Saline Agriculture: Salt-Tolerant Plants for Developing Countries (1990)

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4 Fiber and Other Products INTRODUCTION Salt-tolerant plants can be used to produce economically impor- tant materials such as essential oils, gums, oils, and resins, pulp and fiber, and bioactive compounds. Further, salt-tolerant plants can be cultivated for landscape use and irrigated with saline water, thereby conserving fresh water for other uses. ESSENTIAL OII S Kewda The male flowers of kewda (Pandanus fascicularis), a common species of screw pine in India, are used to produce perfume and fla- voring ingredients. The flowers are charged to a copper still, water added, and the mix distilled. The steam and essential oil (approxi- mately 0.3 percent by weight of the flowers) are condensed to produce kewda water, or the kewda vapors are captured in sandalwood oil and formulated from this base. The kewda plant is salt tolerant and has been planted in coastal areas to check drifting sand. Propagation is through suckers or stem cuttings, and flowering starts ~4 years after planting. An annual income of US$8 per plant has been estimated. 103

~4 TBe s~lt~tole:~t We (~c~) grows E~ 2~ to 3 ~ fish ~ coasts India. Began amen ~ asps to~SSusSe pe~e ~6 fig Ogres. toned Boa plow g_ on sager Mange sdiI. T Are evaluated ~ ~ bar peppermint oily Ad ~ {6 men~tbol) both gage CHIN chorale to thou Stied on nor ., : ^ ., ~ . ... , ~ . ^ : , , ~ as. ~ sag. i. ~. . , ~,. ~ . ,, . . , , ~^ ~ mcluc~ ~ If Aver: ~$~ ~- >~ ~ Ad ~ ~< (far c~r~ella oil); ~ ~f~> C:f~ #~rf/~, Ad /~et6~= ~a {E~1~E dilll. ~(~ oilplaat,is ~sorepo~edtogio~ unserved oder~telys~iF~econdit~nsS Tbeproductlon of en ol~top~ov~idean~{souroeofinc6~e in rural areas ~ one of the objectives of the Ciskei E~se~ti~ Offs Projects established id southern Judaica in 1972. , t ~.. a, ^ ., ~. . . . . Other oldectlves Include age ~O~l~C8110# 01 e~tr~actlo~ tec~m~ue for use ~ rural Resend t~heide~ti5cadon of~ike~ far the oils produced a. . ~ , . ~ 11ttiC Colts. resources and requlreJ O-r He pan ~ ~; ~ ^~ baa

105 produced and exported US$1 million worth of essential oils and pro- vided employment to hundreds of rural dwellers during the harvest season. Although the use of salt-tolerant plants is not the focus of the Ciskei Project, the principles could be applied to provide employment and income in areas where saline water or soil occurs. GUMS, OILS, AND RESINS Sesbania bispinosa, commonly known as dhaincha in India, is an important legume and fodder crop. It is an erect, multibranched annual, about 2.5 m tall at maturity that grows readily on alkaline saline soils. Often grown for use as a green manure (about 12 tons per hectare), its stalks are sources of fiber and fuels and the seeds yield a galactomannan gum that can be used for sizing and stabilizing purposes. The seed meal can be used for poultry and cattle feed. S. sesian and S. speciosa are salt-tolerant perennials used as green manure. S. sesban can tolerate waterlogging and salt concentrations of 1.0 percent as a seedling and 1.4 percent as it matures. GTindelia camporum is a 0.5-1.5 m resinous perennial shrub. It exudes large amounts of aromatic resins that cover the surface of the plant. The resins are nonvolatile mixtures of bicyclic terpene acids, esters, and related structures that are insoluble in water but soluble in organic solvents. The amount of resin produced ranges from 5 to 18 percent of the dried biomass. The plant appears to be salt tolerant; populations are found in saline flats and near salt lakes and springs. Several species of Grindelia occur along the North American Pacific Coast in estuaries or salt marsh habitats. These include G. humilis, G. stricta, G. latifolia, and G. integrifolia. All produce diterpene acid resins. Grindelia resins have properties similar to the terpenoids in wood and gum rosins, which are used commercially in adhesives, varnishes, paper sizings, printing inks, soaps, and numerous other industrial applications (Figure 3~. With increasing costs and declining supplies of these wood-based materials, substitutions with Grindelia resins in this market (700,000 tons per year) may become practical. The creosote bush (Larrea tridentata) grows over large areas of the Chihuahua, Sonora, and Mojave deserts of North America. Eval- uations of [arTea resins have shown potential uses as an antioxidant for rubber, as an antifungal agent for agricultural applications, and as a reactive material for polymerization with formaldehyde. Sapium sebiferum, the Chinese tallow tree, is a small marshland

106 i' COOH a W ~ COOH o c ~,1~ COOH b ~~ t~-COOH 11 d FIGURE 3 Diterpene Acids. Gr~ndelia resins have properties similar to wood rosins, which are used in a wide variety of industrial applications. Diterpene acids from Pin?= (a,b) and Gr~r~delia (c,d) are remarkably similar. SOURCE: B.N. Timmerman and J.J. Hoffmann, 1986. tree native to subtropical China. It has been cultivated there for more than 1,000 years as a source of specialty oils, medicines, and vegetable dyes. The Chinese tallow tree possesses several valuable characteristics: it can be seeded directly; it grows rapidly in warm, waterlogged saline soils; and it resprouts readily. The major economic potential for this tree is in its high yield of oiTseed more than 10 tons per hectare according to the USDA. The seed contains both an edible hard vegetable fat and an inedible liquid oil, which comprise 45-50 percent of its weight. These oils are physically separated in the seed and may be isolated separately. The edible fat is a potential substitute for cocoa butter and the inedible of! (stillingia oil) appears promising as a drying of! for paints and varnishes. Of the total lipid content in the seed, 30-50 percent is the edible fat. The seed meal, after extraction of the oil, has a high protein content. It can be used for feed or, with suitable treatment, for human

