Louise Larissa May De Mio

Extratos, decoctos e óleos essenciais de plantas medicinais e aromáticas na inibição de Glomerella cingulata e Colletotrichum gloeosporioides de frutos de goiaba

The main disease of the guava (Psidium guajava L.), after harvesting, is anthracnose, caused by Glomerella cingulata and Colletotrichum gloeosporioides. This pathogen and chemical residues of fungicides in fruits are considered the mains problems for exportation. In this work was evaluated the fungitoxic effect of extracts, decoctions and essential oils of medicinal and aromatic plants in the mycelium growth of the pathogens, in vitro, to be recommended as an alternative to chemical control in postharvest. To prepare the aquous extracts a 10% and the decoctions (sub-products of hydrodistillation) were added in PDA medium, autoclaved and distributed into Petri dishes. The essential oils were added in three equidistant points by Petri dishes contening PDA medium. Discs of the isolates of the pathogen were placed on the center of the Petri dishes. The fungitoxic effect was evaluated by measuring the diameter of the colonies when the pathogens or any other treatment reached the border of the Petri dishes. The aquous extract and the essential oil from the clove inhibit in 100% of G. cingulata and C. gloeosporioides growth, and the last one was totally inhibited by the essential oil of the lemon grass. The decoctions of rosemary, ginger, calendula, orange (Citrus sinensis) showed inhibition potencial to control both isolates of the pathogen. In the control of C. gloeosporioides also had good results the decoctions of mayweed, chamomile and tagetes. The total or partial mycelium growth inhibition of the Glomerella cingulata e Colletotrichum gloeosporioides showed the existence of compounds biologically actives with fungitoxic effect, in the extracts, decoctions and essential oils of medicinal and aromatic plants. This indicated a potential application of this products as an alternative to control anthracnose in guavas fruits.

Comportamento pós-colheita de frutos de morangueiro após a aplicação pré-colheita de quitosana e acibenzolar-S-metil

ABSTRACT - The use of inductors of resistance in plants represents an alternative and a promising method to control fruit rots at postharvest. The experiment was carried out at Federal Technological University of Parana - Dois Vizinhos - Campus, during 2004 wit h theobjective to evaluate the induction of chitosan resistance and acibenzolar-S-methyl (ASM) on strawberry plants. The treatmentscompared the effect of chitosan (0.5; 1.0 and 2.0%) and ASM (0.0025%) in relation to control plants (distilled water only) and those withfungicides application. The chitosan treatment in all three evaluated concentrations, delayed the fruit maturation, increased the fleshfirmness and titratable acidity and decreased the mass loss. It was also observed reduction in the ethylene production and in thereduced sugars and increased the total polyphenol in strawberry fruits. The chitosan treatment in all three evaluated concentrationsinduced greater plant resistance to diseases with effect on the reduction of the fruit rots in the post harvest by Botrytis cindered.Although, chitosan treatment in the concentration of 2% caused damage to the fruits in the post harvest increased the respiration rateand the reduced sugar. The ASM had effect on the retention of the titratable acidity and acted efficiently on the rot reduction similar tothe treatment with fungicides. The application of chitosan and ASM pre-harvest did not interfere in the organoleptic quality of the fruitsin the post harvestIndex Terms: elicitor, ASM, chitosan, strawberry, quality, Botrytis cinerea.

Avaliação de atrativos alimentares utilizados no monitoramento de mosca-das-frutas em pessegueiro na lapa- PR

Fruit flies of Anastrepha genus are a key pest in peach trees in Parana. Food attractants were tested to determine their efficiency in monitoring fruit flies captured in McPhail fly traps. The experiment was conducted over a period of three years. In 2002 the following attractors were tested: Maguari® brand grape juice, BioAnastrepha® brand hydrolyzed enzymatic protein and Chemin Agrin® vinegar. Over the next two years, the vinegar was replaced by Torula® hydrolyzed protein compound. Protein-based attractants were the most efficient in trapping Anastrepha spp. and captured flies earlier comparing to grape juice. According to the results, the use of protein-based attractants for monitoring Anastrepha spp in the Lapa peach trees was recommended.

