The cyclonic storm ‘Dana’ made landfall in Odisha on the early morning of October 25, 2024 with high wind speed and heavy rainfall. In West Bengal, South and North 24 Parganas, Purba and Paschim Medinipur, Jhargram, Howrah, Hooghly, Kolkata and Bankura districts were mostly affected with heavy rain and flooding which affected kharif paddy in field before harvesting.
       
Among the rice insects, rice yellow stem borer (Scirpophaga incertulas) and rice leaf folder, (Cnaphalocrocis medinalis) are the dominant and most destructive insect-pest occurring throughout the country causing yield loss ranging from 10 to 60% (Chatterjee and Mondal, 2014; Chatterjee and Mondal, 2020). Among the insect-pests brown plant hopper (BPH), white back plant hopper (WBPH), plant hopper (PH), green leaf hopper (GLH), stem borer, leaf folder (LF) and whorl maggot (WM) in field condition are the important pests of West Bengal (Dana and Chatterjee, 2021). Over 90 per cent of the borer populations the yellow stem borer (YSB) [S. incertulas] is one of the major insects in kharif rice from seedling to maturity stage in new alluvial zone of West Bengal (Chatterjee et al., 2017; Chatterjee et al., 2020). The yield loss due to S. incertulas was estimated to be approximately 10-60 per cent in India (Panda et al., 1976; Pasalu, et al., 2005). Brown plant hoppers constitute one of the most important pests causing substantial yield losses (Konchada et al., 2017). Brown planthopper (BPH) [Nilaparvata lugens] and white backed plant hopper (WBPH) [Sogatella furcifera] have emerged as a major pest of rice in several Asian countries (Ramesh et al., 2014). These are the important sucking pests of rice and both adults and nymphs damage the phloem of rice plants and damage the plant directly by sucking on plant sap which may cause 25 to 75% loss (Kumar et al., 2022). Of the different insect pests attacking rice, BPH is an important sucking pest causing upto 100% yield losses (Anjali et al., 2024). Both adults and nymphs of brown plant hopper suck cell sap from paddy, congregate at the base of the plant just above the water level. The rice brown planthopper is a rice pest, which one is very harmful when the nitrogen fertilizer is applied at a higher rate (Singh et al., 2019). Affected plants leaves turn pale, yellow and later wither away leading to total drying of plant and if excessive attack occurs, the rice plants give a scorched appearance called ‘Hopper burn’ where circular patches of quick drying and lodging of matured plants are found. BPH may act as a vector of grassy stunt, ragged stunt and wilted stunt diseases. They secret honeydew at plant base exposing the plant to fungal and bacterial infections resulting “sooty mould”. Small sized hoppers are brown to grey in colour. A prominent white line is found in the neck region of WBPH.

The field roving survey was conducted by Rice Research Station, Government of West Bengal, Chinsurah, Hooghly during kharif 2024 at different villages of Singur block of Hooghly district. The survey was done on behalf of the all India coordinated research project on rice (AICRPR) of ICAR-Indian Institute of Rice Research, Rajendranagar, Hyderabad, Telangana State. The scientists of RRS, Chinsurah has visited for roving survey at Nasibpur (GPS Coordinates: 22^o48'N and 88^o16'E) and Antisara (GPS Coordinates: 22^o49'N and 88^o16'E) villages of Singur block during kharif 2024.
       
The farming community of Nasibpur and Antisara villages cultivated Jamuna, Swarna and Pratiksha rice varieties during kharif 2024. The soil was clay loam type. After harvesting of kharif rice, farmers normally used to cultivate boro paddy, potato, vegetables and mustard. The cultivation practices followed by the farmers are presented in Table 1. Planting was done randomly without maintaining any spacing but in some of the areas the rice plants were planted with very closer spacing which might be 15 cm x 15 cm or 15 cm x 10 cm. It was also informed by the farmers that in some areas, twice floods occurred in earlier of the season. The farmers applied fertilizers as IFFCO (10:26:26) @ 150 kg ha^-1 with urea @ 40-50 kg ha^-1 in their field; they also applied chlorantraniliprole 0.4% GR @ 11 kg ha^-1 or fipronil 0.3% GR @ 15 kg ha^-1 to manage insect-pests in their fields at around 30 days after transplanting (DAT). At the time of survey, the age of plants was 100-110 days i.e. they were very close to the maturity but, some fields were still full of moist and even in few places of the field, lower level of water stagnant was noticed.