Rubber rabbitbush grows on saline soils in western North America. It con- tains natural rubber, a hydrocarbon resin, and constituents that are potential pesticides. (D.J. Weber) consumption. Five years after planting, when seed production begins, a net return of US$3,200 per hectare per year has been estimated. Jojoba* (Simmondsia chinensis) is a perennial desert shrub with seeds that contain a unique oil. About half of the seed's weight is an of! with a structure similar to sperm whale oil an ester of a C20_22 straight chain alcohol with a C20_22 straight chain acid. Both the alcohol and the acid have a terminal double bond, providing a readily accessible site for diverse chemical reactions. This oil and its derivatives have been used primarily in cosmetics, but broader use as a component in specialty lubricants and waxes will probably develop when increased oil production brings lower prices. Currently there are about 16,000 hectares of jojoba plantations in the southwestern United States and other plantations in Mexico, Australia, Israel, Argentina, and South Africa and other African nations. *See also Jojoba: New Crop for Arid Lariat, New Crop for Industry. To order, see p. 135.

108 Jojoba is relatively salt tolerant. In California, plants are grow- ing satisfactorily with water containing 0.2 percent salts. In labo- ratory testing, one variety of jojoba showed no reduction in flower production with 0.6 percent salt. In Israel, jojoba is growing well near the Dead Sea irrigated with brackish water (~6 dS/m). While natural rubber occurs in over 2,000 plant species, the com- mercial source is the rubber tree, Hevea brasiliensis. Natural rubber consists of cis-1,4-polyisoprene units. It is preferred in applications that require elasticity, resilience, tackiness, and low heat buildup. It is indispensable for bus, truck, and airplane tires. In 1980, the United States imported about 700,000 tons of natural rubber; im- ports of about 1 million tons are anticipated for 1990. Rubber rabbitbush (Chrysothamnus nauseosus) is a common desert shrub native to western North America. It grows under a wide range of environmental conditions from Mexico to Canada, commonly appearing on disturbed sites and saline soil. In addition to its forage value, it contains natural rubber and a hydrocarbon resin, and it has constituents that are potential insecticides and fungicides. The perennial desert shrub, guayule (Parthenium argentatum), has also been used as a source of natural rubber. $ In 1944, there were 12,000 hectares of guayuTe planted in California (USA) for rubber production. In tests with guayule, total rubber yields first increased and then decreased as soil salinity increased (Table 14~. Interest has recently been revived in guayuTe for natural rubber. More recent reports on guayule (Ho~man et al., 1988; Maas et al., 1988) indicate the root-zone salt-tolerance threshold to be about 7.5 dS/m; above this, rubber Production is reduced 6.1 percent ner unit increase of soil salinity. Rubber samples from Hevea, Parthenium, and Chrysothamnus appear to be structurally identical. Rubber contents as high as 6.5 percent for Chrysothamnus have been reported. If rubber yields of 2 percent are assumed, a plantation would produce 370 kg per hectare after 6 years' growth (guayuTe yields from California production were higher about 1,000 kg per hectare after 2 years; Hevea yields are about 1,300 kg per hectare per year). Resin contents as high as 21 percent have been reported for Chrysothamnus, and some of its hydrocarbon components may find use as insecticides and fungicides. ,¢ ~ *See also Guayule: An Alfcrr~atinc Soured of Natural Rubber. To order, see p. 135.

109 TABLE 14 Plant Growth and Rubber Content of One-Year-Old Guay~le Plants at Three Soil Salinities. Fresh Top Soil Salinity Plant Height Weight dS/m cm g Rubber % 3.2 53 397 3.32 8.7 52 388 6.05 13.2 44 286 4.61 SOURCE: Frangois, 1986. Compared with guayule, Chrysothamnus has several advantages as a potential source of natural rubber. Guayule generally requires good soil, good moisture conditions, and good horticultural practices. Guayule must be grown in frost-free areas because freezing kills it. In contrast, Chrysothamnus grows on poor soil, on disturbed sites, and on saline soil. It is found from the hot desert of Arizona to the western arid regions of Canada; there are subspecies that grow at sea level and others that grow at 3,000 m. The rubber content of these plants is similar to that of guayule in natural populations. PULP AND FIBER Phragmites australis, common reed, is an ancient marsh plant that has served in roofing, thatching, basketry, and fencing, as well as for fuel. It grows throughout the world in areas with saturated soils or standing water 2.5 m deep or less. The water can be fresh or moderately saline. Nearly any soil from peat to sand is tolerated. Little data exist for yields from managed stands. In the harvest of natural stands, however, productivity is consistently estimated to be about 10 dry tons per hectare. There is current use and broader interest in the manufacture of paper and other cellulose derivatives from this plant. In Romania, 125,000 tons of Phragmites are harvested in the Danube delta each year for use in papermaling. The pulp from these reeds is blended with wood pulp to give a stronger final product. In Sweden, extensive stands of Phragmites have been suggested as an alternative fuel for winter heating. This reed has about 40 percent (by weight) of the energy content of heating oil. In Egypt, two rushes, Juncus rigidus and ]. acutus, have been /