Escala diagramática para avaliação da severidade da mancha-de-micosferela em morangueiro

A diagramatic scale with five levels of disease severity: 0.11; 0.51; 2.4; 10.2 and 34.9% was developed and validated to assess mycosphaerella blight in strawberry, caused by Mycosphaerella fragariae. The scale was developed considering the maximum and minimum limits of disease severity observed in the field and the intermediate values followed logarithmic increments according to the Stimulus Law by Weber-Fechner. Initially the estimates of severity were performed without the use of the scale in 30 leaves with different levels of severity. Validation was carried out by seven appraisers, without previous pratice in assessing mycosphaerella blight in strawberry. Then, the appraisers estimated the severity of the same leaves previously assessed using the proposed diagrammatic scale. Assessments with the diagrammatic scale were of great precision for all raters and did not constitute systematic mistakes in over or underestimating the disease severity. The proposed diagrammatic scale was considered adequate to estimate mycospharela blight severity in strawberry.

Development and validation of a standard area diagram set for assessment of peach rust

The aim of this study was to develop and validate a standard area diagram set (SADs) to assess the severity of peach rust, caused by Tranzschelia discolor. The proposed SADs includes ten images of leaves with a range of severity (0.1, 0.5, 1.0, 2.0, 5.0, 10, 15, 20, 25 and 30%). The SADs was validated by 14 raters who had no experience in plant disease severity estimation. In the first step of the validation, the raters made severity estimates of 50 leaves with a range of rust severity without using SADs. In the second step, the same raters estimated severity of rust on the same 50 leaves using the SADs to aid estimation. Lin’s concordance correlation analysis showed that both precision and accuracy improved when the raters used the SADs compared to the assessments made without SADs. Accuracy, as measured by the coefficient of bias (Cb) improved from 0.70 to 0.98, without and with SADs, respectively, and precision measured by the correlation coefficient (r) improved from 0.85 to 0.90, without and with SADs, respectively. Overall agreement, measured by Lin’s concordance correlation coefficient (ρc), improved from 0.59 to 0.88 without and with SADs, respectively. Furthermore, estimates were more reliable when using SADs: the coefficient of determination (R2) was 0.60 without and 0.73 with SADs; and the intra-class correlation coefficient (ρ) was 0.72 without, and 0.86 with SADs. Thus, the use of SADs improved the precision, accuracy and reliability of visual estimates of severity of peach rust.

Glomerella leaf spot in apple: validation of proposed diagrammatic scale and efficiency of fungicides

A diagrammatic scale to assess Glomerella leaf spot severity (Colletotrichum spp) was developed and validated during the tryout of a fungicide efficiency experiment in the field. Apple leaves were collected for determination of minimum and maximum severity limits; intermediate levels were obtained according to Weber-Fechners stimulus-response law. Scale validation was performed by four raters, which estimated the severity in 100 leaves; with and without the use of the scale. An experiment was carried out in a commercial orchard in randomized blocks with 10 plants. The treatments and dosages (g 100 L-1 of water) used were: cyprodinil (15); pyrimethanil (30, 37.5, 45); propineb (140) e mancozeb (160) + tebuconazole (12.50), and a control (no spray). The incidence and severity in leaves; number of fruits, weight and incidence in fruit (harvest) and defoliation (after harvest) were evaluated. The proposed scale showed the levels of 0.08; 0.28; 0.99; 3.45; 11.23 and 30.93%. The scale was adequate for severity assessment; R2 changed from 0.68 to 0.96 with the use of the scale. Pyrimethanil treatments did not control the disease. The incidence on fruit was 30 and on leaves 63%. The incidence was reduced in 35.6% (propineb) and 33.7% (mancozeb + tebuconazole) related to the control, these treatments were efficient to control the disease. The defoliation was 44 % in the control against 9.6 and 2.5% to propineb and mancozeb + tebuconazole.

Metodologia para detecção de infecções latentes de Monilinia fructicola em frutas de caroço

The brown rot fungus Monilinia fructicola is economically the most important pathogen for stone fruit trees. The fungus infects since blossoming and may remain latent in the fruits and manifest symptoms during harvest and postharvest. The present study aimed at evaluating methodologies to detect latent infections in developing fruits for different cultivars of stone fruit trees. Eight cultivars of stone fruit trees were chosen in order to evaluate latent infections of M. fructicola. For that purpose, 30 fruits of each cultivar were collected and separated into two batches of 15 fruits. One of them was subject to immersion for two minutes in a sequence of ethanol solution 70%, later, sodium hypochlorite 2%, and finally washed in sterilized water. The treatment for the second batch of fruits was similar to the first one, adding paraquat solution 2% (paraquat - 200g L-1, Gramocil-SC) after the hypochlorite. After the treatments, the fruits were laid in humid chamber in plastic packages containing humid filter paper at room temperature. The evaluation of the incidence of the disease was carried out every 48 hours for 10 days. The latent infections were detected in the majority of the cultivars evaluated with the two methods, mainly in the fruits closer to maturation. The treatment in which herbicide was used increased the detection of brown rot in the plum cultivars Reubennel and Harry Pickstone. For the peaches in cultivar BR-3, the two methods favored the detection; however, in the cultivars Chimarrita and Vila Nova there was higher detection of latent infection when paraquat was not utilized.

