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Cucurbita crops, which include market types of pumpkin and squash, have unparalleled fruit variation and equally important economic value worldwide. Pumpkin and squash have versatile uses but are most popular in culinary, ornamental, snacking, and seed oil industries. The production of Cucurbita crops is hindered by diseases caused by fungal, oomycetes, and viral pathogens. Host resistance is an important component of integrated disease management for Cucurbita crops and is a major goal for plant breeders. This review addresses the major diseases of Cucurbita, including powdery mildew, downy mildew, Phytophthora rot, and aphid and whitefly transmitted viruses, with an emphasis on germplasm exploitation for the development of resistant cultivars. Resistance to powdery mildew derived from Cucurbita okeechobeensis subsp. martinezii (designated PM‐0) has been extensively deployed in commercial cultivars and was recently mapped on chromosomes 3 and 10 of Cucurbita moschata and Cucurbita pepo, respectively. Resistance to Phytophthora crown rot is present across several Cucurbita species, including Cucurbita lundelliana, C. okeechobeenesis subsp. okeechobeenesis, C. moschata, and C. pepo. Mapping studies have identified significant loci associated with Phytophthora crown rot resistance on chromosomes 4, 11, and 20 of C. moschata and chromosomes 4, 5, 8, 12, 13, 16, and 19 of C. pepo. Sources of resistance to aphid‐transmitted viruses exist in C. moschata, Cucurbita ficifolia, Cucurbita ecuadorensis, Cucurbita martinezii, C. ecuadorensis, Cucurbita maxima, and Cucurbita foetidissima. The availability of DNA markers linked to resistance against zucchini yellow mosaic virus and papaya ringspot virus in C. moschata and C. pepo has facilitated marker‐assisted selection (MAS) in breeding programs. On the other hand, sources of resistance to tomato leaf curl New Delhi virus (ToLCNDV), a major whitefly‐transmitted virus in Cucurbita, have been identified in C. moschata, C. lundelliana, and C. okeechobeensis. A major locus conferring resistance to ToLCNDV in C. moschata was recently mapped on chromosome 8 enabling the application of MAS with a prediction accuracy of 94.3%. Overall, the continued discovery and application of genomic tools for resistance breeding in Cucurbita will accelerate the rate of genetic gain while reducing costs associated with phenotyping. Core Ideas: Resistance to powdery mildew, designated PM‐0, has been extensively deployed in commercial cultivars.Resistance to Phytophthora crown rot is available in Cucurbita lundelliana, Cucurbita okeechobeenesis, Cucurbita moschata, and Cucurbita pepo.Sources of resistance to aphid‐transmitted viruses exist in at least seven Cucurbita species.Resistance to tomato leaf curl New Delhi virus is present in C. moschata, C. lundelliana, and C. okeechobeensis.Availability of genomic tools in Cucurbita will accelerate the rate of genetic gain for resistance breeding. Plain Language Summary: Pumpkin and squash are important crops worldwide. Some of the main plant diseases affecting cultivation of pumpkin and squash include mildews, viruses, and fruit and stem rots. Development of cultivars resistant to these diseases is important for growers as it helps cut the costs associated with production. Many sources of resistance to these diseases have been identified. DNA markers linked to genetic resistance will aide plant breeders in the process of selecting plants carrying suitable resistance genes. [ABSTRACT FROM AUTHOR]

Phytophthora capsici incites foliar blight, root, fruit, and crown rot in squash (Cucurbita spp.) and limits production worldwide. Resistance to crown rot in C. moschata breeding line #394-1-27-12 is conferred by three dominant genes, but the molecular mechanisms underlying this resistance are poorly understood. In the current study, RNA sequencing was used to investigate transcriptional changes in #394-1-27-12 (resistant) and Butterbush (susceptible) following infection by P. capsici at 12, 24, 48, 72, and 120 h post inoculation (hpi). Overall, the number of differentially expressed genes (DEGs) in Butterbush (2648) exceeded those in #394-1-27-12 (1729), but in both genotypes, the highest number of DEGs was observed at 72 hpi and least at 24 hpi. Our gene ontology (GO) analysis revealed a downregulation of the genes involved in polysaccharide and lignin metabolism in Butterbush but as an upregulation of those associated with regulation of peptidase activity. However, in #394-1-27-12, the downregulated genes were primarily associated with response to stimuli, whereas those upregulated were involved in oxidation–reduction and response to stress. The upregulated genes in #394-1-27-12 included defensin-like proteins, respiratory-burst oxidases, ethylene-responsive transcription factors, cytochrome P450 proteins, and peroxidases. These findings provide a framework for the functional validation of the molecular mechanisms underlying resistance to P. capsici in cucurbits. [ABSTRACT FROM AUTHOR]

