The aim of the study was to determine the impact of microirrigation of Barycz, Mors and Triada potato cultivars on the infection of tubers by the most dangerous pathogens. The experiment was carried out on light soil as a two-factor split-plot design with four replications. The factors were cultivars and the following variants of irrigation: WO - without irrigation, W1 - drip irrigation, W2 - micro-sprinkler irrigation. The health status of tubers was evaluated after harvest in each year of the study. The percentage of an area of the tubers with symptoms of common scab and black scurf was determined following nine-degree (0-8) scale were: 0 = lack of disease symptoms, healthy tubers and 8 = above 50% of a tuber surface with disease symptoms. The percentage of tubers with symptoms of in-festation was estimated for other detected diseases. Symptoms of common scab and black scurf were observed on the tubers in all years of the study. Studied cultivars differed in susceptibility to Streptomyces sp. and Rhizoctonia solani. The most resistant cultivar to the first pathogen was Triada and to the second pathogen was Barycz. Symptoms of other diseases were noted sporadically and did not exceed 1% of infected tubers. ...
Asparagus infection with numerous pathogens very often decreases yield of spears. Efficient protection of asparagus plantation can be very difficult and sometimes even unavailable due to lack of effective plant protection agents to control of some pathogens. The choose of cultivar and field before the establishment of plantation are crucial in such cases. Irrigation has also a very considerable impact on asparagus yielding. It can influenced the diseases development too. The aim of the research was to evaluate the susceptibility of microirrigated, three German asparagus cultivars to the plants infection by pathogens.The field experiment was settled in 1998 at KruszynKrajenski near Bydgoszcz on a sandy soil. The first factor was microirrigation used in variants: W1 - non-irrigated plots (control), W2 - drip-irrigated plots, W3 - microsprinkler-irrigated plots. Irrigation doses were adequate for amount and distribution of rain-precipitation and were found out by tensiometers, too. They amounted to 195 and 113 mm for micro-sprinkler and drip irrigation, respectively. The second factor were three German cultivars of asparagus: ‘Ap', ‘Gr' and ‘SchwetzigerMeisterschuss', grown for blanched spears. Plant healthiness observations were carried out in the first 4 harvest years (2000-2004). Occurrence of root and stem rot (Fusariumoxysporumf.sp. asparagi, F. culmorum), asparagus rust ...
