Groundnut Bud Necrosis Disease (GBND) caused by Groundnut Bud Necrosis Virus (GBNV) has been cons... more Groundnut Bud Necrosis Disease (GBND) caused by Groundnut Bud Necrosis Virus (GBNV) has been considered as one of the major virus diseases in Andhra Pradesh. Survey conducted in groundnut growing areas of Anantapur district during kharif and rabi 2013-14 and in Karimnagar and Warangal districts during rabi 2013-14 season revealed the natural occurrence of GBND in different mandals with an overall average incidence of 3.47 per cent. Higher incidence of GBND was observed in Anantapur (8.50 per cent) followed by Karimnagar (0.97 per cent) and Warangal (0.94 per cent) districts. Groundnut cultivar K-6 was grown extensively in all the districts surveyed. The infected groundnut leaf samples collected from Anantapur district tested positive when subjected to DAC-ELISA
Cotton leafroll dwarf virus (CLRDV) is an emerging virus in cotton production in Georgia and seve... more Cotton leafroll dwarf virus (CLRDV) is an emerging virus in cotton production in Georgia and several other Southeastern states in the USA. To better understand the genetic diversity of the virus population, the near complete genome sequences of six isolates from Georgia and one from Alabama were determined. The isolates sequenced were 5,866 nucleotides with seven open reading frames (ORFs). The isolates from Georgia were >94% identical with other isolates from the USA and South America. In the silencing suppressor protein (P0), at amino acid position 72, the isolates from Georgia and Alabama had a valine (V), similar to resistant-breaking ‘atypical’ genotypes in South America, while the Texas isolate had isoleucine (I), similar to the more aggressive ‘typical’ genotypes of CLRDV. At position 120, arginine (R) is unique to Georgia and China isolates, but absent in Alabama, Texas and South American isolates. Ten potential recombinant events were detected in the isolates sequenced. ...
Cotton leafroll dwarf disease (CLRDD) caused by cotton leafroll dwarf virus (CLRDV) is an emergin... more Cotton leafroll dwarf disease (CLRDD) caused by cotton leafroll dwarf virus (CLRDV) is an emerging threat to cotton production in the United States. The disease was first reported in Alabama in 2017 and subsequently has been reported in 10 other cotton producing states in the United States, including Georgia. A field study was conducted at field sites near Tifton, Georgia in 2019 and 2020 to evaluate leaf gas exchange, chlorophyll fluorescence, and leaf temperature responses for a symptomatic cultivar (diseased plants observed at regular frequency) at multiple stages of disease progression and for asymptomatic cultivars (0% disease incidence observed). Disease-induced reductions in net photosynthetic rate (An, decreased by 63–101%), stomatal conductance (gs, decreased by 65–99%), and efficiency of the thylakoid reactions (32–92% decline in primary photochemistry) were observed, whereas leaf temperature significantly increased by 0.5–3.8°C at advanced stages of the disease. Net photo...
Iris yellow spot, caused by Iris yellow spot orthotospovirus (IYSV) (Genus: Orthotospovirus, Fami... more Iris yellow spot, caused by Iris yellow spot orthotospovirus (IYSV) (Genus: Orthotospovirus, Family: Tospoviridae), is an important disease of Allium spp. The complete N gene sequences of 142 IYSV isolates of curated sequence data from GenBank were used to determine the genetic diversity and evolutionary pattern. In silico restriction fragment length polymorphism (RFLP) analysis, codon-based maximum likelihood studies, genetic differentiation and gene flow within the populations of IYSV genotypes were investigated. Bayesian phylogenetic analysis was carried out to estimate the evolutionary rate. In silico RFLP analysis of N gene sequences categorized IYSV isolates into two major genotypes viz., IYSV Netherlands (IYSVNL; 55.63%), IYSV Brazil (IYSVBR; 38.73%) and the rest fell in neither group [IYSV other (IYSVother; 5.63%)]. Phylogenetic tree largely corroborated the results of RFLP analysis and the IYSV genotypes clustered into IYSVNL and IYSVBR genotypes. Genetic diversity test rev...
Cotton leafroll dwarf disease (CLRDD), caused by the aphid-borne Cotton leafroll dwarf virus (CLR... more Cotton leafroll dwarf disease (CLRDD), caused by the aphid-borne Cotton leafroll dwarf virus (CLRDV; genus, Polerovirus ; family, Luteoviridae ), has been recently reported from the major cotton-growing regions of the United States. Here, we present the nearly complete genome sequence of a CLRDV isolate from cotton in Georgia.
