Control of mildew in vines with cinnamon extract and catalase activity in organic production

Abstract

Management with synthetic fungicides in the control of phytopathogens in viticulture can cause environmental pollution and contamination with residues in grape cluster. The objective of this study was to verify the effect of aqueous cinnamon extract on the in vitro and in vivo control of Plasmopara viticola on catalase activity on ‘Isabel Precoce’ vines. The treatments used were: aqueous cinnamon extract (ACE) at concentrations of 0.12; 0.25 and 0.50% plus 0.25% vegetable oil (VO); being the standard treatments VO (0.25%), Bordeaux mixture 1:1:100 (lime: copper sulfate: water) and water only. The germination tests of P. viticola sporangia were carried out in incubation periods of 4 and 24 hours of the pathogen in contact with the treatments. In addition, the area under the disease progress curve (AUDPC) and the activity of the catalase enzyme were estimated in plants grown in the greenhouse. The results indicated that the treatments with 0.12%, 0.25% and 0.5% ACE with VO reduced the germination of P. viticola. In relation to the AUDPC, the 0.25% dose of VO associated ACE reduced 65% and 67% in leaf discs and vines in the greenhouse, respectively. This fact is related to the induction of CAT activity provided by this dose in the periods of 2HBA, 2HAI and 4HAI. Thus, it can be said that the ACE associated with VO can be used to control the downy mildew of the ‘Isabel Precoce’ vine.

Activity of Aqueous Extracts from Native Plants of the Yucatan Peninsula against Fungal Pathogens of Tomato In Vitro and from Croton chichenensis against Corynespora cassiicola on Tomato

“…In controlling leaf spots in tomato, the aqueous extract of C. chichenensis roots reduces the speed of symptom development over time, resulting in a large difference in severity. In other greenhouse studies, an aqueous extract of Ocimum basilicum at 10% ( w / v ) reduced by 43% the calculated rate of disease caused by C. cassiicola [ 67 ]; an aqueous extract of cinnamon at 0.25% ( w / v ) reduced the severity of grapevine downy mildew caused by Plasmopara viticola by 67% [ 68 ]. Volatile metabolites from the leaves of Solanum habrochaites (LA1777) reduced the severity of the late blight of tomato caused by Phytophthora infestans EG_7 by 97% and lowered the AUDPC [ 69 ].…”

Comparative Physiological and Transcriptomic Analyses Reveal Mechanisms of Exogenous Spermidine-Induced Tolerance to Low-Iron Stress in Solanum lycopersicum L

“…Then, homogenate centrifugation was done at 12,000× g for 15 min at 4 °C. The supernatant was used to determine the peroxidase (POD) [ 31 ], catalase (CAT) [ 32 ] and superoxide dismutase (SOD) [ 33 ] activity. Activity analyses of POD, CAT and SOD were performed as described previously [ 34 ].…”

“…A fresh-leaf or root sample (0.3 g) was placed in a pre-cooled pestle and mortar and ground to a fine frozen powder under liquid nitrogen, followed by homogenization in 3 mL 50 mM phosphate buffer (pH 7.8) in an ice bath. Then, homogenate centrifugation was done at 12,000× g for 15 min at 4 • C. The supernatant was used to determine the peroxidase (POD) [31], catalase (CAT) [32] and superoxide dismutase (SOD) [33] activity. Activity analyses of POD, CAT and SOD were performed as described previously [34].…”

Melatonin Alleviates Copper Toxicity via Improving ROS Metabolism and Antioxidant Defense Response in Tomato Seedlings

“…Peroxidase (POD) activity was calculated using guaiacol as described previously [38]. The activity of catalase (CAT) was determined according to the methodology described previously [39]. Ascorbate peroxide (APX) activity was calculated using a spectrophotometer at 290 nm as described by Nakano and Asada [40].…”