Present status and future strategies for walnut industry in India (Jammu & Kashmir)
Authors: Rafiq Ahmad Shah and Parshant Bakshi
Walnut (Juglans regia L), rich in nutritious substances and various microelement, is one of important economic species in the world of family Juglandaceae (Martinez et al., 2010). The genus Juglans L. (Juglandaceae) consist of 7 to 45 species depending on the taxonomic study (Aradhya et al., 2007) .Walnut, Juglans regia, is called by different names in different parts of India. The most common vernacular name for walnut in the region is akhrot, but other names are also known, such as dun in Kashmir and khod in parts of Himachal Pradesh and Uttarakhand. In India, walnut production was earlier confined to Jammu & Kashmir and it appears that it spread to Himachal Pradesh and Uttarakhand states of the country. Some limited variability may also exist in eastern and north-eastern regions, viz., Darjeeling, Sikkim and Arunachal Pradesh. It flourishes in temperate belts h at an altitude of 900-3500 msl. The tree normally grows well in cool climates that is free from frost during spring but does not thrive in areas with hot summers.
The production of a good quality walnut crop is, however, dependent on altitude, temperature fluctuations and humidity/moisture during the main fruit development stage. Frost or snow during flowering destroys young flowers and new shoots, thereby affecting crop production. Walnut productions are light demanding species and are drought tolerant. Normally, an evenly distributed annual rainfall of 760 mm is considered to be optimum for a good quality crop. Walnut plants start flowering in February and continue until April, depending upon the elevation. Flowering occurs earlier at lower elevations. Shell hardening begins in the middle of June, and harvesting starts from the middle of August and continues until the end of October. Fruits are harvested from the trees once the endocarp splits and the first fruit begins to shed. Nuts are collected from the ground between the months of September and October in Jammu & Kashmir. After collecting nuts, these are cleaned, washed and dried by spreading them on sheets or floor. Sometimes in order to improve the appearance of nuts, these are bleached with either alkali or acid solution. Nuts which fall down with their husks intact are generally second-grade. After removal of the husks, cleaning and drying, they are stored and marketed separately to fetch a higher price. Delay in drying causes rapid loss in nut quality and makes walnuts susceptible to the mold. Drying of nuts stabilizes the product's weight and prolongs storage life. Therefore, September-October is found to be the best time for colleting nuts. The best time for collecting bud sticks for grafting is January-February. Walnut production involves fewer losses in pre harvesting and post harvesting stages as compared to other crops such as apple. Walnut is less perishable by nature and easy to handle/transport from one place to another. The walnuts produced at altitudes of 1500 m and above are considered of superior quality, with a light-coloured kernel and a characteristic thin shell. At lower elevations, the kernel usually turns brown because of high temperatures at the time of ripening.
AREA AND DISTRIBUTION
Around 30,800 hectares is under walnut cultivation in the country, with the annual production at 36,000 tonnes (Nainwal et al., 2004). The domestic and external demand has been increasing over the years and is projected to 75,000 tonnes by 2020. Therefore, it is necessary to bring additional area to meet the projected demand. The state of Jammu and Kashmir is the major producer of walnuts in India, infact, the entire quantity of walnuts the country exports is from J&K state. In this northwestern area of the country, walnuts are grown all over the Kashmir valley and the hill regions of Jammu. The most important districts for walnut cultivation are Anantnag, Pulwana, Kupwara, Budgam, Baramulla and Srinagar. In Jammu, the largest areas under walnut cultivation are Doda district, followed by Poonch and Udhampur, with minor quantities grown in Rajouri and Kathua districts. Walnut production is very common is kishtwar district especially in tehsil Chattroo of kishtwar district. The area under overall dry fruits which includes Almond, Pecanut and Walnut is 112400 hectares in Jammu and Kashmir and area under walnut is 95601 hectares which means 85.05% of area under dry fruits is under the cultivation of walnut. In Kashmir region only the area under horticulture is 72431 hectares and under walnut production it is 56721 hectares, thus area under dry fruits is more in Kashmir region than in Jammu region. Among all districts in Kashmir region district Anantnag has highest acreage under walnut cultivation 16524 hectares followed by district Budgam 14562 hectares followed by Pulwama district 10918 hectares. In Jammu region district Poonch has highest area 8306 hectares under cultivation followed by district Doda 6616 hectares. So far as production of walnut is concerned it is mainly cultivated in in Anantnag 16163 hectares followed by district Kupwara 8463 hectares. In Jammu region it is 215 hectares highest in Doda district followed by Kishtwar district 64 hectares. Productivity is higher in Kashmir region than in Jammu division. Productivity of walnut is highest in district Baramulla 4.498863 ton/ha followed by district Kulgam 3.98693 ton/ha in Kashmir region. Productivity is higher in Kashmir region than in Jammu division. It is highest in Doda district 1.663525 ton/ha followed by district reasi 1.647861 tonn/ha in Jammu region. In Ladakh region, Leh has highest productivity of 2.22449 tonn/ha.
