| synthetic antimicrobial peptide design. | to guide the design of potential plant pathogen-resistance genes, synthetic variants of naturally occurring antimicrobial gene products were evaluated. five 20-amino acid (esf1, esf4, esf5, esf6, esf13), one 18-amino acid (esf12), and one 17-amino acid (esf17) amphipathic peptide sequences were designed, synthesized, and tested with in vitro bioassays. positive charges on the hydrophilic side of the peptide were shown to be essential for antifungal activity, yet the number of positive charges co ... | 1995 | 7579625 |
| increased septoria musiva resistance in transgenic hybrid poplar leaves expressing a wheat oxalate oxidase gene. | a cdna clone of a wheat germin-like oxalate oxidase (oxo) gene regulated by the constitutive camv 35s promoter was expressed in a hybrid poplar clone, populus x euramericana ('ogy'). previous studies showed that oxo is likely to play an important role in several aspects of plant development, stress response, and defense against pathogens. in order to study this wheat oxalate oxidase gene in woody plants, the expression of this gene and the functions of the encoded enzyme were examined in vitro a ... | 2001 | 11430425 |
| chronic ozone exposure increases the susceptibility of hybrid populus to disease caused by septoria musiva. | rooted cuttings of hybrid populus (dn34, populus deltoides x nigra) were grown outdoors in pots in open-top chambers at ithaca, ny (74.5 degrees w, 42.5 degrees n), during 1988 and 1989 (experiment 1) and during 1989 and 1990 (experiment 2). ambient air was passed through charcoal filters to produce a 0.5 times ambient ozone treatment, and ozone generated from oxygen was added to produce one and two times ambient ozone treatments. in experiment 1, treatments were applied for 8-12 h each day for ... | 1994 | 15091652 |
| specific and sensitive pcr-based detection of septoria musiva, s. populicola and s. populi, the causes of leaf spot and stem canker on poplars. | the development of a pcr assay for the detection of the poplar pathogenic fungi septoria musiva (teleomorph mycosphaerella populorum), s. populicola (m. populicola) and s. populi (m. populi) is described. three pairs of species-specific pcr primers were designed using interspecific polymorphisms in the internal transcribed spacer (its) of nuclear ribosomal rna gene (rdna) repeats. the specificity of the three primer pairs was successfully tested on a collection of 40 s. musiva, 39 s. populicola ... | 2005 | 16209307 |
| recessive resistance to septoria stem canker of hybrid poplar. | abstract stem canker, caused by septoria musiva, is the most serious disease limiting intensive hybrid poplar culture in eastern north america. populus deltoides (d) is itself resistant, but the susceptibility of western black cottonwood, p. trichocarpa (t) is apparently dominant in the f(1) generation. to test a hypothesis of recessive inheritance of canker resistance, a three-generation t x d pedigree was deployed in the field in iowa and minnesota. in both sites and in keeping with expectatio ... | 2001 | 18943444 |
| genetic structure of mycosphaerella populorum (anamorph septoria musiva) populations in north-central and northeastern north america. | abstract in order to characterize the genetic variation of the poplar pathogen mycosphaerella populorum (anamorph septoria musiva), we have studied seven north american populations using the polymerase chain reaction random amplified polymorphic dna (rapd) technique. the fungal populations were sampled in 2001 and 2002 by obtaining 352 isolates from cankers and leaf spots in hybrid poplar plantations and adjacent eastern cottonwood (populus deltoides). a total of 21 polymorphic rapd markers were ... | 2005 | 18943776 |
| effects of water stress on colonization of poplar stems and excised leaf disks by septoria musiva. | abstract septoria musiva causes leaf spot and canker diseases of trees in the genus populus, and is one of the most damaging fungal pathogens of hybrid poplar in eastern north america. the effect of host water stress on septoria canker development was studied in two separate greenhouse experiments. hybrid poplar clones nm6, nc11396, and ne308 were stressed by withholding water until predawn water potential fell below -1.0 mpa. stems were treated by removing a leaf and applying agar plugs that we ... | 1997 | 18945116 |