International Journal of Current Microbiology and Applied Sciences, Oct 10, 2017
GBNV belongs to family Tospoviridae and responsible for causing Groundnut Bud Necrosis Disease (G... more GBNV belongs to family Tospoviridae and responsible for causing Groundnut Bud Necrosis Disease (GBND) in groundnut (Reddy, 1991). GBNV is an economically important Tospovirus and its distribution is confined to South and Southeast Asian countries namely China, India, Nepal, Pakistan, Sri Lanka and Thailand (Dwivedi et al., 1995). The name Tospovirus (renamed Orthotospovirus) (Adams et al., 2017, Briese et al., 2016) was given after the discovery of Tomato spotted wilt virus (TSWV) in Australia in 1915.The disease was first recorded in India at Indian Agricultural Research Institute in 1949 (Reddy et al.,
International Journal of Pure & Applied Bioscience, 2017
Gene editing of living organisms has been tired by scientists since the discovery of DNA. Earlier... more Gene editing of living organisms has been tired by scientists since the discovery of DNA. Earlier approaches of gene editing was using oligonucleotides, self-splicing introns etc. Zinc Finger Nucleases (ZFN’s) and TALENs are effective but not widely adapted. The CRISPR (Clustered Regularly Interspaced Palindromic Repeat) – Cas (CRISPRassociated) is hundreds of millions of years old found in bacteria as survival mechanism against infection of viruses. The mechanism of CRISPR-Cas was understood only in early 2000s. This review presents overview of CRISPR technology and its applications against Plant Pathogens including Fungi, Bacteria and Viruses.
Potato mop-top virus (PMTV; Genus: Pomovirus; Family: Virgaviridae) is a soil-borne RNA virus tha... more Potato mop-top virus (PMTV; Genus: Pomovirus; Family: Virgaviridae) is a soil-borne RNA virus that is an emerging issue impacting potato production in the US. PMTV is known to exist as two distinct strains; however, there is limited information on the population structure, strain incidence and distribution in the U.S. The complete genome of six isolates of PMTV collected from three states in the USA were sequenced, analyzed, and compared with a previously characterized isolate from Washington and all known PMTV sequences available in GenBank. Genome-wide nucleotide sequence identities of the U.S. isolates ranged from 96% to 100%. Based on the CPRT amino acid sequence, all the U.S. isolates clustered with known severe (S) strains. Genetic diversity test showed that the S strain to be more diverse than the mild (M) strain and the PMTV recombinant strain. Population selection analysis revealed that most of the codons were generally negatively selected in the PMTV isolates studied. However, positive selection was detected at codon 689 in the RT domain, which could be an adaptation to facilitate vector transmission and to overcome host plant resistance. The sequence characteristics and the observed genetic diversity would be useful in developing improved virus diagnostics to detect virus in aerial plant parts, tubers, soil and the soil-borne vector.
In the United States, cotton leafroll dwarf disease, caused by Cotton leafroll dwarf virus 8 (CLR... more In the United States, cotton leafroll dwarf disease, caused by Cotton leafroll dwarf virus 8 (CLRDV, genus Polerovirus, family Luteoviridae) was first reported from cotton (Gossypium 9 hirsutum L.
Allium tuberosum L., commonly known as garlic chives, is an important spice in northeastern India... more Allium tuberosum L., commonly known as garlic chives, is an important spice in northeastern India as well as in many other parts of the world. Iris yellow spot virus (IYSV; genus Tospovirus, family Bunyaviridae) is an important pathogen of onion (4) and other related Alliums such as garlic (3) and leek (2). During April 2013, symptoms potentially induced by IYSV such as chlorotic and straw-colored spindle-like lesions were observed on leaves of A. tuberosum accession Hanzong Winter (CGN 20779) plants in the wild species garden at the Directorate of Onion and Garlic Research (DOGR), Rajgurunagar, Pune, Maharashtra, India. Ten plant samples of A. tuberosum were randomly collected from the wild species garden and the upper, middle, and lower portions of the leaves were pooled and tested by double-antibody sandwich (DAS)-ELISA using a commercially available kit (Agdia Inc., Elkhart, IN) for IYSV. All of them showed positive results for IYSV incidence. Total RNA from the ELISA positive l...
