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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]

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]

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.