Related Experiment Video
Updated: Mar 30, 2026

A Contrast of Three Inoculation Techniques used to Determine the Race of Unknown Fusarium oxysporum f.sp. niveum Isolates
Published on: October 28, 2021
Virulence and Simple Sequence Repeat Marker Segregation in a Puccinia striiformis f. sp. tritici Population Produced
Yuan Tian1, Gangming Zhan1, Xianming Chen1
1First, second, fourth, fifth, sixth, seventh, and eighth authors: State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, P. R. China; and third author: USDA-ARS, Wheat Health, Genetics, and Quality Research Unit, and Department of Plant Pathology, Washington State University, Pullman 99164-6430.
Abstract:
Puccinia striiformis f. sp. tritici, the causal agent of wheat stripe rust, frequently produces new races overcoming resistance in wheat cultivars. A recently identified race, V26 with virulence to Yr26 and many other stripe rust resistance genes, has a high potential to cause epidemics in China. In this study, teliospores from a single-urediniospore isolate of V26 (Pinglan 17-7) produced on the wheat line 92R137 (Yr26) were used to produce a sexual population through selfing by infecting Berberis shensiana plants under controlled conditions. One hundred and eighteen progeny isolates and the parental isolate were phenotyped for virulence/avirulence on 24 Yr gene lines of wheat. These progeny isolates were all avirulent to Yr5, Yr8, Yr15, and YrTr1 and virulent to Yr1, Yr2, Yr7, Yr9, Yr10, Yr17, Yr24, Yr25, Yr26, YrA, YrExp2, and YrV23, indicating that the parental isolate is homozygous avirulent or homozygous virulent at these loci. The progeny population segregated for avirulence to Yr6, Yr43, and YrSP at one locus (3 avirulent:1 virulent ratio); for virulence to Yr27 and Yr28 at one locus (3 virulent:1 avirulent); and for Yr4, Yr32, and Yr44 at two loci (15 virulent:1 avirulent). Among the eight segregating avirulence/virulence loci, association was found between virulence to Yr4 and Yr32, as well as between virulence to Yr6 and Yr43 based on χ(2) tests. From 82 genotypically different progeny isolates, 24 pathotypes and 82 multilocus genotypes were identified. The results show that a highly diverse population can be produced from a single isolate by selfing on a barberry plant and sexually produced population can be used to genetically characterize virulence of the stripe rust pathogen.
More Related Videos
08:08Determination of Self- and Inter-incompatibility Relationships in Apricot Combining Hand-Pollination, Microscopy and Genetic Analyses
Published on: June 16, 2020
09:42Isolation and Selection of Entomopathogenic Fungi from Soil Samples and Evaluation of Fungal Virulence against Insect Pests
Published on: September 28, 2021
Related Concept Videos
Trihybrid Crosses
Some of Mendel’s crosses examined three pairs of contrasting characteristics. Such a cross is called a trihybrid cross. A trihybrid cross is a combination of three individual monohybrid crosses. For example, plant height (tall vs. short), seed shape (round vs. wrinkled), and seed color (yellow vs. green).
The F1 generation plants of a trihybrid cross are heterozygous for all three traits and produce eight gametes. Upon self-fertilization, these gametes have an equal...
Law of Segregation