Synthesis of periclinal chimera in cassava

Abstract

ABSTRACT. We provide the first report on the synthesis of a very productive interspecific periclinal chimera of cassava, with large and edible roots. The epidermal tissue of the chimera was formed by the cultivated species Manihot esculenta (E), and the subepidermis and internal tissue were formed by the wild species, Manihot fortalezensis (F). We used cytogenetics and morphological analyses to determine the origins of all tissues. These results may offer potential for the development of new lines for crop improvement based on the use of chimera composed of different combinations of wild species and cultivars.

Research Article Periclinal chimera technique: new plant breeding approach

“…UnB 031) and characterized in this study. The four chimeras obtained so far at UnB are, therefore, chimera 1 induced in 2012 from M. fortalezensis x M. esculenta UnB 201 (Nassar and Bonfim, 2013), chimera 3 induced in 2012 (M. fortalezensis x M. esculenta UnB 032) (Bomfim and Nassar, 2014), and two others (chimera 2 and chimera 4) induced in August 2013 characterized in this investigation. Graft combination 1 had a chimera induction efficiency of 2.1%; one chimera was produced from 48 grafts that are lower than that the 5% obtained by Nassar and Bomfim (2013) (2 chimeras of 40 grafts) using the cassava cultivar UnB 201 as the rootstock and M. fortalezensis as the scion with hormones applied on the graft junction.…”

“…Meiotic chromosome counts of anthers allow L2 characterization because gametes are usually derived from the L2 layer (Satina et al, 1940;Goffreda et al, 1990), while mitotic chromosome counts on adventitious root tips allow the determination of the L3, since roots originate from the pericycle, which is derived from L3 layer (Medina et al, 2007;Nassar and Bonfim, 2013). Therefore, meiotic chromosome counting of L2-derived anthers and mitotic chromosome counting of L3-derived adventitious root tip cells were used for cytological characterization because of the different chromosome number of the donor plants of both chimera shoots as given above.…”

Plant Chimeras: the good, the bad, and the ‘Bizzaria’

“…The utility of interspecies mosaics extends to the field, where periclinal chimeras 207 between wild and domesticated genotypes serve as a means to physically combine 208 beneficial adaptations from wild species with the edible or otherwise useful 209 products of domestication. One particularly successful implementation of this 210 strategy is in cassava, where the combination of the wild species Manihot 211 fortalezensis with the cultivated species M. esculenta has been shown to boost edible 212 root size by a factor of seven---fold (Nassar and Bomfim, 2013). A similar approach to 213 plant improvement has been demonstrated for tomato where the epidermis of the 214 wild tomato species S. pennellii is sufficient to confer aphid resistance to a 215 domesticated inner core (Goffreda et al, 1990).…”

Research Article Cassava cultivars selected or developed from interspecific hybrids and periclinal chimeras

“…The epidermis is from fortalezensis cuttings. I was synthesized experimentally by grafting rootstock esculenta solution for seven days to induce adventitious chimeral shoots in the fusion region between scion and stock (Nassar and Bomfim, 2013). This variety presents very vigorous growth, when compared to parents under the same conditions.…”