Dr. Kumaravadivelu and Mr. U. Gopala Krishna
A resourceful and beautiful plantation area is situated in Shevaroy hills in an area of about 385 square miles in Salem district of Tamilnadu, South India. Shevaroys is hosting 67 villages with a total population of about 40,000 out of which 15,000 are tribals, taking up traditional agriculture; the system along with a good amount of livestocks is compact with its own natural balance acting as a model ECOFRIENDLY HORTICULTURE ZONE.
Elevation of Shevaroys ranges from 2500 to 5200 feet above MSL, mean temperatures ranges from 22 to 25 degree Celsius. Winter temperature may rarely go below 10 degree Celsius and on hottest day the temperature may shoot up to 32 degree Celsius. The average rainfall is about 45" to 60" is predominantly from North East monsoon with the distribution of 17% as summer showers (MarchApril), 37 to 47% during South West monsoon (June to· August) and the rest of 40 to 46% during North East monsoon (October to December).
Shevaroys Plantations
Plantation production systems In Shevaroys involve the use of fertilizers to supply plant nutrients; inorganic and organic amendments to improve the soil quality; and weedicides/pesticides to control weeds, insects and other pests. These practices are very important in plantation production and management. However, the mismanagement or excessive use of chemical fertilizers and pesticides, which is characteristic of hi-inputs modem farming, creates soil fertility problems, environmental pollution and degradation of surface/ground water. Problems associated with the quality and quantity of plantation produces due to this impact and damages on health of human, livestock and wild life are inevitable.
In other words, adding large doses of inorganic chemicals in modern plantation system without the use of organic, is always danger to soil health by way of humus depletion and fall in plantation production. Hence there is a strong need for undertaking agricultural activities which is safe to plantation ecosystem! agro ecosystem.
Natural resource management, improving soil health by adding sufficient life elements and preserving the same by safe use of inorganic chemicals are the steps to be undertaken when we think about eco-friendly. plantation management; it involves a behavioural change in plantation besides having an awareness. Preserving the natural enemies of pests and diseases by safe and proper use of agrochemicals is yet another contribution.
Eco-friendly Cultivation of Coffee
Eco-friendly cultivation of coffee is aimed at minimizing the use of chemicals and optimizing production which will help us to maintain a clean and safe environment in Shevaroys hills with out affecting profitability in plantation. Adoption of soil and water conservation measures especially in young fields contributes greatly to preserve the environment in its pristine farm.
Contributions can be made to the national/international goal of sustainable agriculture, especially in our plantations through proper soil and water conservation, integrated nutrient and pest management.
Soil and Water Conservation
Shevaroys Plantations are situated at an elevation ranging from 2500 to 5200 feet from MSL where the rainfall ranges between 45" and 60" per annum. The drought experienced in between the rainy days is some times severe which the excess rainfall cannot compensate. Hence, conserving the rainwater effectively required by way of improving soil water holding capacity, which is possible, by adopting proper soil and water conservation measures. Regulating soil temperature is important. Prevention of soil erosion is also necessary. The following are certain measures:
Staggered Trenches
In yercaud, as coffee is mostly grown in hilly slopes, there is a need to prevent the erosion of the top fertile soil. In established plantations, opening of staggered pits (cradle pits) (20 inches wide, 10-12 inches deep) across the slope in between the coffee rows would not only help in prevention of soil erosion but also in better harvesting of rain water and conservation of soil moisture for dry months. These pits also act as in situ compost pits for leaf litter, weed biomass and shade tree lopping. These pits are to be renovated every year just before the onset of southwest monsoon.
Shade Management
Shade plays a vital role in maintaining the ecosystem and required microclimate in coffee plantations. It is better to maintain a two-tier mixed shade canopy consisting of a lower canopy of temporary shade trees like dadap and a top canopy of permanent shade trees belongs to Albezia, Jack, ficus, jumbolina etc. The optimum shade requirement would be 50% for arabica coffee and 30% for robusta coffee. The branches of dadap should be lopped just before the onset of southwest monsoon to facilitate better light penetration during monsoon. Towards the end of monsoon the new regenerated branches should be thinned out to retain an umbrella frame for providing shade during post monsoon period. The canopy of permanent shade trees should be regulated once in two years to provide optimum shade.
In shaded area the organic matter content of the soil will be much more than unshaded area. Regulated shade will help managing the pests and diseases effectively. By maintaining the optimum shade, the incidence of pests such as white stem borer and green scale and diseases such as leaf rust and black rot can be brought down considerably in arabica coffee. Similarly, the shot hole borer incidence can be minimized in robusta coffee. Velocity of falling rain water is reduced by shade trees and hence reducing soil erosion.
