Palash Deb Nath

• Doctor of Philosophy
• Assam Agricultural University

Soybean (Glycine max. L.) plants with virus-like systemic mosaic and mottling symptoms were observed in both experimental and commercial fields in Assam State, India. Begomo and Carlaviruses are the most destructive viruses infecting legume crops in India. A diagnostic survey was carried out to assess the prevalence of major viruses in soybean grow...

Citrus tristeza virus (CTV) is found worldwide wherever citrus is cultivated, causing Citrus tristeza disease resulting in significant yield losses and sometimes the death of the plant. Transgenic citrus plants encoding CTV gene sequences have shown to exhibit pathogen-derived resistance to CTV. Exogenous application of double-stranded RNA (dsRNA)...

In recent decades, soybean production has increased tremendously due to high demand of its oil- and protein-rich seeds. Despite its high economic importance, soybean crop is threatened by a wide range of biotic agents affecting the yield. Plant pathogenic fungi are a significant group of organisms that endanger the health of soybeans. Fungal diseas...

Pumpkin (Cucurbita moschata Duch.), a prominent cucurbitaceous vegetable consumed in India is more vulnerable to viral infections under field conditions. Plant viruses are considered major constraints for cucurbit production. Management of viral diseases is crucial for increasing pumpkin yields and value. Viral diseases of pumpkins are widespread i...

The cucurbits belong to the family Cucurbitaceous (gourd family) under the order Cucurbit ales which include many economically important vegetable and fruit species. Among various factors, viruses are one of the important factors reducing in quantity as well as quality of cucurbits. These crops are severely affected by the cucurbit mosaic disease w...

Aim: The study aims to standardize a Real-Time LAMP assay for effective, highly sensitive, and rapid detection of BBTV in North-east India. Methodology: Forty samples of banana showing BBTV like symptoms were collected from Assam, India and subjected to conventional PCR for confirmation. Six sets of BBTV LAMP primers were designed and the PCR posit...

King chilli crop of Assam, India infected with Chilli veinal mottle virus (ChiVMV) belongs to genus potyvirus of the family potyviridae suffered from necrosis of leaves, leaf puckering, filiform leaves and eventually plant death. King chilli crop particularly suffers from decline complex due to high incidence of viral diseases. Prominent distributi...

Aim: To record the prevalence, detection, molecular and biological characterization of phytoplasma associated with brinjal little leaf disease in Assam and its management. Methodology: Roving survey was conducted during the 2018-2020 brinjal growing seasons to record the disease incidence and symptoms associated with the disease. Insect and dodder...

Northeast (NE) India is known to produce different kinds of citrus species. Citrus tristeza virus (CTV), brown citrus aphid (Toxoptera citricidus) transmitted closterovirus, is a major problem to cause citrus decline in this region. CTV has destroyed more than one million of citrus trees in India. CTV contains flexuous filamentous particles (2000 ×...

Background: Different communities in the state of Assam produces particular fermented and non-fermented products like rice beer, sweets and snacks etc. using rice as a substrate. Traditionally, important alcoholic beverages harbour a myriad of microbes including contaminants. The starter culture is made of rice and herbal combinations and believed...

Potato leafroll virus (PLRV) and Potato virus Y (PVY) are two important viruses causing serious potato yield losses in the North-east region and other planting areas in India. As a consequence, it is urgent to develop an efficient and quick method for the identification and diagnosis in the field. The results presented here showed that the reverse...

Solanum violaceum Ortega, (Indian nightshade), is a medicinal plant belonging to the family Solanaceae. It grows naturally as a weed in agricultural fields, forest edges, road sides and fallow lands throughout the North East Region of India. It is mostly consumed as a vegetable by the native people of the region because of its promising therapeutic...

An experiment was conducted in field during 2017-18 for efficiency evaluation of seven indigenous products along with a check (imidacloprid 17.8 SL at 20g a.i/ha) to manage Aphis craccivora Koch on cowpea. In the bio-efficacy study, leaf extract of Polygonum hydropiper at 5% was found to be most effective and efficient in aphid population reduction...

Potato affecting viruses is an important biotic factor that hampers both the quality and yield of potato production worldwide. The occurrence of potato viruses has been historically recorded in India. Viruses such as potato virus X (PVX), potato virus Y (PVY), potato virus A (PVA), potato virus M (PVM), potato virus S (PVS), potato leafroll virus (...

Being the most important mode of propagation of plants, disease-free seed is a basic requirement of progressive agriculture. However, many plant pathogens such as bacteria, fungi, virus, virus-like agents, nematodes, etc. are transmitted through seeds to the next generation. Seed transmission enables the earliest possible infection, which is a dete...

Alfalfa mosaic virus (AMV, family Bromoviridae, genus Alfamovirus) has an extensive host range. The reports of AMV available in India were dated far back as 1979 and 1981 found in alfalfa and brinjal crops respectively. In January 2019, field surveys were conducted for viral diseases infecting potato in Sonitpur and Jorhat districts of Assam state...

A study was conducted in vitro condition to analyse the morphology and efficacy of bio agent, plant extract and some chemical against P. mangiferae which was collected from different districts of Manipur. The morphological characters under study consist of colony and conidial characteristics such as colour, shape, size and appendages. The cultural...

