this study: three cases of scaffold dislodgement (0.67%) andfour cases of subacute or late scaffold thrombosis (0.89%). All scaffold dislodgements occurred in the leftcircumflex (LCX), and in two cases dislodgement was observed after reinsertion of the same device. Twocases of subacute scaffold thrombosis and two late scaffold thromboses were observed. Two out of four casesof scaffold thrombosis seemed to be related to either premature discontinuation of dual antiplatelet therapy(DAPT) or resistance to clopidogrel.Conclusions: This is the first report specifically describing the incidence and the potential mechanisms ofscaffold dislodgement and scaffold thrombosis as seen in the ABSORB EXTEND trial.