Physiology and Molecular Biology of Plants最新文献

This study explores the utilization of plant-based systems for the production of monoclonal antibodies (MAbs), specifically targeting the Papaya ringspot virus (PRSV). Traditionally, immunodiagnostics for PRSV rely on labor-intensive methods involving animal-based production of polyclonal antibodies (PAbs). In contrast, this research demonstrates the feasibility of expressing PRSV V_L antibody fragments in Nicotiana benthamiana plants, leveraging their ability to perform eukaryotic protein synthesis and glycosylation. Plant-based platforms offer advantages such as flexibility, scalability, lower production costs, and reduced risk of contamination by animal pathogens. While plantibodies have historically been used for plant immunization and pathogen resistance, this study pioneers their application in pathogen detection within host plants. Such advancements could significantly streamline and democratize disease detection, potentially mitigating crop losses and enhancing agricultural sustainability.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-025-01563-9.

Plant viruses adversely affect worldwide agriculture and cause immense crop yield losses globally. Scientists have developed various strategies to combat the viral attacks on plants and one such ground-breaking discovery is the RNA interference (RNAi), also known as RNA silencing. RNA silencing has evolved as a major tool for developing viral resistance in plants through gene silencing that involves the intricate use of various small RNAs, such as small interfering RNAs (siRNAs), endogenous microRNAs (miRNAs), artificial miRNAs (amiRNAs), hairpin RNAs (hpRNAs), double-stranded (ds) RNA sprays (topical applications), and the less prevalent short hairpin (sh) RNAs. With tailor-made constructs, RNAi has opened the avenues for the immense potential to down-regulate the desired viral target genes, leading to reduced viral pathogenicity in several crop plants leading to enhanced sustainability in agriculture and food security for the teeming millions across the globe. In this article, we have reviewed the advances made in the generation of virus-resistant plants by using RNAi-based approaches, particularly siRNA- and amiRNA-mediated technologies. Despite certain issues with delivery, specificity, resistance, and safety that impede the RNAi-based treatments, targeted RNA silencing is expected to revolutionize the future agricultural research with tailor-made stress-tolerant crop plants.

Banana bunchy top virus (BBTV) is a major threat to banana and plantain cultivation in several tropical and sub-tropical regions of the world including India, causing significant yield losses. Despite removal of symptomatic bunchy top infected plants and chemical control of aphids in the field, the disease is not completely eliminated. To investigate the latency phenomenon associated with banana bunchy top disease, experiments were conducted. In the transmission assay for BBTV in cv. Grand Nain (AAA) with the viruliferous banana black aphid (Pentalonia nigronervosa), 56.56% of plants expressed typical symptoms within 35 days after inoculation (DAI) whereas 29.1% showed symptoms between 36 and 70 DAI. Interestingly, 1.64% of plants remain asymptomatic upto 257.93 days. Upon quantification of viral titre during the latent period through SYBR green-based qPCR assay, virus copy number was found to be negatively correlated with latency duration. Furthermore, plants with a disease scale of 5 showed a maximum transmission rate of 60%, whereas asymptomatic banana plants (cv. Grand Nain) still showed a transmission rate of 3-6%. These results show the existence of BBTV in a latent form in asymptomatic banana plants and emphasize the importance of creating awareness among the tissue culture industries and farmers about virus indexing and the use of virus-free planting materials. This study is the first of its kind to expatiate upon the latency exhibited by BBTV in banana.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-025-01610-5.

Whiteflies Bemisia tabaci (Hemiptera: Aleyrodidae) are well-known agricultural pests responsible for transmitting plant viruses and causing significant crop damage. B. tabaci is a complex of different cryptic species for which molecular techniques are crucial for discriminating between variants like the MEAM1 (formerly B) and MED (formerly Q) types of B. tabaci due to morphological inconsistencies. This study presents the development of a rapid, isothermal-based assay using recombinase polymerase amplification (RPA) to detect Whitefly MEAM1 and MED biotypes. By targeting mtcox1-specific genomic regions unique to each biotype, this assay provides a sensitive and efficient method for identifying these economically important whitefly variants in under 90 min, without the need for nucleic acid extraction and PCR machine; direct whitefly samples serve as templates and a small heat block is sufficient for assay performance. The study demonstrates successful primer validation, ensuring the specificity and sensitivity of the assay. Specifically designed primers accurately identified target mtcox1 regions unique to each type, enhancing the assay's precision. The RPA assay exhibited high specificity, detecting only the target variants without cross-reactivity to related species or non-target organisms. Additionally, the assay demonstrated exceptional sensitivity, capable of detecting ten-copy targets in Artificial Plasmid Control plasmid control and 100 pg whitefly nucleic acid. These results highlight the potential of RPA as a valuable tool for rapid and accurate detection of Whitefly MEAM1 and MED biotypes, aiding in the development of efficient pest control strategies in agriculture.

The Mitogen-Activated Protein Kinase (MAPK) cascade is an evolutionarily conserved signaling pathway that perceives various external and internal signals and governs an array of biological processes. Studies have shown MAPK's role in plant development and defense against diverse pathogens. However, MAPK's role in plant-virus interactions remains relatively unexplored, making it an active area of research. Recent studies have emphasized the role of MAPK in viral defense and the tri-trophic interactions of pant-insect-vector interactions. Although studies elucidating viral counter-defense are limited, some recent works have shown the direct interaction of viral proteins with MAPKs thwarting MAPK-mediated defense. Drawing insights from recent works, we have thoroughly examined the MAPK cascade in plant virus interactions, providing a concise yet comprehensive overview of this dynamic field.

