Derris (PROSEA)

Plant Resources of South-East Asia
Introduction

Protologue: Fl. cochinch.: 432 (1790).

Family: Leguminosae

Chromosome number: x= 10, 11, 12, 13; D. acuminata: 2n= 22, D. elegans: 2n= 22, D. elliptica: 2n= 20, 22, 24, 36, D. malaccensis: 2n= 22, 24, D. robusta: n= 11, D. scandens: 2n= 26, D. trifoliata: n= 10, 11, 2n= 22, 24

Major species

Derris elliptica (Wallich) Benth.,
D. malaccensis (Benth.) Prain,
D. trifoliata Lour.

Vernacular names

Derris, tuba root (En).
Touba (Fr)
Indonesia: tuba
Malaysia: tuba
Philippines: tubli
Vietnam: cóc kèn.

Origin and geographic distribution

Derris consists of about 55 species found throughout the Old World tropics. Most species (approximately 50) are found in South-East Asia, 3 in Australia and one species extends from Asia to eastern Africa. D. elliptica and D. malaccensis are cultivated, e.g. in India, southern China, Malaysia, Indonesia, the Philippines, New Guinea, tropical Africa and America.

Uses

The rotenoids from Derris constitute an effective alternative to regular synthetic insecticide applications in horticulture and agriculture. They can be applied to control a large array of pests on a range of crops. The insecticide is applied as dust, spray, dip or bait. In cabbage it is used to control the lepidopterous Plutella xylostella (diamondback moth) and Pieris rapae. It is also used to control the aphid Myzus persicae, which is a major pest of vegetables and peaches in China. Furthermore, it is applied against borers, thrips and seedling maggots on maize, golden apple snails (Pomacea spp.) on rice, against the tenthredinid Caliroa cerasi on apple and oriental pear (Pyrus pyrifolia (N.L. Burman) Nakai), against cotton stainer, black bean aphids, common cutworm, earcutting caterpillar, and against Helluta undalis on broccoli. The extract is also effective against pests of stored garlic and rice. In poultry farming it can be used to kill ticks, fleas, lice, mites, flies and to control sticktight fleas. It is reported to be ineffective against bedbugs, cockroaches, scale insects and red spiders.

D. elliptica and D. malaccensis are used as a fish poison throughout southern Asia and the Pacific. The pounded root is considered the strongest fish poison in South-East Asia. Rotenone is used in fisheries in the Philippines, Bangladesh and India to remove predatory and other undesired fish from rearing ponds.

D. elliptica is traditionally used for antisepsis and applied to abscesses and against leprosy and itch, and sometimes as an abortifacient. The root of D. scandens is used in India to increase milk secretion after childbirth; it is crushed with or without water and the juice is given orally. The whole plant of D. trifoliata is used in India as a stimulant, anti-spasmodic and counter-irritant, and the bark against rheumatism, chronic paralysis and dysmenorrhoea, and in Papua New Guinea a decoction of the roots is applied externally against fever and internally against sores. A solution of crushed leaves of D. elegans is used to wash snake bites in Papua New Guinea. An extract from the roots of D. elliptica is reported to be employed as an ingredient of arrow poison in Borneo.

The stems are sometimes used for rough cordage. The wood of D. robusta trees is sometimes used for tea chests and implements. Derris can serve as soil improver. Lianas, including D. elliptica, may occur as weeds in forest plantations of Acacia, Eucalyptus and Swietenia.

Production and international trade

Until 1930 in Indonesia, Derris was grown as single plants near houses only. Cultivation of Derris was forbidden by law, to prevent fish being eradicated by too intensive use of the roots. Around 1930, several plantation companies planned to cultivate Derris on a large scale, to produce a pesticide for use on crops where the residues of synthetic insecticides could be harmful to the consumer. Within a few years Derris became an estate crop from what was practically a wild plant. In Java and Sumatra the area planted with Derris increased from 240 ha in 1935 to 10 000 ha in 1941. By 1947, however, no regular plantations remained, since everything had been harvested during the war and no new plantations had been established.

