were five replicates (one plant per pot = one replicate) in each of the LR characterization experiments and in each of the substrate moisture experimental treatments. As a result of the variability of the number of adventitious roots per plant, there
Arthur Villordon, Don LaBonte, Julio Solis, and Nurit Firon
J. Roger Harris and Susan D. Day
within the container root ball of these or other trees is unknown. Gilman and Harchick (2008) reported that deep planting of cutting-grown live oak ( Quercus virginiana ‘SDLN’ Cathedral Oak®) resulted in additional adventitious roots and circling roots
Thomas E. Marler
( Marler and Cruz, 2017 ) because excavation of intact roots for traditional transplant operations was cost-prohibitive. This unprecedented attempt to initiate adventitious roots on large cycad stems resulted in 41% success in adventitious root formation
Edward F. Gilman and Michael E. Kane
Post-planting root development of red maple (Acer rubrum L.) on a well-drained site was compared with that on a site with a high water table. Container-grown red maple planted in 1985 were excavated in 1988 and cross-sectional root area (CSRA) calculated for roots >1 cm diameter, 5 cm beyond the edge of the original container rootball. Adventitious roots were generated in the field after planting, not in the container. Total adventitious CSRA was three times greater than CSRA of roots generated from the original container-produced root system. The number of adventitious roots (7.6) generated from the trunk and primary root after planting was greater than the number of roots originating from the existing root system (4.2). Adventitious root origin on both sites was within 5 cm of the soil surface, above the often circling, kinked, or twisted roots found within the container root ball. Four of the five largest roots were of adventitious origin. Root number, size, and growth rate were not modified by differences in cultural and environmental conditions between sites.
Ahmed A. Obeidy and M.A.L. Smith
The regenerative capacity of mature pecan [Carya illinoinensis (Wangenh.) K. Koch] embryonic tissues was demonstrated after pretreating mature nuts to eliminate associated endogenous contaminants. Cultured cotyledon segments were induced to form adventitious roots in a medium with 50 μm NAA. A regeneration medium with 20 μm BA and 5 μm IBA stimulated prolific axillary shoot production from the embryonic axis without causing cotyledon abscission. Cotyledon retention was essential for shoot initiation and long-term development. Eighty-five percent of the shoots emerging from embryonic axes formed at the cotyledonary nodes. Thirty percent of the microshoots rooted on an auxin-free medium after preculture in a medium with 20 μm IBA. TDZ (25 μm) stimulated callus production from the cotyledonary nodes and radicles. Adventitious buds emerged on the callus surface and internally in callus. Chemical names used: a -naphthaleneacetic acid (NAA); 6-benzylaminopurine (BA); indole-3-butyric acid (IBA); N-phenyl-N'-1,2,3-thidiazol-5-ylurea (TDZ).
Zhaohui Li, Yan Ma, Wanyuan Yin, Dekui Zang, and Xianfeng Guo
visible external morphological change comprised basal swelling and callus formation around the cut surface of cuttings on day 5 ( Fig. 2B ), callus mass enlargement and enhancement on day 10 ( Fig. 2C ), emergence of adventitious roots through the callus
Arthur Villordon, Christopher Clark, Tara Smith, Don Ferrin, and Don LaBonte
). Recently, we have documented that up to 85% of adventitious roots extant at 5 to 7 d after transplanting (DAT) have the potential to become storage roots ( Villordon et al., 2009b ). The uniform and consistent initiation of adventitious roots has been shown
Ute Albrecht, Mireia Bordas, Beth Lamb, Bo Meyering, and Kim D. Bowman
the taproot may, therefore, respond differently to different supplies of nutrients and water than trees with fibrous roots arising from adventitious roots of vegetative origin. Recent studies on HLB-affected citrus have shown that loss of fibrous roots
Benyamin Lakitan, David W. Wolfe, and Richard W. Zobel
Greenhouse experiments were conducted in 1987 and 1988 to evaluate the effect of timing of a 4-day flooding stress on growth and yield of snap bean (Phaseolus vulgaris L. cv. Bush Blue Lake 274, BBL). Plant survival was reduced when flooding was imposed at postflowering growth stages, but most plants survived when flooded before flowering or when reproductive development was prevented by deflowering. Early yields of surviving plants were very low in all flooded treatments, regardless of timing, in both years. Total yield response to timing of flooding was linear in 1987, with lowest yields when flooding was imposed at later growth stages. The trend was not linear in 1988, but in both years the latest flooding treatment (36 days after planting) had few surviving plants and no measurable pod yield. Additional greenhouse experiments revealed that leaf conductance of BBL and another bean cultivar, Luna (LN), declined within the first day of flooding. This decline was concomitant with one in leaf water potential and photosynthesis (Pn) in BBL, but decline of these responses occurred 1 to 2 days later for LN. After 4 days of flooding, Pn fell to near 0 for BBL, and to 15% of the prestress value for LN. Pn of both cultivars had recovered to 18.5 μmol·m-2·s-1 10 days after termination of flooding. LN had a larger adventitious root biomass, higher percentage of adventitious roots, and a consistently lower leaf: root ratio than BBL during recovery.
Abigail R. Debner, Harlene Hatterman-Valenti, and Fumiomi Takeda
weekly hand misting. Both cultivars produced adventitious roots within 10 to 14 d, with most of the roots forming at the base of the bud. Soon after root formation, a flower shoot emerged from the axillary bud; ≈2 months later, the flowers on the