Everything you need to learn about cultivating herbs in India. Learn about how to cultivate: 1. Amaranthus 2. Elephant-Foot Yam 3. Atropa Belladonna 4. Cassia Acutifolia 5. Catharanthus Roses 6. Chrysanthemum Cinerari Folium 7. Digitalis Purpurea 8. Cultivate Duboisia.
Contents:
- How to Cultivate Amaranthus
- How to Cultivate Elephant-Foot Yam
- How to Cultivate Atropa Belladonna
- How to Cultivate How to Cultivate Cassia Acutifolia
- How to Cultivate Catharanthus Roses
- How to Cultivate Chrysanthemum Cinerari Folium
- How to Cultivate Digitalis Purpurea
- How to Cultivate Cultivate Duboisia
1. How to Cultivate Amaranthus:
In the North Indian hills the grain crop is planted at the break of monsoon and in the South Indian hills from April to May. Leafy amaranths are intolerant of water-logged conditions and thrive best on loam. In North India the leafy amaranths are sown from the middle of March to the end of June. In South India, they are sown throughout the year, though Sept-Oct sowings give the maximum yield of edible greens.
The ornamental amaranths are sown during Jan-Feb or June-July. They grow well in the summer and rainy season but growth is better during later seasons. In the hills, sowings can be clone during February and March.
The normal seed rate for amaranths is between 1.1kg and 2.4 kg/ha although for certain types like ‘Co 1’ and ‘A 62’ the seed rate goes as high as 5 and 10 kg/ha, respectively. The seeds should be sown shallow, c 1.5 cm deep either by broadcast or by drilling in lines 22-30cm apart. Grain amaranths are not usually transplanted. In case of leafy as well as ornamental amaranths, seedlings are transplanted to obtain larger plants and higher seed yields.
For the grain crop the first irrigation is given just after broadcasting the seed. Germination starts 5-6 days after the first irrigation. The next irrigation is given after 15-20 days and then at intervals of 10-15 days till the crop is 2.5-3.0 months old. Thereafter no irrigation is given. In all, it requires 6-7 irrigations. The leafy amaranths are irrigated during spring and summer seasons on every 4th or 5th day after cutting.
Weeding and hoeing are done five to six days after the second irrigation. If necessary, weeding is repeated after the third or fourth irrigation. Hoeing reduces the number of irrigations.
No manuring is done to pure crops of grain amaranths. Generally, the leafy amaranths are grown on residual fertility of the previous crop. However, in some places 20-25 cartloads (per hectare) of well-rotten farmyard manure is applied as basal dressing. A mixture to supply 25 kg N, 25 kg P2O5 and 50 kg K2O per hectare may be applied to the soil. Further 25 kg of N may be given after each cutting.
Diseases and Pests:
Albugo bliti (Biv.) Kuntze is a common leaf-spot disease on amaranths. The green semi-looper, Plusia signata Fabr., the stem boring weevil, Hypolixus truncatulus (Boheman) and the leaf-eating caterpillar, Hymenia recurvalis are known to be serious pests on amaranths in South India. Lamprosema (Nacoleia sp.) and Atrcictomorpha crenulata Fabr. also feed on amaranths. Thuricide at the rate of 28 kg/ha effectively controls the pest H. recurvalis. Dusting sodium flucosilicate (1:8) or 5 per cent DDT controls A. crenulata.
2. How to Cultivate Elephant-Foot Yam:
Elephant-foot yam is cultivated in most parts of India, but Gujarat and Maharashtra in western India, and Kerala, Tamil Nadu and Andhra Pradesh in southern India are the chief centres of cultivation. The chief districts cultivating this vegetable are – Bulsar, Baroda, Kaira and Surat in Gujarat; Osmanabad and Pune in Maharashtra; Godavari and Chittoor in Andhra Pradesh; Ramanathapuram, South Arcot and Coimbatore in Tamil Nadu; and all the districts of Kerala.
In Gujarat, the area under cultivation varied between 600 and 900 hectares during 1971-72 to 1973-74, while production of the yams ranged between 21.000 and 31,500 tonnes.
The plant is cultivated as a pure crop in most of the areas but it can be raised as a subsidiary crop in coconut gardens. In Kerala, it is sometimes grown mixed with ginger. Being an exhausting crop, it is not cultivated in the same field more than once in four or five years. No special rotations are followed, but it is usually cultivated after heavily manured crops, like turmeric in Coimbatore, and sugarcane in Godavari. In Ramanathapuram district, it is followed by onions and ragi in a two-year rotation.
Climate:
Elephant-foot yam is mainly a tropical and sub-tropical crop. It requires a well-distributed rainfall or irrigation facilities, and the difference between the maximum and minimum temperatures should not be wide during its growth-period. Though it favours a humid and warm weather, it is not very exacting in its total rainfall requirements.
In certain areas of Gujarat, it grows well under a rainfall of 1,000-1,500 mm, whereas it does equally well at Pune where the rainfall is just c 650 mm but irrigation facilities are available. It requires fairly high temperatures during the emergence of the shoot; cool and dry conditions favour the development of the corms. Continuous rains are harmful during the emergence period, and stagnation of water during any phase of growth is detrimental to the crop.
