Physiology and Molecular Biology of Plants最新文献

The extent of viral infection significantly shapes disease susceptibility. Yellow mosaic disease induced by the begomovirus pathogen mungbean yellow mosaic India virus (MYMIV), revealed varying infection levels in both compatible and incompatible interactions across three distinct Vigna species such black gram, green gram, and rice bean. Differential gene expression analysis focused on MYMIV coat protein (AV1) and replication protein (AC1) highlighted elevated AV1 expression in the susceptible green gram genotype SML1082 compared to the black gram genotype KUG253. Conversely, AC1 showed higher expression in black gram than green gram, illustrating complex infection mechanisms among compatible MYMIV-Vigna interactions. A novel infection pathway, termed "Lack of Efficient Assembly (LEA)," has been hypothesized in MYMIV-Vigna interactions. Additionally, a whitefly-mediated artificial transmission model for begomoviruses, named Transparent Airflow Stress-free Container (TASC), has been designed and demonstrated for the efficient transmission of MYMIV. This study enhances the understanding of begomovirus infection dynamics in diverse Vigna species, offering insights into disease management strategies.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-025-01547-9.

Global climate change poses a significant risk to agricultural productivity due to its diverse impacts on agricultural ecosystems, such as increased temperatures and altered precipitation patterns, all of which can adversely affect crop productivity. To overcome these challenges, plants have evolved intricate mechanisms to regulate stress responses and enhance stress tolerance. The SAL1 gene, which encodes a phosphatase enzyme, has emerged as a key player in plant stress responses. In this review, we provide an overview of the SAL1 gene, its functional significance, and its potential applications for improving stress tolerance in crops. To address the escalating global food demand amidst climate change challenges, it is imperative to pursue innovative strategies aimed at enhancing crop tolerance against abiotic stress.

MicroRNAs (miRNAs) are endogenous, small molecules that negatively regulate gene expression to control the normal development and stress response in plants. They mediate epigenetic changes and regulate gene expression at both transcriptional and post-transcriptional levels. Synthetic biology approaches have been utilized to design efficient artificial miRNAs (amiRNAs) or target-mimics to regulate specific gene expression for understanding the biological function of genes and crop improvement. The amiRNA based gene silencing is an effective technique to "turn off" gene expression, while miRNA target-mimics or decoys are used for efficiently down regulating miRNAs and "turn on" gene expression. In this context, the development of endogenous target-mimics (eTMs) and short tandem target mimics (STTMs) represent promising biotechnological tools for enhancing crop traits like stress tolerance and disease resistance. Through this review, we present the recent developments in understanding plant miRNA biogenesis, which is utilized for the efficient design and development of amiRNAs. This is important to incorporate the artificially synthesized miRNAs as internal components and utilizing miRNA biogenesis pathways for the programming of synthetic circuits to improve crop tolerance to various abiotic and biotic stress factors. The review also examines the recent developments in the use of miRNA target-mimics or decoys for efficiently down regulating miRNAs for trait improvement. A perspective analysis and challenges on the use of amiRNAs and STTM as potent tools to engineer useful traits in plants have also been presented.

India has a large potential for producing a variety of legumes which are proficiently valued for small grower to the highest producers. Plant viruses predominate among the many factors that affect the production of legumes. In tropical and subtropical locations, begomovirus has become a significant productivity barrier for legume production with significant losses. The detection and molecular characterization of various begomoviruses species have been done with regard to phylogenetic analyses, infectivity on host plants, DNA replication, transgenic resistance, promoter analysis, and development of virus-based gene-silencing vectors using several techniques. The molecular detection of begomoviruses involves a variety of techniques, including polymerase chain reaction (PCR), using degenerate primers, reverse transcription PCR (RT-PCR), real time quantitative PCR, rolling-circle amplification PCR (RCA-PCR assay), RCA, and microarray/DNA chip. Begomovirus infections can be prevented by various methods such as by controlling vector populations, use of culture practices, developing virus-free planting materials, developing resistant varieties, following quarantine regulations, and adapting modern methods, including pathogen-derived resistance (PDR), RNA interference (RNAi)-mediated resistance and genome editing approach. This review focuses on current status of geminiviruses infecting various legumes, pathogenesis, genetic flexibility, recombination of begomovirus responsible for the wide host range, modern methods of control, including PDR, RNAi-mediated resistance, small RNA (sRNA)- mediated resistance, Engineered Nucleases, Zinc Finger nucleases, Transcriptional Activator nucleases, CRISPR/Cas9 mediated genome editing and various strategies for management of begomoviruses. The present study entails the view and understanding of different approaches for the begomovirus management which state knowledge about limiting the crop losses.

