Organic fertilization and alternative products in the control of powdery mildew

Abstract

Rose is a plant of high nutritional requirement, susceptible to powdery mildew disease caused by fungus Oidium leucoconium, which causes leaf fall and losses in flower production. The objective of this study was to evaluate powdery mildew severity in rose cultivar ‘Grand Gala’ in response to organic fertilization and the application of alternative products to disease control. The first experiment was set in a factorial arrangement, with 5 alternative products: spraying with water as a control (PA), lime sulfur (CS), neem oil (ON), mixture of sodium bicarbonate and canola oil (BC) and coffee pyroligneous acid (APC) and 2 organic fertilizers: chicken manure (EA) and biofertilizer based on banana stalk (B). Disease severity was assessed at 0, 15, 30 and 45 days after the treatments. In the second experiment, asymptomatic leaves or with different powdery mildew severity levels were sprayed only once with the same alternative products mentioned above. Severity was assessed at 0, 7 and 14 days. The organic fertilizations did not influence the reduction in powdery mildew severity in rose. At 45 days, APC yielded a greater reduction in disease severity (81.6%), followed by treatments based on BC, ON and CS. Greater reduction in disease severity in experiment 2 occurred in the treatments of BC and CS, followed by APC. Therefore, it is possible to conclude that APC and the BC have the potential to control rose powdery mildew in an organic cultivation system.

Seed pretreatment for control of powdery mildew infection on purple ipe micropropagation

“…Neem oil as an alternate control agent has proven to be efficient, including for powdery mildew. The neem oil reduced powdery mildew severity in rose (Ramos et al, 2020), garden pea (Mishra et al, 2017) and in Cannabis sativa L. of over 50% (Scott and Punja, 2020). Spraying neem oil on C. sativa with powdery mildew was also efficient and the results did not differ statistically from that fluopyram treatment (Scott and Punja, 2020).…”

“…The purple ipe is widely used in the reforestation of degraded areas and urban landscaping owing to its recognized beauty (Chaves, 2018;Máximo, 2020). Furthermore, it is an arboreal species of economic value because of its wood presents good durability and resistance in addition to its ornamental and medicinal uses (Santos et al, 2020) and a source of β-lapachone, one medicinal component (secondary metabolite), present both in stem periderm and woody part, which has anti-inflammatory, analgesic, antibiotic and antineoplastic properties (Bang et al, 2016;Campanholi et al, 2018).…”

Phytohormonal and Transcriptomic Response of Hulless Barley Leaf in Response to Powdery Mildew Infection

“…The control of PM is achieved by the exogenous application of fungicides, particularly those based on sulfur. However, such methods have their own disadvantages in terms of disturbance to climate and pose ecological risks [7,8]. Apart from this strategy, the understanding of the genetic mechanism of resistance to PM and genetically modifying the specific genes is a long-term control strategy.…”