Architectural analysis of root system of sexually vs. vegetatively propagated yam (Dioscorea rotundata Poir.), a tuber monocot

Abstract

International audienceArchitectural descriptors were used to understand root system structure and development in white yam (Dioscorea rotundata Poir., Dioscoreaceae), a tuber monocot. Observations were made on seedlings and plant derived from tuber fragments, cultivated in greenhouses over a developmental cycle. This study demonstrated that both seedlings and plants derived from tubers have two distinct root systems that are highly organized. The first (seminal or tubercular) has been called the temporary root system which is small and short lived. The architectural unit here is made up of two root axis categories. The second (adventitious in both cases) has been called the definitive root system. It is larger and has a far longer lifespan than temporary root systems. The architectural unit here is made up of three root axis categories. Adventitious root systems are formed by structural repetitions of their own architectural unit. The temporary and definitive root systems possess the same structural and functional properties and become established and succeed one another in time following an identical developmental sequence. Neo tuber development is coupled with the root system development. Our results highlight to what extent it is important to study simultaneously the different parts of a root system in order to understand its development. This study confirms how architectural tools can be used to understand root system structure and development and prove accurate informations on root system development for use in agricultural management

Growth and Distribution of Roots of Dioscorea Alata L. Do Not Respond to Mineral Fertiliser Application

“…The root system of D. alata observed in this study consisted of three types of roots which replaced each other over the growing season. In addition to the seminal and the adventitious roots observed by Charles-Dominique et al [8] for a cultivar of D. rotundata, we also observed tubercular roots on the newly developed tuber. These tubercular roots replaced the adventitious roots 4-5 months after planting when the adventitious roots started dying off.…”

“…Testing the relation between the root morphology of yam and its response to mineral fertiliser application is challenging because of our limited knowledge on the yam root system. The yam's root system has been described [6][7][8] but not yet linked to the fertiliser response of the crop. Furthermore, root distribution patterns may also be affected by the study technique used [9,10].…”

Propagation Techniques and Grafting Modify the Morphological Traits of Roots and Biomass Allocation in Avocado Trees

“…The propagation technique affected the root growth angle of the main roots (third order roots), root length density, and the number of first and second order roots present. Our results are consistent with previous reports of this effect in other species (Asaah et al, 2012;Charles-Dominique et al, 2009;Piccotino et al, 1992;Severino et al, 2011). In avocado clonal rootstocks, the main roots of etiolated stems were positioned at right angles to the main axis.…”

Retrospective analysis of tree architecture in silver fir (Abies alba Mill.): ontogenetic trends and responses to environmental variability

“…Future work on retrospective analysis may focus on root growth (Jourdan and Rey 1997;Charles-Dominique et al 2009) and on tropical species (Zalamea et al 2008;Rutishauser et al 2011).…”