110 TABLE 15 Genninaiion of Junc~ spp. With Increasing Salinity. Germination % NaC1% at 25°C 0.1 1.0 2.0 3.0 J. rigidus 100 100 95 63 J. acutus 15 5 0 0 SOURCE: Zahran and E1 Demerdash, 1984. investigated with particular emphasis on their potential use in paper- making. In pilot-level testing, the strength properties of unbleached ]. rigidus pulp were found to be 73 percent of the kraft pulp ordi- narily used. In similar tests, rice straw and bagasse pulps gave only 24 and 42 percent of the strength of kraft pulp. In germination and propagation testing, ]. rigidness was much more salt-tolerant than ~1. acutus. Germination results are shown in Table 15. When rhizomes of these two species were planted on saline test plots, the vegetative yield of J. rigidus was almost twice that of ~1. acutus. In studies of the effects of nitrogen and phosphorus fertilizers, vegetative yields and fiber lengths in both species were improved. Increased fiber lengths are an indicator of improved performance in papermaking. -1. rigidus has also been introduced to India from Egypt. Germi- nation, seedling growth, and evaluation of nine-month culms in India indicate that 1.5-2.0 tons per hectare of pulp for papermaking can be produced on saline soil. The textile screw pine, Pandanus tectorius, abounds in tidal flats of Southeast Asia, Malaysia, and Polynesia. The leaves are traditionally and widely used for thatching and basketry. They are also used to fashion wallpaper and lampshades. Esparto grass (Stipa tenacissima) grows in semiarid areas of North Africa. It covers more than 7 million hectares in Algeria and 1.5 million hectares in Tunisia. It has been used for more than a cen- tury in papermaking. The paper produced from this fiber is smooth, opaque, and resilient. A paper mill in central Tunisia produces more than 70,000 tons of pulp and paper from this grass, and 20,000 rural fannies find seasonal work harvesting the crop. In addition, a veg- etable wax extracted from the grass before pulping can be used as a substitute for carnauba wax.

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112 At... ~ . .. ~ ~ ~ ~ ~ ~ .. t~ ~.~.~ ~ ,~ .. ~ ~.~. s. .8i.~ -. ~ ~I. .. ~. ~ ~..~ I. F~ ~. .. .. A. .. ........ A : The American oil palm, Elacis olcifcra, is found in coastal swamp forests from the lower basin of the Amazon to southern Mexico. Its fruits are a source of oil and tallow, similar to that obtained from the African oil palm. The tree has a low growing habit, which eases fruit harvest. (M.J. Balick) mangrove swamps, and tidal streams throughout the tropics. The bark fiber is used for ropes, fishing lines' and nets. Urochondra setulosa is a halophytic grass of the Indus delta and saline marsh flats of the Pakistan coast. This plant dominates sites with ECs of 34-62 dS/m. It merits evaluation as a fiber source. Cotton (Gossypium hirusutum) production using saline water has been examined in the United States, India, Israel, and Tunisia. In Israel, using drip irrigation and four levels of water quality (EC = 1.0, 3.2, 5.4, and 7.3 dS/m), salinity did not reduce yields even at the highest level. In the United States, cotton was drip irrigated with 8.5 dS/m saline water on saline soil in the presence of a saline water table. The yields were equal to that of a control plot that was irrigated with fresh water. In India, three cotton varieties were reduced in growth and yield when irrigated with seawater diluted to 10,000 and 15,000 ppm salts. In Tunisia, two varieties of cotton were grown with irrigation water containing 0.25, 1.43, 2.43, and 3.45 g per liter of soluble salts. Yield increases of 30-34 percent were obtained at the highest salt level.

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114 Many attractive halophytes can be used as landscape plants or for floral use, especially in areas with constraints on the use of fresh water. Sea lavender, for example, can be irrigated with seawater and used to produce cut flowers. (G. Shay) source of oil, and tapping of the inflorescence for toddy and sugar are all well known. In addition, leaves are used for thatching, walls, and screens, and leaflets are woven into baskets, plates, hats, mats, and other articles for daily use. Fibers from the husk are used for brushes, mats, twine, rope, stuffing for mattresses and upholstery, and for caulking boats. Elaeis oleifera is found in coastal swamp forests from the lower basin of the Amazon to southern Mexico. Often called the American

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116 CH3 1 C CO CH3-CH H3CO `,~,O CO >Jo H3C CH3W FIGURE 4 Callophyllolide. A promising agent for the treatment of indlam- matory and rheumatic conditions, callophyllolide, has been isolated from the seeds of Calophyllum ir~ophyllum, a plant of coastal southern India, Burma, and Sri Lanka. Source: R. C. Saxena et al., 1982 used for walls in native dwellings and its fibers are used for fishing nets and cordage. Raphia vinifera, the bamboo palm, grows in tidal bays and creeks in tropical West Africa. Fiber from the leaf bases is used for fishing lines and for animal snares and cordage. It is also exported for use in the manufacture of brooms, industrial brushes, and upholstery stuffing. BIOACTIVE DERIVATIVES CallophyIlolide (Figure 4), a complex 4-pheny! coumarin, has been isolated from the seeds of CalophyIlum inophyilum (Alexandrian laurel), a common evergreen tree of coastal southern India, Burma, and Sri I,anka. In preliminary testing against oxyphenbutazone, a widely prescribed antiinflammatory, callophyIlolide appears promis- ing for the treatment of inflammatory and rheumatic conditions. The seed of! can also be saponified to give a soap with antibacterial prom erties. Extracts of the bark and leaves of C. inophyIlum are used in traditional Indian medicine. These extracts have been qualitatively analyzed to show the presence of steroids and alkaloids.