The main producing countries in South-East Asia are Malaysia, Indonesia and the Philippines. Imports in the United States of rotenoid-containing roots, mainly from Derris, exceeded 3000 t annually in the early 1950s, and in 1963 about 1500 t of crude Derris roots and 500 t of extract were imported. The introduction of synthetic insecticides, including pyrethrin analogues, has markedly reduced the demand for plant-based insecticides over the last 40-50 years.

Properties

The roots are flexible and hard, with a slightly aromatic odour and somewhat bitter taste. Chemically, Derris species are characterized by the presence of toxic rotenoid compounds; rotenone as isoflavone derivative (0.3-12% in the root) is the most toxic compound, followed by deguelin (0.2-2.9%), elliptone (0.4-4.6%) and toxicarol (0-4.4%). These compounds are effective respiratory poisons; rotenone is a powerful mitochondrial inhibitor of electron transport. It exhibits a considerable degree of selective toxicity; it is very toxic to insects but only slightly toxic to mammals. Derris preparations are comparatively safe to natural enemies (parasites and predators) being used to control insect pests on crops, since they deteriorate when exposed to sunlight and air. To be effective they should contain not less than 3% rotenone on a dry-weight basis.

Compounds related to rotenone, but lacking the core B-C ring system have been synthesized. They are less active than rotenone, but often still have significant levels of inhibition.

The addition of soap solution (0.1%) lowers the toxic concentration of an aqueous extract of roots for snails from 2000 ppm to 100 ppm. Ethanolic and chloroform extracts cause 100% mortality at 100 ppm and 20 ppm, respectively. An ethanolic extract is more toxic than an aqueous extract because this solvent can extract more toxic constituents from the roots. However, this is not practical for use by farmers. Besides, the ethanolic extract is very toxic to fish. Rotenone at 20 ppm causes 83% and 100% mortality in snails after 24 hours and 48 hours, respectively. Rotenone-free extracts of D. elliptica, obtained by chloroform extraction and thermal heating were found to be still toxic to snails, but not to fish.

Studies have been performed with cultured cells in order to more fully characterize the bioactive potential of rotenone. Intense cytotoxic activity was observed in lymphocytic leukaemia, carcinoma of the nasopharynx, and a number of human cancer cells, e.g. fibrosarcoma, lung cancer, colon cancer, melanoma and breast cancer cell lines. Thus, rotenone has been evaluated as a potential antitumour agent. The growth-inhibiting effect has been demonstrated both with cultured cells and experimental tumours. Rotenone is broadly cytotoxic, but no cell-type specificity has been discerned.

Numerous other compounds have also been isolated and identified, e.g. flavonoids, deguelin and maackiain. For instance, roots of D. elliptica contain the rotenoid elliptinol and tubaic acid (0.01% of air-dried root). The latter compound showed anti-microbial activity, inhibiting the growth of Bacillus subtilis, Staphylococcus aureus and Escherichia coli at high concentrations. Other tests, however, showed no antibacterial activity of D. elliptica decoctions or macerations. Several amino acids (e.g. related to pipecolic acid) have been isolated from its leaves, and also the amino-alcohol 2,5-dihydroxymethyl-3,4-dihydroxypyrrolidine (0.1% of fresh leaves). Compounds with a pyrrolidine ring structure might be of pharmacological interest, since some of them are known to have adrenolytic and vasodilating properties. Other related compounds have been found to possess antibacterial activity.