Soil:
Well-drained and free-working soils, such as loams and sandy loams are best suited for elephant-foot yam. Alluvial soils as found in Gujarat, are also well suited, whereas in very heavy soils the crop suffers heavily from water stagnation. A good crop can be raised on a light soil with heavy manuring and frequent irrigation. It can also be grown on medium black soils of the Deccan with modification in the layout to permit easy drainage.
In South India, red loam is preferred to black, as the keeping quality of the produce from the former is said to be better. The crop is grown on flat beds in the light soils of Gujarat, whereas, in the medium black soils of the Deccan, it is grown on broad ridges. The broad ridge method is particularly suitable for the heavy rainfall areas. The plant requires about four seasons to produce a crop of marketable size when grown from the small tuberous outgrowths on the corm, called buds.
Preparation of Land:
The land is ploughed repeatedly to a good tilth, and the surface soil broken up to a depth of 15-25 cm. About 50 cartloads of farmyard manure and 12 cartloads of wood-ash are applied per hectare and mixed well with the surface layer. In South India, in addition to farmyard manure, sheep are penned, and sometimes decayed rice and varagu straw (Paspalum scrobiculatum Linn.) are applied and incorporated in the soil.
Varieties:
The commercial crop of elephant-foot yam is, probably, a mixture of varieties and clones, which are economically indistinct. Two distinct types are recognized by the cultivators on the basis of the colour of the flesh – red and white, although other types, like purple, pink, violet, yellowish creamy and buff are also met with.
On the basis of the appearance, two types are distinguished – (i) the smooth-surfaced corms, and (ii) the type with daughter corms protruding from the parent corm; the former type causes irritation of the throat but gives more yield, the latter is non-irritating and edible, and fetches better price but gives less yield.
Propagation:
The crop is propagated vegetatively from its corms. Healthy and sound stocks of corms are selected for seed. The corms are kept heaped in shade and covered with rice straw. The heaps are sometimes covered with a plaster of cow-dung and earth in hot places. For the first-year crop, selected tuberous outgrowths or buds of the fourth-year crop are used as planting material.
If more than one sprout is seen on a corm, only the healthiest one is retained in the centre; otherwise each sprout will produce a small, deformed corm which will not find favour in the market.
Corms for the second- year crop are prepared in the same way as for the first-year crop; but corms for raising the third or fourth-year crop need more attention. The second-year crop takes about eight months and produces corms weighing 0.5 or 1.0 kg. The produce of the second year, when planted in the third year, grows to a size of 1.5-4.0 kg at harvest time. The third-year corms are planted for the fourth-year crop which is harvested for marketing.
When grown as a single-year crop, corms of the fourth-year harvest are cut into two or four pieces with one sprout in each, and planted. It has, however, been reported that the yield from such a crop is comparatively lower than the crop raised from the whole corm of the third year.
The crop is usually planted during April-May, though it can be planted upto July at the latest. Crops planted at other seasons do not come up satisfactorily. In alluvial soils, the land is laid out into flat beds of 3.5 m x 2.0 m; whereas in black soils, broad ridges of 6.0-9.0 m x 1.5m are laid out. The first-year crop is planted in small pits made by a weeding hook, but for the second, third and the fourth-year crops bigger pits are made with the help of a spade.
The planting distance varies according to the size of the seed material. The spacing for the first-year planting is 30 cm apart both ways, for the second year 45 cm, for the third year 60cm and for the fourth year 120cm x 60cm on broad ridges in black soils. The pits are made accordingly and well-rotted farmyard manure is spread c 5 cm thick at the bottom of the pit.
Both ammonium sulphate and superphosphate at the rate of 270-360 kg/ha are placed over the manure layer and covered by a 10cm deep layer of loose soil. The sets are planted one for each pit, in this soil layer.
The corms, or the cut-bits of the corms are so placed in the pits that the bud-portion comes into contact with the soil; and then covered with c2.5 cm of soil. Atop the soil layer, a 5 cm thick layer of paddy husk or dry leaves is placed and kept in place by a thin layer of loose soil pressed over it. Sometimes sunn hemp (Crotalaria juncea Linn.) is simultaneously sown as a cover crop for giving shade in the initial stages, and is buried along the ridges to serve as green manure later.
Aftercare:
Germination commences in about ten days and may continue for six weeks depending on the development of rudimentary buds. Well-developed buds sprout immediately, but dormant buds require a long time to sprout. The crop is frequently weeded, and six weedings are generally required. Irrigation is given once a week when there is no rain, the first one being given immediately after planting, and the second, three days after the first.
As the crop matures, lighter irrigations are required till the corms are removed from the soil. Gaps are filled usually in the third and the fourth-year crops, about a month after planting. The fourth-year crop is top- dressed with 88-110 kg/ha of nitrogen in two doses, the first in July and the second in August. The top-dressing could be given either with a cake or with a mixture of cake and ammonium sulphate. Earthing up is done after each top-dressing. Mulching with leaves and straw while earthing up has a beneficial effect on the size of corms and the yield.
Cover Crops:
A large variety of crops, such as cluster bean (Cyamopsis tetragonoloba Taub.), yams (Dioscorea spp.), chillies (Capsicum annuum Linn.), etc., are planted along the water-channels of elephant- foot yam crop to provide shade to the main crop, and prevent damage by the sun’s heat. Sometimes, the final-year crop is grown mixed with ginger and banana. It is also possible to grow groundnut (Arachis hypogea Linn.), methi (Trigonella foenum-graecum Linn.), radish (Raphanus sativus Linn.), and lucerne (Medicago sativa Linn.) as cash or cover crops without affecting the yield of the main crop.
