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Raw cashew nuts are a seasonal commodity and the trading season is from March to May. Growers usually supply the primary or village markets where small traders collect and supply the urban markets. The cashew trade is seldom handled by exclusive traders. Usually, those traders who collect other plantation products also trade in cashew. Due to the highly competitive nature of the cashew trade, growers have few marketing problems. When large quantities are collected by middlemen, the processors enter the marketing chain and make wholesale purchases. Grades and standards for cashew are yet to be introduced in India. Quality is generally determined by appearance and cutting tests that traders employ prior to purchase. The raw cashew nut market involves a large amount of capital where nearly 80 per cent of the produce is transacted within a period of 35 days. The current value of Indian production is estimated at around Rs. 10,000 million. This capital is made available by industry for procurement and processing operations.

There are no growers’ cooperatives or organizations for cashew marketing. In Kerala, however, the government has been involved in the procurement process and supply to large-scale processors. This adversely affected the cashew trade and has now been replaced by a free market policy.

In addition to the local production of nearly 7 lakh tonnes, India also imports a considerable quantity of raw nuts from several African and South-east Asian countries to satisfy the national processing capacity of about 12-14 lakh tonnes established in the country.

Introduction

Once the cashew fruits fallen, are collected, the nuts are to be separated from the cashew apple and sun dried for 2 to 3 days. This is very important in view of the quality of kernels obtained during subsequent processing. Raw nuts at the time of harvest will have moisture content ranging between 16 to 25 per cent; while sun dried nuts have moisture content of 8 to 10 per cent (Nagaraja, 2000). If the nuts are not dried and stored properly, it leads to fungal spoilage resulting in poor quality of kernels. Fungi such as Gonatobotryum, Helminthosporium sp., Corynespora sp., Alteraaria sp., Verticillium sp. and many species of Aspergillus have been isolated from stored cashew nuts (Joseph, 1981). In view of the occurrence of fungi, drying of the raw nuts before storage becomes absolutely essential. Maximum permissible moisture content of raw cashew nuts is 8.7 to 9.1% (Ohler, 1979). Okwelogu and Mackay (1969) have reported that high whole nut or kernel moisture percentages are closely associated with high shell moisture contents and for nuts whose moisture content is in equilibrium with the ambient relative humidity, the moisture content of whole nut and kernel could be predicted from that of shell with more than 99% accuracy. A higher kernel shell weight ratio has been shown to be inversely proportional to moisture content.

Maturity of Cashewnut

Cashew fruit has two parts namely cashew nut (actual fruit) and cashew apple (pseudo fruit). Development of these is not parallel. Cashew nut develops first and the pseudo fruit develops later. It takes 60 days for both the nut and the pseudo fruit to develop completely since anthesis. Development of cashew apple and nut has been studied by number of workers in different cashew varieties (Rao et al., 1962; Augustin and Unnithan, 1981; Mohan Kumar et. al., 1984; Antarkar and Joshi, 1987). According to the report, specific gravity could be considered as physical index of maturity of nut in cashew varieties of V-1, 2, 3, 4 and 5 (Antarkar and Joshi, 1987; Mohan Kumar et al., 1984). In Thailand, the nut reached maximum size in 4 weeks after fruit set, hardened in the subsequent week and declined in size by 10 per cent at harvest (Sumrit Feungehan et al., 1989). Augustin and Unnithan (1981) have reported that the growth of nut is faster during early stage of development than that of fruit. All these reports indicate that the cashew nut develops earlier than cashew apple. Changes in the composition of cashew nut and apple during development have been looked into by various workers. Hariharan et al. (1985) have reported decrease in amino acid content in kernel with increased maturity. Cashew kernel lipid, free amino acids and CNSL have been shown to increase with increased maturity. Similarly, cashew kernel phenols have been shown to decrease with maturity. Changes in the kernel sugars and starch were not uniform (Anon., 1998).

In the orchard, several cultural operations like weeding, mulching, etc. are very important. Similarly protection from fire is also essential. The points are discussed here.

Weed Management

The Luxuriant weed growth is a common sight in neglected old cashew gardens. Weeds are not only harmful by competing for the nutrients and moisture but also cause inconvenience to take up effective plant protection measures and harvesting of fallen nuts; thus resulting in loss of yield. Therefore, sanitation of cashew orchard is very essential, it also minimise the incidence of cashew stem and root borer (CSRB). Careful weeding-clearing the area within 2 m radius of the trunk is essential. Clearing of weed growth is to be carried out twice in a year. Weeds may compete for nutrients and moisture with cashew. The weeding cycles are generally confined to the pre-monsoon and post-monsoon periods to coincide with the fertilizer application.

