Farmers in three gewog of Shompangkha, Dekiling and Samtenling in Sarpang are losing chilli plants to a new disease, which is turning the plants yellow.
This is an addition to the common pests like mites, aphids and whitefly that hampers the growth and fruiting in chilli plants.
Officials from Agriculture Research and Development Centre (ARDC) in Samtenling say they observed the three pests in the dzongkhag for the last two years.
Principal horticulture officer, GS Rai (PhD) said the yellowing disease is new in the region. “We isolated the pathogen from the infected plant for the laboratory observation. We would be able to confirm the disease within 14 days,” he said.
He said that the centre does not have a technical facility for a molecular analysis after the culturing is completed. “We will observe that microscopically. Otherwise, there is no confirmatory facility here.”
The officials had visited 14 different fields in Shompangkha and observed at least one type of pest infection.
Farmers in Shompangkha said the pest damaged chilli plants when it was almost ready to harvest.
A farmer, Phurba Tamang, said the pest started to appear suddenly when the chilli plants were ready for harvest. “There was nothing I could do. The officials from the gewog told me to spray pesticides. I am using that now. I couldn’t harvest even a kilo of chilli.”
He said that a similar disease hampered chilli production last year.
The gewog mangmi, Ashman Rai, said the diseases were reported from nine households in the gewog. “As an immediate measure, pesticides were distributed to the farmers to prevent the spread.”
He said that it was important to solve the problem immediately before it spreads to other fields. “The harvest season is here. Stopping the disease here would benefit the people.”
Ashman Rai said that the gewog should stock pesticides to meet the immediate need of the people. “More people are into commercial farming today.”
However, officials from ARDC said spraying pesticides should be the last resort when it comes to containing the pest in plants.
This is to avoid the pest from developing resistance.
Officials said farmers might have to use stronger pesticides in the future to control such cases.
“We are doing a management trial to control the pest organically without using pesticides. It is not a guaranteed control measure and not as effective as the pesticides,” GS Rai said.
Senior plant protection officer, CM Dhimal, said the pest infection could also be because of climate change, seed, and poor field management. “The pest infections are different in different years. If the pest were the same as in the past, providing the farmers with prevention and management plans would be easy.”
He said that it would be difficult to come up with a concrete finding this season. “We are observing it now. By the time we come up with any management plans the season would be over.”
The official said the pesticides were imported into the country only once a year. The procurement is done based on past pest and disease incidents across the gewogs. “Farmers ask for the pesticides immediately but we cannot do that immediately.”
Farmers in Shompangkha said the pest infection was because the current chilli seedling was imported without proper evaluation and assessment.
A farmer, Nima Lama, said the weather and climate conditions of the plain would be different. “It would be difficult for hybrid plants to adapt to the conditions here.”
The officials from ARDC said that the best three-hybrid varieties of the chilli were distributed in 2017 to farmers after the chilli import ban was imposed in 2016.
GS Rai said it takes a minimum of three years to release a hybrid variety.
Officials say three hybrid varieties were introduced through fast-track evaluation with the multi-location trials conducted in different regions. “This could be the reason behind the current condition of the chilli plants.”
They also said it could be because of warm weathers.
GS Rai said the same disease and pest were also observed in the local variety. “The disease is not because of the imported hybrid. Phytophthora infection on peppers was seen in Bhutan since 1995. Only yellowing of plant is the new disease observed this year.”