NUTRITIONAL AND MEDICINAL USES
Walnuts are rich in proteins, fat, minerals and are concentrated source of energy with high essential unsaturated fatty acids such as the a linoleic acid and omega-6 fatty acid. These contain a good amount of Vitamin B group and are the richest in vitamin B6 among all the nuts (Rana et al., 2007).Walnuts are rich in amino acids (glutamic acid, arginine and leucine) particularly sulfured one-taurine (2-aminoethylsulfonic acid) is important as it is involved in many functions of homeostatic regulation, thermoregulation, anti-aging, nervous conduction and protection against oxidative stress. It is extensively used for cooking oil in tribal areas of the region, with hard-shelled walnuts mostly used for this purpose. Walnut is reported to enhance appetite, promote blood circulation and keep the skin delicate. Walnut bark and nut hulls are used as ingredients in naturopathic remedies. Today walnut and its products are being promoted for treating a variety of skin ailments (ringworm, athlete's foot, jock itch, psoriasis, eczema, wounds) constipation, internal parasites and it has been recommended as a gargle to soothe sore throat.
In rural areas of Jammu and Kashmir, many of families are totally dependent upon the walnut cultivation but due to existence of chain of intermediaries, the producers are not getting their due prices. Not only that walnut production adds to income of poor in rural areas but also that walnuts have been important source of nutrition for the poor. In Jammu and Kashmir farmers earn to the tune of Rs. 20000 to Rs. 50000 annually from horticulture; 60 % of people are in this income bracket. 25% of people earn income in the range of Rs. 150000 to 20000, 10% of people earn Rs. 10000 to 15000. And only 5 % of people derive income ranging from Rs. 5000 to 10000. No single family has income less than 50000. It means majority rural people in Jammu and Kashmir earn income in range of Rs. 15000 to 50000 annually. Although the income of this range may appear very less but keeping in view the overall income of these people and share of income from horticulture, the economic dependence of these people on horticulture can be gauged (Kumar,2015). According to a study, walnut orchard can provide permanent green cover to the soil. The gross return on walnut comes round Rs. 3 lakh per hectare. This is based on the yield of 1500 kg per hectare and farm price of Rs. 200 per kg. After deducting the farm expenses assumed to be 40 percent of the gross return, the net income of the farmer comes to be Rs. 1.80 lakh per hectare. According to the reports the walnuts are selling at more than Rs. 300 a kilogram and the walnut kernels between Rs. 400/ to Rs 500/ kilogram presently in outside mandi. The fruit has excellent flavour and is mainly consumed as a dry fruit. Commercially, it is used for preparation of bakery products, chocolates, ice-creams, oils, confectionary and salad products. Immature fruits of walnut can be utilized for preparing various products like pickles, chutneys, fresh juices and syrups. Shells are used in glue, plastics and for making solutions for cleaning and polishing surfaces. Walnut has both alimentary and industrial uses. Walnut hull is used to dye fabrics for rugs and dresses (Ganie et al., 2013). Old walnut trees are felled with permission and the wood is used for making furniture and exquisite walnut wood carved items. This wood carving is an industry in Kashmir and about 9000 to 10000 people survive because of this activity only. Walnut wood carving items are exported to Europe, America and Gulf.