Yellow mosaic disease (YMD), caused by the mungbean yellow mosaic India virus (MYMIV), represents a significant threat to soybean production in Southeast Asia, particularly in India. This study assessed 230 soybean breeding lines from the All India Coordinated Research Programme (AICRP) for YMD resistance through multi-year field trials conducted at IARI, New Delhi, a hotspot location conducive to natural epiphytotic conditions for YMD. Disease impact was evaluated using the coefficient of infection (CI), which combines both percent disease incidence and severity grades, as well as the Area Under the Disease Progress Curve (AUDPC). Fifty-seven resistant genotypes proceeded to the advanced varietal trials (AVT1 and AVT2). Statistical analyses, including BLUP, WAASB, and WAASBY indices, identified SL 958 (WAASBY = 22.54) as the most resistant and stable genotype. Other promising highly resistant genotypes included NRC-137, SL 1074, PS 1572, SL 1028, DS 3106 and HIMSO 1690 all of which demonstrated favourable agronomic traits such as high yield, optimal plant height, seed weight, and maturity. Molecular characterization of the virus from infected samples collected at the YMD hotspot in New Delhi and the emerging hotspot in Dharwad confirmed the presence of the mungbean yellow mosaic India virus (MYMIV). The DNA-B sequence from the Dharwad isolate revealed a unique breakpoint through recombination analysis, indicating genetic variation between the isolates from the two locations. Highly resistant soybean lines identified through field testing were further validated for their resistance under controlled conditions using whitefly-mediated transmission and agroinoculation. All seven highly resistant lines were ultimately selected, as they exhibited no visible symptoms or minute yellow flecks under artificial inoculation conditions. qPCR analysis of five highly resistant genotypes indicated low accumulation of virus in comparison to susceptible controls. These findings will assist decision-makers in releasing these advanced soybean breeding lines into seed production chains for cultivation by farmers.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-025-01614-1.

The members of the family, Geminiviridae, cause severe diseases in a wide range of economically important crops across continents. In the Indian sub-continent, chilli leaf curl disease (ChiLCD) caused by begomoviruses has emerged as a major constraint for chilli cultivation. Here, we report the identification of 16 begomoviruses and 6 betasatellites with ChiLCD from 16 locations covering 7 states in India. In the regions surveyed, chilli leaf curl virus and tomato leaf curl New Delhi virus were identified as the pre-dominantly distributed begomovirus species. Similarly, tomato leaf curl Bangladesh betasatellites and tomato leaf curl Joybebpur betsatellites were detected in the samples collected from 6 out of 16 locations. However, we have failed to detect any DNA-B component in these samples. Further, inter-species recombination has possibly contributed to the emergence of these cloned viral components. This study further emphasized the current status on the distribution of begomoviruses and betasatellites with ChiLCD in the major chilli-growing regions of India. This epidemiological data might help in devising efficient antiviral strategies to curb this disease.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-025-01570-w.

Every year rapid spreading of Begomovirus infection in plant causes a great economic loss in many countries of the world. To control the increasing rate of viral infectivity exclusive study on its transmission mechanism is required. This virus is transmitted through whitefly vector. Whitefly moves from one plant to another plant to suck phloem sap and spread virion particles. Transmission capability of virus may depend on the genetic variations within the cryptic species groups of whiteflies. Two distinct categories of begomoviruses viz., bipartite and monopartite were reported based on their different genome organization. According to ICTV, Old world begomoviruses may be monopartite or bipartite (distributed in Europe, Africa, Asia, and Oceania) whereas new world begomoviruses consist of mostly bipartite species (mainly found in America). Virion particles invade the preferable host plant (e.g. tomato, cotton etc.) and modify the intracellular ambience of plant according to their need to replicate and survive. Replication of virus mainly occurs through rolling circle replication and/or recombination driven replication methods. The most crucial factor for the establishment of infection, is the interaction among host, vector and pathogen. Several endosymbiotic organisms living within the vector also play significant role here. To stave off viral infection, host plant responds through several defensive activities like transcriptional gene silencing, post-transcriptional gene silencing, ubiquitination, autophagy, hormonal regulation, metabolic alteration etc. However, virus also counteracts remarkably through the manipulation of different pathways of cellular events of host plant. Thinking in the direction of the development of begomovirus resistance within host plants is necessary. Analytical study in different directions regarding the interaction between virus and plant and utilization of respective advanced molecular biological techniques may give cues to a new avenue.

Histones are rapidly loaded onto the geminivirus genome upon entry into plant cells leading to the formation of a eukaryotic chromatin-like structure "minichromosome" that supports its replication and transcription but the underlying mechanism behind this process has not been fully defined. From a host-virus perspective, histone chaperones, a crucial component in regulating chromatin architecture are recognized as a potential determinant in animal virus infection and are well studied, but their possible involvement in plant virus pathogenesis has been unexplored. ASF1, a pivotal histone chaperone facilitates the deposition of histone H3 and H4 onto DNA, which is necessary for the formation of eukaryotic chromatin. Here, we report that overexpression of specific histone chaperones (HCs) NbASF1A and NbASF1B genes facilitate the deposition of histone onto incoming virus DNA preventing its accessibility for both DNA synthesis and transcription machinery and this approach efficiently limits the development of geminivirus related disease symptoms progression. Conversely, the knockdown of both NbASF1A and NbASF1B enhances virus accumulation and disease progression and this process is supported by the Radiation sensitive protein 51 (RAD51) of Homologous recombination repair (HRR) pathway. This study presents a novel finding about HCs NbASF1A and NbASF1B conferring robust antiviral defence against geminiviruses.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-025-01580-8.