f Okra l 350
~ l 69 Etoh, T. (1986) Fertility of garlic clones collected in Soviet Central Asia. J, Jpn. Soc. liorr. Sci. 55, 312-19. Okra Dommisse. E. hl., Leung, D. W. hl., Shaw, hl. L. and Abelmoschus esculentirs, A. caillei, Conner, A. J. (1990) Onion is a monocotyledonous host A. manihot, A. rnosclintus (Malvaceae) for Agrohocreriirm. Platir Science 69, 249-57. FenBick, C. R. and Hanley, A. B. (1985) Thc genus Alliitrn. Crir. Rev. Food Sci. Nutrir. 22, . (IYYO) 199-27 I FAO Quarterly Bitllerin of Srriri.srics. Food and 3. S. Hamon Agriculture Organization. United Nations, Rome. vol. Institut Française de Recherche Scientifique Hanelt, P. (1990) Taxonomy. evolution. and hi". In J. pour DCvcloppmcnt en Coopération. BP 3045 H. Rabinowitch and Brewstcr (cds). Omi~iswid allied crops. Montpellier. France Boca Raton, FL, pp. 1-26. Inden. H. and Asahira, 1'. Japanusc bunching and (1990) H.Thc onion (Allicini jisivlukosron). in D. Rahinowitch and J. D. H. van Sloten L. Brewstcr (cds). Otii~ti.~mid (illied crops. Boca Raton. FL. pp. International Board for Plant Genetic Resources. A. 159-7X. Jones, H. and Mann. I,. K. (1963) Ortioris and their Via delle Sette Chiese 142. (KI0145 Rome. Italy. ciNies. New York. McCollum,G.D.(1976)0nions;lndallies.InN. W.Sininionds, (ed.). E~~lurionuf crop plunts. London. pp. 186-90. Muren, R. C. (1989) Haploid plant induction from unpollinated ovarics in anion. florf. Scicnce 24. 8.134. Novai. F. J.. Havel, L. and Dolezel. J. (1986) Alhini Introduction In D. W. Evans, W. Sharp and P. Ammirato (eds). Handbook of plrnr cell cttltiire, rechniqiies and appli- Okra is a very popular. tasty, gelatinous vegetable. cutiotis, 4. New pp. 4lY-56. W.vol. York. Tender green pods 3-5 days old are used as a Stearn, (1944) Notes on thc genus A/hm in the Old vegetable, generally marketed in the fresh state but World. Herberriii II, 1 1-37. Traub, H. (1968) The order Alliales. f'lmir Life 24, sometimes in canned form (USA, Turkey). In dry 129-38. areas, fruits are cut into slices, dried in the sun and Van der Meer, Q. P. and Permadi, A. H. (1990) Research stored for long periods (Sahcl in Africa, India). They for the improvement of shallot production in Indonesia. are relished because of their high mucilage content. Onion hies-slerrerfor rhe Tropics 2. 18-21. Four species are cultivated. The main crop (Abel- Vvedensky, A. (1943) The genus in the USSR. Miurn moschus esculenrus) is an annual vegetable. grown Herberria 65-2 18. 11, from seed, in tropical. subtropical and mediterranean Wendelbo, P. (1969) Ncw subgencra. sections and species climatic zones. In West and Central Africa it is of Allium. Bor. h'orser 122, 25-37. cultivated, in association with A. cnillei where the former, which flowers earlier, is known as 'the rainy season okra'. and the latter, which has a longer cycle (up to 1 year). is known as the 'dry season okra'. Plants of A. nianiliol, whose pods are too prickly to be consumed and have sometimes lost their flowering ability, are only cultivated in Papua New Guinea for their leaves. Abehoschus moschatiis has seeds which are used as musk mallow (ambrette). This species is sometimes used in several animism practices in West Africa (south Togo and Benin). Okra has a relatively good nutritional value and is a good complement in developing countries where there is often a great alimentary imbalance. Moisture (89.6 percent). K (103 mg), Ca (90 mg), Mg (43 mg), (56 P mg), vitamin C (18 mg) are found in 100 g of fresh fruit. Metals such as iron and aluminium
1
Fonds Documentaire ORSTOM Okra 351
are found between 500 and 4000 ppm, the nitrogen This classification remains, however, incomplete in percentage is 16 per cent dry weight; the amino acids at least three points: Asp and Arg are each present at nearly 10 per cent (Markose and Peter, 1990). 1. Abelmoschus moschatur and A. manihot, con- c sidered as 'wide species' need to be studied in more detail to rationalize infraspecific categories; 2. Abelmoschus caiffei Chev. Stevels (1988), dis- Cytogenetic background covered by Chevalier (1940), is not taken into Okra, originally included in the genus Hibiscus, account and is often considered in some papers as section Abelmoschus, is now accepted as a distinct a form of A. manihot; genus on the basis of the caducous nature of the Abefmoschus tiibercufatus, must be considered as 3. A. calyx. A synthetic view, integrating the relationships a species, not as a wild form of escufenfus. between the different classifications that have been adopted, is given in Table 69.1. The taxonomic A summary of the taxonomic key is reported in work of van Borssum-Waalkes (1966) is the most Table 69.2. complete study. From fourteen species previously Very little work has been carried out on the described (Hochreutiner, 1924) six were retained. chromosome complement. The most detailed studies
Table 69.1 The systematics of the genus Abelmoschus.