Most of the trees in Jammu & Kashmir are of seedling origin and no standard variety is generally grown here, though Sheri-e-Kashmir University of Agricultural Sciences and Technology (SKUAST-K) has released two walnut cultivars, Hamadan and Sulaiman, having high yield potential and shelling percentage. Introduction of other varieties like Lake English, Drainovsky and Opex Caulchry have also been found promising. Mainly three varieties of walnuts are grown in the state. These varieties are locally called WONTH, KAGAZI AND BURZUL. The Wonth is a hard Nut to crack and has thick and large outer shell and small kernel. It is mostly sold locally and used for extracting oil. The Kagzi is a better sized walnut and has thin outer shell but thick and good sized inner kernel. one can crack Kagzi in hands only . The inner kernel of the Kagzi variety is white. The Burzul is a medium size variety a little dark and with a little thicker outer shell. The inner kernel is not so white but tasty. This walnut too breaks easily. It is presently acid washed to make it look like Kagzi. The walnuts produced in Jammu usually have a thicker shell and are sold in local markets under the name pahari. On the basis of packaging, the walnuts are divided into two categories, bag and box quality. Thin-shelled kagzi walnuts are usually brought to market in wooden boxes and baskets. Nuts with thicker shells are usually transported in bags. In terms of taste, Kashmir walnuts are considered superior but the variations in the colour and size of the crop are not favourable attributes. In-shell walnuts for export are graded and sold under marketing rules set in 1966. Those of a minimum size of 32 mm, a good cracking rate of over 90 percent and the fewest internal defects are assigned the grade designation of India Super-special. Nuts with a minimum size of 30 mm are designated India-Special and nuts of 24-26 mm are graded India I and India B-grade. Strangely Walnut grading units are mostly located in Jammu wherefrom the Kernel is exported to Europe, America and other countries.
Most plantations are of seedling origin and are in scattered form which produces nuts of variable quality. Because of its breeding characteristics, walnut has formed abundant genetic diversities through a long term evolution under complicated environment (Wu et al., 2000a; Yang, 2005). Breeders over the years have exploited the variation amongst these seedling trees to select superior genotypes with desirable traits. Besides, improved cultivars were introduced from other countries and after evaluation, some recommendations have been made. On the whole, walnut has remained a low priority crop in otherwise apple dominated regions.
An ideal walnut variety must have late leafing, both terminal and lateral bearing, low incidence of pistillate flower abscission, high yielding nuts (>6 MT/ha) with jambo size, relatively smooth, >50% kernel recovery, plump and light coloured kernel and at least moderately resistant to pest and diseases (Botu et al., 2010; Cosmulescu et al., 2010; McGranahan and Leslie, 2012).Scientists from different parts of world have practiced simple selection in the natural seed population and selected trees of high nut quality (Germain, 1997; Sharma and Das, 2003; Cosmulescu and Botu, 2012).
Due to poor profitability of traditional crops, people are now shifting towards cultivation of horticulture crops as these crops has helped many of the people to come out of poverty and educate their children. Among horticulture crops walnut is very important as cultivation of walnut requires less skill and more of protection and safeguards? of crops and plants. The walnuts are drought tolerant and can be cultivated even if proper irrigation is not available although the amount of irrigation has an impact on the productivity of walnut. Presently production of walnut in India is around 1.2 tonnes per hectare which is very low in comparison to 3-5 tonne/hectare in advanced countries. India exports 2,665.87 MT walnut to more than 40 nations with earnings of more than 136.45 crores of foreign exchange annually. The top importers of Indian walnut include Egypt, UK, China, Germany, France, Netherlands, UAE, Greece, US, Kuwait, Australia, Hong Kong and Spain.
Indian walnut consumption in 2014-15 is expected to grow eight percent to 28,000 MT due to stable supplies and strong domestic demand. Presently, an estimated 50 to 60 percent of Indian walnut supplies are consumed domestically, of which nearly half are consumed during the festive season. Industry sources estimate that upwards of 10 percent of domestic consumption is by the bakery, confectionary, and ice cream industries. An additional three to four percent of walnuts (typically nuts that are already rancid) are used by soap and cosmetic manufacturers, who extract the oil for use in their various products.
