The 1987-1992 microplots experiment was conduced in agricultural field conditions under routine crop, and herbicide rotation. Over the experimental time only the endoparasitic species, Pratylenchus neglectus revealed significant changes in the population dynamics. In a sugar beet the nematode population decreasad in microplots treated with chloridazon (3.25 kg/ha) or cycloate (4.44 kg/ha) but increased in the control. In a winter rape the population ofP neg/ecrus increased in microplots treated with benazolin (0.45 kg/ha) but it decreased in the control. The observed trends in the dynamics of the nematode population persisted for one year only, and they were changed with the rotation of crop and herbicides. No differences betwen herbicides treated, and control microplots were observed with linuron + bentazone (10 kg/ha + 1.5 kg/ha, respectively) was applied to pea culture, metabenzthiazuron (2.8 kg/ha) was applied to a winter wheat, and MCPA as sodium salt + dicamba as sodium salt (0.725 kg/ha + 0.08 kg/ha, respectively) was applied to a spring wheat. The examined crops and herbicides did not markedly affect the population dynamics of ectoparasitic Tylenchorhynchus dubius, Helicotylenchus digonicus and Mesocrico nema curvatum.

In greenhouse experiments the susceptibility of meadow fescue, perennial ryegrass and Italian ryegrass to Fusarium avenaceum, F. cu/mor um and F. grami num infection was studied. Various responses to Fusarium spp. infection were observed among the tested grass species and their cult i vars. Meadow fescue was the most susceptible to all the Fusarium isolates used. F. avenaceum isolates also strongly reduced perennial ryegrass emergence. In the experiments with Italian ryegrass the number of seedlings having survived the artificial infection of seeds with Fusarium spp. was significantly larger for Atos, Gran, Mitos and Polus cultivars than for Kroto, Lotos and Tur. All of the studied grasses were more susceptible to the strongly pathogenic F. avenaceum isolates than to F. culmorum and F. graminum isolates, having moderate pathogenicity.

In the years 1999-2000 the occurrence oferiophyoids on grasses was studied in the Wielkopolska region. 9 eriophyoid species were recognized on 29 grass species. Eriophyoids were present in 38% examined plant samples. The most often infested were Agropyron repens and Lolium perenne and the least Arrhenatherum elatius. Abacarus hystrix and Aculodes mckenziei were the dominating eriophyoid species. The intensity of occurrence varied and was related to the eriophyoid species and the host plant. Feeding of some eriophyoids species caused either matting or browning or twisting of the leaf blades.

Phenoxy acids significantly increased the number of Sitobion avenae F. and Rhopalosiphum padi L.on wheat treated with Aminopielik D and Illoxan 36 EC. This herbicidal effect could be caused directly by derivatives ofphenoxy acid or indirectly by altered metabolism of wheat plant.

Siddiqi M.R. 2000. Tylcnchida: Parasites of Plants and Insects, 2°• Edition. CABI Publishing, Wallingford. 833 + XVII pp., ISBN 0851992021.

B. Weischer, D.J.F. Brown. 2000. An introduction to Nematodcs: General Nematology. Pensof Publishers, Sofia, 202 pp., ISBN 954-642-087-5

Influence of grapefruit extract (GE) on mycelial growth, spore germination, population density of Fusarium oxysporum f. sp. cyclaminis and F. oxysporum f. sp. dianthi and its effectiveness in the control of Fusarium wilt of carnation and Fusarium corm rot of gladiolus (F. oxysporum f. sp. gladioli) was studied. Amendment of PDA with 40 μg ofGE/cm3 inhibited mycelial growth about 50%. Drenching of carnation with 165 μg of GE/cm 3, immediately after planting, resulted in drastical decrease of colony forming units number of the pathogen and increased healthiness plant stand about 50%. Applied as gladiolus corm soak, GE at cone. 660 ug/crrr' decreased development of Fusarium rot of gladiolus clones at least twice.

Kraft J.M., Plleger F.L. (eds.). 2001. Compendium of Pea Diseases and Pests. 2nd Edition. APS Press - The American Phytopathological Society. St. Paul, Minnesota, USA. 67 pp. ISBN 089054-269-4.

Ash Cynthia L. (ed.). 2001. Shade Tree Wilt Diseases. APS Press - The American Phytopathological Socicty, St. Paul, Minnesota 257 pp. ISBN 0-89054-277-5.

The content and composition of glucosinolates in green parts of mustard plant iSinapis alba L.), at different stages of plant development were analysed. Four mustard varieties: Salvo, Metex, Ascot and Nakielska were taken under consideration. It was stated that in green parts of mustard sinalbin was dominating component of glucosinolates, but also glucotropeolin and small amounts of glucobrassicanapin apeared. The content of these compounds changes during vegetation and it is different in particular plant organs. Biological activity of mustard glucosinolates towards cabbage aphid was also studied. The correlation between the content of glucosinolates in plant and its susceptibility to aphid iBrevicoryne brassicae L.) infestation was checked. It was found that higher level of glucosinolates in plant caused some limitation of this pest development. Also the activity of water and alcohol extracts from mustard leaves was tested in relation to cabbage aphid. Disadvantageous influence of these extracts on aphids' survival was observed and this effect depended on extracr's concentration.

The development of spider mite populations (T urticae and T cinnabarinus) as well as plant injuries on different croton cultivars were studied. Observations were conducted in commercial and experimental glasshouse conditions. The highest spider mite populations were noticed on cultivars Norma and Petra, the lowest on Golden Sun. Tetranychus urticae was the dominant species in commercial glasshouses. Croton cv. Norma was severely injured by T urticae. The leaf damage index (LOI) for this cultivar was almost 4 after sixteen weeks of mite infestation.

