An experiment was conducted at the United Arab Emirates Univ., in Al-Ain, to study the effect of saline water on the growth characteristics of date palm (Phoenix dactylifera L.) seedings cultivar Lulu-salt alone or a combination of NaCl and indole acetic acid (IAA) or IAA alone were tested with different levels. Then the plant growth characteristics were measured. Hormone did not antagonize the salt effect on shoot length of date palm seedlings. Application of 24 mg·L–1 salt alone or in combination with hormone and 12 mg·L–1 in combination with 0.2 mg·L–1 IAA significantly increased the root: shoot ratio over the control. Irrigation date palm seedlings with saline water alone or in combination with IAA for 80 days resulted in a significant increase in dry matter (percentage) of leaves with salt symptoms, whereas the number of leaves per seedling were reduced over the control. The results also showed that the irrigation of seedlings with 0.15 mg·L–1 IAA in combination with 24 or 12 mg·L–1 salt alleviated adverse effect of salt by increasing or reducing significantly root length or leaves with salt symptoms percentage over using 24 or 12 mg·L–1 salt alone.
Y.D. Park, A.A. Boe, and M.K. Ehlenfeldt
Leaf disks of potato cv. Kennebec and ND 860-2 (North Dakota potato breeding clone) were cultured on Murashige Skoog (MS) medium supplemented with 6 levels of indole acetic acid (IAA) and 7 levels of zeatin riboside (ZR). Shoots were induced at various combinations of hormone levels. The medium containing 3.5 mg/l IAA and 4.0 mg/l ZR produced the most shoots. Rooted plantlets were grown in the greenhouse. The growth of regenerated plants obtained from the MS medium supplemented with 7.0 mg/l IAA and 3.0 mg/l ZR was significantly greater than those grown from nodal explants. In ND 8602, a leaf chimera with chlorophyll deficient (light yellow) sectors was found in plants regenerated from leaf disks (grown on MS medium supplemented with 3.5 mg/l IAA and 3.0 mg/l ZR) but not in plants grown from nodal explants. Phenotypic variability was also observed for tuber number, size and weight.
Shuming Ju, Lingzhen Ji, and Delan Xu
that the plants had an additional growing season in autumn. In addition, at that time, IAA content of the upper terminal bud was greater than that of the middle and lower terminal buds. Fig. 1. Change in indole acetic acid (IAA) content in
Ying Gao, Hao Liu, and Dong Pei
species, in which male and female individuals produce unisexual flowers and are characterized by sexual dimorphism ( Cristiana Moliterni et al., 2004 ). In this present study, an anti-indole acetic acid (IAA) monoclonal antibody was used to detect and
Jing Wei Dai and Robert E. Paull
D.M. Glenn and R. Scorza
In reciprocal grafts of tall (`Elberta' and `Loring') and dwarf (`Empress' and `Juseito') peach (Prunus persica Batsch.) phenotypes, we measured dry-matter partitioning, resistance to root system water flow, and phytohormone content of xylem exudate. Scion characteristics determined the phenotype and growth characteristics of the tree irrespective of the rootstock. Tall phenotypes had higher dry weight and lower root resistance to water flow than dwarf phenotypes. Cytokinin-like activity and auxin levels in xylem sap were higher in dwarf than in tall phenotypes; whereas gibberellin-like activity was unaffected by either rootstock or scion. The scion of peach influenced phytohormone levels and resistance to water flow in the root system in addition to root and shoot growth.
Alberto C.Q. Pinto, Suzanne M. Dethier Rogers, and David H. Byrne
The influence of medium formulation, methods of ovule support, and ovule perforation on in vitro growth of immature peach [Prunus persica (L.) Batsch] embryos (4.0 to 8.7 mm long) was investigated. Maximum embryo dry weights were attained with vermiculite support, ovule perforation, and 10% sucrose in the medium. At high sucrose levels, all three tested media (Monnier, modified Murashige and Skoog, or modified Stewart and Hsu medium) performed similarly. Adding IAA and kinetin to culture media did not enhance embryo growth. Using the vermiculite support system, small embryos of early maturing peach cultivars, obtained at fruit maturity, were cultured successfully and used as maternal parents in breeding programs. Chemical name used: indole acetic acid (IAA).
Vincent M. Russo
Exogenously applied plant growth regulators may affect development of onion, but little is know about how concentration or timing of application can affect bulb grade and quality. Two concentrations of the growth regulators abscisic acid, gibberellic acid, indole-acetic acid, jasmonic acid, kinetin, and maleic acid hydrazide, and water controls, were applied at the 7- and 20-leaf stages to the middle of the leaf whorl in greenhouse grown onion plants. Leaf and bulb weights were lighter, and bulb diameters were smaller, from plants treated with growth regulators applied at the 7-leaf stage than those from plants treated at the 20-leaf stage. Bulbs produced on plants treated with water were the same size, or larger, than those produced on plants treated with individual growth regulators.
I. Baktir, S. Ulger, L. Kaynak, and David G. Himelrick
Changes in hormone concentrations in leaf, node, shoot tip, and fruit samples of three Turkish olive (Olea europaea L.) cultivars (`Gemlik', `Memecik', and `Tavsan Yuregi') were monitored at monthly intervals over two successive years of the alternate-bearing cycle. Concentrations of abscisic acid (ABA), indole acetic acid (IAA), gibberellic acid-like substances (GA), and kinetin-like cytokinin were determined and their relationship to flower bud formation were examined during “on” and “off” years. Results showed significant differences in IAA, ABA, GA3-like, and kinetin-like cytokinins between “on” and “off” cropping years in various tissues of olive trees. Relative balances between GA3-like and ABA concentrations of tissues appears to exhibit evidence of being a key regulator of floral development and alternate bearing.
Azza A. Tawfik, Susan L. Cuppett, and Paul E. Read
Shoot tips (7 to 10 mm long) of rosemary plant (Rosmarinus officinalis L. 'Lockwood de forest') were cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ) (0, 0.5, 1.0, 1.5, and 2 mg/l) alone or with 3-indole acetic acid (IAA) at 0.5 mg/l. The effect of TDZ and IAA on the proliferation of rosemary shoot tips has been reported in a previous meeting. Here, we report on the effect of TDZ and IAA on the monoterpene constituents identified in the oil of rosemary plants propagated in vitro. The proliferated explants were soaked in hexane as a solvent, then the extractions were used for monoterpene analysis using GC/MS. A significant interaction of TDZ by IAA was found on most of the oil components identified. The highest levels of 1,8-cineole and borneol were obtained at 0.5 mg TDZ/l alone, while the highest level of camphor was obtained at 0.5 mg TDZ/l plus 0.5 mg IAA/l. The highest level of bornyl acetate was at 2 mg TDZ/l.