Science, Volume 382, Issue 6666, Page 19-20, October 2023.
Award honors pair for mRNA work key to COVID-19 vaccines
Science, Volume 382, Issue 6666, Page 22-22, October 2023.
Family ties
Science, Volume 382, Issue 6666, Page 24-27, October 2023.
Physiological, transcriptional and metabolomic evidence for arbuscular mycorrhizal fungi and Lactobacillus plantarum in peanut resistance to salinity stress
Abstract
Arbuscular mycorrhizal fungi (AMF) and Lactobacillus plantarum (LP) play pivotal roles in plant salinity resistance; however, difficulties are still exist in ascertaining their synergistic effects in counteracting legume soil salinity. Here, two peanut cultivars (salt-tolerant and salt-sensitive) were subjected to salinity stress, and the alleviation effects of combined microbial agent (CMA, inoculation with AMF + application with LP) on peanut salinity tolerance have been comprehensively characterized. CMA significantly enhanced the biomass production, leaf relative water content, increased the net photosynthetic rate, the maximal photochemical efficiency of photosystem II (PSII) and strengthened the antioxidant system, while dramatically decreased the reactive oxygen species (ROS) accumulation, lipid peroxidation and relative electrolyte conductivity under salinity conditions. Moreover, transcriptional and metabolomic evidence advocated that a subset of stress-responsive pathways involved in plant growth (e.g. sucrose and starch), photosystem, antioxidant response, signal transduction (e.g. phytohormone and MAPK), osmotic homeostasis (e.g. total soluble sugar and amino acids) and root metabolism (e.g. asparagine and phenylpropanoid) have been regulated by CMA. Taken together, the physiological, transcriptional and metabolomic results indicate that CMA could induce peanut salinity tolerance through increasing plant growth performance, maintaining photosynthetic apparatus integrity, enhancing antioxidant system and regulating root metabolism. This study provides a promising CMA product and would be important for deepening the knowledge of the mechanisms regarding bacterial–fungal interactions.
Rapid and visual detection of grapevine fleck virus using recombinase polymerase amplification combined with lateral flow strips
Abstract
Grapevine flack virus (GFkV) causes fleck disease and leads to severe symptoms when the infection occurs with multiple viruses. Restricting the propagation of GFkV-infected grapevines is the ideal management strategy to control the spread of this virus. Therefore, the development of rapid detection methods for GFkV is urgently required. In the present study, we developed a rapid and reliable assay based on the reverse transcription-recombinase polymerase amplification (RT-RPA) combined with lateral flow strips (LFS) using sequence-specific primers and a probe-based coat protein sequences for the GFkV detection in grapevines. The GFkV RT-RPA-LFS assay was optimized at 38°C for 10 min and an extra 5 min LFS incubation time. The optimized RT-RPA-LFS assay had similar sensitivity to RT-PCR and showed no cross-reaction with major viruses infecting grapevines in Korea. The assay was successfully validated for GFkV detection in grapevine field samples. This study provides a reliable technique for rapidly detecting GFkV as an alternative diagnostic approach for producing virus-free grapevine nurseries.
Effects of water stress on endogenous hormones and free polyamines in different tissues of grapevines (Vitis vinifera L. cv. ‘Merlot’)
Zhennan Zhan, Ning Wang, Zumin Chen, Yanxia Zhang, Kangqi Geng, Dongmei Li, Zhenping Wang
Characterization of resistance to angular leaf spot of common bean (Phaseolus vulgaris L.) breeding line SPS50HB
Abstract
The common bean (Phaseolus vulgaris L.) makes an important contribution to the human diet, particularly in Africa and Latin America. Because angular leaf spot (ALS), caused by the fungal pathogen Pseudocercospora griseola, is one of the most severe foliar diseases of the bean plant, an important priority is to identify genes encoding resistance. The present study focused on the resistance shown by the Mesoamerican common bean breeding line SPS50HB. From the pattern of segregation for resistance displayed in an F2 population bred from a cross between SPS50HB and the ALS-susceptible Ethiopian variety Red Wolaita, it was concluded that the resistance of SPS50HB is controlled by two unlinked dominant genes. An allelism test indicated that one of these genes was either identical with, allelic to, or closely linked to the major gene Phg-2 carried by variety Mexico 54. The sequence-characterized amplified region assays OPEO4 and PF13, which are diagnostic for an ALS resistance gene carried by the germplasm accession G10909, both tracked a possible second gene present in SPS50HB.