Due to growing domestic consumption, coupled with a decline in domestic production, exports of Indian walnuts decreases. Additionally, tighter domestic supplies encouraged walnut imports, which are forecast at 1,000 MT. As the United States is the only country which currently meets India's quarantine requirements, U.S. walnuts are likely to be exclusively imported. Walnuts are imported into India without quantitative restrictions under the Open General License (OGL) program. Imports are subject to an effective import duty of 30.9 percent except for imports originating from the South Asian Association for Regional Cooperation (SAARC) countries and Afghanistan. Earlier, most of the walnut growing areas were either remote or tribal, and marketing was difficult. Now, with the availability of better communications and road networks, marketing to cities can be done easily. Walnut is a nonperishable commodity and has good storability. It can therefore be transported easily to distant places, including for export.
Significant increases in walnut production can be expected in Jammu & Kashmir where local selections and new cultivars are being evaluated which will require expanded market development. Those engaged in production research must become more closely aligned with the processing and marketing industry to ensure that the quality aspects of walnuts are considered in relation to commercial demand and processing technology. Crop improvement related to higher yield, high number of fruitful lateral, precocity, late leafing, early harvesting, reduce tree size, self-fertile and homogamy are desired. Which is difficult through breeding process and will take long time for achieving the desired results. Therefore researchers are exploiting the local genepool for walnut improvement through selection. Smooth shell texture, light colour, round to oblong in shape, paper shell, strong shell seal, high kernel-shell ratio, plump, bold, easy to remove kernel halves, light in colour, sweet in taste, well filled kernels are some of the good chracteristics for walnut improvement, to boost the export of produce and compete in the international market. Central Institute of Temperate Horticulture, J&K has developed different varieties among these promising one are CITH Walnut 1, CITH Walnut 2, CITH Walnut 3, CITH Walnut 4, CITH Walnut 5, CITH Walnut 6, CITH Walnut 7, CITH Walnut 8, CITH Walnut 9, CITH Walnut 10. Similarly SKUAST- K Shalimar, Kashmir, Srinagar has also recently released two selections Hamdan, Sulaiman. These promising varieties has revolutionized the walnut production in Jammu and Kashmir. These varieties can compete in the national and international market.
Latest techniques of walnut budding/grafting have been introduced which have helped in reducing gestation period of this crop. With assistance of APEDA, a Hi-Tech Green House has been set up at different locations at Jammu & Kashmir which is being used for raising budded/grafted walnuts. Walnut cultivation plays a significant role in the economic profile of the farmers living in hilly and backward areas, where economic condition of the people is extremely fragile.
Walnut growing suffers from lack of suitable methods of propagation, inadequate vegetatively propagated plants, lack of standard rootstocks/ cultivars, problems of re-establishment of nursery plant in the orchard, specific climatic requirements, pollination behaviour and lack of suitable pollinizers, long juvenile period and harvesting. Long gestation periods, poor orchard management, and uneven yields (estimated at 18-50 kg/tree/year with nut sizes varying from 24-32 mm) keep walnut production relatively stagnant.