       
The photographs of rice fields along with pest and their symptoms during survey conducted were recorded with and without GPS coordinates and placed in five plates.

A lot of insect-pests attack on kharif paddy were recorded during the survey in Singur block of Hooghly district in West Bengal. The pest infestation was very low except hopper because high rainfall during the cropping season and the cyclonic storm ‘Dana’ at the end of kharif season. The pest population and their incidence cannot be increased due to high level of rainfall.
       
The yellow stem borer attack causing white ear head, leaf folder, brown planthopper (BPH) and white backed planthopper (WBPH) attack were recorded (Table 2). The stem borer and leaf folder attack were below ETL. The ‘White ear head’ symptoms were recorded by the attack of stem borer. In Antisara village, rice was affected by hopper complex in vast areas and the typical hopper burn symptoms were appeared. The symptoms of attack by green leaf hopper (GLH) [Nephotettix virescens and N. nigropictus], another important rice hopper in all over World was not recorded. The GLH attack may show various symptoms on rice plants, such as stunted growth, yellowing and deformed leaves, increased tillering, or withering of plants. It was found that the Jamuna variety was most susceptible to hopper complex i.e., BPH and WBPH. Both the nymphs and adults of BPH and WBPH remain at the ground level and above the ground level, respectively and suck the plant sap. They are typical vascular feeder primarily sucking phloem sap leading to hopper burn. During the early infestation, sporadically in scattered way, the circular yellow patches appear which turn brownish soon due to the drying up of the plants. The patches of infestation by the hopper complex then may spread out and cover the entire rice field very quickly. The paddy grain setting is also affected severely. During sustained continuous feeding, they excrete a large amount of honeydews which attracts different fungus and bacteria.


       
The affected plants of the fields were completely dried up in ‘Hopper burn’ areas of the field. Irregular patches in some fields and in some areas the whole fields were affected and the ‘Hopper burn’ symptoms appeared. The rice plants became yellowish, brownish and straw coloured. Straws were brittle which were easily broken when lightly pressed by fingers. Plants were completely lodged in affected areas.
 
Why the infestation of YSB and RLF were low
 
The heavy rainfall along with high wind velocity during the cyclonic storm ‘Dana’, the adults of YSB and RLF were killed in rice fields as the soft bodied moths could not tolerate heavy rainfall and wind. Therefore, the laying of eggs by adult females were not done and the most destructive stages of the crop i.e., larvae of YSB and RLF could not emerge out to damage the crop. Farmers applied granules at 30 DAT to manage yellow stem borer and leaf folder and the applied chlorantraniliprole 0.4% GR found to be one of the best granules against YSB and RLF (Chatterjee et al., 2015).

Why symptoms of attack by GLH were not recorded
 
The important rice hopper, GLH population normally increases during October to November months. Other hopper, BPH and WBPH population increase just after the increased GLH population. The cyclonic storm ‘Dana’ with heavy rainfall and high wind killed the soft bodied leaf sucking insect, GLH which caused very poor population of GLH in the rice fields.
 
Why ‘Hopper burn’ symptoms were happened by hopper complex (BPH and WBPH)
 
The hopper population increased surprisingly for the favourable weather condition; due to high rainfall during the cyclonic storm ‘Dana’, water stagnation in the rice field just after completion of flowering of the crop favoured to create the congenial microclimate at the base of the plants for hopper complex and finally to multiply them to produce their progenies very quickly. Besides this, planting of susceptible rice variety (cv. Jamuna), the closer spacing, application of high doses of nitrogenous fertilizer, without application of any insecticide against hopper complex (sucking insect-pest), no pest survey and surveillance favoured hopper complex attack severely to the rice fields to generate ‘Hopper burn’ symptoms.
       
