Seed Morphobiometry of Wild and Cultivated Taxa of Phaseolus L. (Fabaceae)

Abstract

A morphobiometric analysis of seeds of Phaseolus L. from 50 populations belonging to 31 wild and cultivated
taxa was carried out. Based on the outcome of the study an identifi cation key was developed comprising 25
morphotypes of which 23 related to individual taxa [P. angustissimus Gray, P. fi lifomis Benth., P. acutifolius Gray
var. latifolius Freeman, P. lunatus L. var. sylvester Baudet, P. polyanthus Greenm., P. lunatus L. var. lunatus
cv.-gr. “Sieva”, P. lunatus L. var. lunatus cv.-gr. “Big Lima”, P. lunatus L. var. lunatus cv.-gr. “Potato”,
P. maculatus Scheele, P. lunatus L., P. microcarpus Mart., P. leptostachyus Benth. var. leptostachyus,
P. grayanus Woot. & Standl., P. vulgaris L. var. aborigeneus (Burk.) Baudet, P. marechalii Delgado, P. vulgaris
L. var. vulgaris, P. ritensis Jones, P. polystachios (L.) Britt., Sterns & Pogg. var. polystachios, P. hintonii
Delgado, P. paucifl orus Don, P. parvulus Greene, P. plurifl orus Maréchal, Mascherpa & Stainer, P. micranthus
Hook. & Arn.) and two that refer to several taxa (P. vulgaris morphotype with P. vulgaris L., P. coccineus L.,
P. glabellus Piper, P. oligospermus Piper and P. acutifolius var. tenuifolius morphotype with P. acutifolius
Gray var. tenuifolius (Woot. & Standl.) Gray, P. acutifolius Gray var. acutifolius, P. xanthotrychus Piper,
P. zimapanensis (Delgado) Jaaska). The different patterns of seminal tegument allowed 31 taxa to cluster into
three groups: (1) Phaseolus angustissimus Gray group (wrinkled seed coat) with two morphotypes, (2) Phaseolus
lunatus L. group (smooth tegument with striae) with ten morphotypes and (3) Phaseolus vulgaris L. group
(smooth tegument without striae) with 13 morphotypes. All the taxa exhibited uniformity in size and variability
in tegument colour of seeds irrespective of the source of population and the type of habitat. Characterization of
taxa into defi nite morphotypes and the groups could be useful for biosystematic investigations and the markerbased
genetic selection approaches in this important leguminous crop.