~ ~~ Hochreutiner Van Borssum-Waalkes Today (1924) (1966) recommended A. A. crinitus crinitus - A. crinitiu A. ficulneus A. ficulneus A. ficulneus A. angirlosus A. angulosus +A. angulosus A. esculenlus A. esculentus A. tuberculatus A. haenkeanus A. moschatus A. moschatus A. var. genuinus spp. moschatus moschatus var. multiformis var. moschatus var. betulifolius var. betulifolius var. rugosus A. todayensis spp. tuberosus A. rugosiu (A. ruberosus) A. brevicapsulatus A. sharpei A. biankensis spp. biakensis A. manihot A. manihot A. manihol var. genuinus SQ~.mnnihot var. timorensis (cultivated)
var. tetraphyllus SQQ . retrap hy Nur A. tetraphyllus var. luzoensis (wild) var. tetraphyllus var. pungens var. pungens var. caillei Chev. (1940) A. caillei (Stevels, 1988) A. ficiclneoides Table 69.2 Taxonomic key to the species of Abehnoschusa.
Epicalyx Capsule Species
Number of Length of Shape of Caducity Relative Length Shape segments segments (mm) segments size (cm) A. 10-16 25-50 Linear. Persistent
a According to van Borssum-Waalkes (1966). b Up to 15 (Siemonsma, 1982a,b). A. X A. c mosclrarus subsp. moscharus var. moscharrcs - epicalyx segments linear (8-15 1-2 mm), hairy stem; x moscharus subsp. moscharus var. berulifolius - epicalyx segments lanceolate (17-25 2.5-5 mm), glabrous stem; . .. A. subsp. biakensis epicaljx segments lanceolate (15-20 x coriaceous capsule with long moscharusA. - 3.5-4 mm), peduncle; moschorus subsp. ruberosus - tuberous root, non-enveloping epicalyx, white or pink Rowers. d According to Stevels (1988).
