The results of this study show that the material belongs to three ploidy levels and nine species: three diploid species (2n=2x=14), T. urartu Thum. ex Gandil., Triticum monococcum L. and T. boeoticum with subsp. boeoticum Boiss. ex Hausskn. and subsp. thaoudar (Reut. ex Hausskn.) Schiem.; four tetraploid species (2n=4x=28), T. dicoccum (Schrank.) Schubl., T. dicoccoides (Korn. ex Aschers. et Graebn.) Thell., T. turgidum L. and T. durum Desf.; and two hexaploid species (2n=6x=42) T. aestivum L. and T. compacturn Host. The results of morphological surveys are presented in Table 3 and the spike characters of the species recognized are illustrated in Fig. 2a, b.

Based on the results of this study the genus Triticurn in Iran contains nine species and two subspecies mainly occurring in the Zagros Mountains (Fig. 1). The results of this study are not completely in accordance with those of Boissier (1885) who reported three, Parsa (1954) and Bor (1970) who reported ten, respectively, and Mobayen (1980) who reported nine Triticum species in Iran (Table 1). Our results show that the herbarium materials examined belong to six species (Table 2).

Three species (T. orientale Percival, T. polonicum L. and T. spelta L.) recorded by Bor (1970) were not recognized in this study. Bor mentioned only one locality for each of T. orientale and T. polonicum: "Khorasan, Sykes" and "Azarb., Khoy, Coll. Ign. 358" respectively. In addition, he reported T. spelta from Iran based on one doubtful report: "Found in the Bakhtiari country from Shahr-e Kord to Shanseabad and Buldaji, Kuckuck (Wheat Inf Serv No.9,1959)". Our expedition in the area did not find this species there; in addition it should be mentioned that the correct name for Shanseabad is Shamsabad, which is a village near Buldaji. Our study revealed two new species, T. urartu and T. compactum for Iran. We found the latter species as growing in the wheat fields (T. aestivum), probably arising as comtaminants of the seeds of T. aestivum.

While there is a trend among more recent Triticum students to lump the taxa within each ploidy level (see Mac Key 1988 and Van Slageren 1994), the older researchers were more inclined split them (Flaksberger 1935; Schiemann 1948; Jakubziner 1958;Bowden 1959; Morris and Sears 1967). Following the morphological results of this study and also the presence of gene flow barriers among diploid Triticum species reported by Filatenko et al. (2001), the diploid species T. urartu, T. monococcum and T. boeoticum are treated as distinct species in this study.

Key to the species of the genus Triticum in Iran.
1- Non- free threshing, rachis tough or fragile (broken easily) and ciliate:
    2- Spikelet with 1-2 seeds, narrow and falling; nodes of stem hairy or ciliate, violet or brown:
    3- Lemma of the uppermost floret of each spikelet 1-toothed and awnless .............   T. urartu
    3- Lemma of all florets untoothed and with 1-2 awns   
    4- Lemma with 1 awn    ............. T. monococcum   
    4- Lemma with two awns
    5- Lemma with unequal awns .   .............. T. boeoticum subsp. thaoudar
    5- Lemma with unequal awns. .   ............... T. boeoticum subsp. boeoticum

2- Spikelets with 2-4 seeds, broad and non-falling; nodes of stem ciliate, yellow or straw colored:
  6- Rachis tough; lemma of uppermost spikelet usually with 1 awn (rarely with 2 awns) and that of lowermost spikelet with 1 awn ...................... T. dicoccum
  6- Rachis fragile; lemmas always with 2 awns .......... T. dicoccoides
1- Free threshing; rachis tough and ciliate:
   7- Spike quadrate in cross section; spikelets compacted in the spike; nodes of stem glabrous     
  8- Endosperm flinty; leaf glabrous (rarely hairy); rachis-long ciliate, spike 9.3-21.c ..........T. durum
   8- Endosperm mealy; leaf hairy; rachis shortly ciliate; spike 10.2-14.7 cm.................... T. compactum
  7- Spike elliptic or ovate in cross section;spikelets more or less loosely arranged in the spike; nodes of stem hairy or ciliate:
  9- Spike ovoid, 8.7-23.1 cm; glume keeled from base to apex............ T. turgidum
  9- Spike obtriangular, 9.2-25.8 cm; glume keeled in the upper half only ................... T. aestivum

Acknowledgements

The authors would like to express the greatest thanks to Professor Clive Stace for his valuable guidance and also for revising and correction of this paper. Also we would like to thank Mr. Iraj Mehregan for the drawings.