Overview
- The importance of chilli in India
- The problem of Chilli Black Thrips
- Regions most heavily affected by the outbreak
- Invasive thrips outcompetes native species
- Control measures for thrips on chilli
The importance of chilli in India
India is the worldwide leader in the production, consumption, and export of chilli (Capsicum annuum) (ANGRAU, 2022). Indian chilli is famous for its intense flavour and colour. It accounts for 42% of all spices that are exported by the country.
The state of Andhra Pradesh is the largest chilli producer, followed by Telangana, Madhya Pradesh, Karnataka, and West Bengal. The Guntur Chilli Yard in Andhra Pradesh is Asia’s largest chilli market, which influences domestic and international prices.
The problem of Thrips parvispinus
In 2021 a new thrips species was found to severely damage the chilli crop in Andra Pradesh. It was identified as Thrips parvispinus, commonly called, “Chilli Black Thrips (CBT)”. It has since expanded to other states in southern India. CBT is a lacerating insect that originates from Southeast Asia. First reported in India in 2015 on Papaya, these insects lacerate the tender leaves and flowers before consuming the tissues . Lacerations, especially of the flower, impair fruit formation. Concerningly, CBT is polyphagous, i.e., it can feed on different plant species. In addition to chilli, it damages crops such as cotton, bell pepper, red and black grams, mango, watermelon, and others.
Regions most heavily affected by the outbreak
During 2022, CBT significantly damaged the chilli crop in six southern states (see map). The estimated losses in severely affected areas ranged from 85 to 100% . Its unexpected occurrence and high severity of damage left farmers with no choice but to apply chemical pesticides to protect their crops. This turned out to be a costly and fruitless exercise. Additionally, chilli damaged by the CBT fetched lower prices in the market, which pushed many farmers to the brink.
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Invasive thrips outcompetes native species
Prior to the infestation by CBT, Chilli Thrips (CT), Scirtothrips dorsalis, was the dominant pest in southern India. However, multiple studies have shown that CBT has dominated CT during the last two years. It is unclear whether CBT has emerged due to climate change, lack of competition from other pests, lack of natural enemies, indiscriminate use of pesticides, or from a combination of these factors. Field observations and anecdotal reports suggest that several chemical molecules are ineffective in managing the CBT populations.
Thrips are generally understood to thrive when the conditions are hot and dry. However, CBT appears to thrive even when the conditions are hot and humid. This was observed during 2022, when a few districts in Telangana received 40% more rainfall in the months of September, October and November, which coincides with the cultivation of the chilli crop.
Control measures for thrips on chilli
The Union Agriculture Minister is calling for a shift towards Integrated Pest Management (IPM) strategies, in place of chemical pesticide application, to manage CBT. IPM measures for thrips include pre-emptive pest surveying, cultural practices, and, notably, increasing farmers’ access to biopesticides and biocontrol agents.
The CABI BioProtection Portal is keen to support this call with a repertoire of biological products for managing thrips in India. The products listed on the Portal include fungal microbials like Beauveria bassiana (Abtec Beauveria) and Lecanicillium lecanii (Biosar).
- Not sure where to start with fungal microbials? Learn more in our beginner’s guide!
- To find out more about the main pests and diseases affecting chillies and how to control them, read COLEAD’s “Guide to good crop protection practices for chillies and sweet peppers” (available in English and French).
