Ebooks

Foreword The major plantation crops in India include coconut, cashew nut, cocoa, coffee, tea, rubber and spices like cardamom and pepper. The area under plantation crops in India is significant covering around 4271 thousand hectares. In terms of production, the total yield of plantation crops in India was approximately 16.05 million tons during the year 2022-23. Year to year variation in production can be attributed to several factors including climate change, weather variability and market fluctuations. The production of plantation crops has shown steady increase at the rate of 2.99 per cent per annum. The plantation crops contribute 10 to 12 per cent to India’s agricultural GDP. India is a significant exporter of plantation crops, generating substantial foreign exchange in addition to providing livelihood for millions of rural households. The key producing states are Kerala, Karnataka, Andhra Pradesh, Tamil Nadu, Orissa, West Bengal and Assam. Most of these plantation crops are grown from sub humid to per humid climates in Peninsular and eastern parts of the Country. Coffee and tea are grown on mountain slopes in per humid climates.

Coconut, cocoa (cacao), coffee, cashew, cardamom, black pepper, tea, rubber, oil palm and areca nut are the major plantation crops that are perennially grown along the coastal belt in southern States of the Country and to some extent in high rainfall zones of the northeastern States of India. These crops are also known as perennial crops. The life span of these crops varies from fifteen to sixty years or more depending upon the crop and its management. Coconut and cashew are also popularly known as the coastal trees. Cardamom and black pepper are also known as the spice crops. Once these plantation crops are well established, they mature for fruiting in three to eight years depending upon the nature of plantation crops and the crop management. The reproductive phase is seen round-the-year in case of coconut and cocoa. Cashew is one of the plantation crops with seasonality in fruiting from September to June. Cocoa is mostly grown as an intercrop in coconut gardens and in some pockets as a pure crop. Black pepper is trained to coconut and areca nut in many locations and seen as mono crop as well. All these crops are grown in laterite, sandy and alike in well drained soils. The hill slopes with terrace cultivation are also suitable for all the plantation crops. Tea, coffee and cardamom are seen on hillocks extending up to the base. Some of the plantation crops are seen in multitier cropping system as well as mixed/intercrops/homestead gardens. They are grown mostly under the rain fed and summer irrigation is beneficial for better harvest. The plantation crop distribution, production and productivity are influenced by air temperature, rainfall and the other meteorological variables viz. sunshine, cloud cover, solar radiation, vapour pressure, evapotranspiration, humidity and wind. Interestingly, coffee spread in Wayanad District while cardamom in Idukki District. Coffee experiences unimodel rainfall while bimodal in the case of cardamom.

Cashew (Anacardium occidentale L.) is a native of Brazil and was introduced in India by the Portuguese during the16th Century. It is grown in India, Brazil, Vietnam, Tanzania, Mozambique, Indonesia, Sri Lanka and other tropical Asian and African countries. The crop is grown within the latitudinal belt of 27°N and 28°S of the equator experiencing the tropical climates for its growth and development. It is categorised under one of the plantations along the West and East Coasts. To a limited extent cashew is cultivated in Gujarat, Chattisgarh, Manipur, Meghalaya, Tripura, Andaman and Nicobar Islands. The crop is mostly grown in low and midlands along the West and East Coasts of India in sandy and laterite soils. Since it is mostly grown along the Coast across the Country it is also known as the Coastal Tree. Cashew grows along the West and East Coasts of India from South to North, lying between 09°N and 23oN latitudes. Though it grows beyond 23°N latitude, its production is relatively low as the reproductive phase coincides with cold injury/low temperature during winter (December-February). Being a tropical coastal tree, it cannot thrive under low winter temperature. There is significant yield variation in cashew among the different agroclimatic zones of the country. Year-to-year yield variation is also significant as the crop is weather sensitive. This crop may come up even in waste lands with specific crop management practices along the West Coast and as a shelter belt and wind break along the East Coast.

