Evaluation of Tomato Hybrids for Resistance against Tomato Mosaic Virus (ToMV)

Tomato mosaic virus (ToMV) drastically affects the tomato production worldwide. To deal with this problem, breeding of ToMV-resistant hybrids/varieties is the ultimate need and most successful approach. In wild tomato species, three dominant ToMV-resistant genes (Tm-1, Tm-2 and Tm-22 ) were identified and the World Vegetable Center developed few fresh market tomato lines resistant to ToMV by the introgression of these genes. Recently at Nuclear Institute for Agriculture and Biology, Faisalabad, Pakistan a breeding programme was initiated to develop high yielding and ToMV tolerant hybrids using these lines. Current study was performed to screen elite F1 hybrids carrying Tm gene along with their parents against ToMV using mechanical inoculation, confirmation of the virus using DAS-ELISA and marker assisted selection of hybrids. Out of 28 hybrids and 17 parent accessions/genotypes, eight hybrids and five accessions were found to be highly resistant and the virus was not detected in DAS-ELISA. Five hybrids were resistant, nine hybrids and four genotypes were tolerant, while the remaining six hybrids and eight genotypes were susceptible. For the confirmation of Tm-22 gene, the tomato hybrids and their parents were subjected to molecular analysis using cleaved amplified polymorphic sequence (CAPS) primers. The result of CAPS markers for the confirmation of Tm-22 gene was found consistent with phenotypic data of the inoculated tomato genotypes/ hybrids. Higher phenolic content, total soluble proteins, better CAT and SOD activities were positively correlated with resistance. Screening results based on phenotype, biochemical and molecular marker data indicate that hybrids carrying Tm-22 gene are good sources of resistance against ToMV

Biochemical Alterations in the Leaves of Resistant and Susceptible Mungbean Genotypes Infected withMungbean Yellow Mosaic India Virus

Mungbean (Vigna radiata), an important leguminous crop, is highly susceptible to yellow mosaic disease (YMD) caused by Mungbean yellow mosaic India virus (MYMIV), resulting in high yield penalty. Previously, different varieties of mungbean have been reported possessing resistance%252F tolerance against MYMIV. However, the molecular events occurring during compatible and incompatible interactions between mungbean and MYMIV are yet to be explored. Therefore, in this study using MYMIV-resistant (NM-2016), moderately resistant (NM-2011) and susceptible genotype (VC-1647C), alterations in various biochemical attributes due to MYMIV infection were analysed and compared with healthy non-inoculated control plants for understanding the resistance mechanism. After MYMIV inoculation, the level of total phenolic contents (TPC) and total soluble proteins (TSP) increased significantly in the susceptible genotype. However, the level of Malondialdehyde (MDA) and Ascorbate peroxidase (APX) remained same in all the genotypes. Level of superoxide dismutase (SOD) and catalase (CAT) decreased in the susceptible genotype but CAT level increased in the moderately resistant genotype. Protease level decreased significantly in all the genotypes while esterase level increased in moderately resistant and susceptible genotype. Peroxidase (POD) increased only in moderately resistant genotype and Total Oxidant Status (TOS) increased significantly in the susceptible genotype. Due to MYMIV infection the level of all plant pigments decreased in all the genotypes tested. The comparative proteome analysis using SDS-PAGE resolved 22 peptides with molecular weight from 12.5 to 163 kDa. Differential expression of protein phosphatase 2C (PP2C) and Cytochrome b6 (Photosynthesis) in resistant and moderately resistant genotypes%253B Pectin acetyl esterase and Resistant specific protein-1(4) in resistant genotype and up-regulation of superoxide dismutase [Cu-Zn] and RuBisco by MYMIV may have triggered signal transduction pathway and consequently induced a resistance response against MYMIV in V. radiata by activating PR proteins

Comparison of solvent evaporation and ultrasonicassisted production methods in the development of nimesulide nanosponges and their characterization

Purpose: To compare solvent evaporation and ultrasonic assisted synthesis in preparation of nimesulide nanosponges using polyvinyl-alcohol and Eudragit L100 as a polymer/copolymer and dichloromethane as a cross linker.Methods: Twelve formulations of nimesulide were prepared, six with each method by varying the ratios of both polymer and co-polymer. The resulting nanosponges were evaluated characterized by preformulation studies, production yield (%), differential scanning calorimeter, x-ray diffraction, Fourier transformation infrared spectroscopy, scanning electron microscopy, entrapment efficiency (%), actual drug content (%) and in-vitro dissolution studies.Results: The results revealed that the formulation with high amounts of co-polymer in both methods showed crystalline structures with enhanced dissolution rates in basic media. Drug entrapment was higher for products prepared by solvent evaporation method (74 %) than that prepared by ultrasonic assisted method (61 %). This correlates with the enhanced dissolution rates for products by solvent evaporation method and increased solubility due to drug-polymer complex formation.Conclusion: Formulations made by solvent evaporation method demonstrate higher production yield and drug entrapment. However, both methods exhibit enhanced dissolution rates in basic medium generally as well as other characteristics that are comparable to nanosponges reported in the literature with regard to their comb like structure

A comprehensive review on Gossypium hirsutum resistance against cotton leaf curl virus