Drought is a significant environmental issue affecting crop yield, nutrient content, and human food. This study investigates the potential of zinc oxide nanoparticles (ZnO-NPs) in mitigating the negative effects of drought stress on pea (Pisum sativum L.). ZnO-NPs were applied through seed priming, foliar application, and soil drenching at 0, 50, 100, and 150 ppm concentrations. Our findings showed that these three methods were more effective at different concentrations of ZnO-NPs. Seed priming at 50 ppm, foliar application at 100 ppm, and soil drenching at 150 ppm performed best in mitigating drought stress. Results showed that primed seeds with zinc oxide nanoparticles (50 ppm) have improved the physical growth, physiological, antioxidant, and mineral content by 35%, 45%, 57%, and 13% under drought stress as compared to control. It was observed that foliar application of ZnO-NPs (100 ppm) has enhanced physical growth, physiological, antioxidant, and mineral content by 43%, 54%, 64%, and 15% under drought stress as compared to the control. However, application of ZnO-NPs (150 ppm) in soli drenching improved the physical growth, physiological, antioxidant, and mineral content by 47%, 60%, 64%, and 16% under drought stress as compared to control. Moreover, ZnO-NPs amendments at different concentrations significantly decreased osmotic stress. This study provides innovative evidence of ZnO-NPs to mitigate drought stress in plants through various applications, revealing their potential to boost resilience in agriculture in case of drought stress conditions.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-024-01537-3.

Globally, tomato leaf curl disease (ToLCD) caused by begomoviruses and late blight disease caused by Phytophthora infestans are important limiting factors for tomato production. Development of disease resistant cultivars is an important objective of tomato breeding programmes. Resistance genes such as Ty2 and Ty3 against ToLCD, and Ph2 and Ph3 resistant genes against late blight were utilized in this study to develop tomato lines with ToLCD and late blight resistance. Two F₂ populations derived from the crosses viz., VRT4-20-18 × (LA3152 × LA4286) and LA3152 × VRT-78-2 were used as base material. Marker assisted selection was employed throughout the generation advancement programme to select plants with the targeted genes. Gene based molecular markers AW910upF2R3, Ty3-SCAR and Ph3SCAR were used to select genotypes containing the Ty2, Ty3 and Ph3 genes, respectively. The dTG-63/HinfI CAPS marker linked to Ph2 gene was used to select the Ph2 gene containing genotypes. Advanced lines with all the four genes and/ or in different combinations with desirable agronomic traits were developed. Further, these selected genotypes were also tested for resistance to both the diseases under natural epiphytotic and artificially inoculated conditions. Lines with the Ty-3 alone or in combination with the Ty-2 performed well against ToLCD with DSI < 1, whereas lines with both the Ph2 and Ph3 genes performed well against late blight with DSI < 1. Developed advanced lines in the study can play a greater role in stabilizing tomato production by minimizing the losses caused by these diseases.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-025-01548-8.

Peanut mottle virus (PeMoV) is a single-stranded RNA virus transmitted through seeds and aphids that affects peanut crops worldwide. Currently, Enzyme Linked Immune-Sorbent assays and Reverse-Transcription Polymerase Chain Reaction techniques are widely employed to detect PeMoV in infected plants. ELISA is labor-intensive and time-consuming, as it involves the preparation of buffers and the production of polyclonal antibodies. Even though RT-PCR bypasses the need for buffer preparation and antibody production, it demands trained professional's manpower, requires expensive equipment like thermal cyclers, and involves complex procedures such as RNA isolation and cDNA conversion. To avoid these constraints, there is a need for a fast, reliable, efficient, and economical method for detecting PeMoV to ensure the production of healthy seeds. This study optimized the Reverse Transcriptase Recombinase Polymerase Amplification (RT-RPA) method by eliminating the steps of RNA extraction, cDNA conversion, and the use of a thermal cycler. The optimized RT-RPA assay successfully detected PeMoV at concentrations as low as 10^-6 and 10^-7 dilutions (1 and 0.1 µg/µl) of both RNA an-6d crude sap templates, demonstrating high sensitivity comparable to the routine RT-PCR assay. The new RT-RPA technique was tested against other viruses that infect peanuts like the Peanut stunt Virus, Tomato spotted wilt virus and Peanut bud necrosis virus, this technique demonstrated great specificity and no cross-reactivity. The developed RT-RPA using a crude leaf sap template is time-saving, less laborious, not very complicated, high specificity, sensitivity, economical and efficient. Therefore, laboratories with limited resources can use the RT-RPA assay for preliminary screening of PeMoV in nurseries, farm and glasshouse conditions, and quarantine stations. The current study reports the development, optimization and validation of Reverse Transcriptase Recombinase Polymerase Amplification (RT-RPA) using crude sap as template for the onsite detection of PeMoV infection in peanut crops under field conditions for the first time.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-024-01545-3.