Nine pure compounds have been isolated from the roots of D. robusta: 4 isoflavones and 5 3-phenyl-4-hydroxycoumarins. The isoflavones include derrubone, robustone and robustone methyl-ether; the 3-phenyl-4-hydroxycoumarins include robustic acid and robustin. Seven pure compounds have been isolated from the stems of D. scandens, e.g. the prenylated isoflavones warangalone, 8-γ,γ-dimethylallylwighteone and 3'-γ,γ-dimethylallylwighteone, and the 3-phenyl-4-hydroxycoumarin robustic acid. All the prenylated isoflavones and robustic acid were found to be potent inhibitors of the catalytic subunit of cyclic AMP-dependent protein kinase (cAK, from rat liver, in vitro). None of the compounds, however, was able to inhibit Ca²⁺ dependent and phospholipid-dependent protein kinase C (PKC, from rat brain, in vitro). The flavonoid compound dehydrorotenone, lupeol and a straight-chain ketone have been isolated from the roots of D. trifoliata, but these compounds seem to have no appreciable insecticidal activity. Pentacyclic triterpenoids have also been isolated, whereas the leaves of D. trifoliata have yielded the flavonoid rhamnetin 3-0-neohesperidoside. Fresh leaves of D. trifoliata contain 25 mg/g of lipid, 3 mg/g sterol and 3 mg/g triterpene. The sterol fraction consists of 1.5% cholesterol, 7.5% campesterol, 9% stigmasterol, 21.5% sitosterol and 60.5% stigmast-7-en-3β-ol, the triterpene fraction of 10% β-amyrin, 12% α-amyrin and 78% lupeol. The bark contains up to 9.5% tannin. Seeds of D. robusta contain the pyranoisoflavone derrone, the isoflavones derrugenin, robustigenin and 5-hydroxy-7-methoxyisoflavone, and rubone, a chalcone.

Aqueous extract of fruits of D. trifoliata with an LC₅₀ value of 0.002-0.003 ppt showed toxicity to fish. The LC₅₀ value for roots of D. elliptica for catfish in Bangladesh was 64-115 ppm. The toxicant in the root powder had completely detoxified in 6-7 days. Root powder is effective for eradicating predatory fishes in fish ponds at 5 ppm in fresh water and at 10-30 ppm in brackish water. Derris extract also has some fungicidal activity. The leaves of D. elliptica are said to be poisonous enough to kill cattle.

The wood of D. robusta is pale brown, with heartwood not distinctly demarcated from the sapwood. It is hard and heavy; the density is about 850 kg/m³ at 15% moisture content.

Adulterations and substitutes

Rotenoids are also obtained from the roots of other legumes such as Lonchocarpus, Millettia, Piscidia and Tephrosia spp. Other insecticides of plant origin used in South-East Asia are present in seeds of Croton tiglium L., stem and roots of Tinospora spp., leaves of Vitex negundo L., Nicotiana tabacum L. and Azadirachta indica A.H.L. Juss. They are also found in leaves, fruits and bark of Melia azedarach L., whole plants of Tanacetum cinerariifolium (Trev.) Schultz-Bip., Tagetes spp. and Lantana spp., and in leaves, roots and seeds of Annona squamosa L. As a fungicide, star anise (Illicium verum Hook.f.) is more effective. Other piscicidal plants include Croton tiglium, Myrica esculenta Buch.-Ham. and Sapindus saponaria L.

Description

Woody climbers or scandent shrubs, or sometimes trees (D. robusta) or erect shrubs; roots up to more than 2 m long and up to 2 cm in diameter, dark reddish-brown or greyish-brown; stem of lianas up to 20 m long and up to 10 cm in diameter, often ridged and densely lenticellate.
Leaves alternate, imparipinnate with opposite leaflets, stipules small, stipels sometimes present.
Inflorescence terminal or axillary, pseudoracemose or pseudopaniculate, sometimes contracted, with flowers crowded on the short ultimate branchlets or clustered at the nodes.
Flowers bisexual, 5-merous; calyx tube usually cupular, almost toothless or with short teeth, the upper pair variably joined; corolla papilionaceous, much longer than the calyx, white, pink or purplish, standard often green at base, glabrous or hairy, wings adhering to the keel petals; stamens 10, united into a tube with openings at the base on either side of the upper filament; ovary superior, 1-loculate, with few ovules, style curved and tapering to a very small stigma.
Fruit an oval or elliptical to linear-oblong, flattened, indehiscent pod with wings along upper edge or both edges, 1-few-seeded.
Seeds usually reniform, smooth or wrinkled.

