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 ...
The study was conducted in 2008-2009 at the Agricultural Experimental Station in Lipnik near Stargard, on sandy soil. The aim of this study was to determine the effect of sub-crown irrigation on the yield leaves photosynthesis and transpiration capacity, as well as CO2 concentration in the stomatal cells, and leaf greenness index of early 'Geneva Early' cv. and late 'Rubinola' cv. apple cultivars.Irrigation was applied in the form of the sub-crown system, in which water is distributed through a mini-sprayers of Hadar type when water potential of soil fell below -0.01 MPa. The experiment was established in a randomized sub-block pattern (split-plot) in 10 replicates. The study was conducted using the four-year-old trees. The trees were planted at 4 × 2 m spacing; one hectare was planted with 1250 trees. Turf was maintained between the trees, while herbicide fallow was applied in rows. Plant material for laboratory tests was collected each year in three dates: fruit setting (date 1), harvest (date 2) and one month after the harvest (date 3). Studies have shown that leaves of the irrigated apple trees were lower content of assimilation pigments in leaves than non-irrigated ones. Leaves of late ‘Rubinola' cv. showed higher ...