Comportamento fenológico e produtivo de cultivares de pessegueiro no município da Lapa, Paraná

O objetivo deste trabalho foi avaliar a fenologia e a producao de cultivares de pessegueiro, na Lapa, Estado do Parana. Foram avaliadas 11 cultivares, nas safras 2008/2009, 2009/2010 e 2010/2011: Aurora-1, Chimarrita, Chiripa, Coral, Eldorado, BRS Granada, BRS Leonense, Maciel, Marli, Premier e BRS Vanguarda. Utilizou-se o delineamento experimental de blocos ao acaso, com 11 tratamentos (cultivares) e tres repeticoes. Temperaturas mais baixas e chuvas no periodo de floracao atrasaram a colheita em quase um mes, nas cultivares de ciclos mais precoces. A frutificacao efetiva foi, em media, maior e mais constante na cultivar Chimarrita (81%). Houve reducao na eficiencia produtiva de todas as cultivares, a cada safra; maior nas cultivares BRS Leonense e Chiripa (acima de 90%) e menor na Chimarrita (61%). A cultivar Premier apresentou o ciclo mais curto (105 dias), e a Maciel o mais longo (145 dias). As cultivares Chimarrita, BRS Vanguarda, Eldorado, Maciel e Marli sao as mais produtivas. A cultivar Chiripa nao e adaptada a regiao.

Nitrogen and potassium fertilization affecting the plum postharvest quality

O objetivo foi analisar o efeito da adubacao com nitrogenio e potassio na qualidade pos-colheita de frutos de ameixa (Prunus salicina) armazenados sob baixa temperatura, durante 37 dias. Este experimento foi desenvolvido em um pomar com cinco anos de idade da cultivar Reubennel, situado no Municipio de Araucaria, Parana, Brasil, num Cambissolo Humico. Foram aplicados 55 e 110 kg/ha/ano de K2O, na forma de cloreto de potassio e nitrogenio, nas doses de 40; 80; 120; 160 e 200 kg/ha/ano, na forma de ureia, em esquema fatorial (2x5), em parcelas subdivididas. Cem frutos de cada parcela foram colhidos no mesmo dia, quando de 25 a 50% da casca apresentava coloracao amarelo-avermelhada. Os parâmetros avaliados foram: firmeza de polpa, solidos soluveis totais e acidez titulavel na colheita e depois de 17; 27 e 37 dias de armazenamento a 0 ± 0,5 oC. A qualidade dos frutos na colheita foi afetada somente pela aplicacao de N, com os melhores resultados na dose de 40 kg/ha/ano. A aplicacao de 40 kg/ha/ano de N e 110 kg/ha/ano de K permitiram que os frutos permanecessem com melhor qualidade durante o armazenamento. O armazenamento refrigerado nao deve exceder a 27 dias. A qualidade dos frutos de ameixa Reubennel depende das doses de N e K.

Danos de Grapholita molesta (Busck) (Lepidoptera: Tortricidae) em seis cultivares de pessegueiro em Araucária, Paraná

This paper deals with the occurrence and damage of Grapholita molesta (Lepidoptera: Tortricidae) in a commercial peach orchard with six cultivars of different fruit ripening cycles: precocious (Sao Pedro ), medium (Chimarrita , Ouro , Coral and Marli ) and late (BR II ), in Araucaria, State of Parana, Brazil. Five plants of each cultivar were selected for evaluating the damages in shoots and fruits. The damages were accumulated and evaluated in three phases: previous thinning, stone hardening and harvesting. The results were as follows: the cultivar Ouro was the most damaged one up to the harvesting phase, although Chimarrita surpassed Ouro when the damages observed in the post-harvesting phase were included. Among the six cultivars, Marli was the one presenting the highest number of damaged fruits.