Scientist, Plant Pathology
ACHARYA N.G.RANGA AGRICULTURAL UNIVERSITY
Completed B.Sc in Agriculture, M.Sc (Agiculture) and Ph.D (Plant Pathology) at Acharya N.G.Ranga Agricultural University, Guntur, Andhra Pradesh, India
Ph.D in Plant Pathology
Fungal pathology, Biological control, Host Resistance
Sugarcane yellow leaf disease is an important disease and spreading at alarming level devastating the sugarcane cultivation at nation wide. As a measure of managing the disease, it is very essential to study the alternate hosts that acts as reservoirs for the virus.
T.M. Hemalatha, B.V. Bhaskara Reddy, R. Sarada Jayalakshmi, S.R. Koteswara Rao, M. Hemanth Kumar, and G. Mohan Naidu Agricultural Research Communication Center
Background: Among the diseases of sugarcane, Sugarcane yellow leaf disease (YLD) is one of the most prevalent diseases of sugarcane posing serious threat to the sugarcane cultivation worldwide. The current study aims at studying the distribution of SCYLV in the major sugarcane-growing of Andhra Pradesh and determining sequence identities, sequence variations and phylogenetic relationships between the SCYLV isolates reported earlier from India and worldwide. Methods: ORF1 and ORF2 regions of the viral genome coding for RNA dependent RNA Polymerase (RdRP) was amplified from twelve of the samples using the gene specific primers viz., SCYLV-F3 and SCYLV-R3. The ORF1 and ORF2 regions were studied for sequence similarity at nucleotide and aminoacid level and phylogentic relationships were established with the other SCYLV isolates. Result: The multiple sequence analysis of the isolates under the study with 22 similar sequences of SYLCV isolates reported from India and worldwide revealed 90.6-100% identities with IND, REU, BRA, CHN, HAW, CUB, COL and PER genotypes reported worldwide. The Indian isolates showed close phylogenetic relationship with the CUB and COL isolates. Hence it was confirmed from the study that SCYLV isolates collected from major sugarcane growing regions of Andhra Pradesh closely related to SCYLV-CUB and SCYLV-COL genotypes.
Pola Chandini, Madem Gurivi Reddy, Bommu Veera Bhaskara Reddy, Tirukoillur Mohanbabu Hemalatha, Madduri Subramanya Venkata Chalam, and Mahal Reddy Kumar Diva Enterprises Private Limited
T. M. Hemalatha, M. Shantipriya, D. Vijay Kumar Naik, B. V. Bhaskara Reddy, M. Gurivi Reddy, L. Madhaviltha, M. Hemanth Kumar, B. Vajantha, N. V. Sarala, and K. R. Tagore Scientific Societies
Pearl millet [Pennisetum glaucum (L).R.Br.] also known as bajra, is one of the oldest millets and is cultivated in dry regions of arid and semi-arid tropics where no other cereal can be successfully grown. Pearl millet cultivation in India accounts for about two-thirds of millet production and is the fourth most cultivated food crop after rice, wheat and maize in India (Reddy et al. 2021a). In February 2021, the typical symptoms of stunting, phyllody and little leaf were observed after 25-30 days after sowing pearl millet seeds at Agricultural Research Station in Perumallapalle, Tirupati, India (Fig.1 A-C). The disease incidence was recorded up to 20% in the sampling regions. Total DNA was extracted from two symptomatic and two asymptomatic plant samples using CTAB DNA extraction method (Murray and Thompson, 1980). The extracted DNA was amplified in direct PCR and nested PCR assay using phytoplasma 16S rRNA universal primer pairs P1/P7 and R16F2n/R16R2 (Gundersen and Lee.1996) and secA gene with secAfor1/SecArev3 and SecAfor2/SecArev3 primer pairs (Hodgetts et al. 2008). 