Publications of NIPGR Scientists

Permanent URI for this communityhttps://ndkr-library.nipgr.ac.in/handle/123456789/1

Browse

Author: search.filters.author.Pandey, PrachiSubject: search.filters.subject.Combined stress

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Drought attenuates plant responses to multiple rhizospheric pathogens: A study on a dry root rot-associated disease complex in chickpea fields
    (Elsevier B.V., 2023) Chilakala, Aswin Reddy; Pandey, Prachi; Durgadevi, Athimoolam; Kandpal, Manu; Patil, Basavanagouda S.; Rangappa, Krishnappa; Reddy, Puli Chandra Obul; Ramegowda, Venkategowda; Senthil-Kumar, Muthappa
    Context or problem: Root rots, a major factor contributing to yield loss in chickpea, often occur in disease complexes. Objective or research question: Plant responses to disease complexes are not well elucidated. We sought a clear understanding of a newly identified disease complex in chickpea, dry root rot (DRR)–wilt disease complex, in the field and studied the effect of drought on the severity of the complex and its effect on yield. We compared plant responses to DRR alone and the disease complex under drought and determined the phytohormones involved in plant defense against the disease complex. Methods: We compared the effect of 14 environments (two soil moisture regimes at seven locations) on the incidence of the disease complex and yield loss in four chickpea genotypes. We also studied the effect of drought on rhizospheric and root endo-microbial communities by whole-genome and metagenomic sequencing and performed LC-MS-based phytohormonal profiling of chickpea roots. Results: Soil moisture and plant genetic variability were critical in modulating disease incidence in field conditions. DRR was the primary driver of the disease complex under drought stress. Drought aggravated the yield reductions caused by the disease complex from 35% to 60% in susceptible genotypes. Further, drought-tolerant genotypes performed better under combined disease complex infection and drought stress and exhibited lesser yield losses than susceptible genotypes. Pathogenic fungi such as Macrophomina phaseolina, Fusarium oxysporum, and Rhizoctonia solani were enriched in the chickpea rhizosphere, and M. phaseolina was predominant in infected chickpea roots under both well-watered and drought conditions. Symbiotic associations of chickpea with nitrogen-fixing bacteria were suppressed under drought stress. Abscisic acid, jasmonic acid, and salicylic acid were found to be involved in defense against the disease complex across various stages of plant growth. Implications or significance: We highlight the interaction between drought and soil pathogens affecting chickpea yield and suggest the utilization of drought-tolerant root traits as donor traits for improving combined stress resistance. We also demonstrate growth stage–dependent phytohormonal responses elicited by DRR and the DRR–wilt disease complex. The identification and management of root rots is essential, and our findings offer valuable new insights into a lesser-known but highly significant disease complex of chickpea. Data availability statement: Manuscript data is available at Supplementary File S1. The soil microbe whole-genome and metagenome and root-microbe 16 S and ITS sequencing data are available at NCBI PRJNA871091 and PRJNA895851.
  • Thumbnail Image
    Item
    Plant responses to combined drought and pathogen infection: current understanding on the role of phytohormones
    (Springer, 2017) Pandey, Prachi; Senthil-Kumar, Muthappa
    Plants under natural conditions encounter a number of abiotic and biotic stresses often being inflicted simultaneously. Plant responses to a stress are governed by intricate network of the hormone signaling pathways. Abscisic acid (ABA) forms the major component of the plant response to drought and cold stress. Salicylic acid (SA), jasmonic acid (JA), and ethylene act as key regulators of plant response to pathogen infection. In fact, the extensive cross talk among the different hormone-mediated signaling pathways determines plant response to a particular stress. A large number of studies focus on hormone signaling under individual drought and pathogen stresses and the cross talk between the two stress responses. However, owing to the relatively few studies on combined drought and pathogen stresses, our understanding of phytohormonal signaling under combined stress is still obscure. Recent studies on combined drought and pathogen infection indicate that plants when simultaneously exposed to the two stresses often exhibit a transcriptional and metabolic response different from that exhibited under single stress conditions. This is also applicable to the phytohormonal signaling. The nature, time, and severity of the two stresses in combination modulate hormonal concentrations as well as the hormone signal transduction pathways involved. In this chapter, we provide a compendious description of the role of the three major hormones, namely, ABA, SA, and JA, in combined drought and pathogen infection. A brief description of the role of auxins, cytokinins, and gibberellins has also been provided. Taking leads from few studies, we have discussed the potential role of hormones in conferring combined drought and pathogen stress tolerance to plants. We also briefly discussed the effect of different “stress elicitors” on hormone signaling.
  • Thumbnail Image
    Item
    Tailored responses to simultaneous drought stress and pathogen infection in plants
    (Springer, 2016) Choudhary, Aanchal; Pandey, Prachi; Senthil-Kumar, Muthappa
    Under field conditions plants are often challenged by combination of biotic and abiotic stressors and they severely affect crop productivity. An increasing number of studies suggest that plants “tailor” their adaptation strategies to combat simultaneously occurring stresses. The stress combat strategies of plants are customized according to the stress combination and vary with the intensity and timing of the stresses involved. While some of the responses seen under combined stress are commonly instigated by individual stresses, some other are uniquely triggered under combined stress. Since some responses are unique only to the combined stress, the outcome of a stress interaction cannot be completely predicted using results from individual stress studies. In this chapter, the effects of combinatorial drought stress and pathogen infection on plants are discussed with an emphasis on the molecular and physiological mechanisms that underpin how plants tolerate simultaneously occurring stresses. We also highlight the complexity involved in the responses of plants to multiple stresses and underscore the importance of studying plant stressors in combination.