Characterization of two wheat doubled haploid populations for resistance to common bunt and its association with agronomic traits

Abstract

Two segregating populations of doubled haploid (DH) wheat lines derived androgenetically from crosses 'Svilena' (susceptible) × A-38b-4-5-3-3 (highly resistant) and 'Svilena' × WWRN (moderately resistant to moderately susceptible) were characterized for resistance to common bunt. Disease incidence was evaluated after inoculation of seeds with a mixture of Tilletia foetida teliospores in two autumn sown field experiments. Two-gene model of inheritance of resistance in line A-38b-4-5-3-3 was suggested. The transgressive segregation in the latter population was indicative for a quantitative mode of inheritance. The DH lines were assessed for plant height, heading time and important yield components in a three-year field experiment without bunt infection. In both populations, transgressive segregation was observed for all agronomic characteristics. Although the disease incidence was positively correlated with most of the agronomic traits, genotypes combining bunt resistance with good yield potential were isolated from 'Svilena' × A-38b set of lines. These genotypes are valuable for breeding varieties designed for growing in low-input and organic farming systems. The two DH populations are suitable to be used for further studies on the genetic basis of bunt resistance.

Genetic architecture of common bunt resistance in winter wheat using genome-wide association study

“…They did not find any correlation between plant height and number of days to heading in one population consisting of 48 lines, while a low significant correlation was found between the resistance and days to heading (0.23*) and plant height (0.24**) in the other population with 115 genotypes. Based on our results and the results of [ 22 ] we can conclude that common bunt resistance seems to be an independent trait. The negative correlation between the percentage of infected heads and days to heading indicated that susceptible genotypes are usually heading earlier than resistant genotypes.…”

“…No significant correlation was found between common bunt resistance and plant height. The correlation between common bunt resistance and agronomic traits was previously tested in two different doubled haploid population [ 22 ]. They did not find any correlation between plant height and number of days to heading in one population consisting of 48 lines, while a low significant correlation was found between the resistance and days to heading (0.23*) and plant height (0.24**) in the other population with 115 genotypes.…”

Genetic Variation in Common Bunt Resistance in Synthetic Hexaploid Wheat

“…The worldwide set of the common bunt differential lines is very useful in identifying common bunt resistance genes in the germplasm of the tested genotypes. Using the differential lines for that purpose was performed previously [ 38 , 39 , 40 , 41 ]. These differential lines are available in the Department of Agricultural Research Service, National Small Grains Collection (NSGC) in Aberdeen, ID, and could be easily separated from each other, which makes them globally important [ 40 ].…”