The gram pod borer is a major pest of chickpea, accounting for average annual yield losses to the tune of 40–50%. VIP3Aa, a class of insecticidal protein with different receptor binding site in the insect's midgut compared to Bt-crystal protein, offers an alternative protection strategy against Lepidopteran insects. Here, we report evaluation of genetically engineered chickpea lines harboring codon modified Vip3Aa (cmVip3Aa) against the Lepidopteran insect pest, gram pod borer. The synthetic codon modified, cmVip3Aa gene of 2,370 bp was sub-cloned in modified plant expression vector and used for direct transformation of embryonic axis explants of chickpea (cv. DCP 92–3), with transformation efficiency of 4.30%. Presence and transmission of transgene across two generations were confirmed by PCR and Southern blot analyses in the five selected transgenic chickpea lines. Real Time PCR analyses indicated variable levels of cmVip3Aa expression in the transgenic chickpea lines (average Cq values 15.01±0.86 to 19.32±0.10), which were absent in the non-transgenic counterpart. Detached leaf insect bioassay indicate larval mortality (up to 39.75%), reduced larval feeding (up to 82.91%) and reduced larval weight gain (up to 68.23%), compared to control lines. Evaluation of gene offers a platform to identify efficacious insecticidal gene that can be used for insect resistance management in chickpea. [ABSTRACT FROM AUTHOR]

Rice is a global food grain crop for more than one-third of the human population and a source for food and nutritional security. Rice production is subjected to various stresses; blast disease caused by Magnaporthe oryzae is one of the major biotic stresses that has the potential to destroy total crop under severe conditions. In the present review, we discuss the importance of rice and blast disease in the present and future global context, genomics and molecular biology of blast pathogen and rice, and the molecular interplay between rice–M. oryzae interaction governed by different gene interaction models. We also elaborated in detail on M. oryzae effector and Avr genes, and the role of noncoding RNAs in disease development. Further, rice blast resistance QTLs; resistance (R) genes; and alleles identified, cloned, and characterized are discussed. We also discuss the utilization of QTLs and R genes for blast resistance through conventional breeding and transgenic approaches. Finally, we review the demonstrated examples and potential applications of the latest genome-editing tools in understanding and managing blast disease in rice. [ABSTRACT FROM AUTHOR]

Currently, India utilizes an enormous amount of fossil fuels and a major quantity of fossil fuels are imported from other countries. It's a giant load on the Indian Economy. The burning of fossil fuels causes global warming. Carbon neutral, renewable fuels are essential for environmental protection and it's economically sustainable for India. Biofuels attention day by day due to a rise in energy demands and environmental concerns. Biodiesel produced from algal oil a possible renewable and carbonneutral substitute to fossil fuels. The feasibility of the algal-based biodiesel industry depends on the selection of adequate species regarding commercial oil yields and oil quality. Present research work to bioprospecting and screening of 19 algal and blue-green algal species, the oil percentage and the fatty acid profiles, used for analyzing the biodiesel fuel properties. Oil from Tolypothrix phyllophila algal strain and compared it with another eighteen algal and blue-green algal strains from different literature. Tolypothrix phyllophila algal strain contains approximately 12.6% lipid on a dry weight basis. We also compared the FAME profile of 19 algal and blue-green algal strains and calculated and compared the fuel properties such as cetane number, Iodine Value, etc. of the biodiesel derived from these algal and blue-green algal oils based on chain length and saturation. We also investigated the 19 algal and blue-green algal fatty acid profiles and its suitability for biodiesel production and strains selection through PROMETHEE (Preference Ranking Organization Method for Enrichment Evaluations) and GAIA (geometrical analysis for interactive aid) analysis. [ABSTRACT FROM AUTHOR]

