Messenger and hybridizing

Has anyone used Messenger on your breeding roses? Did it affect the seed set and/or germination? I

Joan, our rose society has used messenger for a couple of years with positive results and never any problems. I have used it on my seedlings. Reports from our RS show more, larger and healthier growth. Robyn

Title: Downstream divergence of the ethylene signaling pathway for harpin -stimulated Arabidopsis growth and insect defense.

Authors: Dong, Hong-Ping; Peng, Jianling; Bao, Zhilong; Meng, Xiangdong; Bonasera, Jean M.; Chen, Guangyong; Beer, Steven V.; Dong, Hansong.

Authors affiliation: Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Peop. Rep. China.

Published in: Plant Physiology (2004), 136(3), pages 3628-3638.

Abstract: “Ethylene (ET) signal transduction may regulate plant growth and defense, depending on which components are recruited into the pathway in response to different stimuli. We report here that the ET pathway controls both insect resistance (IR) and plant growth enhancement (PGE) in Arabidopsis (Arabidopsis thaliana) plants responding to harpin, a protein produced by a plant pathogenic bacterium. PGE may result from spraying plant tops with harpin or by soaking seeds in harpin soln.; the latter esp. enhances root growth. Plants treated similarly develop resistance to the green peach aphid (Myzus persicae). The salicylic acid pathway, although activated by harpin, does not lead to PGE and IR. By contrast, PGE and IR are induced in both wild-type plants and genotypes that have defects in salicylic acid signaling. In response to harpin, levels of jasmonic acid (JA) decrease, and the COI1 gene, which is indispensable for JA signal transduction, is not expressed in wild-type plants. However, PGE and IR are stimulated in the JA-resistant mutant jar1-1. In the wild type, PGE and IR develop coincidently with increases in ET levels and the expression of several genes essential for ET signaling. The ET receptor gene ETR1 is required because both phenotypes are arrested in the etr1-1 mutant. Consistently, inhibition of ET perception nullifies the induction of both PGE and IR. The signal transducer EIN2 is required for IR, and EIN5 is required for PGE because IR and PGE are impaired correspondingly in the ein2-1 and ein5-1 mutants. Therefore, harpin activates ET signaling while conscribing EIN2 and EIN5 to confer IR and PGE, resp.”