have been performed on A. esculentus. The chromo- slightly different from T and Y similar to F (Josh¡ somes are short, mostly with median or submedian and Hardas, 1956). It has been suggested that primary constrictions, a few have secondary con- there are two levels of ploidy in this species, strictions. Eight chromosome types (A to H) were one with 60-70 chromosomes and the other with recorded (Datta and Naugh, 1968). The genus 120-130. Abelmoschus caillei has a very high chromo- appears 3s a regular series of polyploids with some number (n = 92-99) and is thought to be of x = 12. The genus constitutes a polyploid complex amphiploid origin from A. esculenrus (n = 62-65) and (n where varying chromosome numbers, from 14 to 97, A. nianihot = 30-34) (Siemonsma, 1982a, b). For a have been reported (Table 69.3). Basic genomes are review consult Chamer (1983). A. respectively called: (T) tuberculatw, n = 29; (M) A. nioschatw, n = 36; (F) A. ficulneus, n = 36. A synthetic diagram of the cytological relationships Early history between species is reported in Fig. 69.1. Polyploid series are found within the semi-wild ‘wide sense’ Abelmoschus species have hermaphrodite flowers. I A. (A. l species: moschafus tuberosus n = 19, A. mos- They are self-compatible and show variable levels n charus ti = 38, A. betulifo1iu.s = 140) and A. mani- of cross-fertilization. For A. esculentus 0-69 per cent hoc (A. subsp. manihot n = 30-34, A. tetraphyllus has been reported (Martin, 1983). More n = 65-66). With respect to the’two major species, precisely, the structure of the flower, in accordance A. esculenrus, n = 65 is presumed to be of allo- with Cruden’s index based on the log (polledovule), polyploid origin with E = T‘ + Y where T’ is gives mean values of 2.0 (A. esculentus, A. cailfei) i' <. Okra 353 0.i -
Table 69.3 Variation of chromosome numbers in the and 2.2 (A. manihot, A. moschatns). So the genus Abelmoschusa. breeding system is intermediate between obligate
-- ~ and facultative autogamy. However, the observed Species Numbers(2n) Authors variability in outcrossing, partly due to differences in local ecology - insects (nature, mobility and density A. escu/entus +66 Ford (1938) 72 Teshima (1933); Ugale et al. - is correlated with allopollen arrivals (Hamon and (1976); Kamalova (1977) Koechlin, 19Yla,b). 108 Datta and Naugh (1968) The geographical distribution of cultivated and wild 118 Krenke in Tischler (1931) species is shown in Fig. 69.2. 120 Krenke in Tischler (1931); Abelmoschus esculenfus Purewal and Randhawa is found all around the world from mediterranean (1947); Datta and Naugh to equatorial areas. Cultivated and wild species (1968) clearly show overlapping in Southeast Asia, which 122 Krenke in Tischler (1931) 124 Kuwada (1961, 1966) is considered as the centre of diversity. The spread 126-33 Chizaki (1934) of the other species is the result of their introduction 130 Skovsted (1935); Joshi and to America and Africa. There are two hypotheses Hardas (1953); Gadwal concernins the geographical origin of A. escu~erzrus. et al. (19fB) 131-43 Siemonsma (1981) Some authors, arguing that one putative ancestor 132 Medvedeva (1936); Roy (A. ruberculatw) is native to Uttar Pradesh (north and Jha (1958) India), suggest that the species originated from this k 132 Breslavetz ef al. (1934); Ford (1938) geographic area. Others, on the basis of ancient 144 Datta and Naugh (1968) cultivation in East Africa and the presence of the A. other putative ancestor (A.ficulrieus), suggest that the ritberculaius 58 Joshi and Hardas (1953); i 8 Kuwada (1966, 1974); area of domestication is north Egypt or Ethiopia. but Gadwal et al. (1968); A. i no definitive proof is available today. For euillei, Joshi ef al. (1973) only found in West Africa, it is difficult to suggest i Abelmoschus sp. 194 Singh and Bhatnagar (1975) an origin outside. Its origin by hybridization with l (Ghana) A. tnanihor is difficult to accept even if its presence. Abelrnosclius sp. 185-9 8 Siemonsma (1981) mentioned in the Flora of West Africa (Hutchinson 'Guinean' and Dalziel. was not recently confirmed in this A. 1958). rnutiihoi 60 Teshima (1933): Chizaki area and herbarium samples are lacking. (1934) 66 Skovsted (1935); Kamalova (1977) 68 Kuwada (1966, 1974) Recent history A. pioigetn 138 Gadwal in Joshi and Hardas (1976) The cultivation of A. esculentus is based mainly on A. reimphyllus 130 Ugale et al. (1976) traditional cultivars. Okra varieties are classified on 138 Gadwal in Joshi and Hardas the basis of plant size. pod shape and pod colour. (1976) F. Martin er al. (1981) and Hamon and van Sloten A. W. rtioscliaius 72 Skovsted (1935. 1941); (19SY) comparing a large collection of cultivars from Gadwal ci al. (1968); nl. south Europe. Asia and Africa, conclude that few, Joshi et (1971) if any, characteristics distinguished those from the coccirieus 38 Skovstcd (1935) ff. principal countries. where cultivation is very old .4. ficultieia 72 Gadwal et al. (1968): and from where the collection was drawn. Only 78 Joshi ef nl. (1974); Skovsted (1935, 1931) samples from West Africa are distinct and show wider morphological and phenological variability than in H. graudifform 38 Skovsted (1931) other areas. The global diversity is increased in West Africa by the presence another species. Meanwhile, 3. According to Siemonsma (1982b). of data show that separate cultivation and genetic 354 Okra
A. tuberosus A. crinitus
Level (2).2n = 58-72
A. ILevel (3), Zn = 120-140 I + esculenrus 1
Fig. 69.1 Cytogenic relationships between Abelmoschus species.