Elephant-foot yam produces two leaves, usually in the fourth year. The leaves emerge at different periods, but are found together from the 3rd to the 5th month. Longer rest period of the seed-sets before planting, and wider spacing of the crop encourage the formation of the second leaf; but the formation of a second leaf has no bearing on increase in yield.
Flowering is occasionally seen in the third or fourth-year crop. It is observed to be more when the harvesting is delayed beyond January under Pune conditions. Plants, which have flowered, continue to grow vegetatively after the flowers are removed. The flowering shoot does not produce seeds under natural conditions, but seeds produced by hand-pollination behave just like small germinating corms, and do not show any dormancy except during Dec-Feb, when the temperature is low. They require storage in a cool dry place; exposure to direct sunlight and to low temperature for long period kills them.
3. How to Cultivate Atropa Belladonna:
At present, belladonna is cultivated in the farms of the Central Institute of Medicinal and Aromatic Plants (CIMAP) in Srinagar district of Jammu & Kashmir, and also to some extent in Chakrata and Seoni and Chaubattia near Ranikhet in Uttar Pradesh. It can be cultivated successfully in the hills of Uttar Pradesh, Assam and West Bengal, and in the Nilgiri hills in South India. Punjab is also considered suitable for its cultivation.
As a winter annual, it can also be cultivated in the plains in the sub-tropical climate of Jammu. The area under cultivation of belladonna varied between 28 and 33 ha in Jammu & Kashmir during the years 1976-77 to 1979-80. The production varied between 13 and 22 tonnes during this period
Recently, belladonna has been grown by tissue culture methods for production of atropine. The excised root tips c 1.0 cm long are grown in aseptic conditions in the laboratory in modified Street and McGregor’s nutrient solution at 28° in the dark. The dry weight of the excised root tips increases steadily with the progress of culture period. The root tips synthesize c 0.45 per cent atropine when cultured on revised Murashige and Skoog’s nutrient medium.
The plants are heterogenous due to cross pollination and there is considerable variation in growth habit and alkaloid content. Treating the seeds with chemical mutagens and radiation increases the variability and widens the scope for increasing the alkaloid content and the herb yield.
The plant can be propagated from seeds or from cuttings of the young shoots or from fleshy rootstocks. Large-scale cultivation is, however, most successful with seeds under tropical conditions. The seeds are very small, brownish black and are obtained by crushing the berries. They show poor germination due to the hard, thick and waxy seed coat, an inhibitor present in the seed coat, and an internal membrane enclosing the rudimentary embryo.
Seeds pre-treated with sulphuric acid, ethyl alcohol or petroleum ether give better germination than the untreated ones, but the plants from treated seeds are stunted and their alkaloid content is only 40 per cent that of the plants from untreated seeds. Treating the seeds with gibberellic acid (40 ppm for 24 hrs) or thiourea (0.5-2.0%) improves germination without affecting the alkaloid content.
Surface sterilization of the seeds by fungicides like Captan, Agrosan GN, Dithane-45 or Agallol before sowing reduces seedling mortality due to damping off. The seeds are sown broadcast or in rows in well prepared nursery beds during May and July at the rate of 4 kg/ha.
In the preparation of nursery beds, use of well decomposed farmyard manure has been found beneficial. When grown as a winter annual, as in Jammu, the seeds are sown in late September. Before sowing, Aldrin is added to the soil to control damage due to cut- worms. The seeds germinate in 10-15 days.
The nurseries are irrigated frequently and are shaded during summer. On germination the seedlings are sprayed with a solution of urea (0.1%) every week till they are ready for transplantation. Insecticides like Thiodan and Sevin are mixed with the spray when required.
The belladonna crop requires a porous, slightly acidic soil rich in mineral nutrients. It does not tolerate waterlogging and requires protection from strong sunlight. When the seedlings are 15-20 cm tall, they are transplanted in raised beds at a spacing of 30 cm x 45 cm or 45 cm x 45 cm. In heavy rainfall areas, planting is done 60cm apart on ridges.
Before transplanting, the soil is ploughed thoroughly and made loose, and a basal dose of 25 kg nitrogen per hectare as calcium ammonium nitrate and 60 kg P2O5 as superphosphate per hectare is applied. Potash is applied as a basal dose of 30 kg as muriate of potash in potash-deficient soils. Organic manure is also mixed with the soil at the rate of 2.5 tonnes/ ha.
The seedlings are transplanted in spring to avoid damage due to winter frost. When grown as a winter annual, they are transplanted in November. Shading the transplants with some pine needles or other twigs is necessary to minimise transpiration losses. Irrigation is required during the dry summer months. After the seedlings are well established, urea is sprayed periodically to provide 30-45 kg/ha of nitrogen during the growing season. The crop grown as winter annuals in the plains of Jammu is top-dressed in February and in April.
The plants require frequent inter-culture to keep the soil loose and to control weeds. The common weeds found with Atropa are Stachys gennanica Linn., Verbascum thapsus Linn., Senecio spp., Phytolacca acinosa Roxb. and Brassica spp. These are eradicated by pulling them out before flowering. Belladonna grows vigorously during summer and rainy seasons. In autumn and winter, the plants start shedding leaves. The sub-terranean parts resume growth with the advent of spring. In the second year the plants start flowering.