Growth and development

Derris lianas may climb over trees and other vegetation forming a thick cover and thus act as a serious weed in forest plantations. D. elliptica may start flowering at 18 months of age. Wild plants flower and fruit normally. Pods ripen about 4 months after fertilization. The roots form nitrogen-fixing nodules. In cultivation fruiting is rare. Some cultivars like "Ngawi" flower very rarely; others (e.g. "Wulung" and "Pantu") flower freely but seldom fruit.

Other botanical information

Derris is placed in the tribe Millettieae within the subfamily Papilionoideae. It seems closely related to Millettia and Lonchocarpus, and to Aganope (or Ostryocarpus when this originally African genus is considered as congeneric). It is characterized by the winged sutures of the pods. The genus is often subdivided into 3 sections: section Derris with about 50 species including D. elegans and D. trifoliolata, section Brachypterum (Wight & Arn.) Benth. with 3 species including D. robusta and D. scandens, and section Paraderris Miq. with 6 species including D. elliptica and D. malaccensis. The latter two sections have been raised to generic level, differing from the first one particularly in the inflorescences and in the pods. However, new combinations for the Derris species involved have often not yet been made. Sometimes, a fourth section Dipteroderris Benth. is separated from section Derris. The 4 South American species closely related to Derris are usually classified in Deguelia.

Several other Derris species not discussed above have been mentioned as a fish poison and are occasionally used as an insecticide: D. acuminata Benth. (synonym: D. pubipetala Miq.), D. multiflora Benth. and D. montana Benth. for Indonesia, D. philippinensis Merr. for the Philippines, and D. amoena Benth. and D. polyantha Perk. for Peninsular Malaysia. D. ferruginea (Roxb.) Benth. is used in India as an insecticide.

Several cultivars of D. elliptica have been selected of which "Sarawak Creeping", "Changi No 3" and "Ngawi" are reportedly commercially superior. Other cultivars include "Pantu", "Wulung", "Putih" and "Kotari". They differ mainly in hairiness and leaflet shape, but also in rotenoid content, yield and susceptibility to diseases. "Sarawak Erect" has been reported as the D. malaccensis cultivar with the highest content of rotenoids.

Ecology

Derris grows best in regions with an annual precipitation of 2300-3300 mm and a mean annual temperature of 29 °C. D. elliptica can survive dry periods of up to 4 months. This species is often confined to low altitudes, but locally (e.g. in Java) it can be found up to 1500 m altitude. Derris can be grown on a range of soils varying from coarse sand to heavy clay, but swampy and stony soils are unsuitable. Derris is sensitive to waterlogging. It prefers a rich friable loam and tolerates a pH 4.3-8. It is often found on river banks, in brushwood, forest borders and secondary forest. D. trifoliata occurs near the coast in or near mangroves.

Propagation and planting

Ripe dry seeds cannot be stored for long without losing their viability. They germinate immediately after sowing. For commercial production, however, woody stem cuttings 30-45 cm long and 0.5-1.5 cm in diameter and with 3 or more buds are used. In tests in Central America cuttings from mature stems with a diameter of 2 cm and a length of 20-30 cm with at least 2 nodes gave the best results in rooting. Single-node cuttings can be employed if treated with root-inducing substances such as naphthalene acetic acid (0.2%). The cuttings are often first planted in nursery beds, to a depth of 15-20 cm. Shading and regular watering are needed during the dry season, and during the first weeks the beds should be kept free from weeds. When cuttings have 2 normal leaves, the shade is gradually removed. The cuttings are ready for transplanting into the field when about 6 weeks old, and are preferably transplanted in the rainy season. They are planted either in furrows 10 cm deep or in separate planting holes. The planting distance is 0.7-1 m × 0.7-1 m. Direct planting into the field is sometimes also practised, and should also be done in the rainy season. In Indonesia, Tephrosia noctiflora Bojer ex Baker is sometimes used as a shade during the first year, then pulled out and applied as a soil cover.

When planted specially for the production of cuttings, Derris is trained on a fence. Each year, these plantations produce enough material to plant an area at least ten times larger. The area to be planted can easily be enlarged at harvest by using cuttings from the branches of an established plantation.

