Genetic erosion and Genetic erosion and extinction threat of extinction threat of the the

old world cottons, old world cottons, GossypiumGossypium L L..

Vojtěch HolubecVojtěch HolubecDept. of Gene BankDept. of Gene Bank

Research Institute of Crop Production,Research Institute of Crop Production,Prague – Ruzyně, Czech RepublicPrague – Ruzyně, Czech Republic

Why? and AimWhy? and Aim

a case studya case study alarming situation alarming situation

already in the pastalready in the past IPGRI internshipIPGRI internship

Aim: to assess the needs for collection Aim: to assess the needs for collection and conservation of wild African and and conservation of wild African and Arabian cottonsArabian cottons

IntroductionIntroduction

Wild species of Wild species of GossypiumGossypium occupy occupy both Americas, Africa, Asia (Arabia) both Americas, Africa, Asia (Arabia) and Australiaand Australia

While American and Australian While American and Australian species are quite well known, there species are quite well known, there was a very little knowledge on was a very little knowledge on African and Arabian spp. African and Arabian spp.

It was expected, those localities/spp. It was expected, those localities/spp. could have been endangered could have been endangered

Material and methodsMaterial and methods Important Important herbaria herbaria have been visitedhave been visited: K, BM, P, BR, COI, : K, BM, P, BR, COI,

LISCLISC,, MO, NA, NY, US MO, NA, NY, US DData were recorded into a dbf file. ata were recorded into a dbf file. Revision Revision of species of species CCollection sites were localized ollection sites were localized ((geographical gazetteergeographical gazetteer)) SSpecies distribution was plotted pecies distribution was plotted toto the maps in the Miller's the maps in the Miller's

oblate stereographic projection in the scale 1:50 mil. (Miller, oblate stereographic projection in the scale 1:50 mil. (Miller, 1953). 1953).

"The vegetation map of Africa" was used to match the "The vegetation map of Africa" was used to match the species distribution with various mapping units. The species distribution with various mapping units. The borders of the mapping phytochoria were digitized and borders of the mapping phytochoria were digitized and drawn into the distribution maps. The program and maps drawn into the distribution maps. The program and maps were generated at the Computing Center of Texas A & M were generated at the Computing Center of Texas A & M University. University.

Number of collected herbarium records of Gossypium and Gossypioides species of Africa and Arabia in visited herbariaHerbarium BM BR COI K LISC MO NA NY P US pf SumNo. of exsiccata 74 113 39 251 89 81 61 51 69 46 22 905

Results and discussionResults and discussion 1. Taxonomy of African and Arabian species of cotton1. Taxonomy of African and Arabian species of cotton Taxonomic treatment of the genus Taxonomic treatment of the genus GossypiumGossypium was was

accepted as was proposed by Fryxell (1979) with the accepted as was proposed by Fryxell (1979) with the following changes:following changes:

- - Gossypium herbaceumGossypium herbaceum var. var. africanumafricanum was accepted at was accepted at the subspecies level as proposed by Mauer (1954)the subspecies level as proposed by Mauer (1954)

- subdivision of - subdivision of G.somalenseG.somalense into species into species G.somalense, G.somalense, G.benadirense G.benadirense andand G.bricchettii G.bricchettii was adopted as suggested was adopted as suggested by Vollesen (1987)by Vollesen (1987)

- - G.trifurcatumG.trifurcatum described by Vollesen (1987) was included described by Vollesen (1987) was included in the subgenus in the subgenus GossypiumGossypium..

KKeys for eys for determination determination of Africaof Africann and Arabia and Arabiann species were species were designed.designed.