The photographs of ‘Hopper burn’ symptoms in rice fields with GPS coordinates (Plate 1). ‘Hopper burn’ symptoms along with stagnant water in rice fields (Plate 2). ‘Hopper burn’ symptoms in rice fields without GPS coordinates (Plate 3). RLF and white ear head symptoms in rice fields and adult YSB (Plate 4) and field survey in rice fields with GPS coordinates (Plate 5) have been presented with following five plates. It is clear from the plates that the BPH and WBPH have severely attacked rice plants during kharif season after the cyclone ‘Dana’ and clearly produced the ‘Hopper burn’ symptoms. The hoppers secreted honeydew at the base of the plant which exposed the plant to fungal and bacterial infections resulting grey to black coloured ‘sooty mould’. Sooty mould is a dark grey to black coloured fungus which grows on honeydew excreted by BPH and WBPH. Common genera of sooty mould fungi found are Aethaloderma spp., Capnodium spp., Scorias spp., Cladosporium spp., Euantennaria spp. and Trichomerium spp. etc. Framers were very much worried about the hopper attack in their rice fields and they would not harvest any rice from the severely affected fields. They wanted to know about the strategies to overcome the hopper attack in the next season. Therefore, the farmers were advised to follow the below-mentioned instructions from the next season to avoid hopper attack.



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Strategies to be undertaken to overcome ‘Hopper burn’
 
The farmers were advised to follow the below-mentioned scientific techniques for next onwards seasons to manage hopper complex and to devoid ‘Hopper burn’ in rice fields.

The hopper resistant rice varieties should be cultivated and Jamuna variety should be avoided.
       
The closer spacing (15 cm x 15 cm or 15 cm x 10 cm or 10 cm x 10 cm) should be avoided and transplanting should be done with proper spacing of 20 cm x 15 cm. The hopper susceptible varieties should be avoided and the resistant/ tolerant varieties should be grown in the next season.
       
During transplanting one row may be skipped after each of 8-10 rows.
       
Application of more ‘N’ fertilizer should be avoided in endemic areas as well as excess application of potassic fertilizer is encouraged which can help to tolerate/resist hoppers.
       
During the flowering period, the stagnant water may be drain out /pumping out from the rice fields, if possible.
Continuous field monitoring of randomly selected plants and survey are to be conducted diagonally in the field and chemical insecticides should be applied if the population of hoppers crosses economic threshold level (ETL).
       
The hopper predator, mirid bug may be released in the rice field.
       
The light trap @ 1 No./ha may be installed in the rice field.
       
The rice plants can be push aside at an interval of each of 8-10 rows after completion of flowering, if hopper attack starts.
       
Apply dust insecticides like malathion 2% D with dusters or spray any of the insecticides presented in Table 3, if ETL crossed.


       
For one ha area, 500 liters of water should be used and the nozzle mouth of the sprayer should be placed downwards towards the base of the plants.

The present study was supported by ICAR-Indian Institute of Rice Research, Rajendranagar, Hyderabad, Telangana State and Department of Agriculture, Government of West Bengal, Kolkata, West Bengal.
 
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The views and conclusions expressed in this article are solely by us, the authors and do not necessarily represent the views of their affiliated Institutions. We, the authors are responsible for the accuracy and completeness of the information provided, but do not accept any liability for any direct or indirect losses resulting from the use of this content.
 
Informed consent
 
All animal procedures for experiments were approved by the Committee of Experimental Animal care and handling techniques were approved by the University of Animal Care Committee.

We, the authors declare that there are no conflicts of interest regarding the publication of this article. No funding or sponsorship influenced the design of the study, data collection, analysis, decision to publish or preparation of the manuscript.