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Indigenous technical knowledge (ITK) based botanicals for rice pest management in eastern India: An overview

Mayabini Jena and Totan Adak

ICAR-National Rice Research Institute, Cuttack, India-753006

 

Protection of rice crop from insect pests and diseases is prime need to sustain food security. A study carried out by Rockfeller foundation revealed that seven out of 20 major challenges in rice production are insect pest and diseases (Herdt, 1991). Among the biotic stresses insect pests caused about 10-15% yield losses. The average yield losses in rice had been estimated to vary between 21-51 per cent. Although agricultural chemicals stand as “Miracle Weapons” in the front line of defense, rice plants are not free of problems. Despite their popularity, serious concerns have been raised about their health risks to human and non-target toxicity.

Eco-friendly approach for rice insect pest management without compromising with the productivity, has placed plant based pesticides or botanicals at a high priority area in the present pest management scenario. Rice, being the major food crop of India and it’s delicacy as scented rice and organic rice, attracts more attention for safe pest management strategy. The indigenous technical knowledge (ITK), existing in the rural and tribal areas of India, helps in identifying different botanicals which possess the potency to manage the array of pests effectively. Botanical pesticides are the important alternatives to minimize or replace the use of synthetic pesticides as they possess an array of properties including toxicity to the pest, repellence, anti-feedance, insect growth regulatory activities against pests of agricultural importance. Moreover they are safe to use, easily available and cost effective. Most of them have medicinal properties which can keep the environment safe.

Indigenous technical knowledges (ITKs) are knowledge based techniques used from time immemorial or from old days by a community of people. Generation after generation, the technique went on utilized and also simultaneously was refined to be better and better through continuous use. In India, pest management and botanicals are very keenly related because the country possesses a very rich diversity of flora. Many botanicals are being used as ITK for pest management in different crops. Among diverse crops, rice occupies the major place in terms of its cultivation, consumption and the role it plays in the country’s food security, economy and social up-gradation. Rice occupies largest crop growing area equal to about 43.5 m ha during 2014-15 (Source: Directorate of Economics & Statistics, D&ES). Obviously, more production technologies were evolved related to rice which consists more of knowledge based protection techniques.

          The eastern India, consisting of about 60% of the total rice growing area of the country (26.8 mha), possesses about 70% of the rainfed area including about 40% of the unfavourable low lying area. These areas are always prone to erratic weather conditions like deficit or surplus rainfall, delayed monsoon or prolonged rain and cyclone upto harvest leading to unpredicted yield loss or gain. As the risks are many, farmers always are reluctant to invest more towards different agricultural inputs and look towards the low cost technologies but with high impact. In addition, this part of the country harbours about 55% of the total tribal population among which the Santals, Oraon, Munda, Gond, Bhumij, Ho are dominant and are settled agriculturists. Rice is their only food as it serves them in the form of breakfast (Pressed rice, puffed rice, rice cake and pitha), lunch and dinner (Cooked hot rice called bhata and water rice known as pakhala), delicacy as sweet rice ‘khiri’ and rice liquor ‘handia’. So, they grow rice as major cereal and confront the pests that attack their rice crop with indigenous technologies. They also need low cost protection technologies as they are not acquainted with the present day pesticides and application technologies.

If we assess the pest situation of eastern India, we should be well aware of the ecologies that exist in this part. The upland ecology consisted of about 16% area whereas irrigated area is only 21%. Shallow lowland ecology is mostly favourable and more or less resembles irrigated ecology under normal monsoon and rainfall. It is comprised of 39% of the area. The rest of the area are under unfavorable lowland, i.e., semi deep, deep and very deep low land ecology, occupying rest 24% of the rice area (Mohapatra, 2014). The upland rice is mainly infested with termites and gundhi bug, whereas, ants and grass hoppers are of minor occurrence. Diseases like blast and brown spot are more prevalent. The irrigated or favourable rainfed lowland ecology harbours almost all insect pests and diseases. But, it also provides the scope for implementing proper control methods due to its favourable water level.  The unfavourable low land ecology has the minimum pest situation which is also difficult to control due to increasing water level during wet season. The shift of a particular pest to later months also occurs depending upon weather condition so that it becomes difficult to predict pest attack and also to pre-schedule the management strategy.

          The eastern India is having the largest share of tribal area in the country. About 37% tribal population of eastern India have their own land of cultivation and their major occupation is rice cultivation. They grow more traditional rice varieties. They use less or no chemical fertilizers. They do not use chemical pesticides in actual sense of using. (Cypermethrin based pesticides entering to the system but misused). They use ITK-based protection methods for management of insect pests and diseases. Productivity levels with reference to crop yields across the tribal dominated states over a ten year period (2003-04 to 2012-13) shows that average food grain yield in the tribal dominant states is relatively less compared to the all India average. But case study conducted during 2007-2011 (DST, TSP project) revealed that the low yield was mainly due to low yielding traditional varieties and lack of knowledge to select varieties according to ecosystem.

        Several ITKs are being used for pest management encompassing their skills, experiences and insights for rice and other agricultural production. The ITKs used for pest management are basically plant-based. Some are already used for rice pest management. Some others, which are used in areas other than rice, can find a place in protection of rice crop. The understanding of farmers’ of its concepts is the key to its success. Many plants were reported to have a role in plant protection as per the existing ITKs in eastern India. However, rice being the major food crop, most of them are being used in rice pest management in different places.

Reported plants used as ITK in rice:

 

Sl No

Plant

Scientific Name

State

1.      

Neem cake

 Azadirachta indica

Odisha

2.      

Karanja  cake

Pongamia pinnata

Odisha

3.      

Parasi  leaves

Cleistanthus collinus

Odisha, WB, Jharkhand

4.      

Wild sugarcane  shoot

Saccharum  spontaneum

Odisha

5.      