1.3. The species concept1.3. The species concept (Africa, Arabia) (Africa, Arabia)subgenus subgenus SturtiaSturtia (R.Brown) Todaro (R.Brown) Todaro genome genome section section HibiscoideaHibiscoidea Todaro Todaro

Gossypium triphyllumGossypium triphyllum (Harv. ex Harv. (Harv. ex Harv. Sonder) Sonder) HoHochr............B2chr............B2subgenus subgenus GossypiumGossypium

Gossypium trifurcatumGossypium trifurcatum Vollesen...........................................? Vollesen...........................................? section section GossypiumGossypium

subsection subsection GossypiumGossypiumGossypium arboreumGossypium arboreum L.......................................................A2 L.......................................................A2Gossypium herbaceumGossypium herbaceum L.....................................................A1 L.....................................................A1Gossypium herbaceumGossypium herbaceum L. ssp. L. ssp. africanumafricanum (Watt) Mauer..... (Watt) Mauer.............A1......A1

subsection subsection AnomalaAnomala Todaro TodaroGossypium anomalumGossypium anomalum Wawr. ex Wawr. Wawr. ex Wawr. Peyr.................. Peyr..............................B1..B1Gossypium capitis-viridisGossypium capitis-viridis Mauer... Mauer.............................................B3......................................B3

section section PseudopambakPseudopambak Prokhanov Prokhanov subsection subsection PseudopambakPseudopambak

GossypiumGossypium stocksiistocksii Mast. in Hook..... Mast. in Hook................................................E1.............................E1Gossypium somalenseGossypium somalense (Gürke) J.B.Hutch... (Gürke) J.B.Hutch................................E2...........................E2Gossypium benadirenseGossypium benadirense Mattei.............................................E Mattei.............................................EGossypium bricchettiiGossypium bricchettii Ulbrich...............................................E Ulbrich...............................................EGossypium incanumGossypium incanum (Schwartz) Hillc.....................................E4 (Schwartz) Hillc.....................................E4Gossypium areysianumGossypium areysianum Defl.................................................E3 Defl.................................................E3

subsection subsection LongilobaLongiloba Fryxell FryxellGossypium longicalyxGossypium longicalyx J.B.Hutch. J.B.Hutch. Lee ..... Lee .......................................F1..........................F1

subgenus subgenus KarpasKarpasGossypium hirsutumGossypium hirsutum L.....................................................(AD)1 L.....................................................(AD)1Gossypium barbadenseGossypium barbadense ..............................................(..............................................(AD)2AD)2

Cultivated Cultivated species growing species growing wildly and wildly and primitive primitive landraces are landraces are distributed distributed throughout the throughout the tropical belt tropical belt except for the except for the high mountains. high mountains.

They occupy They occupy more mesophytic more mesophytic up to very humid up to very humid habitats.habitats.

2. Distribution of species of 2. Distribution of species of GossypiumGossypium

Wild species of Wild species of GossypiumGossypium are are restricted in their restricted in their distribution to the distribution to the tropical belt between tropical belt between latitudes 20latitudes 2000N and N and 252500S. S.

They are confined to They are confined to semidesert regions semidesert regions so that their so that their distribution is distribution is disjunct with hyatus disjunct with hyatus in Zaire and north in Zaire and north Zambezian basins. Zambezian basins.

G. longicalyxG. longicalyx and and partly partly G. herbaceum G. herbaceum sspssp. africanum. africanum tend tend to occupy slightly to occupy slightly more mesophytic more mesophytic habitats.habitats.

The Sahel regional transition zone:The Sahel regional transition zone: 54a54a Sahel semidesert grassland and Sahel semidesert grassland and

shrublandshrubland 4343 Sahel Acacia wooded grassland and Sahel Acacia wooded grassland and

Acacia deciduous bushlandAcacia deciduous bushlandThe Somalia-Masai regional center of endemism:The Somalia-Masai regional center of endemism: 54b54b Somalia-Masai semidesert grassland Somalia-Masai semidesert grassland

and shrublandand shrubland 4242 Somalia-Masai Acacia-Commiphora Somalia-Masai Acacia-Commiphora

deciduous bushland and thicketdeciduous bushland and thicketThe Karoo-Namib regional center of endemism and The Karoo-Namib regional center of endemism and

transition to Kalahari:transition to Kalahari: 74 74 The Namib desertThe Namib desert 51 51 Bushy Karoo shrublandBushy Karoo shrubland 3636 Transition from Colophospermum Transition from Colophospermum

mopane scrub woodland to Karoo-Namib mopane scrub woodland to Karoo-Namib shrublandshrubland