Groundnut Bud Necrosis Disease (GBND) caused by Groundnut Bud Necrosis Virus (GBNV) has been cons... more Groundnut Bud Necrosis Disease (GBND) caused by Groundnut Bud Necrosis Virus (GBNV) has been considered as one of the major virus diseases in Andhra Pradesh. Survey conducted in groundnut growing areas of Anantapur district during kharif and rabi 2013-14 and in Karimnagar and Warangal districts during rabi 2013-14 season revealed the natural occurrence of GBND in different mandals with an overall average incidence of 3.47 per cent. Higher incidence of GBND was observed in Anantapur (8.50 per cent) followed by Karimnagar (0.97 per cent) and Warangal (0.94 per cent) districts. Groundnut cultivar K-6 was grown extensively in all the districts surveyed. The infected groundnut leaf samples collected from Anantapur district tested positive when subjected to DAC-ELISA
Cotton leafroll dwarf virus (CLRDV) is an emerging virus in cotton production in Georgia and seve... more Cotton leafroll dwarf virus (CLRDV) is an emerging virus in cotton production in Georgia and several other Southeastern states in the USA. To better understand the genetic diversity of the virus population, the near complete genome sequences of six isolates from Georgia and one from Alabama were determined. The isolates sequenced were 5,866 nucleotides with seven open reading frames (ORFs). The isolates from Georgia were >94% identical with other isolates from the USA and South America. In the silencing suppressor protein (P0), at amino acid position 72, the isolates from Georgia and Alabama had a valine (V), similar to resistant-breaking ‘atypical’ genotypes in South America, while the Texas isolate had isoleucine (I), similar to the more aggressive ‘typical’ genotypes of CLRDV. At position 120, arginine (R) is unique to Georgia and China isolates, but absent in Alabama, Texas and South American isolates. Ten potential recombinant events were detected in the isolates sequenced. ...
Cotton leafroll dwarf disease (CLRDD) caused by cotton leafroll dwarf virus (CLRDV) is an emergin... more Cotton leafroll dwarf disease (CLRDD) caused by cotton leafroll dwarf virus (CLRDV) is an emerging threat to cotton production in the United States. The disease was first reported in Alabama in 2017 and subsequently has been reported in 10 other cotton producing states in the United States, including Georgia. A field study was conducted at field sites near Tifton, Georgia in 2019 and 2020 to evaluate leaf gas exchange, chlorophyll fluorescence, and leaf temperature responses for a symptomatic cultivar (diseased plants observed at regular frequency) at multiple stages of disease progression and for asymptomatic cultivars (0% disease incidence observed). Disease-induced reductions in net photosynthetic rate (An, decreased by 63–101%), stomatal conductance (gs, decreased by 65–99%), and efficiency of the thylakoid reactions (32–92% decline in primary photochemistry) were observed, whereas leaf temperature significantly increased by 0.5–3.8°C at advanced stages of the disease. Net photo...
Iris yellow spot, caused by Iris yellow spot orthotospovirus (IYSV) (Genus: Orthotospovirus, Fami... more Iris yellow spot, caused by Iris yellow spot orthotospovirus (IYSV) (Genus: Orthotospovirus, Family: Tospoviridae), is an important disease of Allium spp. The complete N gene sequences of 142 IYSV isolates of curated sequence data from GenBank were used to determine the genetic diversity and evolutionary pattern. In silico restriction fragment length polymorphism (RFLP) analysis, codon-based maximum likelihood studies, genetic differentiation and gene flow within the populations of IYSV genotypes were investigated. Bayesian phylogenetic analysis was carried out to estimate the evolutionary rate. In silico RFLP analysis of N gene sequences categorized IYSV isolates into two major genotypes viz., IYSV Netherlands (IYSVNL; 55.63%), IYSV Brazil (IYSVBR; 38.73%) and the rest fell in neither group [IYSV other (IYSVother; 5.63%)]. Phylogenetic tree largely corroborated the results of RFLP analysis and the IYSV genotypes clustered into IYSVNL and IYSVBR genotypes. Genetic diversity test rev...
Cotton leafroll dwarf disease (CLRDD), caused by the aphid-borne Cotton leafroll dwarf virus (CLR... more Cotton leafroll dwarf disease (CLRDD), caused by the aphid-borne Cotton leafroll dwarf virus (CLRDV; genus, Polerovirus ; family, Luteoviridae ), has been recently reported from the major cotton-growing regions of the United States. Here, we present the nearly complete genome sequence of a CLRDV isolate from cotton in Georgia.