In 1997, supplying Plant Pathogenic Microorganism Collection, microflora of diseased root crops from field and storage was analyzed. Samples from Districts Inspectors of PIOR from area of Poland were received, and 139 isolates of fungi from 369 samples of sugar and forage beat, forage cabbage, forage carrot and potatoes were obtained. The most often fungi from genus Fusarium occurred, and 23.5% of isolates from beet, 14.2% from cabbage, 29.5% from carrot and 48,2% from potatoes were received. The second dominant was species Alternaria a/terna ta, isolated from diseased plants in 28.9%, 50%, I 8.5% and 20% respectively. Among saprophytic fungi, species Penicillium and Aspergillus were represented in 9,7% of obtained isolates. Received results suggested that Fusarium spp. and Alternaria a/tema/a could be potentially dangerous for root crops as a pathogens or weak pathogens.

The effectiveness of 25 fungicides in the control of Sphaerotheca pannosa var. rosae were tested on 10 cultivars of roses. Also their influence on plant growth and eventual phytotoxiciry were assessed. The treatments were performed 4 times at weekly intervals. Shrubs treated with Folicur BT 225 EC, Spartak Alpha 380 EC, Sys thane MZ 61 WP, Systhane 125 EC, Tango 500 SC and To pas MZ 61 WP did not show disease symptoms. Bravo 500 SC, Folpan 80 WG, Funaben 50 WP, Penncozeb 80 WG and Saprol 190 EC were slightly less effective than the other tested fungicides. The influence of chemicals on plant growth was closely correlated with cultivar - showing stimulatory. inhibitory or neutral effects. Out of tested preparations Afugan 30 EC, Opus 125 SC and Tango 500 SC were strongly phytotoxic at used doses toward all rose cultivars. The intensity of damage depended on cultivar.

Monitoring of aphids - vector of potato diseases virus - continued in Poland for 30 years in 5 localities, indicated some changes in pressure exerted by these insectes. The biggest differences were observed for Macrosiphum euphorbiae (Thom.) and subsequently for Aphis frangulae Kalt. and Aulacorthum so/ani Kalt. Reduction in population of these aphids has been observed according to elapsing time in all five localities. In case of Myzus persicae (Sulz.) or Aphis nasturtii Kalt., these changes involved decrease or increase of the pressure, depending on the locality.

In 1997-1998 the effect of manure. straw and mustard on fungi parasitization of eggs of beet cyst nematode in three years sugar beet rotation was investigated. The highest eggs parasitization by fungi was observed inside cysts from plots with spring barley cultivation and sugar beet as a forecrop. Straw fertilizer favored more fungi parasitization than manure. Three species of nematophagous fungi were isolated from eggs: Cylindrocarpon desiructans. Paeci/omyces lilacinus and verticillium chlamydosporium

Inoculation of tobacco cv. Xanthi nc or bean plants with the mixtures of benzothiadiazole (Bion) and tobacco mosaic tobamovirus (TMV) or alfalfa mosaic virus (AIMV), respectively did not show any inhibition of the number and size of the local lesions. Protective treatment of plants with Bion caused a significant decrease in disease incidence. In the case of tobacco cv. Xanthi nc and TMV or bean plants and AIMV that protective effect increased day by day and 6-7 days after treatment the production of local lesions was inhibited almost completely. Bean plants treated with Bion demonstrated resistance ranging between 60-90% also in nontreatcd parts. Bean and tomato plants pretreated with O.Ol% Bion were effectively (in 60-70%) protected against systemic infection by tomato black ring ncpovirus (TBRV).

The influence of PGPR on the susceptibility of glasshouse cucumber and tomato to spider mites was studied. It was found that plants treated with PGPR suppressed the development of mite populations on both studied crops. The effect was more evident for cucumber, as compared to tomato plants. Mite population was smaller by more than 40% on the leaves of the susceptible cucumber cultivar, Corona growing in the presence of rhizobacteria, as compared to that without bacteria. The development of spider mite population on the bacterized susceptible tomato cultivar, Romatos was more inhibited on young leaves (43%) than on older ones (34%). As the injury of plants progressed the level of inhibition was decreased.

On the basis of sweep netting samples and young plant and spike samples, the species composition and the incidence of thrips (Thysanoptera) on rye and winter wheat in different regions of Poland have been determined. A list of 49 Thysanoptera species found on these cereal crops and an overview of 11 species referred to "cereal thrips" have been given. The undertaken studies have showed that Haplothrips aculeatus Fab. was dominant on both rye and winter wheat crops.

The aim of the experiment was to assess the susceptibility of buckwheat grains and products to the infestation by Trogoderma granarium Everts. The observations were conducted on three buckwheat cultivars: Hruszowska, Emka and Kora. The results suggest that buckwheat grains and products as suitable for the development of the first larval stages of Trogoderma granarium as wheat grain and wheat flour. However. extension of the development stage on buckwheat seems to indicate that the seed cover inhibits the capacity of larvae to feed on buckwheat.

Ustinov, I.D., Movchan O.M., Kudina Zh.D. 1995. Karantin Roslin: 1 - Karantinni Szkidniki [Plant Quarantine: 1 - Quarantine Pests]. Iris, Kiev, 416 pp. ISBN 5-7707-8165-3. (In Ukrainian).

Duveiller E., Dubin H.J., Reeves J., McNab A. (rds.) 1998. Helminthosporium Blight ofWheat: Spot Blotch and Tan Spot. CIMMYT, UCL, BADC, Mexico 376 pp. ISBN 970-648-001-3.