A roving field survey conducted during the year 2023, assessed the viral disease incidence of about 97% on pumpkin in a farmer holding at Coimbatore (Tamil Nadu, India). The diseased plants expressed symptoms such as severe mosaic, leaf malformation, upward cupping of terminal leaf, yellowing, and stunting. The disease was successfully transmitted by the whiteflies (Bemisia tabaci) to healthy pumpkin, with 24 h of acquisition access period and 12 h of inoculation access period. The samples were found to be associated with bipartite begomoviral DNA-A component of squash leaf curl Philippines virus (SLCPHV) along with DNA-B component of squash leaf curl China virus (SLCCNV) based on rolling circle amplification and DNA sequencing. The nucleotide sequence of DNA-A of SLCPHV (OR860425) shared the highest nucleotide identity of 94.5% with the previously reported SLCPHV isolate of Philippines. The DNA-B component of SLCCNV (OR860426) showed 94.9% identity with the Indian pumpkin isolate. The phylogenetic analysis explicated that the SLCPHV and SLCCNV isolates from pumpkin had common ancestry with SLCPHV and SLCCNV isolates from Philippines and India, respectively. Further analysis predicted intraspecies recombination events on their genome. This study confirms the association of non-cognate SLCPHV (DNA-A) with SLCCNV (DNA-B) causing mosaic disease on pumpkin and to the best of our knowledge it constitutes the first report of SLCPHV occurrence in India.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-024-01542-6.

Salinity stress poses a significant threat to sunflower (Helianthus annuus L.) by impairing water and nutrient uptake, disrupting cellular functions, and increasing oxidative damage. This study investigates the impact of Salicylic acid (SA) and silver nanoparticles (AgNPs) on growth, biochemical parameters, and oxidative stress markers in salt-stressed sunflower plants. Experiments were conducted in a controlled greenhouse environment at the Islamia University of Bahawalpur, Pakistan, using sunflower seeds (Orisun 701). AgNPs were synthesized using neem leaf extract and characterized through SEM, FTIR, zeta potential analysis, and XRD. Treatments included foliar application of SA (10 mM) and AgNPs (40 ppm) under 100 mM sodium chloride-induced salt stress. Growth metrics, antioxidant enzyme activities, chlorophyll content, and oxidative stress markers (H₂O₂ and MDA levels) were measured to evaluate treatment effects. The SA and AgNP treatments improved sunflower growth under salt stress, with AgNPs showing a greater impact. SA increased shoot fresh weight by 16.4%, root fresh weight by 6.9%, and chlorophyll content by 12.7%, while AgNPs enhanced shoot fresh weight by 30.5%, root fresh weight by 11.6%, and total chlorophyll by 80%. AgNPs also significantly reduced H₂O₂ by 42.7% and MDA by 34.6%, indicating reduced oxidative damage. Cluster analysis further demonstrated the distinct physiological responses elicited by AgNPs compared to SA. SA and AgNPs enhance sunflower resilience to salinity, with AgNPs showing a particularly strong effect on chlorophyll content and oxidative stress markers. These findings highlight the potential of SA and AgNPs as effective treatments for salt stress, suggesting further research across different crops and environments.

Plant viruses encode RNA silencing suppressor (RSS) proteins to counter the induced antiviral defense, an RNAi silencing mechanism of the host. Indian citrus ringspot virus (ICRSV) causes the ringspot disease, which leads to significant yield loss of kinnow orange. The ICRSV genome contains six open reading frames (ORFs), however, the ORF encoding the potential RSS is not yet known. In this study, we have attempted to identify the RSS protein of ICRSV. To this end, ORF 2,3,4,5 and 6 were cloned into pCAMBIA1302 (35s-GFP) vector, followed by transformation of Agrobacterium tumefaciens and agro-infiltration into leaves of Nicotiana benthamiana 16c line. Only the leaves infiltrated with 35s-GFP/ORF5 showed a GFP fluorescence signal similar to 35s-GFP/P19, a well-studied positive RSS. Usually, the induced host RNAi silencing is supposed to cleave the expressed GFP-RNA. However, it is suspected that ORF5-encoded protein was able to suppress the host silencing mechanism, leading to the retention of the GFP fluorescence signal. This finding was further supported by beta-glucuronidase (GUS) histochemical assays by infiltrating the construct expressing ORF5-GUS under 35s promoter in the leaves of N. benthamiana. Leaves infiltrated with 35s-GUS/ORF5 formed diX-indigo precipitate similar to leaves infiltrated with, indicating the RSS activity of ICRSV. Later, semi-quantitative PCR and quantitative reverse transcription PCR (qRT-PCR) assays showed a higher expression of GFP and GUS in ORF5 agro-infiltrated leaves. Together, these results suggest that ORF5 encoded protein has the potential RSS function of ICRSV which successfully suppresses host RNAi silencing mechanism.