Fig. 69.2 Geographical distribution of Abelmoschrcs species modified from Charrier (1984).
i Okra 355
Table 69.4 Genetics of quantitative and qualitative characters in Abelmoschus esculenrusa.
~~ ~~~ 1. Quantitative characters
Characters Mode of gene action Reported by
Plant height Monogenic (tall dominant Jasim (1967) to dwarf) Plant height 4-5 groups of dominant genes Kulkarni et al. (1976) Plant height and poddplant Additive gene action Rao and Kulkarni (1977) Earliness and more numerous Dominant and over Kulkarni et al. (1976) fruits dominant (1-3 groups of dominant genes) More numerous fruits Additive gene action with Kulkarni and Thimmappaich complete dominance (1977) Low fruit number Incomplete dominance Kulkarni and Thimmappaich Days to Rower, plant height Both additive and non-additive Rao (1972) and fruitdplant gene action Yieldplant, branch number Additive gene effects Reddy et al. (1985) and plant height x Days to Rower, plant height Additive additive with Kulkarni er al. (1978) and fruitdplant epistatic action Days to Rower, yieldplant and Additive gene action Singh and Singh (1978) fruitdplant
I'I 2. Qualitative characters I Characters No. of genes Gene action
Leaf margin Monogenic Cut leaves dominant to lobed leaves Pod colour Monogenic White fruit colour is dominant to green Pod shape Digenic Angular dominant over round and epistasis nas observed Pod spininess Monogenic Spininess is dominant to non-spininess Fruit hairiness Monogenic Fruit hairiness is completely dominant over smoothness Stem colour Monogenic Purple stem colour is dominant over green
a According to Markose and Peter (1990)
barriers are enough to maintain the genetic integrity from populations chosen for their good combining of both species (Hamon and Hamon, 1992). ability. Heterosis has been reported in hybrids The selection of modern cultivars has been under- between cultivars from Malaysia and the USA taken only in a few countries (USA, Ciemson for germination percentage, precocity, flowering Spineless, Perkins Long Pods; India, Pusa Sawani, period and plant height; FI hybrid vigour in Pusa Makhmali) - a complete list of Indian varieties intraspecific crosses can be used in some combinations al. is given by Thomas et (1990). Most breeding but it is often variable and low. With respect programmes follow the crossing scheme used for to Indian accessions. strict additive gene action, autogamous plants, pedigree selection using parents sometimes lvith dominance, has been reported for I 356 Okra
the following quantitative characters: plant height. polymorphism is lacking; one reason could be the number of pods per plant, days to flower. branches very low amount of genetic diversity. We have shown per plant. General combining ability is greater than that A. esculenrus and A. caillei are monomorphic specific combining ability (SCA) for all characters. for most of the systems studied (except shikimate However, SCA is significant for 50 per cent flowering, dehydrogenase in East Africa for A. esculentus) branches per plant, fruit per branch. seed per and glutamate oxalo-acetate dehydrogenase (for fruit, diameter and length of fruits. Yield per A. caillei). These two species exhibit ver)' similar plant has a significant positive association with patterns for most studied isozymic systems except the number of pods, number of nodes and plant malate dehydrogenase, phospho-glucose-isomerase height. Simple inherited characters are rare. these and isocitric acid dehydrogenase. Preliminary results affect particularly the colour of different organs or indicate that A. moschatits and A. manilior are more pod characters. Light red petiole, petal blotch, petal polymorphic. venation, pod colour (multiallellism) show simple Seed conservation is certainly the most convenient monogenic inheritance. Fruit hairiness. leaf lobing way to preserve okra genetic resources. Unfortu- (with