16SrRNA (1.25 kb) and secA (600 bp) gene amplicons were obtained from two symptomatic samples by nested PCR. No amplicons were produced with DNA from healthy leaf samples. Nested PCR amplified products (1.25 kb and 600 bp) from the symptomatic samples corresponding to the F2nR2 region of 16S rRNA and secA were directly sequenced at automated DNA sequencing facility (Eurofin Genomics India Pvt., Ltd Bangalore) and sequence data was deposited to NCBI GenBank with accession number ON005559 and ON067810. BLAST analysis revealed that pearl millet phytoplasma strain shared 100% sequence identity in 16Sr RNA and secA genes to 'Canditatus Phytoplasma aurantifolia' related strains (Acc. Nos. OM616883 and MT952965) from India. The subgroup was identified as 16SrII-D using the iPhyClassifier based on the virtual RFLP pattern derived from the query 16S rDNA F2nR2 fragment (Zhao et al. 2009). The virtual RFLP pattern is similar to the reference pattern of 16SrII-D (Y10096) with similarity coefficient 1.00. Phylogenetic analysis of 16S rRNA and secA gene sequences using MEGA version 7.0 revealed that the pearl millet phytoplasma strain clustered with 'Ca. P. aurantifolia' isolates of 16SrII-D subgroup. (Fig.1D-E) Earlier, one of 16SrI-B-phytoplasma strain (HM 134245) associated with green ear disease of pearl millet was reported in North India (Kumar et al. 2010). In this study, we reported the association of 16SrII-D subgroup phytoplasma with little leaves and witches'-broom disease of pearl millet in South India. Phytoplasmas belonging to the 16SrII-D subgroup have a wide range of hosts, including the agricultural and horticultural crops (Reddy et al., 2021b). Hence, this is the first report of 'Ca. P aurantifolia' infection in bajra in South India. The increase in the spread of 16SrII-D sub group phytoplasma diseases and the expansion of the host range strongly suggest further studies on the epidemiology of the dynamic dissemination of this disease in India.
D. Vijay Kumar Naik, B. V. Bhaskara Reddy, L. Prasanthi, M. Guruvi Reddy, G. Sandhya, T. M. Hemalatha, and R. Sarada Jayalakshi Devi Wiley
D. Vijay Kumar Naik, B.V. Bhaskara Reddy, R. Sarada Jayalakshmi Devi, L. Prasanthi, R. Lakshminarayana Vemireddy, Akkari Srividhya, B.H. Chaithanya, T.M. Hemalatha, and K. Sailaja Agricultural Research Communication Center
Background: The productivity of blackgram is affected by many biotic and abiotic stresses. Among the biotic stresses, yellow mosaic disease (YMD) cause severe yield loss and it is caused by four distinct viruses (belongs to genus begomovirus) collectively known as yellow mosaic virus (YMV). Hence there is need to characterize various YMV isolates associated with blackgram in Andhra Pradesh. Methods: YMV infected blackgram samples were collected from East Godavari, Kurnool and Prakasam districts of Andhra Pradesh. The Rolling Circle Amplification (RCA) based full length MYMIV DNA-A and MYMV DNA-B of three isolates were cloned and sequenced. Result: Nucleotide sequence of full length DNA-A of MYMIV-East Godavari isolate showed greater than 96% similarity at nucleotide and greater than 90% at amino acid level with other MYMIV isolates in NCBI database. The complete DNA-A nucleotide sequence of MYMIV-Kurnool and MYMIV-Prakasam isolates shared greater than 99% similarity at nucleotide and greater than 98% at amino acid level with other MYMIV isolates. The complete nucleotide sequence of MYMV DNA-B of three isolates (East Godavari, Kurnool and Prakasam) had greater than 97% homology with other MYMV DNA-B isolates from database. The predicted amino acid sequence of MYMV DNA-B of three isolates shared greater than 96% homology with other MYMV-B isolates. The common region (CR) sequence similarity between MYMIV-As and MYMV-Bs of East Godavari and Kurnool isolates was 76.4% and 78.3% with Prakasam isolate. The divergence between the MYMIV-A and MYMV-B of present three isolates (East Godavari, Kurnool and Prakasam) under study were ranged from 22.2 to 22.6%.
T. M. Hemalatha, D. Vijay Kumar Naik, L. Madhavilatha, B. V. Bhaskara Reddy, M. Shanti Priya, M. Gurivi Reddy, M. Hemanth Kumar, N. V. Sarala, B. Vajantha, and K. R. Tagore Wiley
Praveen Kona, M Hemanth Kumar, K H P Reddy, T M Hemalatha, D M Reddy, N P Eswar Reddy, and P Latha Springer Science and Business Media LLC
-Developed protocol for serological detection of sugarcane yellow leaf virus in infected samples of sugarcane.
-Developed sugarcane somaclone (2016T7) resistant to sugarcane yellow leaf disease.