In Poland, about sixty fungicides are registered for chemical protection of potato crops against late blight (Phytophthora infestans) and some of them are effective against early blight (Alternaria spp.). Time of appearance of pathogens in potato crops depends on climatic conditions. In Bonin climatic conditions in the years 1998-2002, early blight was observed at the earliest date i.e. 41-56 days after potato planting. Trials carried out at the Plant Breeding and Acclimatization Institute Bonin have shown different usefulness of fungicides in control of some pathogens of potato. The tested fungicides varied in their mobility (contact, translaminar, systemic) and activity against pathogens (protectant, curative, eradicative). All tested fungicides were effective in control of late blight in potato crops. They inhibited the rate of late blight development and in most cases the differences of their effectiveness were not significant. Systemic fungicides with slower mobility have the best efficacy in control of late blight infections occurring on potato stems. In laboratory tests, mancozeb, propineb and mixture of metalaxyl and mancozeb were significantly more effective in inhibiting the development of Alternaria. Fungicides, which are effective in the control of different pathogens, are particularly useful in potato protection programs.

The studies conducted in two different localities revealed variable time of occurrence and severity level of potato early blight (Alternaria spp.). Each year at Stare Olesno the early blight caused considerable destruction of potato plants (90.2%-95.4%) while at Bonin the disease severity differed in particular years and ranged from 50.0% to 97.5% of destructed plants at the end of the growing season. Field trials showed good efficacy of fungicides selected for controlling the early blight compared with an untreated control. Spraying with fungicides limited development of the disease and increased tuber yield in the range from 21.9% to 60.9% for Bonin and from 13.0% to 101.9% for Stare Olesno surveys. The mixture of zoxamide with mancozeb showed the greatest efficacy.

Investigation of leaf rust disease on spring crops of triticale (× Triticosecale Wittm.), it sdi stribution dynamics, as well as the efficacy of two fungicides, different application doses and timing was carried out at the Lithuanian Institute of Agriculture during 2000–2002. Differences in the disease development were determined by the meteorological conditions, especially the amount of rainfall, and growth stage of plants. Precipitation during 2000 was close to the mean, and the development of leaf rust was moderate. In June of 2001 the rainfall was twice as high as the norm, which created favourable conditions for pathogen development. In 2002 a long droughty period till flowering inhibited the development of leaf rust. The triazole fungicides Juventus (metkonazole 60 g l^–1) and triazole and strobilurine mixture. Allegro (kresoxim-methyl 125 g l^–1 + epoxikonazole 125 g l^–1) were used at full, two-third and half doses once and twice. Both of the fungicides were very effective against leaf rust. Biological efficacy of Juventus applied at any dose or time against leaf rust was 88.3%–99.7%. Allegro efficacy against this disease was slightly higher 94.7%–100%. Application of 1.0; 0.75 and 0.5 l ha^–1 doses twice showed a better efficacy than a single application. The higher doses of fungicides were not markedly superior to the lower ones.

Field trails were conducted to evaluate the economics of controlling cercospora leaf spot of groundnut using different fungicides. The experiments were laid out in a strip plot design with three replications at the Teaching and Research farm of the Department of Crop Protection, University of Maiduguri, sudan savanna of Nigeria during the 2002 and 2003 cropping seasons. Four fungicides namely: Benlate 50 WP, Trimangol 80 WP, Bentex T, and Ridomil 72 WP were applied as foliar sprays at three spray regimes while the control was left untreated. The application of the fungicides led to 20–50% reduction in the disease incidence and 15–22% reduction in disease severity and gave higher yield of seed and haulm than the control. The cost-benefit analysis revealed positive returns per hectare from the use of the fungicides for the control of disease in the study area. Application of Bentex T, for instance, gave 78.13% seed yield increase over the control which translated into a mean (two years) net profit of N52,267.50, N90,905.00 and N138,755.00 Nigerian Naira for one, two and three sprays, respectively, equivalent to $522.675, $909.05 and $1,387.55 per hectare. Even the least effective of the fungicides (Trimangol 80 WP) gave seed yield increase of 62.74% over the control which translated into a mean (two years) net profit of N41,287.50, N68,082.50 and N93,995.00 equivalent to $412.88, $680.83 and $939.95 per hectare for one, two and three sprays, respectively. Three sprays gave 115. 76% increase of yield over one spray and 39.35% yield increase over two sprays. These returns are attractive particularly to the farmers in the study area who grow the high yielding Ex-Dakar groundnut variety which is susceptible to cercospora leaf spot.

The effectiveness of 7 fungicides ( Amistar 250 SC, Bayleton 5 WP, Bumper 250 EC, Discus 500 WG, Folicur BT 225 EC, Folicur Multi 50 WG, Score 250 EC) and 2 bioproducts (Biochikol 020 PC and Biosept 33 SL) in the control of Puccinia pelargonii-zonalis was tested on pelargonium cv. Pulsar F1 Salmon. Additionally, their influence on plant growth, size of pustules, percentage of germinated spores and phytotoxicity were assessed. Plants were sprayed 4 times at weekly intervals. Among tested compounds the most effective in suppressing new uredia formation were Amistar 250 SC, Bayleton 5 WP, Biosept 33 SL, Bumper 250 EC, Folicur BT 225 EC and Score 250 EC. Furthermore, some fungicides inhibited germination of urediospores on PDA medium. Fourteen days after the last spraying more than 76% of germinating urediospores were found on control leaves. At the same time spores collected from plants protected with Amistar 250 SC, Bayleton 5 WP, Folicur BT 225 EC and Folicur Multi 50 WG germinated sporadically in 1.5 to 4.0%. In the next part of experiment, plants with visible sporulation of P. pelargonii-zonalis were sprayed with tested compounds. After 1, 7 and 14 days of incubation, total number of spores and number of germinating spores were counted. After 1 or 7 days, urediospores collected from untreated plants germinated in more than 80% whereas from plants sprayed with tested fungicides except Amistar 250 SC in 20–66.6%. Amistar 250 SC was the most effective in suppressing urediospore germination. All fungicides used in protection of young pelargonium plants, except Amistar 250 SC and Biochikol 020 PC, decreased plant growth. None of tested compounds showed phytotoxicity toward tested pelargonium cultivar.