Weeds should also be controlled between the rows. This can be done by inter-cropping with certain crops for 3/4 years before the tree canopies close in. In addition a legume can be grown to both control weeds and fix nitrogen for the trees. This improves the soil and makes the nutrient available.

In the field of agriculture/horticulture, various irrigation systems are being employed to fulfil the water requirement for better growth and development of the tree. Since, cashew is hardy plant which can sustain in rainfed conditions of warm and humid region; it has very good potential to produced higher nut yield. Of the various irrigation methods, drip irrigation system is best method in the areas where natural resources of water is limiting factor. It is well known fact that this system has many advantages.

During the first year after planting, protective irrigation is recommended at 15 days interval during winter and at 8 days interval during summer season. At each irrigation, 25 litres of water to be given per graft. The studies on mulching and irrigation were under taken with a view to determine fruit retention. It was observed that black polythene mulch with irrigation @ 60 liter of water per tree at 15 days interval showed beneficial effect on increasing fruit retention (66.15%) over control. Cashew is grown under rainfed conditions. However, supplementary irrigation during summer months, especially during January-March at fortnightly intervals @ 200 litres/plant proved to double the yield. This is evident from the research results obtained at NRC-Cashew, Puttur (Karnataka).

Pruning in young tree during initial stage help to form a strong frame work for better growth and development of the tree. However, on long term way, the tree becomes huge with gigantic canopy results in to problem of majority of agronomic operation, plant protection and harvesting of crop. Top working provides an opportunity to control the growth of tree and makes the tree productive with manageable canopy, in old and senile orchards.

Top working is a technique evolved to rejuvenate the unproductive and senile cashew trees. Poor yielding trees of 5-15 years of age can be successfully rejuvenated by top working. The unproductive trees are to be headed back to a height of 1.00 m from the ground level in October-November. The stem should be sawed off to avoid stump splitting. Soon after beheading, the stumps and cut portions should be given a swabbing with carbaryl 50% WP (50 g each per litre of water) or Bordeaux paste. Sprouts emerge 30-45 days after beheading. Sprouting will be profuse in young trees. So, it is better to keep only 4-6 healthy shoots on beheaded tree spreading in all directions and similarly the sprouts which come out from ground level (most probably water shoots) also removed frequently. On 30-45 day old shoots, graft scions of high yielding varieties following soft wood grafting technique. On each tree, 4-6 grafts are to be done to ensure at least 3-4 successful grafts per tree. The best season for grafting is March-April. Thinning of the extra shoots arising from the stumps should be done to obtain better growth of the grafts. Removal of sprouts below the graft joint and removal of polyethylene strip from the graft joint should be done. Top working is simple and can be done by farmers themselves after getting proper training. The top worked trees start yielding right from the second year of top working. Early bearing can be treated as one of the best advantages of this technique. The major disadvantage associated with top working is the huge casualty of trees due to stem borer attack. Intensive care and management to ward off stem borer is essential. As such adoption of top working on a larger scale would be difficult.

Canopy management is the manipulation of tree canopies to optimize the production of quality fruits. The canopy management, particularly its components like tree training and pruning, affects the quantity of sunlight intercepted by trees, as tree shape determines the presentation of leaf area to incoming radiation. An ideal training strategy centres around the arrangement of plant parts, especially, to develop a better plant architecture that optimizes the utilization of sunlight and promotes productivity. Light is critical to growth and development of trees and their fruits. The green leaves harvest the sunlight to produce carbohydrates and sugars which are transported to the sites where they are needed – buds, flowers and fruits. Better light penetration into the tree canopy improves tree growth, productivity, yield and fruit quality. The density and orientation of planting also impact light penetration in an orchard. Generally, in close planting, quicker shading becomes a problem. An east-west row orientation results in more shading as compared to the western and southern orientation of trees. Strong bearing branches tend to produce larger fruits. The problem of a fruit grower is initially to build up a strong and balanced framework of the trees, then equip them with appropriate fruiting. Obviously, pruning in the early years has to be of a training type to provide strong and stocky framework with well spaced limbs or any other desired shape.

