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Gray mold caused by Botrytis cinerea is an important disease in strawberries. This fungus causes significant economic losses since it attacks plants and fruits. In this context, this work aimed to evaluate the effectiveness of Acibenzolar-S-methyl (ASM) and Harpin protein in pre- and post-harvest as inducers of resistance in strawberries to B. cinerea. Strawberry plants (Fragaria x ananassa) from ‘Aromas’ and ‘Camarosa’ cultivars were grown in greenhouse and evaluated in laboratory. Doses of Harpin and ASM in pre- and post-harvest applications were assessed. Yield parameters of strawberry, B. cinerea incidence and injured area in fruit, fruit firmness, CO2 assimilation rate, and phenylalanine ammonia-lyase (PAL) activity were analyzed. Elicitors application in pre- and post-harvest conditions promoted a decrease of B. cinerea incidence and injured area in strawberry fruits. The results suggest that Harpin and ASM treatment show a significant impact on strawberry fruit disease. The control may be associated with the PAL induction, responsible for inducing defense responses. Harpin and ASM represent a promising alternative to synthetic fungicides for B. cinerea control during post-harvest storage.

Although small fruits, with some exceptions, are not yet as popular in Brazil, some farmers have invested in this market and the genus Physalis can be an important alternative source of income due to its high added value and possibility of cultivation in small areas. To date, there are no specific fertilizer recommendations for even the most cultivated species (Physalis peruviana) and therefore the goal of this study was to evaluate the effects of nitrogen fertilization on quality of fruits of Physalis peruviana and Physalis pubescens. Plants were grown in 5 L pots containing soil and maintained in a controlled environment, in greenhouse. Treatments consisted of five N levels (kg ha-1): 0, 200, 250, 300 and 350, with seven replicates per treatment. Variables evaluated were total soluble sugars and reducing sugars, phenolics, pH, titratable acidity and fruit diameter. Nitrogen increased soluble sugars (350 kg ha-1) and reducing sugars (300 kg ha-1), mainly in P. pubescens. There was a slight increase of juice pH, but concentrations of total phenols and citric acid decreased with increasing levels of N. Fruit diameter of the two species of Physalis was increased by N fertilization, and the best N level was 300 kg ha-1. Key words: Physalis peruviana, Physalis pubescens, reducing sugars, titratable acidity, total phenolics.

Made available in DSpace on 2022-04-30T08:00:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-04-01 The current work aimed at evaluating the influence of withholding irrigation on biomass production, content, yield and chemical composition of mint essential oil. The experimental design was completely randomized with five treatments and eight repetitions; totally forty plots; being conducted in pots inside a greenhouse for 58 days. The treatments consisted of withholding irrigation (NS) at different levels: control (daily constant irrigation at day zero by withholding irrigation), light NS (withholding irrigation for three days before harvesting), intermediate NS (withholding irrigation for six days before harvesting), severe NS (withholding irrigation for nine days before harvesting) and very severe NS withholding irrigation for twelve days before harvesting). Then, the following characteristics were evaluated: shoot fresh mass (SFM), shoot dry mass (SDM), root fresh mass (RFM), root dry mass (RDM), root volume (RV), conten, yield and chemical composition of mint essential oil. Results indicated that some characteristics were affected by withholding irrigation, such as SFM RFM, RDM, RV and some essential oil components (i.e. 3-octanol; linalool; limonene; p-cymen-8-ol; 3-octanol, acetate; cis-β-ocimene and cis-Piperitone epoxide). However, there was no significant difference between content and yield. Therefore, the current study showed that suppressing irrigation for 12 days before harvesting (very severe NS) did not affect plant development, since mint is commercialized in dry form. Department of Horticulture School of Agriculture Sao Paulo State University Plant Genetic Resources Center Agronomic Institute of Campinas (IAC) Department of Horticulture School of Agriculture Sao Paulo State University