In tests in the Philippines, tissue culture of D. elliptica was found to be not viable due to low explant decontamination, retarded shoot regeneration for alcohol propagation and unsuccessful shoot regeneration from calli.

In vitro production of active compounds

Tissue culture to obtain rotenoids appears to be rather difficult. When leaves of D. elliptica were used for callus induction, only trace amounts of rotenoids (3 μg/g on dry weight basis) were detected in the tissue subcultured for 4 months. Rotenoid biosynthesis decreased with frequent subcultures of callus tissue, and was finally lost. Callus with imperfectly differentiated rootlets induced from the leaves or stems by regulating plant hormones contained rotenoids which were identified as rotenone and deguelin. The rotenone content was 160 μg/g on dry weight basis. In other experiments in the Philippines root regeneration from calli induced from internodes, nodes and axillary buds of D. elliptica was obtained 3-5 weeks after inoculation on Shenck and Hildebrandt's medium supplemented with naphthalene acetic acid. Using Durham's test for rotenone, 60-100% of the calli and regenerated roots showed a positive reaction.

Husbandry

Derris can be raised as a sole crop, or as an intercrop e.g. with rubber, kapok, coconut and cocoa. It needs full sunlight, however, so shading by the main crop should be avoided. Fertilizer application should be during the rainy season. The crop requires high K and P but low N. Trellising considerably increases the number of usable cuttings and the yield of roots.

The crop remains in the field for two years if the trailing cropping method is used. As the crop does not cover the soil completely during the first year, great care should be taken to prevent soil erosion. Hillsides are not suitable and the soil should be covered. To facilitate harvesting, soils must not be too heavy.

Diseases and pests

Some fungal diseases are reported to damage planted D. elliptica: a rust (Ustilago derrides), a Gloeosporium sp. that causes the shoot tips to die, and an unidentified fungal disease that attacks cuttings in nursery beds. Pests are not serious and are easily controlled.

Harvesting

In cultivation, the roots are often harvested before the plants flower, usually 2 years after planting. They generally grow no deeper than about 50 cm and are dug out carefully, taking care to minimize damage to the bark. On large plantations, the harvested area is cleaned and then replanted. In small plantings with trellised plants all roots are removed, except for those directly under the plants, leaving the top part intact. This root-pruning practice enables several harvests from the same plant. Regeneration, however, is slow.

Yield

The yield of dried D. elliptica roots is 1100-1800 kg/ha, occasionally up to 3000 kg/ha, particularly when plants are trellised. The weight of a fresh D. malaccensis root is up to 900 g. Yields of rotenoids reported in literature vary widely, depending on species and cultivar, age of the plants and ecological conditions.

Handling after harvest

After harvesting, the roots are cleaned, preferably in running water, and rapidly dried in the sun or in an oven at approximately 50 °C to about 10% moisture content. Drying can be speeded up by cutting the roots into pieces up to 5 cm long. The roots can be stored in a cool and dry place. However, drying the roots seems to degrade the active constituent, particularly when stored too wet.

Rotenoid content is highest in roots 2-10 mm in diameter. So it is advisable to sort the roots into two groups before packing, those smaller and those larger than 1 cm in diameter. The roots are pressed into blocks of 100 kg or, if cut into chips, packed in bags of 50 kg. The packing material should be waterproof because a high moisture content will cause rapid deterioration. Dinoderus minutus and Sinoxylon anale beetles feed on the dried roots and can cause considerable damage. Protection is possible by fumigation. If the product is to be used in dusting or spraying, the dried roots are ground into a fine powder. The powder remains effective for a long time if it is protected against air, sunlight and moisture.

Proper ventilation, the use of masks and strict attention to hygiene are a prerequisite when manufacturing Derris insecticides to prevent complaints such as dermatitis and irritation of mucous membranes.

Fresh roots are usually fermented with water for 24 hours to obtain an aqueous solution of the toxic principle. For application against snails in wet rice Derris roots are chopped and crushed, and then scattered over the field for at least 24 hours. This procedure is suitable for rice fields without fish. Often a solution is prepared for spraying. For this, chopped and crushed roots are first soaked in water (90 kg of roots per ha in 200-300 l water) with 0.1% soap solution and subsequently sieved and squeezed. The solution is boiled for one hour and immediately sprayed. It should not be kept for more than 24 hours. If it rains or the water level increases, the treatment should be repeated after 3-5 days.