Various studies have demonstrated that the cashew tree responds to the application of mineral nutrients, though the responses are significantly affected by plant age, the genotype utilized, the conditions of cultivation, soil and climate and of the crop management (Barros et al., 1984; Ghosh, 1990; Ximenes, 1995; Bezerra et al., 1999; Crisóstomo et al., 2005). The crop develops well under semi-arid conditions, in which the problems associated with water availability and salt excess in the root environment are common. These two factors interfere with the acquisition of nutrients, in that the levels of nutrients in the plants are affected both by direct effects on absorption and transportation processes and by indirect effects associated with a reduction of growth of the various plant organs including the root system. The effect of salinity on plant nutrition depends on the types of salts that predominate in the cultivation environment which can result in a deficiency of essential nutrients and an excess of toxic ions. These changes under salt stress are accompanied by a loss of structural and functional integrity of the cellular membranes, a reduction in activity of various vital enzymes, and a diminished capacity of the roots to absorb nutrients (Zhu, 2001). On the other hand, water deficit reduces the extraction of nutrients from the soil, limiting the solubilization of nutrients in the root environment and altering the morphology of the root system (Kramer and Boyer, 1995). It should be added that the effects of excess salt and water deficit depend on various factors, including the species under study and the stage of development at which the plants are submitted to these.

Selection of Site and Land Preparation

Cashew is a hardy plant; it thrives well on wide range of soil. While selecting the land for cashew, soils with water logging and excessive salinity of alkalinity should be avoided. Otherwise, soil depth, slope, stoniness, soil fertility and water availability seem to impose very little limitation. For establishing new plantations, land preparation should begin with the first pre-monsoon rains. The area should be cleared of bushes and other wild growth before digging pits for planting.

Planting Season

Planting of soft wood grafts is usually done at the beginning of monsoon season (June-July). Therefore, land preparation such as clearing of bushes and other wild growth, digging of pits for planting, should be done during pre monsoon season (April-May).

The emasculation and pollination in any crop depend on its floral structure and biology. Cashew is basically andromonoecious (polygamo monoecious) crop with staminate and hermaphrodite flowers appearing in the same inflorescence or panicle (Rao and Hassan 1957). The hermaphrodite/bisexual/perfect and male flowers occur intermediately in the same panicle in three or four phases viz., Male – Mixed – Male or Mixed – Male – Mixed– Male. Distinct phases depend on genotype and environmental factors. The tree shows considerable variation in the duration of different phases. The hermaphrodite flowers are bigger in size than staminate or male flowers (Damodaran et.al., 1965). Male flower always exceed the bisexual flowers. The flowers produced early in a panicle are mostly male (Rao and Hassan 1957; Damodaran et. al., 1965). Most of the perfect flowers are produced about one month after the first flower occurred in the panicle (Bhat et al., 1998).

Pattern of Growth Flushes in a Bearing Tree

Two or three peak periods of growth are usually observed in a bearing cashew tree, even though under favourable conditions the stray shoot growth may occur almost every month. The pattern of growth of a bearing tree consists of a generative flower flush (reproductive) and a vegetative flush. The vegetative flush, consisting of lateral shoots, always develops soon after the main crop has matured. Flowering is terminal and is universally preceded by the vegetative flush.

There are two types of branching in cashew, intensive and extensive.

Cashew being a highly cross pollinated crop, planting of seedling is not recommended. In the past seed propagation was in vogue, which has resulted into large variation in plants due to highly heterozygous nature. However, it is seldom practiced now-a-days except to raise the rootstock materials. Selection of seed is very important for raising rootstock material. Seed nuts which are heavy and sink in water should be selected for raising seedling. Seed nuts should be collected from high yielding trees. Seed nuts collected from the current season’s crop during March, April and May are the best for seed production as they have been found to give high percentage of seed germination. Studies conducted to investigate the time taken and germination percentage revealed that heavy nuts (sunken in water) gave 92 per cent germination on 14-17 days, whereas floating nuts took 14-22 days and gave 64 per cent germination (Krishnamurthy et al., 1985).

Cashew research in India dates back to 1950’s when Indian Council of Agricultural Research sanctioned ad-hoc schemes in the then composite Madras, Travancore, Cochin and Bombay States. Thus, Kottarakkara (Kerala) in 1952; Ullal (Karnataka in 1953 and Vengurla (Maharashtra) in 1957 came into being as pioneering cashew centres in the country. More research schemes were started with ICAR’s assistance in 1955 at Bapatla (Andhra Pradesh) and in 1956 at Deragaon (now shifted to Kothiali) in Assam. During the period, Central Food Technological Research Institute, Mysore and National Chemical Laboratory, Pune were also engaged in developing technologies for economic utilisation of cashew apple and Cashew Nut Shell Liquid (CNSL). In the second phase of strengthening cashew research in India, the ICAR started All India Spices and Cashewnut Improvement Project in 1971 linking countrywide network among different research centres. Collection, conservation and evaluation of germplasm, hybridization and selection, vegetative propagation, and nutritional studies were the primary areas under this programme.

