New Microbe Identified as Cause of Sesame Crop Disease in West Bengal

New Microbe Identified as Cause of Sesame Crop Disease in West Bengal

Researchers have recently identified a new microbe responsible for a peculiar disease that is affecting sesame fields in Midnapore, West Bengal. This discovery is crucial in understanding the disease’s impact on sesame crops and developing strategies to mitigate its effects.

Sesame: The Queen of Oil

Sesame, often referred to as the “Queen of Oil,” is one of the oldest oilseed crops, with evidence of its use dating back to the ancient cities of Harappa and Mohenjodaro. Sesame oil is known for its medicinal properties, containing antioxidants that are beneficial for heart health. However, despite its benefits, sesame oil is not commonly used as the primary cooking oil in India. The local varieties of sesame also require improvements to fully harness their potential benefits.

Prof. Gaurab Gangopadhyay’s Research

Prof. Gaurab Gangopadhyay from the Department of Biological Sciences at Bose Institute, an autonomous institute under the Department of Science and Technology, has been studying sesame for over 14 years. He and his team have successfully developed improved sesame varieties through molecular marker-assisted breeding. Their work has focused on enhancing the genetic traits of sesame to increase its agricultural productivity and health benefits.

Emergence of a Peculiar Disease in Sesame Crops

During their visits to sesame farms in the East and West Midnapore districts, Prof. Gangopadhyay and his team observed a strange disease affecting sesame crops. The disease appears after the plants reach the flowering and fruiting stages. Instead of continuing to flower, the plants regress to a vegetative state, and the flowers, which are typically white with pinkish tinges, turn green.

Identification of the Causative Microbe

Prof. Gangopadhyay began investigating the cause of this disease and discovered that it was linked to a new microbe residing in the gut of pests like leafhoppers and plant-hoppers, which are known as phloem suckers. The bacterium responsible for the disease is a cell wall-lacking Mollicutes, known as Candidatus Phytoplasma. These bacteria thrive in the nutrient-rich phloem and sieve cells of plants, causing them to malfunction.

Disease Transmission and Symptoms

The transmission of Phytoplasma occurs primarily through phloem-feeding insects such as leafhoppers, plant-hoppers, and psyllids. These pests are also known to infect other commercially important crops such as tobacco, maize, and grapevine. The disease caused by Phytoplasma in sesame results in disfigured and malformed floral parts, with a noticeable green, leafy appearance, a condition called virescence.

Exploring the Impact on Sesame Plants

Given the limited knowledge about Phytoplasma infestations, the research team conducted a detailed study to understand the impact of this bacterium on sesame’s metabolic pathways. The study, published in the Plant Molecular Biology Reporter in 2024, uses a multi-target approach to examine how Phytoplasma affects the plant’s molecular responses. This research could provide valuable insights into the disease mechanisms and help develop strategies to protect sesame crops from this harmful microbe.


Multiple-Choice Questions (MCQs):

  1. What is the name of the bacterium responsible for the disease affecting sesame plants in West Bengal?
    • A) Escherichia coli
    • B) Candidatus Phytoplasma
    • C) Staphylococcus aureus
    • D) Bacillus subtilis
    Answer: B) Candidatus Phytoplasma
  2. What is the primary method of transmission for Phytoplasma bacteria in sesame crops?
    • A) Airborne transmission
    • B) Through water droplets
    • C) Through phloem-feeding insects
    • D) Soil contamination
    Answer: C) Through phloem-feeding insects
  3. Which of the following crops is also affected by Phytoplasma infection, as mentioned in the article?
    • A) Wheat
    • B) Grape
    • C) Potato
    • D) Rice
    Answer: B) Grape
  4. What are the typical symptoms of Phytoplasma infection in sesame plants?
    • A) Wilting of leaves
    • B) Disfigurement and virescence of floral parts
    • C) Yellowing of stems
    • D) Increased growth rate
    Answer: B) Disfigurement and virescence of floral parts
  5. Who led the research team that identified the new microbe affecting sesame crops in Midnapore?
    • A) Prof. Amit Shah
    • B) Prof. Gaurab Gangopadhyay
    • C) Dr. Ramesh Kumar
    • D) Dr. Pravin Patel
    Answer: B) Prof. Gaurab Gangopadhyay