The efficacy of Benlate 50 WP (benomyl), Bentex T (benomyl + thiram), Ridomil 72 WP (metalaxyl) and Trimangol 80 WP (maneb) applied as foliar spray in the control of cercospora leaf spot of groundnut in the sudan savanna of Nigeria was evaluated during the 2002 and 2003 cropping seasons. Three spray regimes (once, twice and thrice per season) were evaluated. Strip plot design with three replications was used in setting up the experiments. Ex-Dakar, a cercospora leaf spot susceptible groundnut variety was used as planting material. All the four fungicides significantly reduced the incidence and severity of cercospora leaf spot in both seasons. However, the application of Bentex T significantly better reduced the incidence and severity of the disease than the other fungicides. This was followed by application of Benlate 50 WP. Ridomil 72 WP and Trimangol 80 WP which gave moderate control of the disease. Three sprays with fungicides gave better control of the disease than one or two sprays in the season. The highest seed yield of 1 716 kg/ha and 2 263 kg/ha in 2002 and 2003, respectively, were obtained following treatment with Bentex T. The lowest yield of 962 kg/ha and 1 270 kg/ha in 2002 and 2003, respectively, were recorded from the control plots. Also the highest seed yield of 2 028 kg/ha and 2 672 kg/ha in 2002 and 2003, were obtained following three sprays compared to 939 kg/ha and 1 239 kg/ha in 2002 and 2003, respectively, for one spray in the season. The highest haulm yield of 6 131 kg/ha and 6 722 kg/ha in 2002 and 2003 was recorded from plots treated with Bentex T compared to 4 752 kg/ha and 5 166 kg/ha in 2002 and 2003, respectively, obtained from the control. Haulm yield of 6 355 kg/ha and 7 027 kg/ha in 2002 and 2003 were obtained following three sprays compared to 5 088 kg/ha and 5593 kg/ha in 2002 and 2003, respectively, recorded for the control. Bentex Tor Benlate 50 WP could be used to reduce the effect of cercospora leaf spot and improve groundnut production in the sudan savanna of Nigeria.

The influence of different nozzle types and adjuvants on the biological efficacy of fungicides in potato was investigated in four growing seasons in the years 1997-2000. The studied foliar plant disease was late blight (Phytophthora infestans). The biological efficacy of fungicides (alone or with adjuvants) applied with coarse air induction nozzles was comparable to fine standard flat fan nozzle. The differences between the nozzle types tested were small in control oflate blight in potato with systemic and contact fungicides. Coverage of upper side of leaf blades was from three to four times higher than lower side of leaf blades. In general, the highest coverage of upper and lower side of leaf was achieved when the full dosage rate of fungicide (copper oxychloride) was used with both the flat fan XR 110-03 and air induction DB 120-03 nozzle. Adding Atpolan 80 EC and Zero Piany 62 SL to 50% dosage rate of copper oxychloride decreased the spray coverage on lower side ofleaf as well as with both the XR 110-03 and DB 120-03 nozzles. However, addition of adjuvants to spray solution did not decrease the deposition on upper side of leaf blade. In general, adjuvants did not considerably influence the biological efficacy of the fungicide treatments sprayed with both the flat fan and the air induction nozzles but had favourable influence on potato yield.

The objective of the present study was to identify the dynamics of Alternaria blight spread on spring oilseed rape lower, middle and upper leaves and siliques, to determine the disease incidence (DI) and severity (DS) on leaves, stems, siliques and seeds under the effect of prochloraz and tebuconazole. Efficiency of the fungicides was compared in relation to their application time. Field experiments with the spring oilseed rape cv. 'Star' were conducted at the Lithuanian Institute of Agriculture during 1997-1999.

Research performed in the years 1999–2002 was carried out in Great Poland region on varieties of winter wheat Elena and Tercja. Experiments included three programmes of wheat cultivation: 1 – Conventional winter wheat protection based on recommendations for commercial fields; 2 – Integrated pest management programme where the control of diseases and insect pests was carried out on the background of thresholds of harmfulness/noxiousness, and weather forecasts; 3 – Untreated, without protection against diseases and pests. Two levels of nitrogen fertilization were applied in the experiments (120 kg N/ha and 170 kg N/ha) and the newest plant protection products were used for controlling fungal pathogens and noxious insects. The occurrence of diseases and insect pests, as well as beneficial entomofauna was determined in relation to each experimental variant, and occurring changes were analysed. Effectiveness of disease and pest control were calculated. Grain yield and its quality were determined and economical profitability for both conventional and integrated programmes calculated. It was shown that a high profitability can be obtained through the application of integrated pest management, as a result of correct choice and application of plant protection products, as well as proper choice of wheat cultivars and appropriate nitrogen fertilization.