Mahula flowers

Madhuca indica

Odisha

6.      

Sal flowers

Psorea robusta

Odisha

7.      

Tobacco leaves 

Nicotiana tobacum

Odisha, Jharkhand, Assam

8.      

Harida fruit (raw)

Terminalia chubula

Odisha

9.      

Begunia leaves

Vitex nigundo

Odisha, Jharkhand

10.                         

Custard Apple leaves and seeds

Annona squamosa

Jharkhand

11.                         

Bamboo tender shoots

Bambusa sp

Odisha

12.                         

Keturi Halodhi or wild turmeric

Curcuma aromatica

Assam

13.                         

Peel of Robab tenga

Citrus grandis

Assam

14.                         

Kubabool fruits

Acacia spp

Odisha

15.                         

Kalothia plant

Tephrosia purpurea

Odisha

16.                         

Cashewnut-shell oil

Anacardium occidentale

Odisha

17.                         

Water pepper leaves

Polygonum hydropiper

Odisha

18.                         

Keond/kendu/tendu tree

Diospyros melanoxylon

Jharkhand

 

19.                         

Bael leaf and branch

Aegle marmelos

Jharkhand

20.                         

Jack fruit

Artocarpus heterocephyllus

Assam

21.                         

Datura

Datura stramonium

Odisha

22.                         

Ber branch

Ziziphus jujuba

Assam

23.                         

Curry leaves

Murraya koenigii

Assam

24.                         

Finger millet heads

Eleusine coracana

Bihar

25.                         

Kochila  leaves for weed management

Strychnus nuxvomica

Odisha

26.                         

Arakha leaves

Calotropis gigantea

Odisha, Jharkhand

(Source: Jena M, 2012)

       

Besides these plants, many other ITKs exist in eastern India comprising of different methods, non-botanical interventions, ecological, cultural, varietal particulars and processes which add/ can add to the pest management system of rice.

 

Efficacy of ITKs

But the question arises – In the present day situation, what is the need of ITKs? Are the farmers still using ITKs for pest management in rice? Is it possible to implement ITK-based botanicals in the rice growing areas?

If we analyse the relevance of botanical based ITK, chemical insecticides still dominate the plant protection system of rice even after the hazardous effect felt during late sixties just after green revolution. Though steps has been taken to develop less toxic and less persistent products like synthetic pyrethroids and organophosphates or pesticides with novel mode of action, pollution still exists in soil, water, different cereals and other grassy plants. The residue affected the entire food chain thereby contaminating human beings and causing serious health hazards.  Beneficial organisms in rice ecosystem, particularly the predators and parasites of rice insect pests, were destroyed by chemical insecticides. Due to prolonged use of  these chemicals, insects has developed tolerance to many pesticides, gradually necessitating frequent increase in dose which further added to the environmental pollution.

ITK based botanicals can become an integral part of pest management in rice because they are indigenous, hence easily available. Their potentiality is well known from time immemorial. They degrade within very short period, hence environmental friendly. The ITKs existing in the country are based on their local availability at low or no cost. The botanicals from such ITKs, namely- neem, karanja, kochila, water pepper, wild sugarcane and parasi were collected and validated in farmers’ field condition and also in the controlled as well as field conditions of National (Former Central) Rice Research Institute, Cuttack  and were found to  be effective. As most of the botanicals are being used for medicinal purpose, social acceptance is more.

 

Use of ITKs in rice Integrated Pest Management (IPM):

          Use of botanical pesticides is an important component in the integrated insect pest management (IPM) system of rice. They are natural pesticides and are found to be compatible in the IPM programmes. According to the incidence of insect pests in different rice ecosystems, use of botanicals can be planned for successful management of both insects and diseases. Particularly, unfavorable low land rice ecosystem, which does not provide much scope of using pesticides, ITKs can be the only option for pest management.

 

Precautionary measures for popularizing the use of botanicals:

·     Appropriate time of application as well as exact dose of botanicals play an important role in controlling a particular insect pest.

·     Mode of application and also the application of perfect formulations are equally important to get better results.

·     Preparation of botanical formulations with farmer’s participation can make the application easier and effective.

·     Community approach for botanical based pest management system through large scale plantation of pesticidal potential plants can be able to provide a safe and cost effective strategy to rice farmers of the country.

·     Areas already having the source of botanicals make the botanical based integrated pest management system convenient to adopt.

·     Demonstration of the efficacy of botanicals through field trials in farmer’s field makes the methods more popular and viable.

·     Large scale plantation of botanicals through farmer’s participation.

 

Key issues related to botanical based pest management:

In spite of their efficacy and eco-friendly nature, botanicals have not reached farmers’ field as commonly as chemical insecticides. They may become popular by -

·     Integration of more botanicals to the system as with the diverse rice ecosystem of the country, only one botanical will not be able to cater the need of the farmers. It requires more botanicals to be in hand with efficacy for different pests occurring in different ecological conditions.

·     Development of standardized bioassay system to screen the efficacy of different plants.

·     Selection of proper target area and target farmers whose need for botanical use in rice is urgent.

·     Development of farmers’ friendly approach with simple formulation technology for ready-to-use botanical preparation at local level.

·     In the case of botanicals causing phytotoxicity, dosage-response relationship need to be worked out carefully.

·     Large scale plantation of Neem, Karanja and other plants are to be encouraged so that obtaining botanical pesticide will be easy.

·     Safety of new botanical pesticides is to be worked out.  

·     Policy decision for popularization of botanical application.

 

Conclusion:

Botanicals have proved their potency to control the complex insect pest situation of rice. The past experiences and present efforts will certainly enable us to identify and use effective, economic and environmentally acceptable plant products for successful management of insect pests in rice.        

 


Source: OUAT Souvenir