The Coconut palm, also known as the Cocos Nucifera L., is one of the most fascinating and beautiful palms in the world. The coconut is believed to have originated in southeast Asia (Indonesia, Malaysia, Philippines) or Micronesia. Coconut has been cultivated in India since ages and plays an important role in social, economic and cultural activities of the people. The palm is amenable to both plantation and homestead management and it can be either a major crop or a minor one in a homestead garden of mixed crops. While responding favourably to scientific management, the palm also tolerates negligent farming to a certain extent. Thus, it can adapt to the divergent farming situations and management practices that are prevalent in different agro-climatic regions. The coconut palm is usually found near the sea on sandy beaches where it can tolerate salt spray and brackish soils. It is also grown under different soil types such as loamy, laterite, coastal sandy, alluvial, clayey and reclaimed soils of the marshy low lands. The ideal soil conditions for better growth and performance of the palm are proper drainage, good water holding capacity, and presence of water table within three metres and absence of rock or any hard substratum within two meters of the surface. The coconut palm can also grow well inland, within altitudinal limit of 600 m to 1000 m in the Tropics. It requires an equatorial climate with high humidity. A year-round warm and humid climate favours thegrowth of coconut. The palm does not withstand prolonged spells of extreme weather/climate variations under rain fed conditions. A welldistributed rainfall of 1300–2300 mm per annum is preferred. It is known as a coastal tree since it is grown along the Coasts and Islands and does not tolerate high diurnal temperature range, that is the difference between the maximum and minimum temperatures.

Cocoa is popularly known as cacao in many cocoa growing nations. Cocoa beans are the source of commercial cocoa. The cocoa products viz., cocoa liquor, cocoa butter, cocoa cake, cocoa powder and cocoa chocolate are widely consumed across the World. Cocoa powder is essentially used as flavour in biscuits, ice cream, dairy drinks and cakes. Apart its use as flavour it is also used in the manufacture of coatings for confectioners or frozen desserts. Cocoa powder is also consumed by the beverage industry for example for the preparation of chocolate milk. Besides the traditional uses in chocolate manufacture and confectionery, cocoa butter is also used in the manufacture of tobacco products, soap and cosmetics. It is also a folk remedy for burns, cough, dry lips, fever, malaria, rheumatism, snakebite and wounds. It is reported to be antiseptic and diuretic. Looking at the industry needs for various purposes, there is a heavy demand for cocoa. At present, the gap between supply and demand in cocoa appears to be more at the national level. To fill the gap, various agro-technologies and crop improvement strategies are to be chalked out, for which the response of the crop to various environmental factors are to be understood. Weather aberrations during the flowering and fruiting result in the final cocoa production. Therefore, it is important to understand the effect of weather on flowering and fruiting pattern of cocoa to minimize the crop losses against the weather abnormalities. Though it is known that cocoa yield is highly variable and sensitive to various weather factors, the studies on crop weather relationships in cocoa and its response to climate change/variability are relatively scant

Small cardamom (Elettaria cardamomum Maton), popularly known as the “Queen of spices”, occupies an important position among the foreign exchange earning commodities. It is cultivated on a commercial scale in Sri Lanka, Guatemala, Tanzania and Papua New Guinea. Guatemala is the largest producer of cardamom in the World. In India, it is confined to the States of Kerala, Karnataka and Tamil Nadu. Among these States, Kerala accounts for the major portion of production (58.4 %), followed by Karnataka (35.2 %) and Tamil Nadu (6.4 %). In Kerala, Cardamom is mainly grown in the erstwhile Travancore area in Idukki district and it is known as the Cardamom Hill Reserve (CHR). Cardamom is a native of the moist evergreen rain forests of the Western Ghats and is grown extensively in the hilly regions at elevations of 700 to 1300 metres as an under crop in forest lands. Cardamom thrives well within certain maximum and minimum thermal regimes. It is believed that diurnal symmetries in temperature trends, if any, have close links with the changes in cloudiness, humidity, atmospheric circulation pattern, winds and soil moisture. The land use pattern of cardamom tracts has changed to a great extent in recent decades. Crops like coffee, black pepper and areca nut are being cultivated at many locations in place of cardamom. With denudation of forests in many cardamom areas, the ideal cool humid microclimate has been destabilized and adversely affected the productivity of the crop.

