Agriculture Reference
In-Depth Information
Tab l e 3 . 2
Legumes native to Madagascar, most of which are endemic. Data from Du Puy et al. (2002)
Tribe
Genera
Species
Comments
Caesalpinieae
7
17
Includes one sp. of
Erythrophleum
, nodulated (?)
Cassieae
7
30
Includes 9 spp. of
Chamaecrista
, all nodulated (?)
Cercideae
2
17
Detarieae
5
16
Ingeae
2
45
Albizia
and
Viguieranthus
Mimoseae
10
80
Includes 31
Mimosa
spp.
Abreae
1
7
Aeschynomeneae
8
27
Included in Dalbergioid clade in Chapter 1
Crotalarieae
2
42
Includes 41
Crotalaria
spp.
Dalbergieae
1
25
Desmodieae
5
18
Genisteae
1
3
Indigofereae
4
64
Includes 44
Indigofera
spp.
Millettieae
10
71
Includes 27
Tephrosia
spp.
Phaseoleae
19
61
Sesbanieae
1
3
Sophoreae
8
17
A mix of nod- and non-nod genera
Swartzieae
1
2
Non-nodulating
Trifolieae
1
1
last 10 Ma; on each occasion new species developed within Madagascar (B.D. Schrire,
personal communication). This genus, together with
Tephrosia
and
Crotalaria
,bothof
which are shrubs or herbs, have species that can grow on very nutrient-poor soils.
Crotalaria
species are known to nodulate with a range of
-Proteobacteria (Chapters 1
and 4). In view of the fact that Malagassy species occur on almost all types of soil and
habitat (Du Puy et al., 2002), it would be interesting to see if particular endosymbionts
are associated with certain soil conditions as has been suggested for the related genus
Lotononis
(Yates et al., 2007). Seven different genera of
-Proteobacteria have
been isolated from nodules of
Dalbergia
spp. from Madagascar (Rasolomampianina
et al., 2005).
Erythrophleum couminga
(Caesalpinioideae) only occurs in the western
coastal region of Madagascar and is thought to be closely related to the East African
species,
E. suaveolens
, known to be nodulated. The big puzzle concerns
Mimosa
, which
has 31 species in Madagascar, but which is very poorly represented in Africa, with at
most 4 native species (M. Simon, personal communication), including
M. busseana
from
Tanzania and Mozambique (Lock, 1989), other species being introduced. There are 5
species in Asia, with the remaining nearly 500 species from South America (M. Simon,
personal communication). How the genus arrived in Madagascar is very unclear, but
it clearly found conditions to its liking as it occurs throughout the island. Twelve new
species are described in Du Puy et al. (2002). How many arrivals and from where
they came is likely to remain unclear until a detailed molecular analysis is carried out.
At least one Madagascan species, plus species from Nepal, introductions from Viet-
nam, Australia, Taiwan and its native Brazil, are nodulated by
-and
-Proteobacteria (Elliott
et al., 2007a) (Chapter 4).