117 ~the~r p.o$e~1~1 on! ~B~~ )~ ~1~s gun city seaters Ir~l~tio~. (C.. Sag) contain 3~4 Percent dios~ge~ln. Of ste:~dal dru . Ha. . a- . i ~los~mn . }= Eke rice facts pan ^ great Hers ~ Iity Progesterone and oraDy active progesterone . . ~ at.. rogues can he regally s~yntbesis and cortisone and otter usefulcorticosteroi] ~ ~ ~ a. . produced grow glossed n through cbem~lc~ by

118 microbial synthesis. For the manufacture of most current contracep- tive drugs, however, the preferred starting material is sitostero! from soybean of! extraction wastes. A recent discussion paper published by FAG suggests that dios- genin could be produced in the Sudan from the fruits of Balanites aegyptiaca. The paper calculates that the Sudan could produce 1,200 tons per year, enough to meet about half the world demand and earn an export income of $36 million. The neem tree (Azad:irachta indica) has great potential for agri- cultural and commercial exploitation. It is a fast-gro~nug tree that can be established on poor soils unsuitable for farming. Fruiting begins at about five years. Although neem seed of! is inedible, it is traditionally used in soapmaking. More importantly, neem seed ex- tracts are effective in the control of several insect pests. The extracts act both as antifeedants and pesticides, and appear to be nontoxic to humans and animals. Neem seedlings have been grown success- fully in Pakistan on sandy soil using irrigation water with an EC of 17 dS/m. A neem plantation has been established near Mecca in Saudi Arabia to provide shade for Muslim pilgrims. Water with an EC of 4.25 dS/m is used for irrigation. Various extracts of Adhatoda vasica, a salt-tolerant evergreen shrub common in India, are effective as antifeedants, insecticides, viricides, and as wound healing agents for water buffalo. The alkaloid vasicine is found in the leaves and bark at 0.2-0.4 percent. Extracts are also used in commercial preparations for the treatment of asthma and bronchitis. A. vasica has also been grown as a firewood crop. (See p. 63~. The perennial herb Anemopsis californica is found in semisaline and alkaline wetland soils in the southwestern United States and northwestern Mexico. It has long been esteemed for medicinal pur- poses in this region and continues to be widely used in Sonora. Extracts from the large roots (up to a meter in length) are used in- ternaDy for colds, coughs, or indigestion, and externally for wounds or swellings. One of the active ingredients appears to be 4-aDylveratrole, a maid antispasmodic. Periwinkle (Catharanthus roseus), a tropical plant found in the coastal sands of India, has been found to grow under saline conditions (up to 12 dS/m). Catharanthus roots contain alkaloids used in the treatment of leukemia, and its leaves contain alkaloids reported to lower blood pressure.

119 TABLE 16 Bioaciive Matenals Isolated Fran Salsola Species. Species Compound Amount Potential Use 5. richteri Salsolinol S. kali Salsolidine 0.2% S. richteri and S. ruthenica Salsoline S. subaphylla N-feruloyl- putrecine 0.2% S. pestifer Carotene 4.5 mg/lOOg Vitamin S. pestifer Ascorbic acid 77 mg/lOOg Vitamin Heart stimulant, binds to brain neuroreceptors Antihypertensives, vasodilators Weakly antihyper- tensive S. gemmascens Citnc acid 3.4% Food additive SOURCE: Adapted from Fowler, 1985. Derris trifoliata, a climbing vine, abounds in mangrove forests and along muddy shores from East Africa to India and through Malaysia to Polynesia. The leaves, which contain rotenone, are pounded and put in shallow water to stun fish. Such toxicants can be used to elirn~nate predators and competitors in freshwater and brackish water ponds to be used for the culture of crustaceans and finfish. Other mangrove vegetation has similar uses. The bark and seeds of Aegiceras corniculatum, Av~cennia alla, Barringtonia amatica, and the roots of Heritiera littoralis all contain a fish poison, and the milky sap of Excoecaria agallocha is used as a fish and arrowhead poison. C*rullus colocynthis, a creeping plant, occurs in the warmer parts of Asia and Africa. It is common on the seashores of west- ern India and is used to control drifting sand in coastal Pakistan. The dried pulp of its unripe, full-grown fruit constitutes the drug colocynth, which is used as a cathartic. In addition to the potential for Russian-thistIe (Salsola iberica) as a fodder source (p. 76), other Salsola species contain recoverable amounts of bioactive materials. Some of these are shown in Table 16.

120 TABLE 17 Salt-Tolerant Ornamental Plants. Mower Flowenng Average Salt Plant Color Season Height(m) Resistance Trees: Acacia gerrardii cream July-Oct 5 1 A. horrida yellow May-Sept 8 1 A. rad~diana cream Mar-Apr 5 1 Oct-Dec A. salicina cream Mar and Sept 8 1 A. tortilis cream Spring and Fall 5 1 Casu~rina glauca Apr 8 1 Conocarpus erectus s Elaeagnus angustifolia white Apr-May 4 Eucalyptus sargentii yellowish- 6 white Moringa peregrina white Mar-May 6 to pink Parkinsonua aculeata yellow May-June 8 2 Phoenix dactylifera 12 2 Prosopis juliflora white Apr-May 6 1 Tamers aphylla white May-June 8 2 Shrubs: Atriplex barclayana 1.5 2 A. cinerea 1 2 A. nummularia 1.5-2 2 Callistemon rigidus red Apr 2 1 Cassuz mexicana yellow Apr-Sept 0.5-0.75 1 Colutea istria yellow Mar-Apr 2 1 Maireana sedifolia 2 2 Melaleuca nesophila lilac May-July 3 1 Retama raetam white/ Mar-Apr 2 1 purple Tamarix chinensis violet 3 1 "mapu" LANDSCAPE AND ORNAMENTAL USE Many attractive halophytes can be used as landscape plants, especially in areas with constraints on the use of fresh water for watering or irrigation. In Israel, trees such as Conocarpus erec- tus, Eucalyptus sargentii, and Melaleuca halmaturorum, and shrubs such as Maireana sedifolia, Borrichea frutescens, and Clerodendrum inerme are sold for amenity planting to allow irrigation with saline