incomplete dominance) are also monofactorial, nately, seeds are known to have a short longevity. pod shape (angular/rou,nd) is digenic with angular J. A. Martin et al. (1981) showed that low temperature dominant. In Table 69.4 a summary of the genetics (5 "C) and low moisture content permit conservation of quantitative and qualitative characters is reported for II years. Low oxygen and high content carbon (Markose and Peter, 1990). dioxide levels maintained seed viability by reducing Okra, like other Malvaceae, is susceptible to a metabolic activity. large variety of pests and diseases - insects. fungi. nematodes and viruses. In most cases insects and fungi can be controlled by suitable treatment twice Prospects a week. Nematodes (Meloidogyne) can be controlled by chemical treatment or prior planting of Panicum With respect to improved varieties, breeders produced maximum for one year. No control is available for several years ago the well-known varieties Clemson viruses which may completely destroy A. esculenrus Spineless and Pusa Sawani, which have not been plants. The main fungal pests are: (1) prelpost replaced. It seems that selection for earliness and yield emergence: Fusarium solani, Phytophthora parasitica, has been replaced by the search for virus-resistant Pythium; (2) on leaves: Cercospora mcìlayensis and varieties. The introduction of genes from wild species, C. abelmoschi, (3) on flowers and fruit: Fusarium as in any other genus, is very difficult and needs a solani, Rhizoctonia solani. The most serious diseases good knowledge of sterility levels and the ways to of okra are viruses: the yellow vein mosaic virus overcome them. (YVMV) in India and the okra leaf curl (OLC) in The International Board of Plant Genetic Re- Africa. Both are transmitted by a small white fly sources organized a workshop in New Delhi. India, A. (Bemisia tabaci). Abelmoschus caillei and letra- in 1990 in order to produce a synthesis of current phyllus seem more tolerant of these viruses than other scientific knowledge on okra and to promote the species. Hybridization with A. esculenrus has been formation of an Abelmoschus network (IBPGR, carried out through a backcross breeding programme 1991). The main conclusions were that, compared (Jambhale and Nerkar, 1981). to some other crops, very little work has been The morphoIogical diversity of the cultivated undertaken on okra and that the major part which species is very low, except in West Africa. The has been done concerns A. esculentus. Among the relatively simple inheritance of colour characters recommendations were that: and pod shape, the breeding system, the local procedure for the management of varieties, could 1. Taxonomy needs clarification especially for the (A. A. explain the rapid fixation of a large number of two broad species manihot and moschatus) different phenotypes. An important question is, what and A. tuberculnrus is the real level of the genetic diversity of such an 2. Phylogenetic and cytological relationships between amphiploid species? Research on okra isoenzymic species remain unclear not only for wild but also Okra 357
(A. A. for cultivated species esculentus and cuillei). Martin, J. A., Senn, T. L., Sheklon, B. J. and Crawford, A. J. H. (1981) Response of seeds to moisture content Despite the fact that esculentus is the most studied okra species, no one could really say if the different and srorage temperature. Proc. Amer. Soc. Hort, Sci. 75,4904. chromosome numbers encountered are a reality or hlartin, F. W. (1983) Natural outcrossing of okra in Puerto due to sampling errors. A Rico. J. Agric. Univ. of Puerto Rico 67, 50-2. 