Molecular Studies on the Transmission of Indian Cassava Mosaic Virus (ICMV) and Sri Lankan Cassava Mosaic Virus (SLCMV) in Cassava by Bemisia tabaci and Cloning of ICMV and SLCMV Replicase Gene from Cassava

Abstract

Cassava mosaic disease, caused by cassava mosaic geminiviruses are transmitted by Bemisia tabaci. The B. tabaci adults from colonies reared on virus free cassava plant produced from apical meristem culture was studied to determine their ability to transmit Indian cassava mosaic virus (ICMV) and Sri Lankan cassava mosaic virus (SLCMV) from cassava to cassava. Virus free plants were confirmed by polymerase chain reaction (PCR) using geminivirus degenerate primers. The virus acquisition access period (AAP) of 48 h on virus infected cassava leaves and 48 h virus inoculation access periods on virus free healthy leaves were investigated. Both ICMV and SLCMV were absolutely transmitted by whiteflies reared on cassava. Virus specific primers were designed in the replicase region and used to detect virus in B. tabaci after different AAP. The PCR amplified replicase genes from virus transmitted cassava leaves were cloned the plasmid DNA was isolated from a recombinant colony of E. coli DH5α after their confirmation by colony PCR and sequenced them. The nucleotide sequences obtained from automated DNA sequencing were confirmed as ICMV and SLCMV replicase gene after homology searching by BLAST and found to be a new isolates. The nucleotide sequences of new isolates were submitted in GenBank (accession number JN652126 and JN595785).

Surveillance for Sri Lankan cassava mosaic virus (SLCMV) in Cambodia and Vietnam one year after its initial detection in a single plantation in 2015

“…SLCMV diagnosis was carried out using specific primers based on the AC1 ( replicase ) gene of SLCMV reported by Duraisamy et al . [12]. Thermal cycling consisted of an initial denaturation at 94°C for 5 minutes, followed by 40 cycles of 2 minutes at 94°C, annealing at 55°C for 30 seconds, 72°C for 1 minute, followed by a final extension of 5 minutes at 72°C.…”

“…The recent report of SLCMV in Cambodia expands on previous identifications in Sri Lanka and India [1, 9–11]. Like other CMGs, SLCMV is transmitted by the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), and through the movement of infected planting materials [12]. With ACMV, plants grown from infected cuttings are more seriously affected than those infected by the whitefly vector [13].…”

In Vitro Regeneration of Plectranthus Edulis (Vatke) from Leaf Derived Callus

“…Among all treatments used, highest mean shoot number (58.68±6.57) and number of shoots per explants (129) were obtained on MS medium supplemented with 0.5 mg/l BAP + 0.4 mg/l GA3. Duraisamy et al (2012) also reported that maximum mean number of shoots per explant (6.3±0.09) was obtained using MS medium supplemented with 0.02 mg/l GA3 + 0.1 mg/l BAP on apical meristem cultures of cassava. Tsgaw and Feyisaa (2014) obtained the maximum mean number of shoots per explant (7.2) of P. edulis on MS medium supplemented with 1.0 mg/l KIN + 0.1 mg/l NAA.…”

Development of a triple antibody sandwich enzyme-linked immunosorbent assay for cassava mosaic disease detection using a monoclonal antibody to Sri Lankan cassava mosaic virus

“…Several molecular and serology-based methods have been employed for the detection of CMBs such as PCR [ 20 ], multiplex PCR [ 21 ], real-time PCR [ 22 ], immunosorbent electromicroscopy [ 23 ], double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) [ 24 ] and triple antibody sandwich-ELISA (TAS-ELISA) [ 25 ]. For SLCMV, methods such as PCR [ 26 – 28 ], multiplex PCR [ 29 , 30 ], rolling circle amplification (RCA) [ 12 ] and plate-trapped antigen-ELISA (PTA-ELISA) [ 15 ] have been described. Although molecular-based methods are known to be more sensitive, ELISA is generally more suitable for routine and large-scale CMD screening, due to its simplicity, high throughput and cost-effectiveness.…”