Soil and Climate:
Belladonna is a temperate plant and thrives well in deep fertile soils of medium texture, rich in humus. Heavy clay and waterlogged soils are not suitable. In temperate climates like western and central Europe and Kashmir valley in India, the plant behaves as a perennial and gives maximum yield of green herb and alkaloid.
It can also be cultivated as a winter annual crop in sub-tropical areas like northern India, but under such conditions only one crop can be obtained and the plant des away during summer season. Alkaloid content under sub-tropical conditions is poor and the plant does not produce sufficient amount of seeds because of a short life-cycle.
Propagation:
Although, the plant can be propagated vegetatively by root cuttings, the stand is very poor and the system is too costly if applied in commercial farming. However, root cuttings and splits can be used for experimental cultivation. The most economic method of propagation is raising a nursery through seeds and transplanting in the field. Direct sowing has also been adopted in USSR where large areas are under mechanised cultivation.
For raising nursery, the field should be tilled well so as to give a fine tilth. Raised nursery beds should be made and well-rotten farmyard manure or leaf compost should be mixed in the top soil. Seeds should be broadcasted at the surface @ 200 g per sqm and covered with a thin layer of sand and compost. Use of high quality and heavy seed rate is essential to get a good crop stand.
Although, a number of seed treatments like heat and treatment with alcohol and thiourea have been recommended (2,6), experience in India has shown that good germination can be obtained if the seeds are treated with any seed dressing fungicide like Dithane-Z 78 or Captan. The bed should be covered with a layer of mulch of straw or leaf compost. The bed should be irrigated with a sprinkler. The extra mulch should be removed as soon as the seeds sprout.
In temperate areas seedlings are raised in early summer (May- June) or in autumn (September-October). Seedlings are ready for planting in the field after 8-12 weeks. Ideal time for planting is spring or autumn. Generally, seedlings raised in autumn are planted in spring and those raised in summer are planted in autumn. Seedlings should be planted at a distance of 50-60 cm in rows which are 60- 70 cm apart. It is better to plant the seedlings on ridges in order to facilitate irrigation and avoid waterlogging.
Interculture and Weed Control:
Belladonna field should be kept free from weeds by repeated weeding and hoeing. Normally, 3-4 weedings and hoeings are required during the growing season. Interculture can also be carried out by a tractor. However, hand weeding is practicable in hilly areas or small terraces.
Studies in Europe and India have shown that belladonna responds well to fertilizer application. Nitrogenous fertilizers give good response (15). However, application of nitrogen beyond a certain level does not affect alkaloid content. It is always better to give a balanced fertilizer of nitrogen, phosphorus and potash in order to get a good crop.
Normally, a basal dose of 20 kg/ha nitrogen, 60 kg/ha phosphorus and 50 kg/ha potash should be applied before planting. Three top dressings of nitrogen at the rate of 20 kg/ha per application at an interval of six weeks give good results under Indian conditions. This practice should be followed during the first year. 60 Kg/ha nitrogen in 3 split doses should be applied in succeeding years. Trace elements have been found to affect growth.
4. How to Cultivate Cassia Acutifolia:
Soil and Climate:
Senna requires light or medium loam soils with adequate drainage and pH varying from 7.0 to 8.2. Being a native of mediterranean area, it requires mild sub-tropical climate with warm winters which are free from frost. All semi-arid areas with adequate irrigation facilities are ideal for cultivation of this crop. Areas having high rainfall, and humidity and poor drainage are not suitable for this crop. Because of this reason, most of the senna in India is cultivated in semi-arid areas specially in dry lands in Tamil Nadu, where winters are very warm and summer temperatures are not very high and two crops can be taken in a year (1, 3, 5, 7).
Propagation:
Senna is propagated by seed. In south India, both summer and winter crops are planted. The seeds are planted either in October- November (winter rain- fed crop) or in February-March (irrigated crop). The seeds are planted in lines about 30 cm apart. 15-20 Kg seeds per hectare are required depending upon whether it is irrigated or un-irrigated crop. Higher seed rate is required in an un-irrigated crop. (3, 5, 7)
Inter-Culture and Weed Control:
The crop requires 2-3 weedings and hoeings in order to keep it free from weeds.
Fertilizers and Manures:
Farmers in south India generally apply 5-10 tonnes of farmyard manure per hectare before planting, or grow a green manure crop, and no artificial fertilizers are used. However, it has been observed that 40 kg nitrogen, 25-50 kg P2O5 per hectare applied as basal dressing and 40 kg nitrogen per hectare applied in two split doses as top dressing, give better yield. Some workers found no effect of nitrogen on sennoside content, while others reported that nitrogen application increases sennoside content.
Irrigation:
While the rain-fed crop is grown without irrigation, the irrigated crop requires 5-8 light irrigations during the entire growing season.
Harvesting and Processing:
Under irrigated conditions, the first crop is obtained after 90 days of planting. The leaves are stripped by hand when they are fully grown, thick and bluish-green in colour. The second crop is taken four weeks after the first harvest and the third 4-6 weeks after the second harvest. The last crop of leaves is taken when the entire crop is harvested along with the pods. The leaves are dried in thin layers under shade so as to keep the green.
