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SUMMARYGene Ecological studies on some species of Leguminosae : This study is devoted to survey seeds of sixty three taxa of genus Trifolium (Leguminosae) belonging to five sections; lot idea, Mistyllus, Vesicaria, Chornosomium and Trifolium are discussed. Seeds of these examined taxa were either collected from Egypt or received form gene bank in from various botanic grardons in America Germany and Ethiopia and this bank was collected this seeds form different Europian American and African countries. This study aims to revealing further seed characters, which may be very useful in further distinction of the taxa studied and to define those characters, which are likely to be of most use in the systematic of the subfamily. It also constitutes an atlas An artificial key has been constructed based on exomorphological surface scan characteristic and endomorphological aspects of the seeds of the taxa studied, in order to differentiate between these taxa. In addition the data produced from seed protein elThe different seed exomorphological and endomorphological attributes of the studied taxa are presented in the form of cumulative tables, photomicrograph and plates, as well as photographic pictures of seed protein electrophoretic profiles.This work revealed many points, which might be of taxonomic interest:1- The variation in the seed shape represents a useful criterion in taxonomic distinction among the taxa studied.2- The shape of Trifolium seed can vary with maturity based on crowding the seed on plant.3- In this work there is a great variation in seed shapes of the taxa examined. Seed shapes of Trifolium were divided into different shape:Rounded (6 taxa) in T. hybridum, Globular in T. arvense. Subglobular in T, amabile, Ovoid (22 taxa) in T.africanum. Ovoid oblong in T.burchellianum Elliptical oblong in T. decorum, T, bilineatum .Ovoid to reniform in T. Semipilosum, Reniform (16 taxa) in 4- The study of colour of seeds are frequently inconsistent attributes, and they are of minor taxonomic significance, they here, stand diagnostic for some of the studied taxa. In this work the colour of seeds were recorded as yellow, brown, red and black,5- The variation in the seed size of the taxa were examined its useful as a key in taxonomic distinction among the taxa studied seed size of Trifolium were divided into very small seeds (7 taxa) eg T. arvense) and small seeds (48 taxa) eg T. hirtum.6- Seed surface as viewed under light Microscope L) (texture) the seed surface my be smooth (18 taxa), e.g. T. masaiense smooth – dull (25 taxa), e.g T. ombiguum smooth to mimutely tuberculate (T. hybridum) and mimutely tuberculate (11 taxa), e.g. T.quart7- The shape of hilum appears to be important in the seed identification and to separate this taxa, this shape of hilum is differentiated into leveled (4 taxa) eg T. africanum, slightly sunken (6 taxa) eg T. amabile and sunken (45 taxa) eg T. isthmocarpum8- The testa as viewed under Scanning Electron Microscope SEM, revealed seven basic sculpturing patterns namely: papillose eg T. multinerve Numerous small mounds with low papillose eg T.Cernum Mintely irregular tuberculate in T. decorum lophate in T. anguIntegrated forms within the basic patterns were also recorded. The distribution of these sculpturing patterns presented an indispensable criterion for delimitation of the taxa studied, primarily at the species level and sometimes at the generic level. But9- The taxonomic relationships between these sixty-three taxa are evaluated, based on numerical analysis.10- The dendrogram, resulted from the hierarchical cluster analysis of SDS-PAGE profiles of seed proteins conform, with some restrictions, to the splitting of genus Trifolium into sections, on the basis of morphological characters by Zohary and Heller (1911- The grouping of the two taxa, T. campestre and T. dubium, belonging to section Chronosemium, with T. resupinatum and T. tomentosum, belonging to section Vesicaria, reveal a close affinity between the two sections specially all taxa belonging them clus12- The result shows the subsectional delimitation of section lotoidea and section Trifolium as proposed by Zohary Heller (1984) should be examined.
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