In the years 1997-1999 the occurrence of ryc diseases in the region of south-western Poland was investigated on rye varieties Warko, Dańkowskie Złote and hybrid rye Marder. Eyespot (Pseudocercosporella herpotrichoides var. acuformis) and brown rust (Puccinia recondita) occured most frequently in the experimental period. Fusarium stem base rot and leaf blight iFusarium spp.) and leaf scald iRhynchosporium secalis) were occasionally of considerable importance, but their occurrence was usually less frequent. Variety Marder showed high susceptibility to stem base and leaf diseases, especially to brown rust. When one treatment with fungicides was applied, grain yield increase of cv Marder reached the value of 20,03% in conditions of high infection by pathogens. It was concluded that in the years favourable for the development of diseases on ryc, chemical control with broad-spectrum fungicides might be advisable, especially for protecting susceptible varieties.

A novel herbicidal controlled release formulation composed of (2,4-dichlorophenoxy) acetic acid (2,4-D) chemically bonded to biodegradable (R,S)-3-hydroxybutyric acid oligomers was investigated. The synthesis of (R,S)-3-hydroxy butyric acid oligomers was carried out via the ring opening polymerization of β-butyrolactone initiated by 2,4-dichlorophenoxy acetic potassium salt in the presence of complexing agents. The formed oligomers were characterized by size exclusion chromatography, proton magnetic resonance and electrospray mass spectrometry in order to fi nd out their molar mass distribution and molecular structures. An assessment of biological effectiveness of the obtained herbicidal formulation was carried out in the greenhouse vs. Sinapis alba var. Nakielska. A promotion of the controlled release formulation with decreased water solubility and with low vapor pressure of the active ingredient, instead of traditional formulations of 2,4-dichlorophenoxy acetic acid may help to ensure a greater safety for workers and reduce the risk of dissemination of the active ingredient in the soil profi le.