Tomato is the most economically important fruit‐vegetable crop grown worldwide. However, viral diseases remain an important factor limiting its productivity with estimated quantitative and qualitative yield losses in tomato crop often reaching up to 100 per cent. Many viruses infecting tomato has been reported, while new viral disease have also eme...

Several isolates of Banana bunchy top virus (BBTV) have been reported worldwide. They are members of either the Pacific Indian Ocean (PIO) or the South East Asian (SEA) group. However, there is only one completely sequenced isolate published from the northeastern part of India till date. Therefore, we obtained the complete sequences of all the six...

The pumpkin leaf curl disease is an emerging disease of pumpkin in Assam, India. Symptomatic pumpkin leaf samples from different locations were immunologically tested using Begomovirus specific antibody. PCR with the ELISA-positive samples, using Geminivirus universal primers amplified 1.4 kb virus-specific fragments. Sequence of these amplicons sh...

The possible association of phytoplasmas with the Banana bunchy top virus (BBTV) and little leaf symptoms in banana was investigated. Symptomatology showed presence of characteristic little leaf symptoms in BBTV infected banana plants. Six banana samples showing little leaf were assayed for the presence of phytoplasmas and their association with BB...

An extensive survey was conducted during 2015-2017 in six North Eastern States of India covering 52 districts to record the incidence of sugarcane grassy shoot (SCGS) caused by phytoplasma and molecular characterization of the associated phytoplasma strains. The disease incidence was in the range 2-40%. PCR analysis using phytoplasma specific prime...

Cucumber mosaic virus (CMV) causes great losses in Bhut Jolokia pepper (Capsicum chinense Jacq.) plantations in Assam, India. To investigate possible means to induce plant resistance against this virus, the crude extract of bacterially-expressed double-stranded (ds) RNA, derived from CMV-2b gene (dsRNA_CMV-2b), was exogenously applied along with CM...

Bhut Jolokia (Capsicum chinense Jacq.) is a type of chilli extensively grown in North Eastern region of India, predominantly in the states of Assam, Nagaland and Manipur. Bhut Jolokia is recognized as the 7th hottest chilli in the world having a scoville heat unit of 1,041,427. Leaf curl virus disease of chilli is considered as the most serious dis...

Bhut Jolokia (Capsicum chinense Jacq.) is a type of chilli extensively grown in North Eastern region of India, predominantly in the states of Assam, Nagaland and Manipur. Bhut Jolokia is recognized as the 7th hottest chilli in the world having a scoville heat unit of 1,041,427. Leaf curl virus disease of chilli is considered as the most serious dis...

Computational biology or bioinformatics has its roots in the dawn of genomic revolution when research activities were started to sequence the genome of various organisms. Refinement in sequencing technologies and potential of genomic research resulted in meteoric growth of biological information such as sequences of DNA, RNA and protein requiring d...

Occurrence of severe mosaic disease of potato caused by Potato virus Y (PVY) in all the potato growing areas of Jorhat district of Assam, India was determined by DAS-ELISA. An integrated disease management experiment for severe mosaic disease was carried out at the Experimental farm of Assam Agricultural University, Jorhat in field condition compri...

Bhut Jolokia (Capsicum chinense Jacq.) is a type of chilli extensively grown in North Eastern region of India, predominantly in the states of Assam, Nagaland and Manipur. Bhut Jolokia is recognized as the 7 th hottest chilli in the world having a scoville heat unit of 1,041,427. Leaf curl virus disease of chilli is considered as the most serious di...

Citrus tristeza virus (CTV) is one of the biggest oppressions to the citrus industry globally and a major contributor of citrus decline. It is a phloem associated virus of various citrus species, containing positive-sense single stranded monopartite RNA genome with encapsidation by two different capsid proteins and transmitted by several aphid spec...

Incidence of Citrus tristeza virus (CTV) in commercially important citrus species; Khasi mandarin (Citrus reticulata), Assam lemon (Citrus limon) and rough lemon (Citrus jambhiri) in Assam, Meghalaya, Arunachal Pradesh and Nagaland of Northeast (NE) regions of India was studied using double antibody sandwich ELISA (DAS-ELISA) and reverse transcript...

Internal necrosis of carrot has been observed in UK carrots for at least 10 years, and has been anecdotally linked to virus infection. In the 2009 growing season some growers had up to 10% of yield with these symptoms. Traditional diagnostic methods are targeted towards specific pathogens. By using a metagenomic approach with high throughput sequen...

The diagnosis of novel unidentified viral plant diseases can be problematic, as the conventional methods such as real‐time PCR or ELISA may be too specific to a particular species or even strain of a virus, whilst alternatives such as electron microscopy (EM) or sap inoculation of indicator species do not usually give species level diagnosis. Next‐...

Resistance to rice virus diseases is an important requirement in many Southeast Asian rice breeding programs. Inheritance of resistance to rice tungro spherical virus (RTSV) in TW5, a near-isogenic line derived from Indonesian rice cultivar Utri Merah, was compared to that in TKM6, an Indian rice cultivar. Both TKM6 and Utri Merah are cultivars res...

An attempt was made to produce sensitive and specific polyclonal antisera against the viruses causing rice tungro disease, and to assess their potential for use in simple diagnostic tests. Using a multiple. sequential injection procedure, seven batches of polyclonal antisera against rice tungro bacilliform virus (RTBV) and rice tungro spherical vir...

Proceedings of the International Workshop on Tungro Disease Management, 9–11 November 1998, International Rice Research Institute