Strychnos nux-vomica

Plant profile

Strychnos nux-vomica

Therapeutic uses

• Dried seeds of kuchila are nervine, stomachic, and cardio-tonic, aphrodisiac, and respiratory stimulant.
• It is used as a remedy in chronic dysentery, paralytic and neuralgic disorders, epilepsy, rheumatic arthritis, and hydrophobia.
• In excessive doses, Strychnos is a virulent poison, producing stiffness of muscles and convulsions, ultimately leading to death.
• It is an important drug in all systems of medicine.

Morphological characteristics

• Strychnos species is a medium-sized, deciduous tree, with fairly straight and cylindrical bole and dark-grey or yellowish-grey bark with minute tubercles.
• Leaves are simple, opposite, orbicular to ovate, 6–12 cm long and 6–10 cm broad, coriaceous, glabrous, and five-nerved.

Floral characteristics

• Flowers of kuchila are white or greenish white and fragrant.
• They occur in many flowered terminal cymes.
• Calyx is five lobed, pubescent, and small, about 2 mm in size, while corolla is salver shaped and has five lobes.
• Corolla tube is cylindrical, greenish white inside and slightly hairy near the base. Stamens are five in number and have short filaments.
• Fruit is an indehiscent berry, 5–6 cm in diameter, thick shelled, orange-red when ripe with fleshy pulp.
• Seeds are discoid, compressed, and coin like, concave on one side and convex on the other, and covered with fine grey silky hairs.
• Flowering occurs from March to May and fruits mature up to December.

Distribution

• The species is indigenous to India and is distributed in moist deciduous forests throughout the tropical India.

Strychnos nux-vomica - mature tree

Climate and soil

• The plant can grow well in dry or humid tropical areas of the country.
• It grows over laterite, sandy, and alluvial soils.

Propagation material

• Seeds are the best material for propagation of kuchila plant.
• The collected seeds are dried in the sun after removing the pulp.
• Preferably, fresh seeds should be used.
• The plant can also be propagated through cuttings.

Agro-technique

Nursery technique

Raising propagules

• A nursery of the plant is raised in December or January in climatic conditions of South India.
• Seeds are sown in polybags of size 25 cm × 20 cm, filled with soil, sand, and FYM (farm- yard manure) mixture.
• Seeds are directly sown in the polybags after appropriate pretreatment.
• The polybags are watered regularly so as to keep them moist.
• The seeds germinate in about 20–30 days.
• Sometimes the germination may continue up to 45 days.
• The seedling growth is very slow but roots grow very fast.
• For vegetative propagation, semi-hardwood cuttings can be prepared in early summer and kept under moist conditions after treating with commercially available rooting hormones. Rooting percentage is quite low, often less than 25%.

Propagule rate and pretreatment

• About 1 kg seeds are required to raise 1 hectare of plantation.
• Seeds have low germination rate and fresh seeds of Strychnos nux-vomica lose viability early.
• Germination can be increased by treating the seeds with hot water (50 °C) for 6–12 hours prior to sowing.

Planting in the field

Land preparation and fertilizer application

• The land is ploughed with disc harrow and tillers to achieve a fine tilth and make it weed-free and arable.
• Pits of size 45 cm × 45 cm × 45 cm are dug at a spacing of 5 m × 5 m and refilled with mixture of soil and manure in 1:1 ratio.
• Appropriate quantities of sand may be added if the soil is heavy.
• About 10 kg of well-rotten FYM is applied in each pit at the time of its refilling.

Transplanting and optimum spacing

• In South India, the seedlings are transplanted with the onset of South-west monsoon in May or early June.
• An optimum spacing of 5 m × 5 m is recommended, which gives a stand of 400 trees per hectare.

Intercropping system

• The plant can be grown as a pure crop or herbaceous crops can be grown with it as intercrops after the first year.

Interculture and maintenance practices

• About 10 kg of well-rotten FYM is mixed in the soil during refilling of pits before planting.
• An additional 10 kg manure may again be applied to the soil around the plants during October–November at the time of weeding.
• A total of 20 kg FYM/plant/year in subsequent years results in best growth of plants.
• This is to be applied in two split doses in June–July and September–October.
• Supplementary doses of inorganic fertilizers (NPK [nitrogen, phosphorus, and potassium]) do not lead to any significant additional growth in the young plantations.
• The area around the basin of the plant should be kept weed-free by frequent weeding.
• The interspaces can be kept weed-free by hand weeding or spraying of herbicides like 0.8% paraquat or 0.4% glyphosate.

Irrigation practices

• The crop needs no irrigation during the rainy season and in dry weather; saplings may be irrigated on alternate days, especially in the early years of growth.
• For matured trees, irrigation by ring method around tree base at a distance of 30 cm during summer months is beneficial.

Disease and pest control

• No significant pest or disease is observed on the crop.

Strychnos nux-vomica - two-year-old sapling

Harvest management

Crop maturity and harvesting

• The tree has a long span of life, that is, 50–60 years.
• It takes about 15–20 years for the tree to initiate flowering.
• The seeds are collected December onwards when they mature.
• Fruits can be harvested periodically for many years.

Post-harvest management

• Mature fruits are manually collected and seeds from them are extracted, washed, dried in shade, and stored for trade.

Chemical constituents

• Strychnine and brucine are two most important and toxic alkaloids present in the seeds (0.4% and 0.6%, respectively).
• Other parts of tree have varying percentages of these two alkaloids— 1.7% and 2.8% in root bark, 0.3% and 0.4% in root-wood, 0.9% and 2.1% in stem-bark, 0.5% and 0.01% in stem-wood, and 0.2% and 0.5% in leaves, respectively.

Yield and cost of cultivation

• Considering a crop stand of 400 plants per hectare and average produce range of 50–75 kg of dry seeds per tree per year, a yield of 12–20 tonnes/hectare is estimated from a 20- year old plantation annually.

Source : Agro-techniques of selected medicinal plants