International Journal of Current Microbiology and Applied Sciences, Oct 10, 2017
GBNV belongs to family Tospoviridae and responsible for causing Groundnut Bud Necrosis Disease (G... more GBNV belongs to family Tospoviridae and responsible for causing Groundnut Bud Necrosis Disease (GBND) in groundnut (Reddy, 1991). GBNV is an economically important Tospovirus and its distribution is confined to South and Southeast Asian countries namely China, India, Nepal, Pakistan, Sri Lanka and Thailand (Dwivedi et al., 1995). The name Tospovirus (renamed Orthotospovirus) (Adams et al., 2017, Briese et al., 2016) was given after the discovery of Tomato spotted wilt virus (TSWV) in Australia in 1915.The disease was first recorded in India at Indian Agricultural Research Institute in 1949 (Reddy et al.,
International Journal of Pure & Applied Bioscience, 2017
Gene editing of living organisms has been tired by scientists since the discovery of DNA. Earlier... more Gene editing of living organisms has been tired by scientists since the discovery of DNA. Earlier approaches of gene editing was using oligonucleotides, self-splicing introns etc. Zinc Finger Nucleases (ZFN’s) and TALENs are effective but not widely adapted. The CRISPR (Clustered Regularly Interspaced Palindromic Repeat) – Cas (CRISPRassociated) is hundreds of millions of years old found in bacteria as survival mechanism against infection of viruses. The mechanism of CRISPR-Cas was understood only in early 2000s. This review presents overview of CRISPR technology and its applications against Plant Pathogens including Fungi, Bacteria and Viruses.
Potato mop-top virus (PMTV; Genus: Pomovirus; Family: Virgaviridae) is a soil-borne RNA virus tha... more Potato mop-top virus (PMTV; Genus: Pomovirus; Family: Virgaviridae) is a soil-borne RNA virus that is an emerging issue impacting potato production in the US. PMTV is known to exist as two distinct strains; however, there is limited information on the population structure, strain incidence and distribution in the U.S. The complete genome of six isolates of PMTV collected from three states in the USA were sequenced, analyzed, and compared with a previously characterized isolate from Washington and all known PMTV sequences available in GenBank. Genome-wide nucleotide sequence identities of the U.S. isolates ranged from 96% to 100%. Based on the CPRT amino acid sequence, all the U.S. isolates clustered with known severe (S) strains. Genetic diversity test showed that the S strain to be more diverse than the mild (M) strain and the PMTV recombinant strain. Population selection analysis revealed that most of the codons were generally negatively selected in the PMTV isolates studied. However, positive selection was detected at codon 689 in the RT domain, which could be an adaptation to facilitate vector transmission and to overcome host plant resistance. The sequence characteristics and the observed genetic diversity would be useful in developing improved virus diagnostics to detect virus in aerial plant parts, tubers, soil and the soil-borne vector.
In the United States, cotton leafroll dwarf disease, caused by Cotton leafroll dwarf virus 8 (CLR... more In the United States, cotton leafroll dwarf disease, caused by Cotton leafroll dwarf virus 8 (CLRDV, genus Polerovirus, family Luteoviridae) was first reported from cotton (Gossypium 9 hirsutum L.
Allium tuberosum L., commonly known as garlic chives, is an important spice in northeastern India... more Allium tuberosum L., commonly known as garlic chives, is an important spice in northeastern India as well as in many other parts of the world. Iris yellow spot virus (IYSV; genus Tospovirus, family Bunyaviridae) is an important pathogen of onion (4) and other related Alliums such as garlic (3) and leek (2). During April 2013, symptoms potentially induced by IYSV such as chlorotic and straw-colored spindle-like lesions were observed on leaves of A. tuberosum accession Hanzong Winter (CGN 20779) plants in the wild species garden at the Directorate of Onion and Garlic Research (DOGR), Rajgurunagar, Pune, Maharashtra, India. Ten plant samples of A. tuberosum were randomly collected from the wild species garden and the upper, middle, and lower portions of the leaves were pooled and tested by double-antibody sandwich (DAS)-ELISA using a commercially available kit (Agdia Inc., Elkhart, IN) for IYSV. All of them showed positive results for IYSV incidence. Total RNA from the ELISA positive l...
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