Genetic analysis and identification of SSR marker linked to Phomopsis blight resistance in eggplant (Solanum melongena L.)
Abstract
The present investigation was carried out to decipher inheritance of resistance and to identify linked SSR markers for Phomopsis blight resistance in eggplant. An F2 population comprising 161 plants was developed from the cross of Pusa Kranti and BR-40-7. Genetic analysis was carried out using Chi square test. Artificial inoculation of fruits was carried out using pin prick method, and scoring was done as per the standard scoring scale. The F2 plants segregated into 92 susceptible (77—highly susceptible, 15—susceptible): 69 resistant (17—highly resistant, 27—resistant, 25—moderately resistant) suggesting complimentary epistasis with ratio of 9:7. To identify the putatively linked markers to resistance gene, parental polymorphic markers were subjected to bulk segregant analysis (BSA), and two markers (emk03O04 and emf11A03) could differentiate resistant and susceptible bulk and co-segregated with resistance gene. The genetic distance between the identified markers was found to be 18.12 cM using QTL IciMapping V3.2 software depicting two new QTLs on chromosome number 6. The identified QTLs have great significant importance in marker assisted breeding programme.
Genomic selection and enablers for agronomic traits in maize (Zea mays): A review
Abstract
Maize is a commodity crop providing millions of people with food, feed, industrial raw material and economic opportunities. However, maize yields in Africa are relatively stagnant and low, at a mean of 1.7 t ha−1 compared with the global average of 6 t ha−1. The yield gap can be narrowed with accelerated and precision breeding strategies that are required to develop and deploy high-yielding and climate-resilient maize varieties. Genomic and phenotypic selections are complementary methods that offer opportunities for the speedy choice of contrasting parents and derived progenies for hybrid breeding and commercialization. Genomic selection (GS) will shorten the crop breeding cycle by identifying and tracking desirable genotypes and aid the timeous commercialization of market-preferred varieties. The technology, however, has not yet been fully embraced by most public and private breeding programmes, notably in Africa. This review aims to present the importance, current status, challenges and opportunities of GS to accelerate genetic gains for economic traits to speed up the breeding of high-yielding maize varieties. The first section summarizes genomic selection and the contemporary phenotypic selection and phenotyping platforms as a foundation for GS and trait integration in maize. This is followed by highlights on the reported genetic gains and progress through phenotypic selection and GS for grain yield and yield components. Training population development, genetic design and statistical models used in GS in maize breeding are discussed. Lastly, the review summarizes the challenges of GS, including prediction accuracy, and integrates GS with speed breeding, doubled haploid breeding and genome editing technologies to increase breeding efficiency and accelerate cultivar release. The paper will guide breeders in selection and trait introgression using GS to develop cultivars preferred by the marketplace.
Identification of potential sources of mungbean yellow mosaic India virus resistance in black gram (Vigna mungo) and expression of antioxidants and R‐genes modulating resistance response in cultivated and its two wild relatives
Abstract
Black gram is one of the most important short duration grain legume, which contributes significantly towards nutritional security and environmental sustainability. The virus specific primers confirms the presence of mungbean yellow mosaic India virus (MYMIV) in representative samples. A total of 27 cultivated and two wild species were found as highly resistant (HR) to MYMIV and validated through molecular markers. The start codon target (SCoT) markers analysis revealed that the SCoT loci, namely, SCoT-4 (2200 bp), SCot-9 (1150/ 1200 bp), SCoT-15 (1150/1100 bp), SCoT-16 (700 bp), SCoT-24 (2500 bp), SCoT-25 (700 bp), SCoT-33 (900/1000 bp), and SCoT-34 (600 bp), were found unique, able to distinguish HR and highly susceptible (HS) genotypes. Biochemical characterization and gene expression profiling revealed the higher expression of antioxidants and R-genes just after pathogen inoculation indicated the activation of defence mechanism in both cultivated and its wild relatives, which modulates the resistant responses in cultivated and wild accessions. These information will be really helpful in accelerating resistance breeding in black gram.