# NIPGR scientists find a calcium channel that spreads a plant's alarm against insect attack

URL: https://upsc.help/current-affairs/2026-11-01/cngc13-plant-calcium-alarm-nipgr/
Date: 1 November 2026 (2026-11-01)
Source: The Hindu, Page 13
UPSC papers: GS3
Publisher: upsc.help (Pratidin), free and open-source UPSC Civil Services current affairs. Not affiliated with UPSC. Every fact was checked against the source reports by a separate review before publishing.

**In one line:** NIPGR researchers showed that the calcium channel CNGC13 carries a plant's alarm from an insect-damaged leaf to its other leaves, switching on their defences.

Scientists at the National Institute of Plant Genome Research (NIPGR), New Delhi, have identified a calcium channel that helps a plant pass an alarm from a leaf being eaten by insects to its undamaged leaves. The protein, CYCLIC NUCLEOTIDE GATED CHANNEL13 (CNGC13), lets calcium ions flow into cells. The study, from the laboratory of Jyothilakshmi Vadassery with Misha Kumari as lead researcher, was published in the Proceedings of the National Academy of Sciences (PNAS) in 2026 under the title "The Ca2+ channel CYCLIC NUCLEOTIDE GATED CHANNEL13 regulates vasculature-mediated systemic Ca2+ and jasmonate signaling on herbivory". The team worked with Arabidopsis thaliana, a small mustard-family weed used as a model plant, and the tobacco cutworm Spodoptera litura, a caterpillar pest that feeds on many crops.

CNGC13 was strongly switched on by wounding and insect feeding and is found in the plant's vascular tissue, its system of veins. In mutant plants lacking it, the calcium signal reaching distant leaves was weaker and delayed, the defence hormone jasmonic acid built up less in those leaves, and defence compounds called glucosinolates were not mobilised properly. Caterpillars feeding on these mutants gained more weight, showing the plants were less protected. Plants that lacked both CNGC13 and CNGC19, a calcium channel earlier linked to defence against Spodoptera, were the most vulnerable. Glutamate receptor-like channels (GLRs) were already known to relay such long-distance alarms; the authors' preprint describes CNGC13 as working in a parallel branch, which suggests plants use more than one channel type to carry the signal.

Plants cannot run from attackers, so they rely on fast internal signals: calcium waves, electrical and hydraulic signals and reactive oxygen species travel from the wound and prime distant tissues to raise chemical defences. Knowing which proteins carry these signals gives breeders and genetic engineers targets for crops with stronger natural pest resistance, and the researchers suggest this could support more sustainable approaches to pest management. The work is basic research on a model plant; whether the same channel works the same way in crops such as mustard, cotton or soybean, and whether boosting it carries costs for growth, are open questions for further study.

## Prelims facts

- NIPGR, New Delhi, identified CNGC13, a calcium channel that relays the alarm from an insect-damaged leaf to undamaged leaves; the work appeared in PNAS in 2026.
- CNGC13 is induced by wounding and insect feeding and is located in the plant's vascular tissue.
- Without CNGC13, Arabidopsis plants showed weaker systemic calcium and jasmonic acid signals, and Spodoptera litura larvae feeding on them gained more weight.
- The finding adds a second route alongside glutamate receptor-like channels (GLRs) for long-distance defence signalling in plants.
- Such signalling proteins are potential targets for breeding or engineering crops with stronger natural pest resistance.

## Quick recall

- **Which institute identified CNGC13's role in plant alarm signalling?** National Institute of Plant Genome Research (NIPGR), New Delhi.
- **In which journal was the CNGC13 study published?** Proceedings of the National Academy of Sciences (PNAS), 2026.
- **What kind of protein is CNGC13?** A cyclic nucleotide gated channel that lets calcium ions into cells.
- **Where in the plant is CNGC13 located?** In the vascular tissue (the veins).
- **Which insect was used in the CNGC13 study?** Spodoptera litura, the tobacco cutworm.
- **Which defence hormone built up less in distant leaves of cngc13 mutants?** Jasmonic acid.
- **Which channel family was already known to relay long-distance wound signals?** Glutamate receptor-like channels (GLRs).
- **Which plant family does Arabidopsis thaliana belong to?** The mustard family (Brassicaceae).

