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Leaf spot caused by the pathogenic fungus Cercospora beticola Sacc. is the most important disease of sugar beet. The disease is very aggressive to sugar beet and in favorable conditions it is expanding rapidly and can completely destroy sugar beet leaves. Plants, whose leaves were destroyed, are developing new leaves (retro-vegetation), however, they are worn out and result in lower yields and sugar digestion. Generally, the occurrence and intensity of the attack by this fungus mostly depends on weather conditions during summer growing period. The amount of damage depends on the resistance of the genotype and all provided agro-technical measures. Agro-technical protection measures include sowing healthy and with fungicide protected seeds, then, a proper crop rotation and the timely and proper execution of procedures including tillage, fertilization and weed protection. The use of fungicides in our terms of production is certainly necessary no matter if we are sowing sensitive or tolerant sugar beet hybrids. However, C. beticola is a parasite which has high possibility to develop resistance to fungicides (8, 9). The reduced susceptibility or resistance is reflected in the reduced effectiveness of fungicides to control leaf spots and is recorded in almost all countries where this disease is important. Resistance or reduced susceptibility of these pathogenic fungi to fungicides is related to the mass application of systemic fungicides, particularly from the group of strobilurins The research was conducted during 2014 and 2015, on Mollic Gleysols and Eutric brown soil. The experiment was set up in a split-block scheme with 14 different variants in 4 repetitions: A. soil type (A1 – Mollic Gleysols ; A2 – Eutric brown soil) ; B. treatment with fungicides (B1 – control ; B2 – one time during vegetation – Rias 300 EC, 0.35 l/ha ; B3 – one time during vegetation – Bravo 720 SC, 1.5 l/ha ; B4 – one time during vegetation – Sphere 535 SC, 0.35 l/ha ; B5 – two times during vegetation – Rias 300 EC, 0.35 l/ha + Duett ultra, 0.6 l/ha ; B6 – two times during vegetation – Bravo 720 SC, 1.5 l/ha + Duett ultra, 0.6 l/ha ; B7 – two times during vegetation – Sphere 535 SC, 0.35 l/ha + Duett ultra, 0.6/ha). The best results in all investigated parameters were obtained in variant B5 (two times during vegetation – Rias 300 EC, 0.35 l/ha + Duett ultra, 0.6 l/ha) and B6 (two times during vegetation – Bravo 720 SC, 1.5 l/ha + Duett ultra, 0.6 l/ha). In addition to the control variant (B1), the worst results were achieved in variant B4– one time during vegetation – Sphere 535 SC, 0.35 l/ha.

Cukrová řepa má ve srovnání s jinými plodinami velmi vysoké agrotechnické požadavky. Hnojení je jedním z nejdůležitějších agrotechnických zásahů a klíčovým prvkem dodávaným hnojivy je dusík. Dusík je pro výživu řepy velmi významný. Ovlivňuje nejen výnos, ale také kvalitu kořenů. Řepa jej přijímá ve značném množství, ale optimální rozsah dávky je omezen. Výzkum probíhal na dvou půdních typech, hnědozemi a organogenním gleji, v letech 2013 a 2014, v kompletně znáhodněném blokovém schématu ve čtyřech opakováních a 8 různých variantách ve 4 způsobech hnojení: A) Aplikace mikrobiologického preparátu (A1 – kontrola ; A2 – aplikace 30 l/ha) ; B) hnojeno dusíkem (B1 – kontrola ; B2 – hnojeno dle chemické analýzy ; B3 – hnojení sníženo o 30 % ; B4 – hnojení sníženo o 50 %). Nejlepších výsledků ve všech sledovaných parametrech bylo dosaženo při aplikaci mikrobiologického přípravku. U variant ošetřených biohnojivem bylo v obou letech, na obou půdních typech a u obou hybridů dosaženo nejlepších výsledků ve sledovaných ukazatelích u varianty se sníženým hnojením o 30 %. Ve většině případů nebylo dosaženo statisticky významných rozdílů mezi touto variantou a variantou, u které bylo hnojení sníženo na 50 %. Redukce hnojení dusíkem není významná jen z ekonomického hlediska, ale i ekologického. Vzhledem k tomu, že dusík je silně mobilní prvek, mohou jeho vysoké dávky unikat do podzemních vod a vést k jejich eutrofizaci.