121 TABLE 17 (Continued) Flower Flowenng Average Salt Plant Color Season Height(m) Resistance Succulents and Semi-Succulents: Agave Americana white Apr-July 2 1 Arthrocnemum fruticosum* 0.6 3 A. macrostachyam 0.5 3 Batis maritime 0.3 3 Biennial and Perennial Ground Cover: Arctotis grandis assorted Dec-Apr Aster alpinus blue Dec-Apr Catharansus roseus white/ Most of year pink Cineraru: merits violet Apr-June 1 Crithrnum maritimum yellow May-June 2 Gazania splendens assorted Dec-May 1 Inula crithmoides yellow June-July 3 Nitraria billardieri white Apr-May 3 Ses~vium verrucosum lilac June-July 3 Lawn Grasses: Cynodon dactylon Paspalum vaginatum 2 2 Salt resistance: arbitrary degrees according to soil electrical conductivity: 1 = 5-15 dS/m; 2 = 15-25 dS/m; 3 = 25-50 dS/m. *Thnves under conditions of waterlogging. SOURCE: Adapted from Pastemak et al., 1986. water. A selection of salt-tolerant ornamental plants is shown in Table 17. The striking floral display of the Butea monosperma tree (p. 63) has earned it the name "flame of the forest." In addition, plants such as Limonium species have potential for floral use. For example, sea lavender (Limonium axiliare) can be irrigated with seawater and used to produce cut flowers.

122 REFERENCES AND SELECTED READINGS General Balandrin, M. F., J. A. Klocke, E. S. Wurtele and W. H. Bollinger. 1985. Natural plant chemicals: sources of industrial and medicinal materials. Scicnec 228:1154-1160. Hinman, C. W. 1984. New crops for arid lands. Scicnec 225:1445-1448. Vietmeyer, N. D. 1986. Lesser-known plants of potential use in agriculture and forestry. Scicr~cc 232:1379-1384. Essential Oils Kemp Dutta, P. K., H. O. Saxena and M. Brahman. 1987. Kewda perfume industry in India. Economic Botany 41:403-410. Mentha and Other Species Chandra, V., A. Singh and L. D. Kapoor. 1968. Experimental cultivation of some essential oil bearing plants in saline soils. Perfume and Essential Oil Review. December:869-873. Graven, E. H., B. Gardner and C. Tutt. 1987. Essential oils- new crops for Southern Africa. Cisici Agricultural Journal 1:2-8. Patra, P. and P. K. Dutta. 1979. Studies on salinity tolerance in aromatic and medicinal plants. Journal of the Orissa Botanical Socicly 1~1~:17-18. Piprek, S. R. K., E. H. Graven and P. VVhitfield. 1982. Some potentially important indigenous aromatic plants for the eastern seaboard areas of Southern Africa. World Crops 10~4~:255-263. Gums, Oile and Resins General Forti, M. 1986. Salt tolerant and halophytic plants in Israel. Reclamation and Revegetatior. Rcscarch 5:83-96. Greek, B. F. 1987. Modest growth ahead for rubber. Chemical and Engineering NEWS 66~12~:25-51. Sesbania Chahda, Y. R. (ed.~. 1972. Sc~bania. The Wealth of India. 1X:293-303. CSIR, New Delhi, India. Chandra, V. and M. I. H. Farooqi. 1979. Dhaincha for reed gum. Extension Bulletin No. 1. National Botanical Research Institute, Lucknow, India.

123 Gorham, J., E. McDonnell and R. G. Wyn Jones. 1984. Pinitol and other solutes in salt-stressed Scebar~ia aculc~a. Zcitschripc fur Pfanzenghy~ologic 4:173-178. Grindelia Hoffmann, J. J. and S. P. McLaughlin. 1986. Grindelia camporum: potential cash crop for the arid southwest. Economic Botany 40:162-169. Schuck, S. M. and S. P. McLaughlin. 1988. Flowering phonology and outcrossing in tetraploid Grindelia camporum Greene. Dcscrt Plants 9~1~:7-16. Timmerman, B. N. and J. J. Hoffmann. 1985. The potential for the com- mercial utilization of resins from Grindelia campor~ Pp. 1321-1339. in: E. E. Whitehead, C. F. Hutchinson, B. N. Timmermann, and R. G. Varady (eds.) Arid Lands Today and Tomorrow. Wesiview Press, Boulder, Colorado, US. Larrea tridentata Belmares, H. and A. Barrera. 1979. Polymerization studies of creosote bush (Lar- rca tridentata) phenolic resin with formaldehyde. Journal of AppEcd Polymer Scicnec 24 1531-1537. Belmares, H., A. Barrera, M. Ortega and M. Monjaras. 1980. Adhesi~res from creosote bush (Larrca tridentata) phenolic resin with formaldehyde. Charac- teristics and application. Journal of Applied Polymer Scicnec 25:2115-2118. Sapium sebiferum Chadha, Y. R. (ed.~. 1972. Sapium. Wcalth of In~a. 1X:229-231. CSIR, New Delhi, India. Scheld, H. W. and J. R. Cowles. 1981. Woody biomass potential of the Chinese tallow tree. Economic Botany 35:391-397. Scheld, H. W., J. R. Cowles, C. R. Engler, R. Kleiman and E. B. Shultz, Jr. 1984. Seeds of the Chinese tallow tree as a source of chemicals and fuels. Pp. 81-lol in: E. B. Shultz, Jr. and R. P. Morgan (eds.) FUCIJ and ChemicalJ from Oil~ced`. Westview Press, Boulder, Colorado, US. Jojoba Baldwin, A. R. (ed.) 1988. Procecding~: 7th Intcrnational Confcrcnec on Jojoba and ite Usc`. American Oil Chemists Society, Chicago, Illinois, US. Bhatia, V. K., A. Chaudhry, A. Masoh an, R. P. S. Bisht and G. A. Sivasankaran. 1988. Sulphurization of jojoba oil for application as extreme pressure additive. Journal of thc American Oi! Chemi~t~ Socicty 65~9~:1502-1507. Guayule Frangois, L. E. 1986. Salinity effects on four arid zone plant~ (Parthenium aryen- tatum, Simmond~ia chinen~i~, Kochia pro~trata and Kochia brcuifolia). Journal of Arid Enuironmcn~ 11:103-109. Hoffman, G. J., M. C. Shannon, E. V. Maas, L. Grass. 1988. Rubber produc- tion of salt-stressed guayule at various plant populations. Irrigation Scicr~cc 9:213-226.

