Efficacy of fungicide mixture (pyraclostrobin + boscalid) in gray mold and downy mildew on lettuce

Abstract

In 2012, the biological effi cacy of the fungicide mixture pyraclostrobin + boscalid (Signum®, BASF ) in the control of two economically most important disease of lettuce, gray mold (B. cinerea ) and downy mildew (B. lactucae ), was tested. The experiments were conducted at the location of Belgrade (Ledine, Iceberg, salat center), and Smederevska Palanka (Experimental fi eld of the Institute of Vegetable Crops), by type of randomized block design with four replications (EPPO, 1997). Fungicide application was performed by a sprayer SOLO 423 with consumption of 400 l of water ha-1. A fungicide Signum®, (a.i. pyraclostrobin + boscalid) was applied in a dosage of 1.5 kg ha-1 and was carried out a total of four treatments of the growth stages starting when the plants had developed three leaves (BBCH 13). As the standard products at both locations the fungicide Sumilex SC 50 (a. i. procymidone), in the case of B. cinerea, and Ridomil MZ (a.i. metalaxyl + mancozeb), in the case of for downy mildew, were used. After manifesting clear distinguish between treated and untreated (control) plots, assessment of disease severity (60 plants per plot) and efficiency of fungicides were calculated. The fungicide mixture pyraclostrobin + boscalid, tested in this study, showed a high efficacy against downy mildew of lettuce, which amounted to 93.6 % (Location: Belgrade - Ledine) and 97.4 % (site: Smederevska Palanka) respectively. The effi ciency of the tested fungicide combination of suppression of gray mold was 92.5 % (location: Belgrade - Ledine) and 93.5 % (site: Smederevska Palanka), respectively.

U toku 2012. godine, vršena su ispitivanja biološke efi kasnosti kombinacije fungicida piraklostrobin + boskalid (Signum®, BASF) u suzbijanju dve ekonomski najvažnije bolesti salate, sive truleži (Botrytis cinerea) i plamenjače (Bremia lactucae). Ogledi su izvedeni na lokalitetima Beograd (Ledine, Iceberg salat centar) i Smederevska Palanka (Ogledne parcele Instituta za povrtarstvo), po tipu slučajnog blok sistema u četiri ponavljanja (EPPO, 1997; EPPO, 2002). Aplikacija fungicida vršena je pomoću leđne prskalice uz utrošak vode od 400 l/ha. Ispitivani preparat Signum®, primenjen je u dozi od 1,5 kg/ha, a obavljeno je ukupno četiri tretiranja, počevši od fenofaze kada su biljke imale razvijena tri lista (BBCH 13). Kao standardni preparati za poređenje, na oba lokaliteta, korišćeni su Sumilex 50 SC (a.s. prosimidon), u slučaju B. cinerea, odnosno Ridomil gold MZ (a.s. metalaksil + mankozeb), za suzbijanje prouzrokovača plamenjače. Nakon ispoljavanja jasnih razlika između tretiranih varijanti i kontrole, ocenjen je intenzitet oboljenja (60 biljaka po jednoj parceli) i izračunata efi kasnost fungicida. Primenom ispitivane kombinacije piraklostrobin + boskalid, ostvarena je visoka efi kasnost u suzbijanju plamenjače salate koja je iznosila 93,6 % (lokalitet: Beograd-Ledine), odnosno, 97,4 % (lokalitet: Smederevska Palanka). Efi kasnost ispitivane kombinacije u suzbijanju sive truleži iznosila je 92,5 % (lokalitet: Beograd-Ledine), odnosno 93,5 % (lokalitet: Smederevska Palanka).