Integrating biological pest management, drought resilience, and elephant deterrence for sustainable small scale cardamom production

Introduction

Cardamom, celebrated worldwide as the "queen of spices" for its distinctive aroma and flavor, originates from the moist tropical evergreen forests of India's Western Ghats a region also regarded as the centre of origin and diversity for black pepper. Commercial cardamom production faces several major constraints, including shoot and capsule borers, thrips, root grubs, whiteflies, nematodes, and a suite of diseases such as capsule and panicle rot, clump rot, Fusarium rot, leaf blight and various viral infections. The indiscriminate application of synthetic pesticides to control these pests and pathogens has led to elevated residue levels in export-oriented produce, prompting growing regulatory and consumer concerns. Consequently, the global reputation of this premium spice has been challenged. Meanwhile, demand for organic spices is expanding at roughly 20% per year (Krishnakumar, 2015) [8] . To re-establish India's leadership as the "spice bowl of the world" and supply safer products to international markets, a shift toward sustainable, higher-yield production is essential. This will require the adoption of good agricultural practices that emphasize eco-friendly pest and disease management, integrating physical, cultural, biological and botanical tools that conserve natural enemies and beneficial microorganisms, thereby restoring ecosystem balance in cardamom and black-pepper systems.

Materials and Methods

A two-year field trial was carried out on a 5-hectare small-scale cardamom farm in Idukki, Kerala, to assess the performance of a bio-intensive approach targeting pests, drought stress, and wild-elephant damage. Three integrated-pest-management (IPM) packages were designed and compared with an untreated control.

Assessment of different biological control agents for the management of pests in small cardamom

A field trial was carried out in a small-scale cardamom plantation near Idukki, Kerala, using a randomized block design (RBD). The layout comprised five treatments, each replicated three times. Bio-pesticide efficacy was assessed through seven spray applications on the cardamom plants. The initial spray was timed at the panicle-initiation stage, followed by four additional sprays at 20-day intervals. Details of the treatments, including the applied doses and application methods, are presented in Tables 1, 2 and 3. Three replications are followed for each module to evaluate under Randomized Block Design (RBD) (Pazhanisamy, 2015). The common practices which followed all the modules. 1. Stem and Capsule borer 2. Thrips

Root grub

The mean original data of percentage pod damage was calculated as percentage reduction over with the following formula (Abbott's 1925) Percent Reduction = (C -T) / C × 100

Drought mitigation management in small cardamom

The trials of the application of foliar sprays with PPFM and potassium silicates were conducted in small cardamom plantation.. The vast majority of these experiments were conducted in a randomized complete block design (RCBD) with at least three replications.

Assessment of Different Innovative Technologies for Deterring Crop Raiding Wild Elephants

To1-Solar-powered fences to protect fields from elephants,To2-Solar based Krishi Rakshak system is very effective in drivingoff the animals from the fields and keeping them away. The device automatically get switch on based on the system time or can be switched on manually using smart phone.,To3-Spray of Panchagavya based herbal extract of small cardamom plantation to keep the crop raiding wild elephant not entered in the field and To4-Place of Bee box to keep away the wild elephants in small cardamom plantation.

Results and Discussion

The average numbers of stem-borer, panicle-borer and capsule-borer larvae recorded for each treatment before and at various intervals after treatment are summarized in Table 1. Prior to spraying, the incidence of these borers ranged from 1.6 to 2.1 larvae per plant across the treatments. Following application of the microbial and botanical products, a statistically significant decline in larval populations was observed compared with the untreated control. The data ( [1] .

Conclusion

The study demonstrated that a combined preparation of Beauveria bassiana + Bacillus thuringiensis and B. thuringiensis var. kurstaki effectively suppressed stem, panicle and capsule borers while remaining harmless to the larval parasitoids Apanteles taragamae and Friona spp.; consequently, this mixture is suitable for incorporation into integrated pest-management programmes for small-scale cardamom. Methylotrophic bacteria are widely employed as bio-inoculants and are increasingly being considered as alternatives to synthetic fertilizers, offering eco-friendly, low-cost options that enhance plant growth and support sustainable agriculture. In the trial, the highest cardamom yield was 6.5 t ha⁻¹, representing a 32% increase over the control plot (3.8 t ha⁻¹). Economic analysis showed a net income of ₹ 790,000 ha⁻¹ for the treated plot versus ₹ 300,000 ha⁻¹ for the untreated plot, yielding benefit-cost ratios of 2.41 and 1.54, respectively. The bio-intensive pest-and disease-management strategies reduced pest and disease incidence and also helped mitigate drought stress.

Acknowledgement

AcknowledgementThe authors are grateful to the Director, ICAR-National Bureau of Agricultural Insect Resources, Bengaluru for providing the technical support of my research work. The authors are also thankful to Bio-micro Biotech for the financial assistance given to carry out the research work.

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