124 Mans, E. V., T. J. Donovan and L. E. Frangois. 1988. Salt tolerance of irrigated guayule. Irrigation Scicr~cc 9:199-212. Miyamoto, S. and D. A. Bucks. 1985. Water quantity and quality requirements of guayule: current assessment. Agricultural Water Management 10:205-219. Chrysothamnus Ostler, W. K., C. M. McKell and S. White. 1986. C7`rusothanw nawcos~ a potential source of natural rubber. Pp. 389-394 in Proceedings - Symposium on the Biology of Artemisia arid Chry~othamr~w. USDA, Ogden, Utah, US. Weber, D. J., D. F. Hegerhorst, T. D. Davis and E. D. McArthur. 1987. Potential uses of rubber rabbitbrush (Chry~othamr~w r~awco~. Pp. 27-33 in: K. L. Johnson ted.) The Circus Chrysothamr~u`. Utah State University, Logan, Utah, US. Pulp and Fiber Reed de la Cruz, A. A. 1978. The production of pulp from marsh grass. Econorruc Botany 32:46-50. de la Cruz, A. A. and G. R. Lightsey. 1981. Pulping Charactcrutic~ and Paper Making Potential of Non-wood Wetland Plants. Sea Grant Publication MASGP- 80-016. Ocean Springs, Mississippi 39564, US. Graneli, W. 1984. Reed Phragrrutc~ awiralis as an energy source in Sweden. Biomass 4:183-208. Iyengar, E. R. R. and J. B. Pandya. 1983. Ju?3cus rigidly for saline soils. Indian Jourrza] of Agricultural Chemistry 16~13:147-152. Zahran, M. A. and M. A. El Demerdash. 1984. Transplantation of Junew rigidus in the saline and non-productive lands of Egypt. Pp. 75-131 Research in Arid Cones. Report No. 17, International Foundation for Science, Stockholm, Sweden. Zahran, M. A. 1986. Establishment of fiber producing halophytes in salt affected areas of Egypt. Pp. 235-251 in: R. Ahmad and A. San Pietro teds.) Prospects for Biosa~inc Research University of Karachi, Karachi, Pakistan. Typha Morton, J. F. 1975. Cattails (alpha spp.) - a weed problem or potential crop? Econorruc Botany 29:7-29. Saccharum grif~thii Ahmad, R. 1987. Saline Agriculture at Coastal Sandy Bcit. University of Karachi, Karachi, Pakistan. Hibiscus Frangois, L. E., T. J. Donovan and E. V. Mans. 1988. Salt tolerance of kenaf. Presented at 1st National Symposium for New Crops: Research, Development, Economics. October 23-26, 1988. Indianapolis, Indiana, US.

125 Kugler, D. E. 1988. Kcnaf Newsprint Rcal~ng Commercialization After Four Dccadc~ of Research and Dcvelopmcnt. USDA, Washington, DC, US. Sastri, B. N. (ed.~. 1959. Hibisew. The Wealth of India. V:75-98. CSIR, New Delhi, India. Cotton Ayars, J. E., R. B. Hutmacher, R. A. Schoneman, S. S. Vail and D. Felleke. 1986. Drip irrigation of cotton with saline drainage water. IPan~actsor" of the ASAE 29(6):1668-1673. Babu, V. R., S. N. Prasad, A. M. Babu and D. S. K. Rao. 1987. Evaluation of cotton genotypes for tolerance to saline water irrigations. Indian Journal of Agronomy 32~3~:229-231. Bouzaidi, A. and S. El Amami. 1980. Irrigation a l'eau sales de deux varietes de cotonnier dens lee essais de plein champ. Physiologic Vcgetalc 18~1~:35-44. Dean, P. 1981. Two-bale cotton with high-salt water. Agricultural Research (October) :10-1 1. Iyengar, E. R. R., J. B. Pandya and J. S. Patolia. 1978. Evaluation of cotton varieties to salinity stress. Indian Journal of Plant Physiology 21~2~:113-117. Mantell, A., H. Frenkel and A. Meiri. 1985. Drip irrigation of cotton with saline-sodic water. Irrigation Scicnec 6:95-106. Nawaz, A., N. Ahmad and R. H. Qureshi. 1986. Salt tolerance of cotton. Pp. 285-291 in: R. Ahmad and A. San Pietro (eds.) Prospects for Bio~alinc Rcacarch. University of Karachi, Karachi, Pakistan. Palms Balick, M. J. 1979. Amazonian oil palms of promise: A survey. Econorruc Botany 33:11-28. Morton, J. F. 1976. Craft industries from coastal wetland vegetation. Pp. 254 266 in: M. Wiley (ed.) Estuarinc Proccaece. Vol. 1. Academic Press, New York, New York, US. Pinheiro, C. U. B. and M. J. Balick. 1987. Brakeman Palms: Notes on their Usce and Vernacular Names. New York Botanical Garden, Bronx, New York, US. Plotkin, M. J. and M. J. Balick. 1984. Medicinal uses of South American palms. Journal of Ethnopharmacology 10~2~:157-179. Bioactive Deri~ratnes CalophyIlum inophyilum Mehrotra, S., R. Mitra and H. P. Sharma. 1986. Pharmacognostic stud ies on punnaga, Calophyllum inophyllum L., leaf and stem bark. Ncrba Hungaria 25~1~:45-71. Saxena, R. C., R. Nath, G. Palit, S. K. Nigam and K. P. Bhargava. 1982. Effect of calophyllolide, a nonsteroidal anti-inflammatory agent, on capil- lary permeability. Plan;ta Medico. Journal of Medicinal Plant Research 44~4~:246-248. Guevara, B. Q. and R. C. Solevilla. 1983. An antibacterial soap from bitaog oi Acta Manilana A, Natural and Applied Scicnece 22~11~:62-64. '1.