For use in ponds against predatory fish, roots are chopped into pieces of 2-3 cm and ground (e.g. with a laboratory pulverizer) and then sieved to obtain the root powder, which can be used to selectively poison fish without killing prawns.

To use Derris as a fish poison in the Solomon Islands, leaves are put into a hole together with an equal amount of sand and pounded. The resulting granular green mixture is then spread under water, and poisoned fish exhibiting extreme disorientation are speared or collected from the surface of the water.

Genetic resources and breeding

In South-East Asia, several Derris species are widely distributed as wild plants, but some species (particularly D. elliptica and, to a lesser extent, D. malaccensis) have been cultivated in gardens since antiquity. This has resulted in the present situation where, e.g. in Java, wild plants of D. elliptica vary widely but have a low rotenone content (about 0.5%), whereas the cultivated plants vary little but have a high rotenone content (12-13%). Collections of both provenances are available. Hybrids between D. elliptica and D. malaccensis have shown promising results. Breeding trials have been hampered by the almost total self-incompatibility or cross-incompatibility of most cultivars of D. elliptica.

Prospects

There is a renewed interest in the use of Derris as a pesticide because of the problems arising from repeated application of synthetic chemical insecticides, which are, however, often cheaper and more effective. Preparing a solution for use in the field is a simple procedure that can be done by the farmer. Moreover, the active compounds are completely detoxicated within one week and the effect on the environment is limited. Derris roots and their extracts are cheaper and more potent than pyrethrum, and are simple and convenient to apply. It has been reported that they have low toxicity for higher animals. However, determination of the toxicity of the insecticide to mammals and other non-target organisms needs further investigation. Because of the lack of convincing data, Derris insecticide has been banned in some countries (in the Netherlands, for instance) since about 1980.

Literature

Blasko, G., Shieh, H.-L., Pezzuto, J.M. & Cordell, G.A., 1989. 13C-NMR spectral assignment and evaluation of the cytotoxic potential of rotenone. Journal of Natural Products 52(6): 1363-1366.
Council of Scientific and Industrial Research, 1952. The wealth of India. Volume 3. New Delhi, India. pp. 35-41.
Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York and London. pp. 73-77.
Geesink, R., 1989. Derris elliptica (Sweet) Bentham. In: Westphal, E. & Jansen, P.C.M. (Editors): Plant Resources of South-East Asia, A selection. Pudoc Wageningen, the Netherlands. pp. 112-114.
Guerrero, R.D., Guerrero, C.A. & Garcia, L.L., 1990. Use of indigenous plants as sources of fish toxicants for pond management in the Philippines. Philippine Technology Journal 15(2): 15-17.
Kodama, T., Yamakawa, T. & Minoda, Y., 1980. Rotenoid biosynthesis by tissue culture of Derris elliptica. Agricultural and Biological Chemistry 44(10): 2387-2390.
Maini, P.N. & Morallo-Rejesus, B., 1993. Molluscicidal activity of Derris elliptica (Fam. Leguminosae). Philippine Journal of Science 122(1): 61-75.
Rickard, P.P. & Cox, P.A., 1986. Use of Derris as a fish poison in Guadalcanal, Solomon Islands. Economic Botany 40(4): 479-484.
Spoon, W. & Toxopeus, H.J., 1950. Derriswortel [Derris root]. In: van Hall, C.J.J. & van de Koppel, C. (Editors): De landbouw in de Indische Archipel [Agriculture in the Indonesian Archipelago]. Vol. 3. Van Hoeve, 's-Gravenhage, the Netherlands. pp. 578-608.
Verdcourt, B., 1979. A manual of New Guinea legumes. Botany Bulletin No 11. Office of Forests, Division of Botany, Lae, Papua New Guinea. pp. 314-331.

Selection of species

Authors

Auzay Hamid