## Prelims practice question

CNGC13, recently identified by Indian scientists in the context of plant defence, is best described as:

(a) a bacterial toxin gene used in insect-resistant crops
(b) a calcium channel that helps relay alarm signals to undamaged leaves
(c) a pheromone used in insect traps
(d) an enzyme that synthesises chlorophyll

Answer: (b) a calcium channel that helps relay alarm signals to undamaged leaves. CNGC13 (cyclic nucleotide gated channel 13) is a calcium-permeable channel in the plant's vascular tissue. NIPGR scientists showed it carries systemic calcium and jasmonate signals after insect attack. Bacterial toxin genes such as cry genes from Bacillus thuringiensis are a different technology.

## UPSC previous-year questions this connects to

- UPSC Mains 2019, GS3: How can biotechnology help to improve the living standards of farmers? (https://upsc.help/pyq/gs3/#q360)
  How to use this story in the answer: Use the CNGC13 finding as an Indian example of basic research that could lead to pest-resistant crops and lower input costs for farmers.
- UPSC Mains 2025, GS3: How can India achieve energy independence through clean technology by 2047? How can biotechnology play a crucial role in this endeavour? (https://upsc.help/pyq/q063-can-india-achieve-energy-independence-through-clean/)

## Mains practice question

Understanding how plants signal and respond to insect attack can open new routes to sustainable pest management. Discuss with reference to recent Indian research. (150 words)

### Model answer

In 2026 scientists at NIPGR, New Delhi, reported in PNAS that the calcium channel CNGC13 relays a plant's alarm from an insect-damaged leaf to undamaged leaves.

## What the research shows
- CNGC13 is induced by wounding and Spodoptera litura feeding and sits in vascular tissue.
- Mutants lacking it had weaker systemic calcium and jasmonic acid signals; caterpillars gained more weight on them.
- It works alongside glutamate receptor-like channels, so plants use multiple alarm routes.

## Routes to sustainable pest management
- Breeding or gene editing to strengthen natural defence signalling.
- Priming defences instead of blanket pesticide spraying, fitting integrated pest management.
- Less pesticide use reduces residues, resistance in pests and harm to pollinators.

## Caveats
- Findings are in a model plant; crop validation is needed.
- Stronger defences may reduce growth or yield.
- Regulatory clarity for gene-edited crops matters.

Basic plant science like this is the foundation for the next generation of pest-resistant crops.

## The basics

## Why this matters
Plants lose a large part of their yield to insects, and farmers respond with pesticides that leave residues, kill pollinators and breed resistance. A different approach is to understand and strengthen the plant's own defences. The NIPGR finding on CNGC13 is a small but real step in that direction, and it touches several examinable ideas: cell signalling, plant hormones, model organisms and integrated pest management.

## How a plant raises the alarm
A chewing insect damages cells. Damaged cells release signals, and within seconds to minutes calcium levels rise inside cells near the wound. The signal then travels, mostly through the veins, to distant leaves, which start making defence hormones and chemicals before the insect reaches them.

## Why calcium?
Cells keep calcium inside their main fluid at very low levels and pump it out constantly. That makes a sudden rise easy to detect, so calcium works as a switch. Proteins such as calmodulin read the rise and turn on genes. See Calcium signalling in plant cells.

## What the experiment showed
The team compared normal Arabidopsis with mutants lacking CNGC13. See Arabidopsis thaliana as a model plant for why this weed is used. The hormone involved is explained in Jasmonic acid and plant defence.

## From lab to field
The practical goal is crops that defend themselves better, used within Integrated pest management so that chemical sprays become a last resort. That will need testing in crops and careful checks for any cost to yield.

## Sources

- https://biopatrika.com/academia/researcher-spotlight/cngc13-systemic-calcium-signaling-plant-defense/
- https://www.biorxiv.org/content/10.1101/2025.06.16.660006.full.pdf
- https://superkalam.com/current-affairs/01-11-2026/indian-scientists-find-new-gateway-in-plants-alarm-system-pg13-a967aafb-e7a8-4b82-a5a2-01be5b4b051e
- https://pherobase.com/literature/data/details/B/19634