5. How to Cultivate Catharanthus Roses:
Climate and Soil:
The plant is very hard, and grows luxuriantly under a great variety of climatic and soil conditions except the highly alkaline or water-logged soils. It prefers light, well- drained, sandy loam. A mild tropical climate and well-distributed rainfall of 100 cm per annum are sufficient to raise a commercial rain-fed crop.
Preparation of Land:
The land is repeatedly ploughed and brought to a fine tilth, and manured adequately with farmyard manure or compost prior to sowing. Groundnut cake is also applied at some places. Herbicides like 2, 4-D and Gramoxone are mixed in the soil while manuring to prevent infestation by weeds.
Sowing:
The plant can be propagated from seeds or stem cuttings. Fresh seeds (1 kg/ha) are sown with the onset of monsoon in late June, in rows 10-15 cm apart, in small beds and then irrigated immediately. The seeds germinate in about ten days and in 30-45 days develop 2-3 pairs of leaves, and are ready for transplanting. The seeds (2.5 kg/ha) mixed with sand can also be sown directly in the field. In the field, the seedlings are transplanted at a distance of 30 x 45 cm. About 74,000 plants are optimum for a hectare.
Manuring:
The crop responds well to manuring with 80 kg nitrogen/ha in sandy soils; with detopping of plants at 2 cm height, up to 120 kg N/ha can be applied profitably. Split- application of N gives better results. Phosphorus and potash at 40 kg/ha or green manuring and application of micronutrients are recommended. Phosphorus increases the yield of alkaloids in leaves while potassium helps in increasing the yield of alkaloids in roots.
Irrigation:
The plants are drought-resistant and do not require much water. Also, a majority of the growers raise a rain- fed crop during the monsoon season. Light irrigations are required in case of inadequate rains. The irrigated crop requires 5-6 light irrigations. The leaves showed the highest concentration of alkaloids at soil moisture deficit levels in comparison with stems and roots.
Even though partial drought enhances synthesis and production of alkaloids, irrigation induces more of vegetative growth and enhances the yield of roots and foliage and compensates for lower alkaloid content.
Inter-Culture:
The crop is given 2-3 inter-cultures at 20 or 30 days interval. Once the plants cover the field, they smother weed growth. Mulching with rice straw or cut grass is beneficial. At early flowering stage, the top 2 cm portions of the plant are removed to promote vegetative growth and alkaloid content.
Diseases and Pests:
Periwinkle crop is relatively free from damage due to pests and diseases. Termites and other soil-borne insects sometimes infest the growing seedlings. BHC (10%) or Aldrin added to the soil before planting protects the seedlings. Thrips and aphids infest the growing parts, they are killed by sprays of Malathion or BHC. Among viral diseases, the green rosette disease produces an atrophy of all growing parts. A spray of nicotine sulphate (0.5%) is beneficial.
The cucumber mosaic virus causes a severe leaf mosaic; it is also controlled by nicotine sulphate. A little-leaf disease due to MLO (mycoplasma-like organism) was observed in plants growing in Orissa. The leaves and flowers were small and green fruit formation was absent. The disease is transmitted through grafts. Spraying of tetracycline hydrochloride (100 ppm) is beneficial.
A large number of pathogenic fungi are known to infect periwinkle. Of these, Phytophthora parasitica Dastur, Pythium butleri Subram., and Fusarium spp. cause damping-off in seedlings. Periodical spraying of Dithane Z-78 controls them. Tetraploids are found to be resistant to P. butleri. In Lucknow, Alternaria alternata (Fr.) Keissler has been reported to cause severe leaf spot disease during July-August.
Harvesting:
About 150 days after sowing or transplanting, the periwinkle roots penetrate the soil upto 15-25 cm and then develop lateral rootlets. The crop is ready for harvest of roots after one year. During this period, two leaf strippings are obtained and a third when the whole plant is harvested. After the first harvest of leaves, 20 kg N/ha is given to hasten new growth. The harvested leaves are dried in shade and stored in gunny bags.
For harvesting the roots, the aerial parts are cut about 7 cm above ground level, the field irrigated and ploughed, and the roots collected, and washed. The basal stems, upto 10 cm long, are separated from roots and cut into pieces and dried. In North India, the plant takes 260-290 days to produce high total alkaloid content in the roots. The roots are also cut into pieces of 15-25 cm length and dried. On drying, the roots and stems lose 70-80% of their weight. The produce can be stored under normal storage conditions for one or two years.
Yield:
The total yield of plant material consisting of the foliage, basal stems and roots from an irrigated crop in peninsular India is 2.2 tonnes/ha, and in the north Indian plains, 1.8 tonnes/ha. The rain-fed crop yields 1.0-1.5 tonnes/ha.
6. How to Cultivate Chrysanthemum Cinerari Folium:
Climate and Soil:
The plant is grown as a pure crop. In Kashmir, it thrives best in well-drained loamy soils, receiving an annual rainfall of 90-125 cm. Rich and water-logged soils and frost are unsuitable. It can be cultivated between 1,500 and 2,400 m both in Kashmir and in the Nilgiri and Upper Palni and Kodaikanal hills. In South India, the plant tolerates summer heat and winter frost.