3. new standardized descriptor list will be proposed. Martin. F. W., Rhodes, A. M., Ortiz, M. and Diaz, F. 4. The core collection concept which was first applied (1981) \'ariation in okra. Ercphyrica 30(3), 697-705. to cultivated varieties must be applied to wild forms. Siemonsma, Y. (1982a) La culture du gombo (Abelnioschus spp.) Itgume fruit tropical avec référence spéciale ;i la C6te d'Ivoire. Thesis, University of Wageningen, The Netherlands. References Siemonsma, Y. (1982b) West African okra. Morphological and cytological indications for the existence of a natural Borssum-Waalkes, J. van (1966) Malaysian Malvaceae amphiploid of Abehoschus esculenrus (L.) Moench and revised. Blutnea (l), 1-251. 14 A. r?ianihor (L.) Medikus. Euphpfica 31(1). 241-52. Charrier, A. (1954) Genetic resources the genus J. of Stevels, M. C. (1988) Une nouvelle combinaison dans Abelmoschus Med. (Okra). International Board for Abelmoschus Medik. (Malvaceae), un gombo d'Afrique Plant Genetic Resources, Rome, Italy. de l'Ouest et Centrale. Bull. Mus. natn. Hist. Nat. Paris. Chevalier, A. (1940) L'origine. la culture et les usages de 4th 10, section B, 137-44. scries, S.,2, cinq Hibiscus de la section Abelmoschus. Rev. Bot. appl. Thomas, T. A., Bisht, I. Bhala, S., Sapra, R. L. and 319-28.402-19. 20, Rhana, R. S. (1990) Colalogue on okra germplasm. Datta, P. C. and Naugh,A. (1968) A few strains of NBPGMCAR, New Delhi. India. Abelmoschus esculentus L. Moench. Their caryological study and relation to phylogeny and organ development. Beitr. Biol. Pflanz. 45, 113-26. Hamon, S. and Hamon, P. (1992) Future prospects of the genetic integrity of two species of okra (Abelmoschus esciilenrus and A. caille¡) cultivated in Wcst Africa. O~phyii~a58, 101-1 I. Hamon, S. and Koechlin, J. (1991a) The reproductive biology of okra. Study of the breeding system in four Abelmoschus species. Euphyrica 53, 41-8. Hamon, S. and Koechlin, J. (1991h) Self-fertilization kinetics in the cultivated okra (Abelmoschus esculenrus), and consequences for breeding. Euphytica 53, 49-55. Hamon, S. and van Sloten, D. H. (1989) Characterization and evaluation of okra. In A. D. H. Brown and O. Frankel (eds.) The use of crop genetic resources. Cambridge pp. 173-96. Hochreutiner, B. P. G. (1924) Genres nouveaux et genres discutes de la famille des malvacées. Catidollea 2, 79-90. Hutchinson, J. and Dalziel, J. M. (1958) Flora of West Africa l(2). 343-8. IBPCR (1991) Internatl. Crop Network Series 5 Report on Okru G'etzcric Resources International Board for Plant Genetic Resources. Jambhale and Nerkar (1981) Inheritance of resistance to okra jellow vein mosaic disease in interspecific crosses of Abelmoschus. Theor. Appl. Genet. 313-16. A. 60, Joshi, B. and Hardas, M. W. (1956) Alloploid nature of okra (Abelmoschus esculentus). Nature 178, 1190. Markose, B. L. and Peter, K. V. (1990) Review of research on vegetables and tuber crops -okra. Kerala Agric. Univ. Mannuthy, India. Technical Bullerin 16, 109. ORSTOM i RESSOURCES GENETIQUES ET AMELIORATION DES PLANTES TROPICALES 4 B.P. 5045 - I 34032 MONTPELLIER CEDEX
Evolution of Crop Plants
Second Edition
Edited by
J. Smartt School of Biological Sciences University of Southampton
and
N. W. Simmonds Formerly Edinburgh School of Agriculture Edinburgh
CD e s 9 .... F ... M ... O ...... NOC ..... Le Directeur,
NOV. foRSToM\ 2 7 1995 Montpellier Longman Scientific & Technical Longman Group UK Limited Longman House. Burnt Mill. Harlow Essex CM2O ?JE, England and Associored Compuni¿s ihroliglio~rrrhe world
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First published 1976. Second edition 1995 British Library Cataloguing in Publication Data A catalogue.entry for this title is available from the British Library. ISBN 0-582-086434
Library of Congress Cataloging-in-Publication data Evolution of crop plants Iedited by J. Smartt and N. W. Simmonds. - 2nd ed. p. cm. Includes bibliographical references and index. ISBN 0-470-23372-9 J. 1. Crops-Evolution. I. Smartt. II. Simmonds. N. W. (Norman Willison), 1922- . SB106.074E96 1995 6314~70 91-25791 CIP
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