Powdery mildew of wheat, caused by Blumeria (= Erysiphe) graminis f. sp. tritici (anamorph: Oidium monilioides), is recognized as one of the main wheat diseases. Present control measures against this pathogen are based on the use of fungicides at the preflowering stage. In order to find new ecocompatible control methods against wheat powdery mildew, the yeasts Rhodotorula glutinis (isolate LS11) and Cryptococcus laurentii (isolate LS28) and the yeast-like fungus Aureobasidium pullulans (isolate LS30), previously selected and tested for their wide range of activity against different fungal pathogens, were evaluated. In a two-year experiment carried out in wheat fields of the Molise region, the biocontrol agents (BCAs) were applied alone or in combination with a low dosage of common fungicides or with natural adjuvants. Treatments were applied by spraying them twice at (i) flag leaf stage and (ii) pre-flowering stage. Percentage of infected leaves, disease severity and the population level of BCAs on the leaves were periodically assessed and the data were subjected to variance analysis. Results showed that the highest protection from powdery mildew was given by BCAs applied in combination with some adjuvants (i.e. calcium citrate, calcium chloride, calcium propionate, soybean oil and humic acid) as well as with a low dosage of fungicides. Moreover, highest levels of the antagonist population were found on leaves treated with BCAs plus mineral salts.
Biological and integrated control of wheat powdery mildew
DE CURTIS, Filippo;LIMA, Giuseppe;
2007-01-01
Abstract
Powdery mildew of wheat, caused by Blumeria (= Erysiphe) graminis f. sp. tritici (anamorph: Oidium monilioides), is recognized as one of the main wheat diseases. Present control measures against this pathogen are based on the use of fungicides at the preflowering stage. In order to find new ecocompatible control methods against wheat powdery mildew, the yeasts Rhodotorula glutinis (isolate LS11) and Cryptococcus laurentii (isolate LS28) and the yeast-like fungus Aureobasidium pullulans (isolate LS30), previously selected and tested for their wide range of activity against different fungal pathogens, were evaluated. In a two-year experiment carried out in wheat fields of the Molise region, the biocontrol agents (BCAs) were applied alone or in combination with a low dosage of common fungicides or with natural adjuvants. Treatments were applied by spraying them twice at (i) flag leaf stage and (ii) pre-flowering stage. Percentage of infected leaves, disease severity and the population level of BCAs on the leaves were periodically assessed and the data were subjected to variance analysis. Results showed that the highest protection from powdery mildew was given by BCAs applied in combination with some adjuvants (i.e. calcium citrate, calcium chloride, calcium propionate, soybean oil and humic acid) as well as with a low dosage of fungicides. Moreover, highest levels of the antagonist population were found on leaves treated with BCAs plus mineral salts.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.