Chilli black thrips outbreak: supporting Indian farmers to protect crops sustainably

Date:12-05-2024

Outbreaks of Thrips parvispinus, commonly known as chilli black thrips or Southeast Asian thrips, are causing challenges for smallholder farmers in India. These tiny, dark-coloured invasive pests are responsible for considerable economic losses, particularly for growers who rely on chilli crops as a primary source of income. Chilli black thrips are notorious for their aggressive feeding habits and rapid reproduction, leading to widespread crop damage and jeopardizing livelihoods across India.

Overview of chilli black thrips

Chill black thrips are small, slender insects, typically measuring 1-2 millimetres. Though diminutive, they are highly destructive. The adult thrips mostly gather on flowers and the undersides of leaves, while the nymphs stay only on the undersides. Both adults and young nymphs harm plants by scraping and sucking the sap. Infestations can slow plant growth, cause flowers to fall off, and reduce the development of fruits. This can lead to lower crop yields. As well as affecting chilli crops, black thrips threaten capsicum, eggplant, and certain ornamental plants, making them a particularly challenging pest to manage.

Chilli black thrips on a chilli flower. Image by UASR

Chilli black thrips spread and impact in India

Over the last decade, chilli black thrips have spread rapidly across India. Farmers first reported the pest on Papaya in 2015, and then, in 2021, severe damage was reported to chilli crops in Andhra Pradesh. Southern states like Andhra Pradesh, Karnataka, and Tamil Nadu, where chilli farming is a significant agricultural activity, have been hit particularly hard. Changes in climatic conditions have exacerbated the spread of these pests, with warmer temperatures and increased humidity providing ideal conditions for their reproduction and spread.

Chilli is not only a staple in Indian diets but also a significant export product, making it central to many rural economies. As such, the impact has been devastating for smallholder farmers, who often lack access to resources and information to combat such infestations effectively and sustainably.

Management challenges

One of the primary challenges in managing chilli black thrips is their rapid life cycle and high reproductive rate. This can make traditional pest management practices ineffective. Chemical control methods, while widely used, have proven to be only temporarily effective. The indiscriminate use of pesticides can lead to resistance among thrips populations.

Integrated Pest Management (IPM) strategies are essential in combating chilli black thrips. IPM combines biological controls, cultural practices, mechanical practices, and the judicious use of chemical treatments when deemed appropriate. However, implementing such strategies requires an understanding of IPM principles and resources and support from agricultural extension services.

As such, addressing the thrips outbreak requires a coordinated approach among farmers, researchers, and government bodies. From October to December 2024, PlantwisePlus and its partners are conducting a communication campaign to help farmers combat the threat of Thrips parvispinus, focusing on Karnataka, Andhra Pradesh, and Tamil Nadu. This campaign is leveraging partnerships with local organizations in each state that have strong networks among farmers, enabling broad and effective outreach.

Regional partners

Each partner organization will play a vital role in implementing the campaign at the grassroots level. The partners in each region are:

Tamil Nadu: M S Swaminathan Research Foundation

Karnataka: Institute of Agricultural Technologists

Andhra Pradesh: EFFORT

PlantwisePlus has developed a Pest Management Decision Guide (PMDG) in collaboration with national institutes (NBAIR, IIHR), State Agriculture Universities (ANGRAU, PJTSAU, UASB, UASR, TNAU, AAU) and other government and non-governmental partners, to aid in identifying and safely managing chilli black thrips. This guide provides practical advice on identification, monitoring, control methods, and the use of biopesticides as safer alternatives to conventional pesticides, which can mitigate health and environmental risks. The PMDG is available in regional languages, ensuring accessibility and understanding for farmers in each area.

The campaign also highlights how the CABI digital tools can support advisors and farmers in identifying and managing chilli black thrips.

1. Bioprotection Portal – Provides information on locally available biopesticides that can help manage Thrips parvispinus effectively.

2. Crop Sprayer App – Assists farmers in accurately calibrating their pesticide and biopesticide sprayers to optimize plant protection product application.

3. PlantwisePlus Knowledge Bank and PlantwisePus Factsheets app – These tools allow farmers to access comprehensive pest management information and visual aids for identification, including the new Pest Management Decision Guide.

The campaign aims to reach at least 6,000 farmers with information on how to tackle thrips sustainably.

Kritika Khanna leading a workshop on chilli black thrips in Tamil Nadu

Working with partners to manage thrips

So far, CABI has conducted workshops with partners in Tamil Nadu, Karnataka and Andhra Pradesh. Attendees included extension workers, students, women farmers, farmer producer organizations and agro-dealers. The training workshops covered effective strategies for managing these invasive thrips and showcased how the PlantwisePlus digital tools can support early identification and better pest management practices.

Through these joint efforts, CABI and its partners aim to reduce the impact of chilli black thrips by sharing knowledge and resources on sustainable options for managing this invasive pest.