While conducting the fieldwork for study of genetic diversity of walnut growing areas of Jammu, it was observed that the naturally occurring populations are declining at a fast rate, with few new plantations of known genotype. Cutting of walnut trees for timber and furniture is very common. In Kashmir, walnut is highly valued for making furniture and considerable quantities of wood are being cut and smuggled for this purpose. The trees producing hard shelled nuts are under more threat than thin shelled types because the returns earned after cutting one full grown tree for timber purpose are much higher than income obtained through collection and sale of nuts (over a period of 15 to 20 years). Low productivity due to lack of high quality planting material, poor pollination, low tree density per unit area, predominant terminal bearing, long juvenile period, big tree size, poor filling, poor success rate of grafting, and climatic fluctuations were found to be responsible for limited initiatives for replanting walnut. Seedling derived walnuts commence fruiting at the age of 10 to 15 years, but economic production only commences once trees are quite old (20 to 25 years). Therefore, farmers do not get any income during the non fruiting years. Poor regeneration is also found due to excessive collection of nuts. Further, walnut oil is also used for cooking and people used traditional methods for oil extraction. Therefore even hard shelled nuts are not left to regenerate rather they are preferred for this purpose. Thin shelled nuts were also found to be damaged by birds and monkeys at a premature stage. Birds in these areas make a hole with their long beak and eat away the kernel, without even detaching the nut from the tree. In some areas, farmers are reluctant to share germplasm of good nut morphotypes. Some of the farmers in Dachan and Marwah have very good quality walnut trees in their cultivated lands, but refused to supply walnut samples and bud sticks to the programme for walnut, even when offered payment. People of kishtwar district are predominately engaged in agriculture and walnut production but to lack of proper irrigation facilities and also due to uneconomical holdings the productivity of crops is very low. Walnut in hilly areas are of J&K is mainly concentrated in rural areas where the large majority of under privileged groups and poor farmers. Walnut production has been an important source of income to these people. These borrow money from village money lenders. These people also take goods from the nearby retailers and repay them in time of harvest in the form of walnut produce. By taking advantage of abject poverty of these masses, money lenders and retailers buy these walnuts at fewer prices than they should in view of the market trend. Whatever is produced is not even sufficient to meet their own needs. Apart from these, there are several post-harvest problems in this sector. Constraints in walnut trade include awareness of maturity indices, method of harvesting and non-scientific dehulling.
• Lack of storage facility, drying, grading practices
• Lack of awareness about hygienic protocols condition to handle nuts
• Lack of integrated handling system to manage the nuts
• Non-adoption of international standards on grades
• Lack of processing, storage and orchard management facilities
• Increased competition from overseas suppliers
• External competition from California, Mexico, China and other countries which are competing with India especially in the EU market
India at present lags behind China and the United States in walnut production, "Unlike apple orchards, growers don't have regular walnut orchards in Jammu & Kashmir. Scientists at Jammu and Kashmir's agriculture universities are working to make India one among world's top walnut producers. They believe that once the Jammu & Kashmir will have regular walnut orchards on the pattern of apple orchards, the production will increase manifold within five years. On the advice of the agriculture universities of Jammu & Kashmir the growers have begun developing walnut orchards along the lines of those in the United States, China and other countries. With most trees being 100 to 150 years old, the Agriculture University along with the state's Horticulture department is also encouraging fresh walnut plantation.
The Jammu & Kashmir have vast scope of expansion of area under walnut by establishing regular orchards like apple, by providing farmers good quality disease free planting material, by establishing nurseries and mother orchards of lateral bearing high yielding varieties. The walnut growers also have to come forward united in a form of walnut grower associations to formulate strategy with government to get incentives under some scheme or mission. The cultivation and production of walnut will certainly improve the nutrition status, employment and economy of the rural farmers of Jammu & Kashmir.To bring more area under walnut cultivation in cluster mode, state should adopt end-to-end approach involving production, protection, post harvest management, processing and marketing. To achieve this goal, the Pomology Department of SKUAST-K has started distributing thousands of hybrid grafted walnut plants among the growers. "Besides, distribution of walnut plants, they also provide technical assistance to the growers. So far saplings of Hamdan and Suleiman varieties have been distributed among the growers. Scientists claim that the Hamdan and Suleiman varieties are better in quality than Chandlar, Serr, Tutle varieties grown in the United States.
In Jammu & Kashmir the seedling populations exhibit tremendous genetic variation in tree and phenological traits, colour, shell sealing and in hardness of nuts as well as quality and percentage of kernel. The endemic walnut varieties contain many agronomically excellent properties and specific valuable genes, such as for high content of protein, and strong disease and drought resistances, which have significant potential value for walnut variety improvement (Sharma and Kumar., 1994). Therefore, systematic evaluation of this genetically diverse germplasm needs to be taken up immediately for selecting superior genotypes to build gene repository. Fortunately the selection for most of the traits, being highly heritable, can be accomplished easily. However, in the past decade, under long-term biological or environmental pressure, the walnut resources have been seriously damaged, which may result in increased homogeneity or reduction of genetic variability. The lack of systematic studies of genetic diversity among Juglans species and ecotypes could seriously restrict genetic improvement by limiting exploitation in walnut culture and breeding of many excellent traits found in these landrace lines. Accordingly, it is essential to properly characterize and assess the genetic diversity of landrace walnut resources for protection and breeding utilization.