Maharashtra, the first state was to release cashew variety under the name Vengurla-1 through Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli in the year 1974. So far, 8 varieties have been released from Regional Fruit Research Station, Vengurla (M.S.), of which, Vengurla-4, Vengurla-6, Vengurla-7 and Vengurla-8 are widely accepted for commercial plantation.

Anacardium occidentale is a medium-sized tree, spreading, and evergreen, much branched; grows to a height of 12 m. When grown on lateritic, gravelly, coastal sandy areas, it rarely exceeds 6 m and develops a spreading habit and globose shape with crown diameter to 12 m but, if grown inland on loams; it reaches 15 m tall and is much branched, with a smaller (4-6 m) crown diameter. The root system of a mature A. occidentale, when grown from the seed, consists of a very prominent taproot and a well developed and extensive network of lateral and sinker roots. Leaves simple, alternate, coriaceous, glabrous, obovate, rounded at ends, 10-18 x 8-15 cm, with short petiole, pale green or reddish when young and dark green at mature. Rai and Vatsala (1985) studied the dermal morphology and stomatal ontogeny of Spondias pinnata Kurz., Lannea coromandelica (Houtt.) Merr., Anacardium occidentale L., Holigarna arnottiana Hook. F. and Mangifera indica L. are studied. The cuticle is thick in H. arnottiana, A. occidentale and M. indica, but is thin in S. pinnata and L. coromandelica. Based on the shape of epidermal cells, the five species are categorised into three: cells in both upper and lower epidermis sinuous (A. occidentale, H. arnottiana, S. pinnata); upper sinuous and lower polygonal (M. indica) and upper polygonal and lower sinuous (L. coromandelica). Stomatal ontogeny aperigenous (L. coromandelica), paramesoperigenous (A. occidentale) and anisomesogenous (M. indica, H. arnottiana). S. pinnata is peculiar in that it possesses three different types of stomata, aperigenous, hemiparamesoperigenous and paramesoperigenous; whereas, in all the other four species, only one type of stomatal ontogenesis exists. Except S. pinnata, all the other species possess epidermal appendages. Unicellular trichomes occur in A. occidentale and H. arnottiana, and multicellular glandular trichomes in A. occidentale, M. indica and L. coromandelica. The multicellular hairs are found in A. occidentale in specialized pockets in two rows on either side of the major veins - a unique feature which is reported for the first time.

Soil
Cashew is grown on a wide variety of soils in India. It comes up well in all types of soils at an altitude up to 700 m. It cannot stand in water logged or saline soils. It can come up in very sandy soils also. Adoption of cashew has been found in wide variety of soils from coastal sands to degraded laterites. The worst soils, not suited to other crops, are normally allotted for cashew. In Sri Lanka and Philippines, it is grown in alluvial soils. Cashew comes up well even in volcanic soils of Indonesia, Fiji and some part of Philippines. Cashew is not suitable in heavy clays, water logged conditions and ill drained soils. It is grown abundantly in loose sandy soils particularly in South India, East Africa and Brazil. In Karnataka and Kerala, it grows well in poor laterite soils. Cashew prefers well-drained aerated sandy loam soils with adequate moisture. Coastal plains and plateau are very good for cashew cultivation.

In India, cashew is mostly grown on laterite and red soils and coastal sands. The tree has an extensive root system, which helps it to tolerate a wide range of moisture levels and soil types, but commercial production is only advisable in well-drained, sandy loam or red soils with slight acidic pH (4.5-6). The cashew tree can flourish in the sand of open beaches, but it grows poorly in heavy clay or limestone.

Though cashew can be grown on a variety of soils, a well-drained 1-1.5 m deep soil having a water table between 2 and 10 m depth and pH of 5.6 to 7.0 is preferred. Laterites, red and coastal soils rich with organic matter are best for cashew growing. Even the marginal soils can be used for cashew cultivation but the waterlogged condition should be avoided as the cashew is very susceptible to it (Farooki and Sreeramu, 1999).

