Root development and structure in seedlings of Ginkgo biloba

Abstract

Seedling root axes of Ginkgo biloba are more complex than the literature suggests, and our findings contribute to our knowledge of root structure of this ancient gymnosperm.

The relationship between individual root anatomy and fine root system development in blueberry seedlings: dominance of diarch roots in initial root systems

“…The measured root traits except the cortex layer number, were significantly larger in diarch roots than in monarch roots (Table 1). Both the tapering pattern of PGs with progress of branching hierarchies and the characteristic differences between PGs are broadly similar with the root system of the cuttings and with several studies investigating primary root systems of tree species (Baba et al 2018, Bogar and Smith 1965, Bonacorsi and Seago 2016, Eissenstat and Achor 1999, Hayward and Long 1942. Therefore, it seems that individual roots with larger PGs produce roots with same or smaller PGs in branching architectures of many woody species, including blueberry seedlings.…”

“…In particular, the tapering pattern of PG distribution is known to occur in primary root systems of young seedlings in various tree species. For instance, in Ginkgo biloba L. (Ginkgoaceae) seedlings less than a year old, primary roots are diarch or triarch but secondary laterals are always diarch (Bonacorsi and Seago 2016. In our study, these ordering of roots in seedlings, primary or secondary, does not represent growing status but positional hierarchies related to radicles.…”

Phenotypic Plasticity in the Structure of Fine Adventitious Metasequoia glyptostroboides Roots Allows Adaptation to Aquatic and Terrestrial Environments

“…M. glyptostroboides roots from terrestrial and aquatic habitats have primary structures that include an endodermis, an exodermis, and lignified Φ thickenings in the cortex. In aquatic and terrestrial M. glyptostroboides , similar to very many other plants, roots develop a vascular cambium with secondary xylem and phloem, as well as a cork cambium, a phellogen with cork [13,27,42,43]. These cambia arise from the pericycle and the parenchyma between the primary phloem and xylem, as was observed in the fossil M. milleri [4].…”

“…The morphology of M. glyptostroboides and the structures of its fine adventitious roots, cuticle, and intertracheary pit membranes have been well studied [4,5,6,7,8,9]. The root structures in other gymnosperms, such as Thuja occidentalis , Libocedrus decurrens , Cunninghamia lanceolata , and Ginkgo biloba have been extensively investigated [10,11,12,13,14]. Lignified phi (Φ) thickenings have been recorded in the inner cortex adjacent to the endodermis in M. milleri [4] and are considered similar to the endodermis in the roots of C. lanceolata , M. glyptostroboides , and other gymnosperm species [9,14,15].…”

“…Lignified phi (Φ) thickenings have been recorded in the inner cortex adjacent to the endodermis in M. milleri [4] and are considered similar to the endodermis in the roots of C. lanceolata , M. glyptostroboides , and other gymnosperm species [9,14,15]. More broadly, lignified Φ thickenings have been reported in the root cortices of several species, including the gymnospermous Ginkgo biloba [13] and C. lanceolata [14], and the angiospermous Pyrus malus [16], Brassica napus , B. oleracea [17,18], Myrica rubra [19], and Cardamine hupingshanensis [20].…”