Biodiesel can substitute fossil fuels adequately and thus, considered 'future fuel'. Thus, identifying a promising algal strain for efficient biodiesel production is a very important endeavor. In the present investigation, the blue green algae, Anabaena constricta could be grown aseptically attaining exponential phase, 3 days post inoculation, responds to phototropism and amenable to both autotrophic and heterotrophic mode. Phylogenetic analysis reveal that Anabaena constricta grouped separately from other algal strains used in the study, making it unique in nature. Further, comparative studies of selected algal and blue green algal strains based on the oil percentage and fatty acid profile indicate potential biodiesel properties. The total lipid content of Anabaena constricta is estimated to 14% of the dry weight, and fatty acids profiling indicate presence of 11 fatty acid methyl esters (FAMEs), principally palmitic acid (16:0), oleic acids (18:1), linoleic acid (18:2), palmitoleic acid (16:1). The algal species, Hydrodictyon registered highest percentage of unsaturated fatty acids (59.5%), while highest content of saturated fatty acid was found in Anabaena constricta (51.5%). Cetane Number of seven algal and blue green algal biodiesel varied from 54.77 to 58.2 and Saponification Value varied from 205.6 to 211.39. PROMETHEE & GAIA analyses indicate both the Rhizoclonium and Tolypothrix species outranked while Hydrodictyon and Anabaena constricta are the least suitable species in seven algal and blue-green algal species studied for biodiesel production. Well-characterized strains offer promise for biodiesel production at a cost-effective level. The present study focus on the renewable fuel, which is useful for reducing the carbon footprint with potential to impact selfsustainability in fuel sector, without modification in current infrastructure. [ABSTRACT FROM AUTHOR]

Domain swapping and generation of chimeric insecticidal crystal protein is an emerging area of insect pest management. The lepidopteran insect pest, gram pod borer (Helicoverpa armigera H.) wreaks havoc to chickpea crop affecting production. Lepidopteran insects were reported to be controlled by Bt (cryI) genes. We designed a plant codon optimized chimeric Bt gene (cry1Aabc) using three domains from three different cry1A genes (domains I, II, and III from cry1Aa, cry1Ab, and cry1Ac, respectively) and expressed it under the control of a constitutive promoter in chickpea (cv. DCP92-3) to assess its effect on gram pod borer. A total of six transgenic chickpea shoots were established by grafting into mature fertile plants. The in vitro regenerated (organogenetic) shoots were selected based on antibiotic kanamycin monosulfate (100 mg/L) with transformation efficiency of 0.076%. Three transgenic events were extensively studied based on gene expression pattern and insect mortality across generations. Protein expression in pod walls, immature seeds and leaves (pre- and postflowering) were estimated and expression in pre-flowering stage was found higher than that of post-flowering. Analysis for the stable integration, expression and insect mortality (detached leaf and whole plant bioassay) led to identification of efficacious transgenic chickpea lines. The chimeric cry1Aabc expressed in chickpea is effective against gram pod borer and generated events can be utilized in transgenic breeding program. [ABSTRACT FROM AUTHOR]

Rice blast resistant gene, Pi54 cloned from rice line, Tetep, is effective against diverse isolates of Magnaporthe oryzae. In this study, we prospected the allelic variants of the dominant blast resistance gene from a set of 92 rice lines to determine the nucleotide diversity, pattern of its molecular evolution, phylogenetic relationships and evolutionary dynamics, and to develop allele specific markers. High quality sequences were generated for homologs of Pi54 gene. Using comparative sequence analysis, InDels of variable sizes in all the alleles were observed. Profiling of the selected sites of SNP (Single Nucleotide Polymorphism) and amino acids (N sites ≥ 10) exhibited constant frequency distribution of mutational and substitutional sites between the resistance and susceptible rice lines, respectively. A total of 50 new haplotypes based on the nucleotide polymorphism was also identified. A unique haplotype (H_3) was found to be linked to all the resistant alleles isolated from indica rice lines. Unique leucine zipper and tyrosine sulfation sites were identified in the predicted Pi54 proteins. Selection signals were observed in entire coding sequence of resistance alleles, as compared to LRR domains for susceptible alleles. This is a maiden report of extensive variability of Pi54 alleles in different landraces and cultivated varieties, possibly, attributing broad-spectrum resistance to Magnaporthe oryzae. The sequence variation in two consensus region: 163 and 144 bp were used for the development of allele specific DNA markers. Validated markers can be used for the selection and identification of better allele(s) and their introgression in commercial rice cultivars employing marker assisted selection. [ABSTRACT FROM AUTHOR]

Rice blast disease caused by the fungus, Magnaporthe oryzae, is one of the most devastating diseases of rice. Deciphering molecular mechanism of host-pathogen interactions is of great importance in devising disease management strategies. Transcription being the first step for gene regulation in eukaryotes, basic understanding of the transcriptome is sine qua non for devising effective management strategy. The availability of genome sequences of rice and M. oryzae has facilitated the process to a large extent. The current review summarizes recent understanding of rice-blast pathosystem, application of transcriptomics approaches to understand the interactions employing different platforms, major determinants in the interaction and possibility of using certain candidate for conditioning enhanced disease resistance (Effector Triggered Immunity and PAMP Triggered Immunity) and downstream signalling in rice. A better understanding of the interaction elements and effective strategies hold potential to reduce yield losses in rice caused by M. oryzae.