Screening of wheat cross material and breeding lines in respect of susceptibility for bunt diseases an freshly infested and ecologically farmed fields
Robert Bauer, Benno Voit, Berta Killermann
Field trial 2014/2015 (second growing year)
As described in the last update, 36 wheat varieties and breeding lines were sown on October 29th 2014 at the test site of Wolfersdorf, in two replications with 10 m row length and 25 cm row spacing by a hand-drawn sowing machine. For sowing the harvested material of 2014 was used. In contrast to 2014 cultivars with the resistance genes Bt8 and Bt9 were added, whereas some breeding lines were excluded. Soil samples for determination of the spore potential in soil were taken on the sowing date. With the analyzed amount of 1,200 spores per 10 g soil on average an infestation could be expected. Stand development after winter was good. Conditions for a dwarf infestation were favorable since the soil was not frozen most of the time and from the end of December to mid of January the field trials have been snow covered.
Harvest was carried out at the end of July/beginning of August. All plants per row were cut by hand, sacked and stored. Infested ears were counted and taken out. Also the total number of ears per row was determined. The preliminary results of the percentage of ear infection are shown in Fig. 1. Average of infection was slightly less than in 2015, due to the lower bunt spore potential in soil. Susceptibility of the tested varieties was very similar to the results of the first project year. The number of spores per kernel of the varieties will be analyzed by threshing the remaining healthy ears and by infecting them with the crushed infected ears. Final results are expected for the end of October 2015.