Global Scenario

Globally, India’s share in the cashew area and production is 20 per cent and 16 per cent, respectively. India occupies the largest area followed by Ivory Coast (19%), Brazil (16%), Indonesia (12%), Vietnam (7%), Nigeria (7%), Benin (5%), Guinea-Bissau (5%), Mozambique (2%) and Philippines (1%). The highest production was from Vietnam (30%) followed by Nigeria (19%), India (16%), Ivory Coast (11%), Brazil (5%), Indonesia (3%), Philippines (3%), Guinea-Bissau (3%), Benin (2%) and Mozambique (2%). Sometimes back, India was credited as largest producer, processor and exporter of cashew in the world but as other cashew producing countries also acquired the know-how of processing and entered in the international market, currently the India’s share in the International market has shrank to 30 per cent only. On the other hand, the domestic consumption in India has increased considerably, owing to largest consumption of cashew kernel. Every year, over 7-8 lakh tonnes of raw cashew nut are imported mainly from African countries and exporting cashew kernel to USA and UK after processing (Saroj, 2013).

Cashew has a long history as a useful tree but only in the current century, it became an important tropical horticultural crop. Small-scale local exploitation of cashew for its nuts and cashew apples is the pattern for more than 300 years in Asia and Africa. It was not until early years of 20^th century that international trade in cashew kernels began with first exports from India. Although with slow beginning, cashew became an important commercial crop in the last couple of years. In India, use of cashew apples and nuts was started by local people, and accounts from Africa are similar; making cashew wine/liquor possessing a common practice in both Asia and Africa (Johnson, 1973).

Cashew, an evergreen tree, produces both nuts and apples, has become a crop of importance owing to the highly valued kernel and wide adaptability to varying agro-climatic conditions. India is one of the largest producer, exporter and consumer of cashew in the world. Today, cashew has become a crop of high economy and has moved from a crop of waste lands to commercial crop, even in organized sector (Singh, 1998).

The cashew nut (Anacardium occidentale L.) belongs to Anacardiaceae family which also includes the mango, pistachio and poison ivy (Nakasone and Paull, 1998). Anacardium contains 8 species all of which are native to the coastal parts of north eastern Brazil (Azam-Ali and Judge, 2001). Cashew nut tree provides food, employment, income and the wood is used for carpentry mainly in the construction of boats and ferries while other products derived from it include firewood and charcoal (Akinwale, 2000). Cashew resins are also used in the manufacture of insect repellents and natural insecticides, while different tree parts have medicinal value as they are used to cure various diseases (Cavalcante et al., 2003). The cashew tree is a sprawling broad-leafed evergreen, well adapted to poor soils and dry sandy locations, drought resistant, but grows best on well drained sandy soils with pH of 4.5 to 6.5 (Aliyu, 2004). It favours temperatures between 15 to 35°C and rainfall over 400 mm with elevation of up to 1000 m above sea level.

Cancer cryosurgery began in England during 1850s, when James Arnott used local application of salt solutions containing crushed ice to treat advanced cancers in accessible sites, such as breast and the uterine cervix. Since then, landmark advances in chemistry, physics, material science, and biology have culminated in the sophisticated cryosurgical devices currently in use.
 
Cryosurgery is defined as a method that uses the local application of extreme cold to destroy abnormal or diseased tissue, with the possibility of the maintenance of normal adjacent tissue. Normal tissue can be maintained because the extension of the ice ball can be controlled. Tissue temperature should reach -20^o C or below. Attempts should be taken to kill all tissues in the target with minimal damage to surrounding tissues. There is a variable response of tissues to cryotherapy based on density, vascularity and the water content of the tissue, temperature and size of the cryoprobe, spray rate, rate of freeze, rate of thaw and number of freeze and thaw cycles. It is ideal to have quick freeze and slow thaw for maximum benefit. The extent of freezing should be closely monitored, with either temperature monitoring probes or by visual inspection and palpation of frozen area and this is more advantageous in case of relatively small lesions.

Canine transmissible venereal tumours (CTVT) is also known as infectious sarcoma, transmissible venereal tumours (TVT), venereal granuloma (VG), canine transmissible venereal sarcoma (CTVS), transmissible lymphosarcoma or Sticker tumour, is a benign reticuloendothelial tumour of the dog that mainly affects the external genitalia and occasionally the internal. As it is usually transmitted during coitus it mainly occurs in young, sexually mature animal. Canine transmissible venereal tumour is histocytic tumours that may be transmitted among dogs through coitus, licking, biting and sniffing tumour affected areas. CTVT is spread by the transfer of living cells between dogs, usually during mating. The tumour cells are themselves the infectious agents, and the tumours that form are not genetically related to the host dog (Purohit, 2008; wikipedia ctvt).