Rising temperature, prolonged rainless period due to climate change have created the perfect conditions in North India for large scale attack of pest and diseases in the tea plantations. Pest and diseases were present earlier, but it has aggravated over the last few years. In Northeast India, the incidence of this pest was initially limited to a few areas in the Dooars and south bank of Assam, but has been spreading rapidly in other tea-growing regions of Cachar, Tripura, Arunachal Pradesh, Darjeeling and Terai over the last two decades.
The major pests prevalent in North Indian tea plantations are tea mosquito bug (Helopeltis theivora) and Looper Caterpillar apart from Thrips. There has been growing incidence and spread of termite infestation in North India which is spreading to new areas. An approximate estimate of crop loss due to pest infestation in tea is as follows:
| Crop loss In South India per year | 15 million kg | |
| Crop loss In Northeast India per year | 132 million kg | |
| Crop loss in Indian tea per year | 147 million kg | |
| Revenue loss in South India | Rs.225 crores | |
| Revenue loss in North east India | Rs. 2640 crores | |
| Revenue loss in Indian tea per year | Rs. 2865 crores per year | |
The cost of plant protection in tea plantations in North India has increased manifold over the past two decades reaching to as high as Rs 25,000 to Rs 30,000 per hectares. This has had a negative impact on the viability of operations leading to lower exports and global competitiveness. The export volume of tea from North East decreased by 14% in 2022.
Indian tea industry uses pesticides which are approved by the Central Insecticides Board alongwith the guidelines issued by the Tea Board of India through it’s Plant Protection Code and Good Agricultural Practices listed by the Tea Research Association (TRA Tocklai) . Currently there are only seven pesticides which are approved for use in India by CIBRC, making it difficult for tea growers to effectively control tea mosquito bug and tea looper. The availability of narrow range of limited chemicals has led to resistance build up in pest populations. Additionally, there are restrictions on the use of pesticides in tea due to revision of MRLs in the EU, creating barriers to trade or processed teas from India to the EU.
TRA Tocklai recommends integrated pest management strategy for both pests which includes both chemical and non-chemical method. Plant Protection Scientists at TRA Tocklai have been evaluating several new molecules/ pesticides against the major pests through products available with the Indian pesticides manufacturers and have submitted bio efficacy and residue studies through the manufacturers to the Central Insecticide Board and Registration Committee (CIB&RC) . The list of promising pesticides and few other formulations which are found to be effective in controlling the major pests are given below in the table :
| Pest mane | Existing PPC cleared pesticides | New pesticides available in Indian market and approved by CIB&RC for other crops. (efficacy > 70-80%) |
| Tea mosquito Bug | Thiamethoxam 25% WGThiacloprid 240SC (21.7% w/w)Clothianidin 50 WDG | Sivanto 200 ® (Flupyradifurone 200 w/v): Bayer Crop Science LtdSolomon ® (Beta-cyfluthrin 90GL +Imidacloprid 210G/L OD): Bayer Crop Science LtdToken ® (Dinotefuran 20 %SG): Indofil Industries limited.D ONE ® (Sulfoxaflor 50%WG): Dhanuka Agritech LtdRogor/ Tafgor ® (Dimethoate 30 EC) FMC Corporation/ Rallis India Limited |
| Tea Looper | Emamectin Benzoate 5% SG Flubendiamide 20 WG | Vayego ® (Tetraniliprole 120 G/L+ Spirotetramat 240 G/L SC): Bayer Crop Science LtdEvicent® 45 WG (Emamectin benzoate 5%+ Lufenuron 40% WG): Syngenta India Ltd.Sumitomo Sumipleo® (Pyridalyl 10% EC): Sumitomo chemical Ind. Ltd. |
Since these pesticides do not have a label claim for use in tea, growers are unable to use these pesticides though they are approved by CIB&RC and widely used in other crops in India for the control of different sucking pests. Considering the huge crop loss due to Tea Mosquito Bug and other major pests, the Tea Research Association (TRA) which is a public authority under Department of Commerce has requested the Secretary, Agriculture Government of India to kindly intervene for allowing provisional approval under National exigency of the above-mentioned pesticides for 2 years for the benefit of the tea growers in India. As per norms followed by the Government of India, any public authority or Government body can request provisional use of compounds up to a maximum of 2 years.
