| soybean brown stem rot, phytophthora sojae, and heterodera glycines affected by soil texture and tillage relations. | abstract investigations were conducted to determine whether the effects of tillage practices on the prevalence of brown stem rot of soybean (caused by phialophora gregata), heterodera glycines, and phytophthora sojae were confounded by soil texture in samples collected in the fall of 1995 and 1996. soil and soybean stem samples, along with tillage information, were collected from 1,462 randomly selected fields in illinois, iowa, minnesota, missouri, and ohio in collaboration with the national ag ... | 1999 | 18944726 |
| regional assessment of soybean brown stem rot, phytophthora sojae, and heterodera glycines using area-frame sampling: prevalence and effects of tillage. | abstract the prevalence of brown stem rot (caused by phialophora gregata), heterodera glycines, and phytophthora sojae in the north central united states was investigated during the fall of 1995 and 1996. soybean fields were randomly selected using an area-frame sampling design in collaboration with the national agricultural statistics service. soil and soybean stem samples, along with tillage information, were collected from 1,462 fields in illinois, iowa, minnesota, missouri, and ohio. an addi ... | 1999 | 18944760 |
| real-time pcr assays for the quantification of phialophora gregata f. sp. sojae igs genotypes a and b. | populations of phialophora gregata f. sp. sojae, the causal agent of brown stem rot (bsr) of soybean, consist of two genotypes, designated a and b. these genotypes are differentiated by an insertion or deletion in the intergenic spacer region (igs) of ribosomal dna. the two genotypes differ in the type and severity of symptoms they cause and have displayed preferential host colonization. methods to quantify populations of p. gregata f. sp. sojae and to distinguish between the two genotypes are e ... | 2009 | 19671002 |
| response of soybean pathogens to glyceollin. | plants recognize invading pathogens and respond biochemically to prevent invasion or inhibit colonization in plant cells. enhancing this response in crop plants could improve sustainable methods to manage plant diseases. to enhance disease resistance in soybean, the soybean phytoalexin glyceollin was assessed in soybean hairy roots of two soybean genotypes, spencer and pi 567374, transformed with either soybean isoflavone synthase (ifs2) or chalcone synthase (chs6) genes that were inoculated wit ... | 2010 | 20701487 |
| a molecular marker identifying subspecific populations of the soybean brown stem rot pathogen, phialophora gregata. | abstract a molecular marker was developed to separate and identify subspecific populations of phialophora gregata, the causal agent of soybean brown stem rot. a variable dna region in the intergenic spacer of the nuclear rdna was identified. two specific primers flanking the variable region were developed for easy identification of the genotypes using polymerase chain reaction (pcr). these two specific primers amplified three dna products. the three pcr products were used to separate isolates of ... | 2000 | 18944509 |
| characterization and distribution of two races of phialophora gregata in the north-central united states. | abstract genetic variation and variation in aggressiveness in phialophora gregata f. sp. sojae, the cause of brown stem rot of soybean, was characterized in a sample of 209 isolates from the north-central region. the isolates were collected from soybean plants without regard to symptoms from randomly selected soybean fields. seven genotypes (a1, a2, a4, a5, a6, m1, and m2) were distinguished based on dna fingerprinting with microsatellite probes (cat)(5) and (cac)(5), with only minor genetic var ... | 2003 | 18943172 |
| isolation of gregatin a from phialophora gregata by preparative high-pressure liquid chromatography. | a method was developed for the production and purification of gregatin a from phialophora gregata nrrl 13198 cultured on rice at 20 degrees c for 28 days. liquid extraction followed by high-pressure liquid chromatography afforded 247.0 mg of crystalline gregatin a per kg of rice. | 1985 | 16346936 |
| investigating the genetic model for brown stem rot resistance in soybean. | genetic analyses have indicated that brown stem rot (bsr) resistance in soybean is conferred by dominant alleles at three independent loci, the actions of which may be modified by linked or independent loci. a study was conducted to characterize the inheritance of bsr resistance in pi 567609, a soybean plant introduction from china. segregating progeny from crosses of pi 567609 with bsr-susceptible and -resistant genotypes were evaluated for response to bsr-causal fungus, phialophora gregata. ge ... | 2000 | 10912679 |
| glyceollin, a soybean phytoalexin with medicinal properties. | this review covers the biosynthesis of glyceollin and its biological activities including antiproliferative/antitumor action (toward b16 melanoma cells, lncap prostate cancer cells, and bg-1 ovarian cancer cells), anti-estrogenic action (through estrogen receptors a- and ß-), antibacterial action (toward erwinia carotovora, escherichia coli, bradyrhizobium japonicum, sinorhizobium fredii ), antinematode activity, and antifungal activity (toward fusarium solani, phakospora pachyrhizi, diaporthe p ... | 2011 | 21336922 |