126 Balanites roxburghii Ghanim, A., I. Chandrasekharan, V. A. Amalraj and H. A. Khan. 1984. Studies on diosgenin content in fruits of Balanitce ro~b?`rghii. ILaneactions of the Ir~dsar~ Society of Desert Technology and Univcraity Center of Dcscrt Studies 9~2~:21-22. National Research Council. 1987. Workshop on Biotechnology of Steroid Compounds as Contraccptinc~ and Drugs. Summary Report. National Research Council, Jakarta, Indonesia, and National Academy Press, Washington, DC, US. Azaclirachta indica Ahmed, S., S. Bamoileh and M. Munshi. 1989. Cultivation of neem (Axadirachta indica, Meliaceae) in Saudi Arabia. Economic Botany 43:35-38. Ahmed, S. and M. Grainge. 1986. Potential of the neem tree (Azadirachta Ithaca) for pest control and rural development. Economic Botar~ 40:201-209. De~hmokh, P. B. and D. M. Renapurkar. 1987. Insect growth regulatory activity of some indigenous plant extracts. Insect Scicnec and Its Appli- cabon 8(1~:81-83. Kasmi, S. M. A. 1980. Mclia azadirachta A most common cultivated tree in Somalia. Somalia Range Bulletin 9:20-23. Radwanski, S. A. and G. E. Wickens. 1981. Vegetative fallows and potential value of the neem tree (Azadirachta indica) in the tropics. Economic Botany 35:398-414. Saxena, R. C. 1989. Insecticides from neem. Pp. 110-135 in: J. T. Arnason, B. J. R. Philogene and P. Morand teds.) Ineccheidcs of Plant Origin American Chemical Society, Washington, DC, US. Adhatoda vamca Arambewela, L. S. R., C. K. Ratnayake, J. S. Jayasekera and K. T. D. De Silva. 1988. Vasicine contents and their seasonal variation in Adhatoda vagina. Filotcrapia 59~2~:151-153. Bhargava, M. K., H. Singh, A. Kumar and K. C. Varshney. 1986. Adhatoda Mica as wound healing agent in buffaloes - histological and histochemical studies. Indian Journal of Yctcrinary Surgery 7~2~:29-35. Saxena, B. P., K. Tikku, C. K. Atal and O. Koul. 1986. Insect antifertility and antifeedant allelochemics in Adhatoda basics. Inkjet Scicnec and Its Application 7~4~:489-493. Tripathi, R. N., R. K. R. Tripathi and D. K. Pandey. 1981. Assay of antiviral activity in the crude leaf sap of some plants. Enuironmerd India 4~1/2):86-87. Anemopsis californica Childs, R. F. and J. R. Cole. 1965. Phytochemical and pharmacological investiga- tion of Anemop~ califorruca. Journal of Pharmacc~hcal Scic~cce 54~5~:789-791. Ezcurra, E., R. S. Felger, A. D. Russell and M. Equihua. 1988. Freshwater islands in a desert sand sea: the hydrology, flora, and phytogeography of the Gran Desierto oases of northwestern Mexico. Dcacr! Plank 9~2~:35-44,55-63.

127 Mangrove Toxicants De la Cruz, A. A., E. D. Gomez, D. H. Miles, G. J. B. Cajipe and V. B. Chavez. 1984. Toxic ants from Mangrove plants: I. Bioassay of crude extracts. Ir~tcrr~ational Journal of Ecological arid Er`'nronmcntal Scicnec 10:1-9. Gomez, E. D., A. A. de la Cruz, V. B. Chavez, D. H. Miles and G. J. B. Cajibe. 1986. Toxicants from mangrove plants: II. Toxicity of aqueous extracts to fish. The Philippine Journal of Scicr~cc 115~2~:81-89. Miles, D. H., D.-S. Lho, A. A. de la Cruz, E. D. Gomez, J. A. Weeks and J. L. Atwood. 1987. Toxicants from mangrove plants III. Heritol, a novel ichthyotoxin from the mangrove plant Hcritiera littoralis. Journal of Organic Chemistry 52:2930-2932. Citrullus colocynthis Bringi, N. V. 1987. Lesser known tree-borne oil seeds. Pp. 216-248 in: N. V. Bringi (ed.) Non-lFaditior~al Oila and Oil~ceds of India. Oxford and IBH Publishing Co., New Delhi, India. Sastri, B. N. teds. 1950. Citr?~llw colocyr~hi~. Wealth of India. II:185-186. CSIR, New Delhi, India. Russian-Thistle Fowler, J. L., J. H. Hageman, and M. Susukida. 1985. Evaluation of the Salinity Toleranec of Rwsiar~ Thistle to Determine its Potential for To rag c Production Ueir~g Saline Irrigation Water. New Mexico Water Resources Institute, Las Cruces, New Mexico, US. Landscape and Ornamental Use Pasternak, D., J. A. Aronson, J. Ben-Dov, M. Forti, S. Mendlinger, A. Nerd and D. Sitton. 1986. Development of new arid zone crops for the Negev Desert of Israel. Journal of Arid Enuiro?~mer~ts 11:37-59. Verkade, S. D. and G. E. Fitzpatrick. 1988. Development of the threatened halo phyte Mallontorua gnaphalodcs as a new ornamental crop. Presented at let National Symposium for New Crops: Research, Development, Economics. October 23-26, 1988. Indianapolis, Indiana, US. RESEARCH CONTACTS Essential Oils V. Chandra, National Botanic Gardens, Lucknow 226001, India P. K. Dutta, Aromatic and Medicinal Plants Division, Regional Research Laboratory, Bhubaneswar 751 013, Orissa, India. Earl Graven, Head, Department of Agronomy, University of Fort Hare, Alice 5700, Ciskei, South Africa.

