Adventitious root development

Incomplete cessation cell division, root tip swelling and adventitious root development. Root uptake reduced, roots softened and decayed. 

The Duboisia myoporoides - D. leichhardtii hybrid (M-II-8-6), which was used for explants, is cultivated at the Research Center for Medicinal Plant Resources, Tsukuba, Japan. Leaves were dipped in 75% ethanol for 10 seconds, rinsed in sterilized water, surface-sterilized for 10 minutes in 2% sodium hypochlorite containing Tween 20 (1 drop per 40 ml) and then washed three times with sterilized water. Leaf segments (ca. 5x5 mm) were incubated on MS solid medium containing 1 mg/1 lAA and 3% sucrose in the dark at 25 "C. Within 3 weeks, adventitious roots developed. 

Brassinosteroids have also been observed to inhibit adventitious root development in mung bean hypocotyls [72]. Subsequent work reviewed by Roddick et al. [73] indicated that this inhibition might not be a primary action of BRs and may... 

Though the number of shoots developing adventitious roots was not significantly different between treated samples and control, the average length of adventitious roots declined significantly at 500 ppmw. At this concentration, roots appeared somewhat brownish while the tips were slightly swollen. 

Adventitious roots are such as occur in abnormal places on the plant. Examples Roots developing on Bryophyllum and Begonia leaves when placed in moist sand. 

In the meantime, the formation of the main alkaloids in C. ipecacuanha under a variety of conditions has been extensively investigated emetine (1) in callus cultures (49) and under the effects of L-tyrosine supplementation (5t)) emetine (1) and cephaeline (2) in Panamanian ipecac (57), in Nicaraguan ipecac (52), in regenerates obtained by clonal propagation (53,54), in tissue cultures (55) and under the effects of exogenous feeding of shikimic acid and L-phenylalanine (55), in cell suspension and excised root cultures (57), in adventitious root cultures (58), and in callus cultures (56,59) and the effects of age and electrokinetic potential (60) ipecoside (7) in the roots (61) and the effect oi Azotobacter, leaf mold, and farmyard manure on alkaloid content (62). In addition, micropropagation systems for C. ipecacuanha have been developed (63-65). 

Abscisic acid (ABA) levels in rice plants, 308,31Or levels in squash hypocotyls, 315/.316 Active component of brassins identification, 9,lQf pilot plant extraction, 6,7/,8 solvent partition and column chromatography, 8 Adventitious root(s) development, 233,234r,235 formation, 247 Agriculture, application of 24-epibrassinolide, 280-290 22-Aldehydes, synthesis of brassinosteroids, 47-50f a hormone function, description for brassins, 4... 

While the application of relatively high concentrations of lAA retard root elongation, there may be a considerable increase in the development of branch roots and root hairs (27). As a result, the practice of dipping cuttings in auxin has become commercially important in promoting the proliferation of adventitious roots. Usually, synthetic auxins, such as indole-3-butyric acid (IBA) and naphthaleneacetic acid(NAA) which are not subject to lAA oxidase, are used. 

In contrasted to the embryogenesis, organogenesis occurs via apparent shoot meristem or leaf primordial (Fig.2h-i). Histological analysis shows that non-embryogenic cells are large, and vacuolated parenchymal cells contain few plastids (Zhang et al., 2010). Callus will differentiate into adventitious shoots, and develop with subsequent formation of adventitious roots. 

Several potential sources of artifacts can also be ruled out through the use of soybean explants. CK has little delaying effect on pod development in these explants indicating that the CK does not retard leaf senescence indirectly through action on the pods. Because (a) the explants placed on mineral medium tend to produce adventitious roots (while those cultured on water tend not to) and (b) roots... 

It is a general observation that seedlings raised under the influence, for instance, of tetcyclacis or triazoles exhibit a shoot-root-ratio which has shifted in favor of the root. In many cases, root growth is stimulated and longer and thicker main roots can be observed, while the formation of adventitious roots and root hairs is initially inhibited [38]. The formation of an improved root system may be one of the reasons why most of these plants show a better performance at later stages of development. 

A primary root system is developed, but is replaced by an adventitious root system. 

This is found on all grasses and cereals, and it is the main root system of most monocotyledons. The primaiy root is soon replaced by adventitious roots, which arise from the base of the stem (Fig. 1.12). These roots can, in fact, develop from any part of the stem, and they are found on some dicotyledons as well (but not as the main root system), e.g. underground stems of the potato. 

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