The Yogi Adityanath government has been informed about a growing crisis in guava orchards due to a severe nematode infection. The Central Institute of Subtropical Horticulture (CISH), through the chief secretary, has recently raised the alarm, and the government is contemplating action to protect the interests of guava orchardists.
Often referred to as the ‘apple of the poor’ for its nutritional value and affordability, guava is now facing a significant threat from this rapidly spreading infection, which arrived with foreign varieties like Thai Pink and Taiwan Pink. Currently, nearly half of the state’s guava orchards are believed to be affected.
According to a five-year survey conducted by the CISH, which operates under the Indian Institute of Agricultural Research (ICAR), nematode infection is a major crisis for guava crops.
The institute's Director, Dr T Damodaran, emphasised the seriousness of the situation, highlighting the negative impact on fruit quality, yield and the increased cost of production for orchardists.
While eliminating the nematode infection entirely is not possible, managing it to some extent has been found achievable, albeit with challenges. The use of fluopyram, a chemical treatment, has shown some success but is costly and offers only temporary relief, lasting around six months.
To combat the growing threat of nematode infestation in guava orchards, experts recommend treating the soil and roots of infected grafts with a 0.05% fluopyram solution, 15 days before transplanting them into the main field. Each graft should be planted as deeply as possible, with two litres of the fluopyram solution applied per plant for optimal results. Proper field selection is also crucial, as heavy soils can help suppress nematode activity.
This can be achieved through the continuous use of bio agents, such as ICAR’s Fusikont and bacterial bio-agents of the CISH. Additionally, scientists have identified rootstocks like Psidium cattleyanum and inter-specific Moley rootstock, which exhibit high tolerance to nematodes. Efforts are underway to rapidly multiply these rootstocks to aid in disease management.
Bio-control agents such as trichoderma harzianum, pocconia chlamydosporia, purpureocillium lilacinum and bacillus amyloliquefaciens have also proven effective in managing nematode infestations, although they require frequent reapplication. Incorporating nematode-resistant crops in intercropping and using organic products have shown moderate success in controlling the spread of the infestation.
Studies conducted by Dr PK Shukla, a pathologist at the CISH, have revealed that foreign guava varieties are highly susceptible to nematode infections, whereas traditional Indian varieties like Allahabad Safeda, along with indigenous varieties such as Dhawal, Lalit, Lalima and Shweta, show greater tolerance. To protect guava orchards from nematodes, farmers, gardeners and home growers are encouraged to plant these native varieties, which are also preserved and recommended by CISH.
Both the Central and state governments have presented varieties like Shweta and Lalit, ensuring that only authorised nurseries that have acquired the proper technology from the source institute are allowed to sell them. Authorities are urged to take strict action against nurseries and plant producers who sell these varieties illegally.
Additionally, CISH scientists, including Dr Prabhat Kumar, have developed a technology to prevent the spread of nematodes through planting material, further aiding in the protection of guava crops.