For maximum yield of flowers, dormancy during winter is necessary, which, in the tropics may not be possible at an altitude less than 1,830 m. The pyrethrin content was found to be high in the cool mountain valleys where the mean temperature is low. Wherever the conditions of soil are satisfactory, the crop may be planted on hill-slopes. However, these soils require greater fertilization and careful irrigation for yield equal to that received from the level lands.
At high altitudes, where land remains moist, it can be grown as a rain-fed crop. High rainfall adversely affects the growth. In South India, pyrethrum is cultivated in areas where the soil is acidic and annual rainfall is 150-170 cm. In Kodaikanal area where pH of soil ranges between 4.5 and 5.4, it may be adjusted to 6.6-7.5 by liming. This treatment is reported to increase the flower yield. However, it did not increase pyrethrin content of the flower. The plants prefer black loamy volcanic soils with good drainage.
Propagation:
The crop is grown from the seeds. About 40 kg seeds per hectare are required. Seeds stored for more than five years lose their viability and are unsuitable for commercial cultivation. In Kashmir, they are thinly sown in nurseries during Aug.-Sept., lightly covered with sifted soil, and kept moist under temporary shade. High temperature is unfavourable for germination. The seedlings are transplanted in the field in November or early spring when they are about 10-15 cm in height.
Ridge planting is better than flat planting as it facilitates inter-culture and irrigation and avoids water logging. In South India, the seeds are sown (50 g/bed) during March-April in raised nursery-beds of 6.0 m x 1.2 m, prepared by adding forest- litter and completely decomposed farmyard manure.
Germination commences in 8 days and is completed in 15-20 days. Overnight soaking of seeds in 50 ppm gibberellic acid before sowing improves germination. The seedlings are ready for transplanting in 75-90 days during the rainy season.
The splits from mature plants, with desired characters such as high yield, erect and uniform habit, large flowers and uniform and quicker flowering, may also be utilized for planting. The number of splits per plant may be increased by earthing up the plants to encourage the growth of adventitious roots on the young stems.
The plants are spaced at 45 cm x 27 cm in Kashmir. With regular irrigation, yields upto 10 quintal dry flowers per hectare can be obtained which is 4-5 times more than the existing yield.
The crop thrives best and gives better results if irrigated at weekly intervals. Also, when irrigated, the plants flowered earlier. At Kodaikanal, the planting is done during June-July at an optimum spacing of 45 cm x 45 cm on the contours over the terraces. Vegetative multiplication of propagules of choice cultivars is quicker through tissue culture. A procedure for regeneration of pyrethrum plants from callus culture has been developed.
Three culture lines C5, C9 and C10, were established from leaves of clone ‘HSL 801’ on modified MS medium supplemented with 2,4-D and 6-benzylaminopurine. Culture line C, excelled over the other two lines in its regeneration ability. It contained 0.5 per cent pyrethrins per 100g dry wt. of callus tissue. Cultures expressing a high degree of differentiation and organization produce more pyrethrins than those growing as callus tissue. The plant part used to initiate the culture appears to have little influence on pyrethrin production capacity.
Fertilizers:
In Kashmir, c 100 kg nitrogen is applied in April when grown begin new growth. Prior to this, 60 kg phosphorus and potassium each is given at the beginning of the season. On South Indian hills, the crop responds favourably to higher doses of phosphorus at 120 kg/ha compared with nitrogen or potassium. A dose of 45 kg urea, 480kg rock phosphate and 30 kg muriate of potash per hectare per annum is ideal for acidic soils for maximum yield.
Urea may be applied in two doses, half at the time of planting and the rest after three months. Adding lime to the soils also released phosphorus which improves the yield. It has been reported that plants grown in phosphorus deficient soils respond well to mycorrhizal inoculation. At Kodaikanal, inoculation with Glomus fasciculatum, G. caledonius and Gigaspora margarita enhanced the plant height, plant weight, number of branches and root length. The crop is weeded twice, once before flowering and then after harvesting.
Flowering:
The plants need chilling at low temperature to produce good crop of floral buds. A temperature below 16° for 10 days, 3 months after the maximum cold, stimulates maximum flowering. The initiation of flower is inhibited if mean maximum temperature remains at 24° for a week. The transplanted seedlings start flowering after 4-5 months. At Kodaikanal, the plants flower throughout the year with maximum production during summer, whereas in Kashmir, they flower during May-June.
Since pyrethrum is a totally cross- pollinated species, large areas under a single genotype may reduce the overall yield of pyrethrins due to absence of pollinating agent whereby the seed-setting is poor. Hence, planting of a few pollinators is essential for maximum benefits of an improved strain. The studies at RRL, Srinagar, have revealed that pollination increases yield of flower by 11.72 percent, pyrethrins content by 32.31 per cent and the pyrethrins per unit area by 38.44 percent. It is safe to release composite varieties for many-fold advantages accompanying such varieties.
Application of 100 ppm aqueous solution of NNA and IAA to plants is found to increase the yield and the pyrethrins content. Spraying the plants with TIBA (2, 3, 5-Triodobenzoic acid), CCC (2- Chloroethyl trimethyl ammonium chloride) one month after transplanting and continuing it at monthly intervals till flowering gave encouraging results. CCC in general advances flowering by 9 days.