Leaf spot caused by the pathogenic fungus Cercospora beticola Sacc. is the most important disease of sugar beet. The disease is very aggressive to sugar beet and in favorable conditions it expands rapidly and can completely destroy sugar beet leaves. Plants, whose leaves were destroyed, develop new leaves (retro- vegetation), however, they are weak and result in lower yields and sugar content. Generally, the occurrence and intensity of the attack by this fungus mostly depends on weather conditions during summer growing season. The amount of damage depends on the resistance of the genotype and all provided agro-technical measures. Agro-technical protection measures include sowing healthy and fungicide-protected seeds, a proper crop rotation and timely and proper execution of procedures including tillage, fertilization and weed protection. The use of fungicides in our terms of production is certainly necessary no matter whether we sow sensitive or tolerant sugar beet hybrids. However, Cercospora beticola is a parasite which has high possibility to develop resistance to fungicides. The reduced susceptibility or resistance is reflected in the reduced effectiveness of fungicides to control leaf spots and is recorded in almost all countries where this disease occurs. Resistance or reduced susceptibility of these pathogenic fungi to fungicides is related to the mass application of systemic fungicides, particularly from the group of strobilurins. The research was conducted in 2014 and 2015 on Mollic Gleysols and Eutric brown soil. The experiment was set up in a split-block scheme with 14 different variants in 4 repetitions: A. soil type (A1 – Mollic Gleysols ; A2 – Eutric brown soil) ; B. treatment with fungicides (B1 – control ; B2 – one time during vegetation – Rias 300 EC, 0.35 l ha–1 ; B3 – one time during vegetation – Bravo 720 SC, 1.5 l ha–1 ; B4 – one time during vegetation – Sphere 535 SC, 0.35 l ha–1 ; B5 – two times during vegetation – Rias 300 EC, 0.35 l ha–1 + Duett ultra, 0.6 l ha–1 ; B6 – two times during vegetation – Bravo 720 SC, 1.5 l ha–1 + Duett ultra, 0.6 l ha–1 ; B7 – two times during vegetation – Sphere 535 SC, 0.35 l ha–1 + Duett ultra, 0.6 l ha–1). The best results in all investigated parameters were obtained in variant B5 (two times during vegetation – Rias 300 EC, 0.35 l ha–1 + Duett ultra, 0.6 l ha–1) and B6 (two times during vegetation – Bravo 720 SC, 1.5 l ha–1 + Duett ultra, 0.6 l ha–1). In addition to the control variant (B1), the worst results were achieved in variant B4 – one time during vegetation – Sphere 535 SC, 0.35 l ha–1.

Dvogodišnji pokusi provedeni su na dva različita tipa tla (humoglej, eutrično smeđe tlo) tijekom 2013. i 2014. godine. Istraživan je utjecaj mikrobiološkog pripravka Terra Condi na infekciju patogenom gljivom Rhizoctonia solani Kuhn. Pokus je postavljen po randomiziranom blok rasporedu u 4 ponavljanja i 6 različitih varijanti koje su uključivale 2 tolerantna i 2 osjetljiva hibrida na ovu patogenu gljivu, te 2 različite varijante primjene mikrobiološkog pripravka. Uz kontrolu, tlo je predsjetveno tretirano mikrobiološkim pripravkom u količini od 30 l/ha. Na oba tipa tla, i u obje godine istraživanja, najmanji broj inficiranih i uginulih biljaka, kao i najveći prinos korijena i sadržaj šećera dobiveni su u varijantama gdje je apliciran mikrobiološki pripravak. //The two-year experiments were conducted on two different soil types (humogley, eutric brown soil) during two years, 2013 and 2014. The influence of microbiological preparation Terra Condi to the infection by pathogenic fungus Rhizoctonia solani Kuhn were investigated. The experiment was set up by randomized block design in 4 repetitions and 6 different variants that included 2 tolerant and 2 sensitive hybrids to this pathogenic fungus and 2 different variants of the application of microbiological preparation. In addition to the control, the soil was treated pre sowing by microbial preparation in an amount of 30 l/ha. The smallest number of infected and decayed plants, as well as the highest root yield, sugar content and pure sugar yield were obtained in variants with applied microbiological preparation, on both soil types and in both years of investigation.

Žuta ili crtičava hrđa (Puccinia striiformis f.sp. tritici) je u mnogim uzgojnim područjima pšenice destruktivna bolest, a u Hrvatskoj se do 2014. godine javljala sporadično. Razlozi pojave bolesti u izrazito jakom intenzitetu tijekom prošle vegetacije su: vrlo blaga zima, sjetva osjetljivih kultivara, stvaranje i širenje rasa gljive koje su jako agresivne i patogene (potvrđeno prisustvo izrazito agresivne Warrior rase u Hrvatskoj u 2014. godini) i neadekvatna zaštita fungicidima.