128 Gums, Oile and Resin General V. Chandra, National Botanic Gardens, Lucknow 226001, India. M. Forti, The Institutes for Applied Research, Ben Gurion University, PO Box 1025, 84110 Beer-Sheva, Israel. E. Rodriguez, Phytochemical Laboratory, School of Biological Sciences, Univer- sity of California, Irvine CA 92717, US. Dhaincha R. G. Wyn Jones, Center for Arid Zone Studies, University College of North Wales, Bangor, Wales, LL57 2UW, UK. V. Chandra, National Botanical Research Institute, Lucknow 226001, India. Grindelia Stephen P. McLaughlin, Bioresources Research Facility, University of Arizona, 250 E. Valencia Road, Tucson, AZ 85706, US. Creosote Bush Hector Belmares, Centro de Investigascion en Quimica Aplicada, Aldama Ote. 371, Saltillo, Coahuila, Mexico. Chinese Tallow Tree Robert Kleiman, USDA Northern Regional Research Center, 1815 North Uni- versity, Peoria, IL 61604, US. H. W. Scheld, PhytoR~source Research, Inc., 707 Texas Avenue - Suite 202D, College Station, TX 77840, US. E. B. Shultz, Jr., Box 1106, Washington University, St. Louis, MO 63130, US. Jojoba Hal C. Purcell, Jojoba Grower's Association, 3420 East Shea - Suite 125, Phoenix, AZ 85028, US. David Palskill, Department of Plant Sciences, University of Arizona, Tucson, AZ 85721, US. John Rothfus, USDA Northern Regional Research Center, 1815 North Univer- sity, Peoria, IL 61604, US. Chrysothamnus nauseosus D. J. Weber, Department of Botany and Range Science, Brigham Young University, Provo, UT 84602, US.

129 Guayule Joseph Beckman, Firestone Tire and Rubber Company, 1200 Firestone Parkway, Akron, OH 44317, US. D. A. Bucks, US Water Conservation Laboratory, 4331 East Broadway, Phoenix, AZ 85040, US. S. Miyamoto, Texas Agricultural Experiment Station, 1380 A&M Circle, El Paso, TX 79927, US. Pulp and Fiber Cotton James E. Ayars, USDA-ARS, WMRL, Fresno, CA 93700, US. A. Mantell, Institute of Soils and Water, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. Akhtar Nawaz, Department of Soil Science, University of Agriculture, Faisalabad, Pakistan. James D. Rhoades, USDA Salinity Research Laboratory, 4500 Glenwood Drive, Riverside, CA 92501, US. Reed Armando A. de la Cruz, Department of Zoology, Mississippi State University, MI 39762, US. Wilhelm Graneli, Institute of Limnology, Box 3060, S-22003 Lund, Sweden. E. R. R. Iyengar, Central Salt and Marine Chemicals Research Institute, Bhavnagar 364 002, India. M. A. Zahran, Botany Department, Mansoura University, Mansoura, Egypt. Esparto Grass Director, Institut National de Recherches Forestieres, Ministere de ['Agriculture, Route de la Soukra, B.P. 2, Ariana, Tunisia. Typha J. F. Morton, Morton Collectanea, University of Miami, Coral Gables, FL 33124, US. Kenaf/Hibiscus Charles Adamson, USDA Plant Introduction Center, Route 1, Sharpsburg, GA 30277, US. Marvin O. Bagby, USDA Northern Regional Research Center, 1815 North University, Peoria, IL 61604, US. L. E. Frangois, US Salinity Laboratory, 4500 Glenwood Drive, Riverside, CA 92501, US.

130 Ply M. J. Balick, New York Botanical Garden, Bronx, NY 10458, US. J. F. Morton, Morton Collectanea, University of Miami, Coral Gables, FL 33124, US. Bioactive Derivatives Calophyilum inophyIlum S. Mehrotra, Pharmacognosy Section, National Botanical Research Institute Lucknow 22600, India. R. C. Saxena, Department of Pharmacology, King George's Medical College, Lucknow 226003, India. Balanites roxburghfi A. Ghanim, Central Arid Zone Research Institute, Jodhpur 342 003, India. Azadirachta indica S. A. Radwanski, Land Resources Consultancy, 361 Wimbledon Park Road London SW19 6PE, UK. G. E. Wickens, Royal Botanic Gardens, Kew, Surrey, TW9 3AB, UK. Commiphora unghtii S. Kumar and V. Shankar, Central Arid Zone Research Institute, Jodhpur 342003, India. Catharanus roseus P. K. Dutta, Aromatic and Medicinal Plants Division, Regional Research Laboratory, Bhubaneswar 751 013, Orissa, India. [andscape and Ornamental Use Dov Pasternak, Institute for Desert Research, Ben Gurion University, Sede Boger 84990, Israel. Stephen D. Verkade, University of Florida, 3205 College Avenue, Fort Laud- erdale, FL 33314, US.