CCC 250 ppm and TIBA 100 ppm recorded higher number of flowers over control. TIBA 100 ppm and CCC 250 ppm are reported to increase fresh and dry weight of flowers and total pyrethrin content.
7. How to Cultivate Digitalis Purpurea:
Digitalis requires medium to light medium soils, rich in organic matter with adequate drainage. It thrives well in slightly acidic to neutral soils. It is a temperate plant and optimum yields are obtained in temperate areas. However, it can also be cultivated in high hills in tropical areas, where temperature do not go above 35°C. It is cultivated as a winter annual crop in sub-tropical areas. However, the yield is low.
Digitalis purpurea is propagated through seeds, which can be directly planted in the field, or a nursery is raised and seedlings are planted when 4-6 weeks old. Direct seeding can be done in March- April, or in October-November in autumn. Seeds are planted in rows at a distance of 4-5 cm and thinned out at a distance of 20- 30 cm, when they are 5-5.7 cm high.
For raising nursery, seeds are generally planted in hothouses in February and then transferred to field in March-April. Seedlings are planted at a distance of 20-30 cm in rows which are 45 cm apart
Interculture and Weed Control:
2-3 weedings and hoeings are adequate during the year in order to keep the crop weed free.
Digitalis responds well to manuring. Both nitrogen and phosphorus fertilizers have been found to increase the yield of both leaves and glycosides. It is advisable to apply ten tonnes well-rotten farmyard manure before planting. Two doses of nitrogen at the rate of 20 kg/hectare can be applied as top dressing. In case no farmyard manure is applied, 30 kg P2O5, 30 kg K2O and 30 kg nitrogen should be applied as basal dose. Three top dressings of 20 kg nitrogen each can be applied throughout the growing season
The Foxglove is cultivated by a few growers in this country in order to provide a drug of uniform activity from a true type of Digitalis purpurea. It is absolutely necessary to have the true medicinal seeds to supply the drug market- crops must be obtained from carefully selected wild seed and all variations from the new type struck out.
The plant will flourish best in well-drained loose soil, preferably of siliceous origin, with some slight shade. The plants growing in sunny situations possess the active qualities of the herb in a much greater degree than those shaded by trees, and it has been proved that those grown on a hot, sunny bank, protected by a wood, give the best results.
It grows best when allowed to seed itself, but if it is desired to raise it by sown seed, 2 lb. of seed to the acre are required. As the seeds are so small and light, they should be mixed with fine sand in order to ensure even distribution. They should be thinly covered with soil. The seeds are uncertain in germination, but the seedlings may be readily and safely transplanted in damp weather, and should be pricked out to 6 to 9 inches apart.
Sown in spring, the plant will not blossom till the following year. Seeds must be gathered as soon as ripe. The flowers of the true medicinal type must be pure, dull pink or magenta, not pale-coloured, white or spotted externally.
It is estimated that one acre of good soil will grow at least two tons of the Foxglove foliage, producing about ½ ton of the dried leaves.
Preparation for Market:
The leaves alone are now used for the extraction of the drug, although formerly the seeds were also official.
No leaves are to be used for medicinal purposes that are not taken from the two-year-old plants, picked when the bloom spike has run up and about two-thirds of the flowers are expanded, because at this time, before the ripening of the seeds, the leaves are in the most active state. They may be collected as long as they are in good condition: only green, perfect leaves being picked, all those that are insect-eaten or diseased, or tinged with purple or otherwise discoloured, must be discarded.
Leaves from seedlings are valueless, and they must also not be collected in the spring, before the plant flowers, or in the autumn, when it has seeded, as the activity of the alkaloids is in each case too low.
If the fresh leaves are sent to the manufacturing druggists for extract-making, they should be in V2 cwt. bundles, packed in air- covered railway cattle-trucks, or if in an open truck, must be covered with tarpaulin. The fresh crop should, if possible, be delivered to the wholesale buyer the same day as cut, but if this is impossible, on account of distance, they should be picked before the dew falls in the late afternoon and dispatched the same evening, packed loosely in wicker baskets, lined with an open kind of muslin.
Consignments by rail should be labeled – “Urgent, Medicinal Herbs,” to ensure quick delivery. The weather for picking must be absolutely dry — no damp or rain in the air and the leaves must be kept out of the sun and not packed too closely, or they may heat and turn yellow.
The odour of the fresh leaves is unpleasant, and the taste of both fresh and dried leaves is disagreeably bitter.
Foxglove leaves have in some places been recklessly gathered by over-zealous and thoughtless collectors without due regard to the future supply of the plants. The plant should not be roughly treated and never cut off just above the root, but the bottom leaves should in all cases be left to nourish the flower-spikes, in order that the seed may be ripened. In patches where Foxgloves grow thickly, the collection and redistribution of seed in likely places is much to be recommended.
The dried leaves as imported have occasionally been found adulterated with the leaves of various other plants. The chief of these are Inula Conyza (Ploughman’s Spikenard), which may be distinguished by their greater roughness, the less-divided margins, the teeth of which have horny points, and odour when rubbed; I. Helenium (Elecampane), the leaves of which resemble Foxglove leaves, though they are less pointed, and the lower lateral veins do not form a ‘wing’ as in the Foxglove; the leaves of Symphytum officinale (Comfrey), which, however, may be recognized by the isolated stiff hairs they bear, and Verbascum Thapsus (Great Mullein), the leaves of which, unlike those of the Foxglove, have woolly upper and under surfaces, and the hairs of which, examined under a lens, are seen to be branched.