5656 Kalahari/Karoo-Namib transitionKalahari/Karoo-Namib transitionThe Zambezian regional center of endemismThe Zambezian regional center of endemism 2828 Colophospermum mopane woodland Colophospermum mopane woodland

and scrub woodlandand scrub woodland 2929 Zambezian undifferentiated woodlandsZambezian undifferentiated woodlands

Phytochoria and mapping units after White (1983) in which Phytochoria and mapping units after White (1983) in which African species of African species of GossypiumGossypium occur. occur.

2.2. The Somalia-Masai Regional Center of Endemism2.2. The Somalia-Masai Regional Center of Endemism 1. South-eastern distribution of . somalense1. South-eastern distribution of . somalense 2. Entire distribution of G. benadirense2. Entire distribution of G. benadirense 3. Entire distribution of G. bricchettii3. Entire distribution of G. bricchettii 4. African distribution of G. stocksii4. African distribution of G. stocksii 5. African distribution of G. incanum5. African distribution of G. incanum 6. Southern distribution of G. longicalyx6. Southern distribution of G. longicalyx 7. Distribution of G. trifurcatum7. Distribution of G. trifurcatum2.5. Southern Arabia2.5. Southern Arabia 1. entire distribution of G. areysianum1. entire distribution of G. areysianum 2. distribution of G. incanum2. distribution of G. incanum 3. part of the distribution of G. stocksii3. part of the distribution of G. stocksii

G. benadirense grows in Upper Giuba in Somalia and southern Ethiopia and in lower Uebi Scebelli on limestone rocks as G. somalense.

G. bricchettii distribution represents an eastern extension of area of G. somalense (northern Mudugh and south of the Nogal Valley, Somalia). No evidence of distribution are known from Ethiopia although it may grow in eastern Ogaden The sites were described as plains or limestone slopes overgrazed limestone-gypsum pavement with grey soil or around gypseous drainage hollows. The plant cover: Salvadorean, Acacia-Commiphora open bushland. Gillet, Hemming and Watson (#21941) reported widespread distribution in the western part of central Somalia.

G. G. llongicalyxongicalyx

The The distribution seems to be disjunct. distribution seems to be disjunct. Great Ruaha ValleyGreat Ruaha Valley, Tanzania., Tanzania. Only one specimen were Only one specimen were collected ca 1900 km collected ca 1900 km NN in Meshra el Zeraf in Sudan. in Meshra el Zeraf in Sudan.reported mostly from reported mostly from Commiphora-CombretumCommiphora-Combretum zone zone between 700-900 m growing in open or closed bushland of between 700-900 m growing in open or closed bushland of CombretumCombretum sp, sp, TerminaliaTerminalia stuhlmannii, Acacia nigrescnesstuhlmannii, Acacia nigrescnes and and Delonix elataDelonix elata or from or from Acacia seyal-A. meliferaAcacia seyal-A. melifera community from the surroundings of Nondwa. It grows community from the surroundings of Nondwa. It grows very local and uncommon.very local and uncommon.The northern Sudan locality belongs to the Sudanian The northern Sudan locality belongs to the Sudanian center of endemism, to the mapping unit 61, Edaphic center of endemism, to the mapping unit 61, Edaphic grasslands of the Upper Nile basin (White, 1983). grasslands of the Upper Nile basin (White, 1983). It grows most likely on black clay soils where rainfall is It grows most likely on black clay soils where rainfall is about 750 mm (Knight 1949). about 750 mm (Knight 1949). The collection has never been repeated since the Brown's The collection has never been repeated since the Brown's (s.n., 1910) original one.(s.n., 1910) original one.

