First genome analysis and molecular characterization of Chickpea chlorotic dwarf virus Egyptian isolate infecting squash

Abstract

This study aims to identifying and characterizing some molecular properties of geminiviruses co-infection in squash field crop cultivated in Egypt. Squash crops observed to be heavily infected with several insect vectors, also severe chlorosis and stunting was observed. Electron microscopic analysis has revealed geminate capsid particles which indicate the infection of Geminiviruses, especially SqLCV which represent an economic problem to squash filed crop in Egypt. We have investigated possible mixed infections with different plant viruses associated with chlorotic stunt diseases and or other genus groups of geminiviruses. The main objective of this study is to investigate the recombination events, possible recombinants and variants among these genera in the same family differing in vector transmission. This is the first report of the molecular characterization, phylogenetic analysis and putative recombination events of the full length genome of the Chickpea Chlorotic Dwarf Mastrevirus in Egypt. And the first report of co-infection with another begomovirus infecting squash plants. A full length clone of both viruses were isolated and characterized at the molecular level. The complete nucleotide sequence of DNA-A was determined (2,572 bp) and submitted to the genbank under accession no. KF692356. The isolate from Egypt has about 97.8 % homology with the Chickpea chlorotic dwarf virus (CpCDV) isolate from Syria DNA-A isolate FR687959, a 83.2 % homology with the Sudan isolate AM933134 and a 82.7 % homology with Pakistan isolate FR687960. To best of our knowledge this is the first report of complete genome of CpCDV that infect squash plants in Egypt and worldwide.

Morpho-molecular characterization of landraces/wild genotypes of Cicer for Biotic/ Abiotic stresses

“…Thus, chickpea plays an important role in sustaining cereal based cropping system, which is the lifeline for food security in the country. The major constraints for the realization of the potential yield of chickpea are various diseases such as Fusarium wilt, root rot, Ascochyta blight, Botrytis grey mould, insect pest pod borer (Helicoverpa) and abiotic stresses namely terminal drought, high temperature during reproductive stage and cold sensitivity during the vegetative and flowering stages (Fahmy et al, 2015;Madrid et al, 2014;Varshney and Thudi, 2014).…”

Deep Sequencing Data and Infectivity Assays Indicate that Chickpea Chlorotic Dwarf Virus is the Etiological Agent of the “Hard Fruit Syndrome” of Watermelon

“…Cajanus cajan , Dolichus lablab , Rinchosia minima ) in Sudan [ 5 ]; CpCDV was also detected in Beta vulgaris in Iran [ 6 ], in papaya ( Carica papaya ) in Burkina Faso [ 7 ], in some economically important Solanaceae such as pepper ( Capsicum annuum ) in Oman [ 8 ], and tomato ( Lycopersicon esculentum ) in Pakistan and Burkina Faso [ 7 , 9 ], in Malvaceae as okra ( Abelmoschus esculentus ) in Pakistan [ 10 ], and cotton ( Gossypium hirsutum ) in India [ 11 ]. CpCDV infects also other cucurbits beside watermelon [ 2 ], including squash ( Cucurbita pepo ) in Egypt [ 12 ] and cucumber ( Cucumis sativus ) in Pakistan [ 13 ]. CpCDV, as with other geminiviruses, is considered to be a dangerous emerging virus, with a high potential of recombination and spread in new areas infecting new crops [ 14 , 15 ].…”

Construction of an Infectious Chimeric Geminivirus by Molecular Cloning Based on Coinfection and Recombination

“…Although by exchanging/interchanging CP genes tween two divergent genera of geminiviridae leading to a transition in vector species from whitefly to leafhopper (Briddon et al, 1990). Recently, Fahmy et al (2015) reported a coinfection of CpCDV-CLCuBuV in a non-host species of dicot infecting mastrevirus i.e, squash. Full length complete genome of the CpCDV reported first time infecting squash in Egypt with its supposed recombination events beside molecular characterization and phylogenetic analysis.…”

“…But in these reports the host is different every time belonging to different plant families. Mubin et al (2012) reported this mastrebegomo coinfection in weed (Family: Asteraceae) whereas Manzoor et al (2014) and Fahmy et al (2015) affirmed in cotton (Family: Malvaceae) and squash (Family: Cucurbitaceae), respectively. So, in order to investigate this aforesaid feature, we planned an experiment to remove coat protein (CP) gene of CpCDV (Genus: Mastrevirus) and in place of it insert the CP gene of CLCuBuV (Genus: Begomovirus) in order to make 'MastreBegomo chimera (Both viruses belonging to the same family Geminiviridae).…”