RESUMEN
Climate change, water scarcity, population growth, and food shortage are some of the threatening challenges being faced in today's world. Among different types of stresses, drought stress presents a persistent challenge for global food production, however, its harshness and intensity are supposed to expand in the imminent future. The most striking effects of drought stress on plants are stunted growth, severe damage to photosynthetic apparatus, reduction in photosynthesis, reduction in seed germination, and nutrient uptake. To deal with the destructive effect of drought stress on plants, it is necessary to consider its effects, mechanisms of action, the agronomic and genetic basis for sustainable management. Therefore, there is an urgent need for sustainable solutions to cope up with the negative impact of drought stress. This review focuses on the detrimental effects of drought stress on plants' morphological, physiological, and biochemical characteristics and recommends suitable drought management techniques to reduce the severity of drought stress. We summarize the effect of drought stress on physiological and biochemical parameters (such as germination, photosynthesis, biomass, water status, and nutrient uptake) and yield. Overall, in this article, we have reviewed the role of different phytohormones, osmolytes, exogenous compounds, proteins, plant growth-promoting microbes (PGPM), omics approaches, and genome editing technologies like clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (CRISPR-Cas9) in alleviating drought effects in plants. We also proposed that developing drought-tolerant plant varieties requires the combined use of biotechnological and agronomic approaches and cutting-edge genome editing (GE) tools.
Asunto(s)
Sistemas CRISPR-Cas , Sequías , Edición Génica , Plantas , Estrés FisiológicoRESUMEN
Endophytic mycopopulation isolated from India's Queen of herbs Tulsi (Ocimum sanctum) were explored and investigated for their diversity and antiphytopathogenic activity against widespread plant pathogens Botrytis cinerea, Sclerotinia sclerotiorum, Rhizoctonia solani and Fusarium oxysporum. 90 fungal isolates, representing 17 genera were recovered from 313 disease-free and surface sterilised plant segments (leaf and stem tissues) from three different geographic locations (Delhi, Hyderabad and Mukteshwar) during distinct sampling times in consequent years 2010 and 2011 in India. Fungal endophytes were subjected to molecular identification based on rDNA ITS sequence analysis. Plant pathogens such as F. verticillioides, B. maydis, C. coarctatum, R. bataticola, Hypoxylon sp., Diaporthe phaseolorum, Alternaria tenuissima and A. alternata have occurred as endophyte only during second sampling (second sampling in 2011) in the present study. Bi-plot generated by principal component analysis suggested tissue specificity of certain fungal endophytes. Dendrogram revealed species abundance as a function of mean temperature of the location at the time of sampling. Shannon diversity in the first collection is highest in Hyderabad leaf tissues (H' = 1.907) whereas in second collection it was highest from leaf tissues of Delhi (H' = 1.846). Mukteshwar (altitude: 7500 feet) reported least isolation rate in second collection. Nearly 23% of the total fungal isolates were considered as potent biocontrol agent. Hexane extract of M. phaseolina recovered from Hyderabad in first collection demonstrated highest activity against S. sclerotiorum with IC50 value of 0.38 mg/ml. Additionally, its components 2H-pyran-2-one, 5,6-dihydro-6-pentyl and palmitic acid, methyl ester as reported by GC-MS Chromatogram upon evaluation for their antiphytopathogenic activity exhibited IC50 value of 1.002 and 0.662 against respectively S. sclerotiorum indicating their significant role in antiphytopathogenic activity of hexane extract. The production of 2H-pyran-2-one, 5,6-dihydro-6-pentyl from M. phaseolina, an endophytic fungus is being reported for the first time.
Asunto(s)
Ascomicetos , Botrytis , Fusarium , Ocimum/microbiología , Plantas Medicinales/microbiología , Rhizoctonia , Ascomicetos/clasificación , Ascomicetos/crecimiento & desarrollo , Ascomicetos/aislamiento & purificación , Biodiversidad , Botrytis/clasificación , Botrytis/crecimiento & desarrollo , Botrytis/aislamiento & purificación , Fusarium/clasificación , Fusarium/crecimiento & desarrollo , Fusarium/aislamiento & purificación , Enfermedades de las Plantas/microbiología , Rhizoctonia/clasificación , Rhizoctonia/crecimiento & desarrollo , Rhizoctonia/aislamiento & purificaciónRESUMEN
We report a 45-year-old male presenting with an intraoral mass originating from the right maxillary alveolar ridge. Radiologic investigations revealed osteolytic lesions in the right maxilla, skull, and lumbar vertebrae. This finding led to further investigations like electrophoresis of serum proteins for M band, quantitative estimation of immunoglobulins, urine electrophoresis for monoclonal light chain, and bone marrow biopsy. All these findings were inconclusive. Incision biopsy revealed the features of plasmacytoma. Since the other reports were incongruent with the histopathology report, for establishing a diagnosis of plasmacytoma, Immunohistochemistry of the specimen was done which revealed it to be a case of plasmablastic plasma cell neoplasm favoring plasmablastic lymphoma. The diagnostic confusion which arose in this setting is discussed in details.