Mulching
This is one of the age old proven cultural practices in minimizing soil erosion regulating soil temperature, conserving moisture, suppressing weed growth and enriching the soil with addition of organic matter. Mulching can be done with Guatemala grass, weeping love grass, prunings, shade loppings and other plant materials. Effective mulching of young fields can be achieved with 15 to 25 tones of plant materials per. hectare. Mulching and trenches helps reducing the soil loss to the tune of 1 - 2 tones/ha as against 4048 tones without these conservation measures which has been~ thoroughly studied in Nilgiris, a similar hill station.
Inter/Cover Cropping
To avoid the time lag in soil rehabilitation, which would other wise result in severe soil erosions, inter cropping can be practiced. Short duration leguminous crops like French beans, Soya beans and Bengal gram can be promising inter crops in new clearings. These crops suppress weed growth, help in conserving moisture, provide mulch materials and fix nitrogen, enriching the soil organic matter besides generating additional income. Some of the inter crops like ginger and turmeric in rows are very commonly grown in Wayanad, Kerala.
The above practices amply contribute to the building up organic matter content and fertility of coffee soils. The availability of soil nutrients could be further enhanced by use of bio-fertilizers, which consists of beneficial micro-organisms responsible for nitrogen fixation and phosphorus solubilization.
Weed Management
Weeds can be controlled by manual weeding or by scuffling without using chemical weedicides. Mulching with weed slashing and shade tree leaf litter etc would also be beneficial in suppressing the weed growth especially the grasses. Use of herbicide with appropriate adjuvant and application technology will reduce the impact on the soil beneficial micro-organisms.
Natural Resource Management
The by-products of coffee process namely coffee pulp and cherry husk are rated higher than cattle manure in terms of their manure value and soil conditioning properties. For every tonnes of clean coffee produced on the estate, one tonnes of dry coffee pulp or cherry husk is produced. There by products recycled after composting would contribute approximately 17 Kg of nitrogen, 1.0 Kg of Phosphorus, 52 Kg of Potassium, 1.0 Kg of Sulphur, 5.0 kg of Calcium and 1.0 Kg of Magnesium.
The coffee processing by-products can be composted along with weed bio-mass, with in the estate by following aerobic Hep method. Use of fungus like Trichoderma and Pleurotus will be very effective for decomposing. One has to check up the CN Ratio to confirm the decomposition. The C:N ratio should be minimum of 1 : 20 ., narrow C : N ratio is ideal.
Integrated Nutrient Management
Yield level of coffee estates in Yercaud has increased possibly by a series of breakthrough achieved by implementation of research findings on various aspects of coffee cultivation. The use of chemical fertilizers in coffee nutrition management is one of the most important factors. The large scale use of chemical fertilizers and other chemical inputs used for achieving higher production has indirectly brought about environmental hazards affecting the eco-edafic system. With the unprecedented hike and also the ever-increasing price of the NPK Fertilizers, there has been an increasing interest in finding the alternative sources of plant nutrients. In this context, it may be stated that Integrated Nutrient Supply System (INSS) which involves the combined use of different nutrient sources such as organic manures, biofertilizers and chemical fertilizers appears to be a promising and economically viable system in coffee nutrition management.
Chemical Fertilizers and Integrated Plant Nutrient System
It is scientifically well organized that adoption of an Integrated Plant Nutrient System (IPNS) ensures greater sustainability of agriculture. For INPS, nutrients need to be added to the soil in optimum ratio, which is determined on the basis of the inherent status of available nutrients in the soil and the requirement of the crop. Sound scientific ratio of nutrients has to be obtained based on the analysis of the specific plot of the land. The chemical fertilizers are costlier and non-renewable and also cause environmental concerns. The need for supplementary or cheaper sources of nutrients is recognized. Organic forms of nutrients through crop residues, dungs, city compost, green manuring and use of bacterial fertilizers constitute a potential renewable source of nutrient supply to crops under all situations. This new approach to farming, often referred to as sustainable agriculture, seeks to introduce agricultural practices that are friendlier to the environment and that maintain the long-term ecological balance of the soil ecosystem.
Microbial Inoculants
Use of microbial' inoculants In agriculture (biofertilizers, photostimulators and biopesticides) represents an attractive environmentally friendly alternative to further applications of mineral fertilizers and chemical pesticides. Biofertilizersare microbial products that provide directly or indirectly, plant nutrients and / or stimulate plant growth and increase yield.