Arabica coffee is reported to have originated in the tropical rain forests in Ethiopian highlands while Robusta is a native of the humid tropical lowlands of Central Africa, probably, Uganda. The major coffee producing countries across the World are distributed between 23°N and 23°S of the equator. Beyond these latitudinal limits, temperature becomes a major limiting factor as coffee plants are sensitive to extreme temperature regimes. Thus within the latitudes, altitude becomes a major factor. In areas, nearer to the equator, coffee plants require higher altitudes when compared to farther north and south (6.1 plate). The world’s largest coffee producer is Brazil with around 30% of total world output of coffee. Columbia comes in second with around two thirds of Brazil’s production. India is the sixth largest (after Brazil, Columbia, Vietnam, Indonesia and Ethiopia) producer of coffee. Coffee is reportedly introduced into the Western Ghats regions of South India around 1600 AD. However, commercial cultivation of coffee was opened in South India with the British enterprise and investment during late 1820s. Coffee occupies an important position among the plantation crops in India. It is cultivated mainly in the traditional States of Karnataka, Kerala, Tamil Nadu and to some extent in non-traditional areas viz., Andhra Pradesh and Orissa as well as in North Eastern States viz., Assam, Manipur, Meghalaya, Mizoram, Tripura, Nagaland and Arunachal Pradesh. Coffee in India is unique. Almost all coffee plantation are grown under the shade of forest/planted trees, where as it is grown under open conditions in all the major producing countries viz., Brazil, Vietnam and Columbia.

Black pepper (Piper nigrum L.), famous as “Black Gold” and also known the “King of Spices” is the most important agricultural commodities of commerce and trade in India. It is the most important, most popular and most widely used spice in the World. Of the total spices traded internationally, black pepper accounts for 34 per cent. South West India is the traditional home of this important spice, particularly the Malabar Coast. Black pepper is also grown in tropical zones such as the Asia Pacific Region, mainly India, Indonesia, Malaysia, Sri Lanka, Thailand, China, Vietnam and Cambodia. Outside the Asia Pacific region, the crop is distributed in Brazil, Mexico, Guatemala, etc., totaling about 26 countries. It is grown successfully between 20°N and 20°S latitude and from mean sea level to 1500 meters above sea level. World’s black pepper production varies in the range of 2.7 to 3.35 tonnes annually. The major production share is contributed by Vietnam with an annual production of 80,000 tonnes. About 85 per cent of the World trade of pepper is determined by the largest pepper producing countries in the International Pepper Community (IPC). World export fluctuates around 1.5–2.5 lakhs tonnes per annum. Global black pepper supply has shown a drastic increase over last ten years except in 2008–09. Vietnam’s sudden increase in production has resulted in the massive global out put of 3–3.5 lakhs metric tonnes from 1.9–2.0 lakhs metric tonnes in late nineties. 

Tea (Camellia sinensis) is one of the most important beverage crops in the World and the second most commonly drank liquid on earth after water. It has numerous medicinal benefits mainly due to its antibacterial and antioxidant properties. The major tea growing regions of the world are South-East Asia (India and Sri Lanka), Eastern and South Africa consisting of Kenya, Malawi, Tanzania, Uganda and Mozambique. All these countries are producers of black tea. China and Japan are the major producers of green tea. These countries experience cool, tropical humid climate where this crop is being cultivated. However, at present, the crop is also being cultivated in wide range of climates from Mediterranean to warm, humid tropics to include countries such as Russia and Georgia in the northern latitudes and Argentina and Australia in the southern latitudes (Plate 8. 1). The region to which the crop is grown is closely linked with the climate. The crop is grown across wide altitudes up to 2200 m a.m.s.l. Sri Lanka, Kenya, China and Vietnam are the major competitors to India in tea exporting field. China is the major producer of green tea while Sri Lanka and Indonesia are producing mainly orthodox varieties of tea. Tea industry in India occupies an important place in the national economy since last 172 years. It is an essential item of domestic consumption. Tea is also considered as the cheapest beverage amongst the beverages available in India.

The natural habitat of rubber (Heavea brasiliensis) is rain forests of the Amazon basin, situated within 5° North and South at altitudes below 200m. The climate of this region is equatorial monsoon type characterized by mean monthly temperature by 25 to 28°C, well distributed rainfall and no marked dry weather. Though it is originated in the Amazon basin, it is now predominantly grown in the tropics where an equatorial monsoon type climate prevails. Regions between 8°N and 10°S which includes Indonesian archipelago, Malaysia, southern part of Sri Lank  and some other Islands, are better suited to rubber cultivation. The production of natural rubber in the country was 8.65 lakh MT in 2008–09, registering a 4.74 per cent growth compared to the previous year. India is the fourth largest producer of natural rubber with a share of eight per cent in the World after Thailand, Indonesia and Malaysia and the fourth largest consumer of natural rubber after China, USA and Japan. Among the rubber growing countries in the World, India occupies a pride place with the top most position in productivity (Table 9.1). The productivity of natural rubber (NR) in India in 2009–10 was 1784 kg/ha. In 1950–51, it was 284 kg/ha. The growth achieved in terms of the productivity of natural rubber is 628 per cent. This achievement