Cotton (Gossypium hirsutum L.) is a significant fiber crop. Being a major contributor to the textile industry requires continuous care and attention. Cotton is subjected to various biotic and abiotic constraints. Among these, biotic factors including cotton leaf curl virus (CLCuV) are dominant. CLCuV is a notorious disease of cotton and is acquired, carried, and transmitted by the whitefly (Bemisia tabaci). A cotton plant affected with CLCuV may show a wide range of symptoms such as yellowing of leaves, thickening of veins, upward or downward curling, formation of enations, and stunted growth. Though there are many efforts to protect the crop from CLCuV, long-term results are not yet obtained as CLCuV strains are capable of mutating and overcoming plant resistance. However, systemic-induced resistance using a gene-based approach remained effective until new virulent strains of CLCuV (like Cotton Leaf Curl Burewala Virus and others) came into existence. Disease control by biological means and the development of CLCuV-resistant cotton varieties are in progress. In this review, we first discussed in detail the evolution of cotton and CLCuV strains, the transmission mechanism of CLCuV, the genetic architecture of CLCuV vectors, and the use of pathogen and nonpathogen-based approaches to control CLCuD. Next, we delineate the uses of cutting-edge technologies like genome editing (with a special focus on CRISPR-Cas), next-generation technologies, and their application in cotton genomics and speed breeding to develop CLCuD resistant cotton germplasm in a short time. Finally, we delve into the current obstacles related to cotton genome editing and explore forthcoming pathways for enhancing precision in genome editing through the utilization of advanced genome editing technologies. These endeavors aim to enhance cotton’s resilience against CLCuD

Evaluation of Bt-cotton Genotypes for Resistance to Cotton Leaf Curl Disease under High Inoculum Pressure in the Field and Using Graft Inoculation in Glasshouse

Bt-cotton germplasm, consisting of 75 genotypes was evaluated against cotton leaf curl disease (CLCuD) under high inoculum pressure in the field and using graft inoculation in glasshouse by visual symptom scoring assessments. None of the tested genotype was found disease free under both evaluation tests. Under field conditions in 2011, 3 genotypes were found resistant, 4 moderately resistant, 3 tolerant, 2 moderately susceptible and one susceptible; in 2012, 3 genotypes were tolerant, 7 moderately susceptible, 5 susceptible and 38 highly susceptible; in 2013, one was moderately susceptible and 51 were highly susceptible with varying degree of percent disease index (PDI) and severity index (SI). However, through graft evaluation in glasshouse, none of the graft inoculated plant was symptomless. All tested genotypes showed disease symptoms with SI values ranging between 5.0 and 6.0, and latent period between 12 and 14 days. Of the 75 genotypes evaluated using graft inoculation, 11 were found susceptible with SI values of 5.0 to 5.4 while remaining 64 were highly susceptible with SI values of 5.5 to 6.0. Inoculated plants of all tested genotypes exhibited severe disease symptoms within 10 days after the appearance of initial symptoms. No reduction in SI value was observed until the end of the experiment i.e., 90 days after grafting. Information generated under the present study clearly demonstrates that no sources of resistance to CLCuD are available among the tested Bt-cotton genotypes. So, a breeding programme is needed to introgress the CLCuD-resistance from other resistant sources to agronomically suitable Bt-cotton genotypes

Diversity in Betasatellites Associated with Cotton Leaf Curl Disease During Source-To-Sink Movement Through a Resistant Host

Cotton leaf curl is devastating disease of cotton characterized by leaf curling, vein darkening and enations. The disease symptoms are induced by DNA satellite known as Cotton leaf curl Multan betasatellite (CLCuMuB), dominant betasatellite in cotton but another betasatellite known as Chili leaf curl betasatellite (ChLCB) is also found associated with the disease. Grafting experiment was performed to determine if host plant resistance is determinant of dominant population of betasatellite in cotton (several distinct strains of CLCuMuB are associated with the disease). Infected scion of Gossypium hirsutum collected from field (the source) was grafted on G. arboreum, a diploid cotton species, resistant to the disease. A healthy scion of G. hirsutum (sink) was grafted at the top of G. arboreum to determine the movement of virus/betasatellite to upper susceptible scion of G. hirsutum. Symptoms of disease appeared in the upper scion and presence of virus/betasatellite in the upper scion was confirmed via molecular techniques, showing that virus/betasatellite was able to move to upper scion through resistant G. arboreum. However, no symptoms appeared on G. arboreum. Betasatelites were cloned and sequenced from lower scion, upper scion and G. arboreum which show that the lower scion contained both CLCuMuB and ChLCB, however only ChLCB was found in G. arboreum. The upper scion contained CLCuMuB with a deletion of 78 nucleotides (nt) in the non-coding region between A-rich sequence and βC1 gene and insertion of 27 nt in the middle of βC1 ORF. This study may help in investigating molecular basis of resistance in G. arboreum

Transcriptomics reveals multiple resistance mechanisms against cotton leaf curl disease in a naturally immune cotton species, Gossypium arboreum.

Cotton leaf curl disease (CLCuD), caused by cotton leaf curl viruses (CLCuVs), is among the most devastating diseases in cotton. While the widely cultivated cotton species Gossypium hirsutum is generally susceptible, the diploid species G. arboreum is a natural source for resistance against CLCuD. However, the influence of CLCuD on the G. arboreum transcriptome and the interaction of CLCuD with G. arboreum remains to be elucidated. Here we have used an RNA-Seq based study to analyze differential gene expression in G. arboreum under CLCuD infestation. G. arboreum plants were infested by graft inoculation using a CLCuD infected scion of G. hirsutum. CLCuD infested asymptomatic and symptomatic plants were analyzed with RNA-seq using an Illumina HiSeq. 2500. Data analysis revealed 1062 differentially expressed genes (DEGs) in G. arboreum. We selected 17 genes for qPCR to validate RNA-Seq data. We identified several genes involved in disease resistance and pathogen defense. Furthermore, a weighted gene co-expression network was constructed from the RNA-Seq dataset that indicated 50 hub genes, most of which are involved in transport processes and might have a role in the defense response of G. arboreum against CLCuD. This fundamental study will improve the understanding of virus-host interaction and identification of important genes involved in G. arboreum tolerance against CLCuD