| Summary: | Early root traits and allometrics of wheat are important for competition and use of resources. They are under-utilized in research and un-explored in many ancient wheats. This is especially true for the rhizosheath emerging from root-soil interactions. We investigated root morphology, root/shoot relations and the amount of rhizosheath of four tetrapoid wheat seedlings (30 days after emergence): the italian landrace Saragolle Lucana and modern varieties Creso, Simeto and Ciclope, and tested the hypothesis that inoculation with <i>Trichoderma harzianum</i> T-22 (T-22) enhances rhizosheath formation and affects wheat varieties differently. Overall growth of non-inoculated plants showed different patterns in wheat varieties, with Saragolle and Ciclope at the two extremes: Saragolle invests in shoot rather than root mass, and in the occupation of space with highest (<i>p</i> < 0.05) shoot height to the uppermost internode (5.02 cm) and length-to-mass shoot (97.8 cm g<sup>−1</sup>) and root (more than 140 m g<sup>−1</sup>) ratios. This may be interpreted as maximizing competition for light but also as a compensation for low shoot efficiency due to the lowest (<i>p</i> < 0.05) recorded values of optically-measured chlorophyll content index (22.8). Ciclope invests in biomass with highest shoot (0.06 g) and root (0.04 g) mass and a thicker root system (average diameter 0.34 mm vs. 0.29 in Saragolle) as well as a highest root/shoot ratio (0.95 g g<sup>−1</sup> vs. 0.54 in Saragolle). Rhizosheath mass ranged between 22.14 times that of shoot mass in Ciclope and 43.40 in Saragolle (different for <i>p</i> < 0.05). Inoculation with <i>Trichoderma</i> increased the amount of rhizosheath from 9.4% in Ciclope to 36.1% in Simeto and modified root architecture in this variety more than in others. Ours are the first data on roots and seedling shoot traits of Saragolle Lucana and of <i>Trichoderma</i> inoculation effects on rhizosheath. This opens to new unreported interpretations of effects of <i>Trichoderma</i> inoculation on improving plant growth.
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