3. Priority Regions for Collecting of 3. Priority Regions for Collecting of Cotton GermplasmCotton Germplasm

1. Niger, Air Mts., and generally northern Sahel, species: G. anomalum, G. somalense, endangered by desertification, only a few collections known

2. Yemen, Aden region and SE coast;species: G. areysianum, G. incanum; very limited in distribution, may be endangered

3. Somalia, central part; species: G. benadirense, G. bricchettii, G. somalense, G. stocksii, G. incanum, G. trifurcatum

species not in cultivation and/or with limited distribution

4. Sudan, Meshra el Zerav; species: G. longicalyx;

only one specimen reported in 1910

5. Somalia, Ethiopia, Kenya, frontier region, Upper Giuba; species: G. benadirense (not in cultivation), G. somalense

6 Cape Verde Islands, Sao Antao, Sao Tiago; species: G. capitis-viridis, distribution very limited, endangered, very rare

7. Tanzania, Iringa: Nondwa and Great Ruaha valley; species: G. longicalyx, distribution very limited.

ConclusionsConclusions Estimated species distribution was corrected by Estimated species distribution was corrected by

plotting of exact dataplotting of exact data Distribution most of species matches with Distribution most of species matches with

certain phytochoria/mapping units of certain phytochoria/mapping units of Vegetation map of AfricaVegetation map of Africa

Some species are very restricted: Some species are very restricted: – The distribution of The distribution of G.longicalyxG.longicalyx is restricted to a is restricted to a

small area of central Tanzaniasmall area of central Tanzania and S Sudan and S Sudan– G.incanumG.incanum occupies the coastal strip of S occupies the coastal strip of S

Yemen, one specimen was found in the Nogal Yemen, one specimen was found in the Nogal Valley, Somalia (Hemming & Watson 3156, K)Valley, Somalia (Hemming & Watson 3156, K)

ThThee coincidence coincidence with veg. map with veg. map suggests a suggests a possibility to predict their further distributionpossibility to predict their further distribution

The distribution of wild species is restricted The distribution of wild species is restricted mostly to arid habitats, which are generally mostly to arid habitats, which are generally endangered by desertification and overgrazingendangered by desertification and overgrazing

The occurrance of species within the The occurrance of species within the distribution area is rather rare or very raredistribution area is rather rare or very rare

The distribution restricted species are The distribution restricted species are known (have been collected) from a few or known (have been collected) from a few or only one localityonly one locality

Presence of Presence of G.incanumG.incanum and and G.longicalyxG.longicalyx in in germplasm collections is based on one germplasm collections is based on one sample only, others, if present, are sample only, others, if present, are duplicationsduplications

The small species The small species G.benadirense, G.benadirense, G.bricchettiiG.bricchettii and and G.trifurcatumG.trifurcatum are most are most likely not available in germplasm likely not available in germplasm collectionscollections

There is a serious danger of extinction of all There is a serious danger of extinction of all the distribution restricted speciesthe distribution restricted species

Collecting of all African and Arabian Collecting of all African and Arabian species should be considered for ex situ species should be considered for ex situ conservation as an international priorityconservation as an international priority

In situIn situ conservation at least of restricted conservation at least of restricted species should be considered if it is not late species should be considered if it is not late at allat all

A compiled vocabulary of vernacular A compiled vocabulary of vernacular cotton names should help in collectingcotton names should help in collecting

AcknowledgementsAcknowledgements

I would like thank to I would like thank to DrDr.J.T.J.Trevor revor WilliamsWilliams, , IPGRIIPGRI And to And to Drs. R.J.Kohel, Drs. R.J.Kohel, PP.A.Fryxell and A.E.Percival.A.Fryxell and A.E.Percival, , USDA, SPA, College Station, TX USDA, SPA, College Station, TX