Primrose leaves are also sometimes mingled with the drug, though they are much smaller than the average Foxglove leaf, and may be readily distinguished by the straight, lateral veins, which divide near the margins of the leaves. Foxglove leaves are easy to distinguish by their veins running down the leaf.
There is no reason why Foxglove leaves, properly prepared, should not become a national export.
Digitalis has lately been grown in Government Cinchona plantations in the Nilgiris, Madras, in India. The leaves are coarser and rather darker in colour than British or German-grown leaves, wild or cultivated, but tests show that the tincture prepared from them contains glucosides of more than average value.
8. How to Cultivate Duboisia?
A tall glabrous shrub or small tree; flowers, axillary clusters, white with two-lipped calyx; corolla, funnel-shaped; limb, five parted; five stamens within the corolla (two long and two short); one rudimentary ovary, two many-ovalled compartments and fruit berrylike; leaves, inodorous and bitter taste. Another species, Duboisia Hoopwoodii, contains an acrid liquid alkaloid, Piturine, which is said to be identical with nicotine; it is largely used by the natives of Central Australia rather in the same way that the Indians use Coca leaves.
It is obtained from the leaves and twigs, which are collected while the flowers are in bloom in August; the native smoke and chew it for its stimulating effect, which enables them to work at high pressure without food.
Duboisias grow well in mild, cool and dry climates with annual rainfall of 700-1000 mm. Too humid climates with extremes of temperature are not suitable for this crop. Under Indian conditions, Duboisia grows much better in Deccan plateau, mainly in the states of Karnataka and Andhra Pradesh, where both summer and winter temperatures are mild and the rainfall is fairly well distributed and not heavy. As such, semi-arid areas with mild temperatures are ideal for cultivation of this crop.
This tree can grow in a wide range of soils from light loam to heavy clay. However, heavy clay and waterlogged soils should be avoided. Duboisias require good drainage and freedom from frost.
Duboisia can be propagated from root cuttings, terminal shoot cuttings and seeds. However, in commercial plantations, only seeds or terminal shoot cuttings are used in practice. When raising seedlings, seeds are treated with gibberellic acid for 24 hours at 20°C. Seeds are then washed, dried and kept for six weeks before planting (5). Seeds should be planted in a mixture of soil, farmyard manure and compost in polythene bags. These are kept in 60% shade. Seeds are watered regularly. Seeds germinate in 3-4 weeks and seedlings are transplanted when 6-10 weeks old and have a distinct purple pigmentation.
Studies have shown that treatment with gibberellic acid is essential for a good seed germination. It has been observed that gibberellic acid can be substituted by subjecting the seeds to an optimum alternating temperature of 15°C for 5 hours and 30°C for 19 hours.
Seedlings are transplanted at a distance of 3.6 x 8 m or 4.5 x 3.6 m in Australia. In India, narrower spacing gives better results. A spacing of 2 x 2 m has been found to give very good leaf yield. The ideal time for planting the tree is rainy season in India or the fall in Australia. However, in India, it can be planted during the months of February-March also.
Australian experiments have shown that is better to propagate hybrids between Duboisia myoporoides and D. leichardtii by terminal shoot cuttings with 3-4 leaves and treated with a suitable rooting hormone are transplanted in pots, which are kept in a mist chamber (1,2,15)
Inter-Culture and Weed Control:
Young seedlings should be kept free from weeds. It is better to keep inter-row spaces well ploughed up, or raising the intercrop of some legumes to keep the area weed-free. Trifluralin has been used as a pre-planting weedicide and Paraquat has been used when the trees grow to a height of 2 m and above. However, care should be taken not to spray the tree if cork has not been formed.
Detailed fertilizer experiments have not been carried out. However, experiments in India have shown that in order to get good results, 5 kg farmyard manure should be mixed in each pit before planting. It is also advisable to mix in soil 50 g superphosphate and 20 g potash per pit before planting. 20 Kg nitrogen/ha in two split doses at an interval of two months should be used after the plants have grown to a height of 1 m.
Fertilizers should be applied in a ring around the trees. Hydroponic culture experiments have shown that a high dose of nitrogen gave significant increase in growth of plants, but increasing the nitrogen decreased the alkaloid content. However, increasing the potassium concentration resulted in increase in the hyoscine content.
Experiments carried out in commercial plantations have shown that application of fertilizers did not affect the alkaloid content. However, spraying of seaweed extract has been found to increase the alkaloid content in Australia.
The field should be irrigated immediately after planting. Four to six irrigations are required during rain-free season,
First harvest is obtained after 7-10 months of transplanting, depending upon the growth of tree. Successive harvests are obtained after 6-8 months interval in Australia. Under Indian conditions, it has been found that 2-3 harvests can be obtained in a year. Three harvests can be obtained in Karnataka, while only two harvests are obtained under north Indian conditions.
During harvesting, it is better to prune older branches leaving 20-35% leaves for good successive growth. Leaves should be dried in shade and packed in gunny bags. An average yield of 500-800 kg/hectare leaves is obtained in Australia, while yield of over 1000 kg/ha has been recorded in Indian conditions.