Biofertilizers are widely accepted as low cost supplements to chemical fertilizers and have no deleterious effects either on soil health or environment. Biofertilizers which can supply nitrogen and phosphorus - two major plant nutrients, have been developed. Biofertilizers include nitrogen fixing bacteria, efficient urea utilizing bacteria and phytotoxicity reducing microorganisms.
Integrated Pest Management
Use of tolerant / resistant cultivars, manipulation of microclimate through shade regulation and pruning etc. use of eco-friendly approaches like biological control can primarily tackle pests and diseases. Only when there is necessity chemical pesticides can be used with appropriate application technology. Spray volume may be restricted to the required level and use of spray adjuvant will be helpful. Some of the approaches for pest and disease management in coffee estates, which will help in reduction of pesticide load are as follows:
White stem borer: This pest is exclusive to arabic a coffee. Cultural measures like providing optimum shade, regular tracing and immediate burning of affected plants, bark scrubbing to remove crevices on the main stem and thick primaries would be highly effective in checking the incidence of this pest. Spraying of neem formulations on to the main stem once in 10 days or swabbing the stem and thick primaries with 10% lime solution, coinciding with the flight periods of adult beetles would prevent egg laying activity of the insect. Use of pheromone traps (one the technology is standardized) may help in monitoring the pest incidence levels for under taking appropriate control measures as well as in the reducing the pest incidence. Adopting, a community approach with a village or zone would be the most ideal approach to combat this dreaded pest.
Coffee berry borer: This pest attacks the berries of both arabica and robusta coffee. This pest could be effectively by adopting cultural, phytosanitary and biological measures. Proper integration of measures like removal of all season berries, timely and clean harvesting, prevention of gleanings using picking mats, collection and burning of affected gleanings, timely sprays of Entomopathogenic fungus Beauveria bassiana, trapping the beetles in the field using ethyl-methyl alcohol traps and trapping in drying yard using plastic sheets coated with sticky substances would help in bringing down the pest incidence well with in the threshold level. A community approach with in a village or zone in implementing the control measures would greatly help in combating this serious pest. Strict quarantine measures would help in prevention of spread of this pest to new areas. Exotic parasitoid like Cephalonomia stephanoderis is provided beneficial in control of the pest.
Mealy bugs: This pest is generally seen in exposed areas and irrigated blocks in both arabica and robusta. By providing optimum shade and release of exotic parasitoid Leptomastis dactylopii this pest could be effectively controlled. Some times root mealy bugs may pose a problem in young coffee. Drenching . the soil around the root zone with neem oil solution may be helpful to control root mealy bugs.
Leaf rust: This disease attacks Arabic coffee. Maintaining optimum shade, judicious pruning and spraying of 0.5% Bordeaux mixture as pre-monsoon, midmonsoon and post monsoon applications would effectively control the leaf rust disease.
Root Diseases
Four types of root diseases namely brown, red, black and Santa vary root diseases occur in endemic patches only. Of these the first three diseases attack both arabica and robusta, while the later is specific to arabica only. Generally the decaying stumps of shade trees harbour these diseases which later spread to nearby coffee bushes. The following measures are suggested to prevent the spread of root diseases to neighbouring areas and recover the infected areas.
- Uprooting of shade tree stumps after timber extraction
- Uprooting and burning of affected coffee bushes.
- Making an isolation trench around the affected plants by including a ring of surrounding healthy plants.
- Application of 1-2 Kg of agricultural lime to the uprooted pit and exposing the spot for at least six months.
- Application of 5 to 10 Kgs/plant of well decomposed FYM / compost mixed with trichoderma and pseudomonas to the surrounding healthy plant.
References
Coffee Board and UPASI Documents.
Conclusion
To design production system that effectively reduce discharges from agricultural production activities, resource managers must understand that these activities are conducted with in the context of natural systems that are largely driven by stochastic natural processes and natural inputs. The term agro environmental system emphasizes this linkage. A reasonable use of nitrogenous fertilizer/chemicals through nutrient and pest management would harmonize the need to limit the loss of nitrogen in to the environment and the requirements of efficient agriculture. Thus by training and organizing the growers it will be possible to reconcile the needs of agriculture and satisfactory quality of ground water. Decisions on action need to be taken soon, however, if changes in agricultural land - use practices are to be effective in avoiding the need for water treatment because ground water systems will only respond slowly to a reduction in nitrate leaching.