Walnut collections made in these regions may hold significant opportunities for obtaining germplasm with desirable traits such as improved cold hardiness, pest and disease resistance, stress tolerance, and palatability, which through breeding could lead to the development of productive cultivars adapted to a much wider geographic and climatic area. For example, millions of walnut trees grow wild in the montane fruit forests of Central Asia. Some exceptionally cold hardy plants have been identified there that produce large, thin-shelled, high-quality nuts. Other selections have been identified that express traits such as repeat bloom, the production of nuts on lateral spurs, highly precocious seedlings (also called "fast- fruiting" trees, which produce flowers one or two year from planting the seed, as well as producing grape-like clusters of nuts on the trees), extremely thin shells, apomictic (clonal) seed development, and resistance to numerous pests and diseases (Mamadjanov, 2006). Breeding new walnut varieties through hybridization is both difficult and time consuming. It is therefore, convenient to exploit existing variability by making appropriate selections based on characters like climatic adaptations, precocity, high productivity, good quality of nut and kernel and resistance to major diseases. Anthracnose disease affect all leaves , leaf petioles, shoots, nuts and peduncles , and has been reported to infect several cultivars of English (J. regia L.) as well as black (J. nigra L.) walnuts severely ( Michailides et al., 2012).
Because Jammu & Kashmir has suitable agroclimatic conditions and land where high quality walnuts can be grown. Varieties having desirable traits were formerly not easily available, reflecting the limited breeding work, even at the global level. But now many varieties having desirable traits, like dwarf stature, shorter juvenile period, earliness, better nut: kernel ratio and lateral bearing, are available, and these can be used as planting material instead of seedling trees, which generally are lacking in such desirable traits. Jammu and Kashmir government proposes to set up a Walnut Board in the State to give a boost to walnut production in a big way on scientific lines by setting up scientific walnut processing units in various areas of the State. But still more needs to be done. Right now need of the hour is to open up high technology poly-houses to increase the production, popularize dwarf varieties and introduce high-yielding strains/varieties. This will ensure economic growth of the State in general and farming community in particular as horticulture is the backbone of the State's economy. The close coordination between Horticulture Department and Agriculture Universities of Jammu & Kashmir is imperative so that maximum farmers are benefited. Training for technology transfer is an important component to provide knowledge about the latest developments in the walnut industry through visits to advanced nurseries, walnut farms, walnut manufacturers and government research institutions involved in walnut study programmes. Although walnuts are grown in rain fed areas, the irrigation assumes importance whenever rainfall is deficient. The walnuts grown in draught condition are of poor quality and kernels are yellowish in color. Hence people and government specifically should pay added attention towards the development of irrigation system for the irrigation of walnut trees. Some other steps to be taken are:-
• Promotion of nurseries in private sector to fulfill the huge demand of grafted plants of walnut.
• Introduction of new and improved and high yielding lateral bearing varieties having quality kernels for getting good economic returns to the farmers.
• Linking of Institutions and Universities would be a great help support in this direction. The Central Institution of Temperate Horticulture (CITH) is one of best institution working on walnut and other fruit crops.
• Promotion of drip irrigation system in the walnut orchards to increase the yield and improve the nut quality.
• Dissemination of latest production technology among walnut growers through distribution of package and Practices
• Training and skill up-gradation of nursery men on efficient methods and providing those facilities for vegetative propagation.
• Rejuvenation of old and sick walnut orchards
• Standardization of vegetative propagation techniques of walnuts.
• Establishment of walnut processing units consisting of pre-cooling and storage facilities
• Create technical awareness among farmers for plantation of walnut
• The pests cause lot of damage to walnut produce. More than 2% of total and sometimes even 5% is lost by way of pests.
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About Author / Additional Info:
I am Ph.D scholar at SKUAST-J and working on walnut and also worked as SRF on introduction and evaluation of different temperate fruit crops in Jammu region of Jammu and kashmir