Plant Hormone Signaling. Peter Hedden and Stephen G. Thomas (eds.). 2006. Blackwell Publishing Ltd., Oxford, UK. 377 pp. $211.99, hardcover. ISBN-13:978-14051-3887-1; ISBN-10:1-4051-3887-4. Progress during the past decade in our understanding of
Valtcho D. Zheljazkov, Tess Astatkie, Thomas Horgan, and S. Marie Rogers
plant hormones at three concentrations [methyl jasmonate (MJ) at 10, 100, and 1000 mg·L −1 ; gibberellic acid (GA3) at 10, 100, and 1000 mg·L −1 ; and salicylic acid (SA) at 10, 100, and 1000 mg·L −1 ]; Treatments 10 to 24 were the residual distillation
Ying Liu, Huawei Song, Juming Zhang, and Michael D. Richardson
). Recently, there has been considerable interest in the behavior of plant hormones in promoting root growth in plants ( Arite et al., 2012 ; Gonzalez-Perez et al., 2012 ; Wang et al., 2013 ). For example, SA acts as an endogenous signal and regulates
Yichun Wang, Violet Wert, Muraleedharan Nair, and Stanley Ries
A methanol: water extract of tomato (Lycopersion esculentum Mill.) apices increased the growth of the alga Chlamydomonas reinhardtii. The active substance from the dried shoot apices was purified by C18 flash column and high performance liquid chromatography. The purified extract enhanced the growth of tomato, corn (Zea mays L.), and rice (Oryza sativa L.) seedlings at concentrations less than 1.0 mg·liter-1 . With Chlamydomonas, the purified extract increased cell division 111% at 0.1 mg·liter-1 and chlorophyll content 23% at 10 mg·liter-1 in 18 hours. Nuclear magnetic resonance and mass spectroscopy indicated that the purified fraction was a mixture of compounds having sugar moieties. Analysis by thin layer chromatography showed that the fraction was ninhydrin positive and more polar than the known plant hormones studied.
Chia-Yun Ko, Tsai-Yun Lin, Chin-Wen Ho, and Jei-Fu Shaw
acid (1 mg·L −1 ), pyridoxine HCl (1 mg·L −1 ), thiamine HCl (10 mg·L −1 ), sucrose (20 g·L −1 ), phyto agar (8 g·L −1 ), and with no plant hormone. The pH of this modified medium (one-tenth MMS medium) was adjusted to 5.7 with 0.1 N KOH and HCl before
Xiaohua Yang, Susan K. Brown, and Peter J. Davies
caused by a blockage in the GA signaling pathway or by defects in other plant hormones that regulate plant form such as brassinosteroids or strigolactone ( Pereira-Lorenzo et al., 2009 ; Rameau, 2010 ). Literature Cited Alston, F.H. 1976 Dwarfing and
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.
Zhimin Yang, Jingjin Yu, Emily Merewitz, and Bingru Huang
drought or salinity tolerance include the accumulation of hormones and osmoregulants to govern plant water relations and protect against oxidative damage. Abscisic acid is a plant hormone that regulates plant response to water deficit by inducing stomatal
Shinsuke Agehara and Daniel I. Leskovar
primarily for height control and must be applied during early development, no later than 14 d after two to four true leaf stage. ABA is a plant hormone, which biosynthesis increases under water stress to induce adaptive stress responses ( Davies and Jones
Rongcai Yuan, Walter J. Kender, and Jacqueline K. Burns
The effects of removal of young fruit and application of auxin transport inhibitors on endogenous indole-3-acetic acid (IAA) and abscisic acid (ABA) concentrations were examined in relation to the response of mature `Valencia' orange [Citrus sinensis (L.) Osb.] fruit to abscission materials. ABA concentrations were increased in the fruit abscission zone and pulp but not in the pedicel, peel, or seed of mature fruit by removal of young fruit during the period of reduced response of mature fruit to abscission materials in early May. However, removal of young fruit slightly decreased IAA concentrations in leaves and the abscission zone and pedicel of mature fruit but had no effect on the IAA concentrations in the peel, pulp, or seed of mature fruit. Young fruit had higher IAA concentrations in the abscission zone and pedicel than mature fruit. Application of 2,3,5-triiodobenzoic acid (TIBA), an IAA transport inhibitor, reduced IAA concentrations in the abscission zone of mature fruit but did not influence the IAA concentrations in the pedicel and peel when applied directly to an absorbent collar tied around the pedicel 2 cm above the fruit abscission zone during the less responsive period in early May. ABA concentrations were increased drastically in the fruit abscission zone and pedicel but not in peel by TIBA application. Applications of ABA, or IAA transport inhibitors such as naringenin, quercetin, or TIBA comparably increased the response of mature fruit to the abscission material 5-chloro-3-methyl-4-nitro-1 H-pyrazole (CMN-pyrazole) in early May. These data suggest that young fruit reduce the response of mature `Valencia' oranges to abscission materials through increasing IAA concentrations and decreasing ABA concentrations in the abscission zone of mature `Valencia' orangees.