Coffee is grown at higher elevation across the Western Ghats between 750 and 1200 m amsl. It requires a certain degree of shade for its better performance.  The annual rainfall over the coffee growing tracts varies between 1400 and 2600mm, having uni/bi-model rainfall with prolonged dryspell from November to May. It is more so over North of the Western Ghats. The mean annual maximum temperature varies between 24 and 300C while the minimum between 15 and 180C. The difference between maximum and minimum temperatures (temperature range) varies between 5 and 160C across the coffee tract. The ‘Monsooned Malabar Coffee’ is a specialty coffee produced from the erstwhile ‘Malabar Region’. It undergoes certain changes in physical and biochemical characters when the coffee beans are processed during the summer monsoon (June to September). It is processed at Mangalore, located in Coastal Karnataka. The processing location experiences heavy rainfall of more than 1000 mm in July, followed by 950 mm in June and 600 mm in August. Out of 3264 mm of annual rainfall, 2852 mm is received during the monsoon period. It accounts more than 80 per cent of annual rainfall. The maximum temperature during the coffee monsooning period varies between 28 and 30°C while night temperature revolves between 22 and 24°C. Being located in the tropics along the West Coast, the crop processing environment in terms of surface air temperature is relatively uniform and moderate with a characteristic feature of heavy clouds and continuous rainfall during the monsoon period. These monsoon features are more predominant from the middle of June to August during which the coffee beans are subjected to monsooning. The coffee beans bulge in the process of monsooning and the volume increases significantly due to absorption of atmospheric moisture. It is directly related to the monsoonal wind during which coffee beans are processed. The bulging was less in all the samples processed during monsoon 2003, which varied from 2.1 to 2.7 ml/100 number, while it ranged between 2.7 and 5.8 ml/100 number in the samples processed during monsoon 2004.

The global economy has adversely been affected to a considerable extent due to weather related disasters like droughts, floods, heat waves and cold waves which are not uncommon in the recent past due to global warming and climate change. For the first time, the year 1998 was declared as the weather related disastrous year globally. The year 2015 was the warmest year globally, again. Such weather phenomenon of warming more and more year after year was noticed in the current decade as well when we look at 2023 and 2024. The year 2010 was the warmest year ever recorded, followed by 2009 in India. The occurrence of floods and droughts, cold and heat waves adversely affected the Indian foodgrains production to a large extent across the Country in one or other region as seen in 2014, 2012, 2009, 2004, 2002 and 1987. The cold wave in winter 2003- 04 across the Northeast region of the Country and the heat wave in summer 2004 across the same region are still in memory to understand the ill effects in agriculture/horticulture/poultry/inland fisheries sectors. Model simulations indicate that a marked increase in rainfall and temperature over India would be seen during the current century. The maximum expected increase in rainfall is likely to be 10–30% over the Central India. Temperatures are likely to increase between 2 and 30Cby the end of 2100 A.D. However, steps taken towards the green energy across the world may yield results not to allow atmospheric global temperature beyond 1.5 to 20C. Greater number of high surges and increased occurrence of cyclones in post monsoon period along with increased maximum wind speed are also expected along the East Coast of the Country. The summer droughts and heavy rains leading to waterlogging, floods and landslides during the monsoon period is a threat to plantation crops which are predominantly grown in the Humid Tropics like Kerala (8°15` N and 12°50`N latitudes and between 74°50`E and 77°30`E longitudes).

The Government of India, during 1980s, recognized the necessity to improve the latex yield productivity in the traditional rubber growing regions and also expand these plantations to non-traditional regions to meet the ever increasing demands of natural rubber in India (Sethuraj et al., 1989). Agrometeorological studies were initiated during early 1986 with the appointment of a Scientist (Agrometeorology). To begin with, scientific issues were identified as: (a) delineate the potential non-traditional regions for expansion of rubberplantations, (b) estimate the impact of climatic conditions, especially abiotic  stress conditions on productivity, (c) quantify influence of meteorological factors on the physiological responses towards plant growth and yield attributes, (d) estimate the irrigation requirements to mitigate the drought conditions, and (e) develop weather based predictive models for `Abnormal leaf fall’ disease of rubber plantations. An attempt is made to present synthesis of accomplishments during 1986 to 1992 period of my association with the Rubber Research Institute of India (RRII), Kottayam.