Ivan Herman Fischer

Citrus postharvest diseases and injuries related to impact on packing lines

Brazilian exports of fresh citrus represent less than 1% of the overall Brazilian production. Phytosanitary barriers and poor appearance stand out among the several reasons contributing to such low exporting/production ratio. The purpose of this work was to characterize postharvest injuries in Valencia sweet oranges and Murcott tangors produced for foreign markets after different processing stages in a packinghouse, as well as to identify critical points and impact extent on packing lines. Sampling was performed both after pre-washing and degreening the fruits, and also at the arrival on the packing table and in the pallet. They were stored for 21 days at 25oC and 85% RH. The incidence of injuries was visually assessed every three days. An instrumented sphere with acceleration register was used to evaluate the extent of impacts (G, m/s2) at the 19 transference points of the citrus processing line. There was low rot incidence (under 3.5%) at the different stages of fruit processing, with slight increase after degreening in Valencia orange and a decrease after fungicides treatment in Murcott tangor. The main pathogens found in the oranges were Lasiodiplodia theobromae and Penicillium digitatum, which were surpassed by Colletotrichum gloeosporioides in the tangors. Impacts in the processing line were caused mainly by drops on hard surfaces, with 94.7% of them varying from 30 to 95 G. The greatest impacts were observed when fruits were transferred from the processing line to bins destined to degreening. Mechanical injuries related to oleocellosis increased until the arrival of fruits at the packing table.

Doenças e características físicas e químicas pós-colheita em maracujá amarelo de cultivo convencional e orgânico no centro oeste paulista

ABSTRACT-After harvested, yellow passion fruit have an increase in rot susceptibility and significant loss of fresh mass. Thepurposes of this work were to identify and quantify post harvest diseases and to evaluate the physical chemical characteristics ofyellow passion fruits grown under conventional and organic cropping systems. Fruits from both cropping systems were individuali zedand kept in a humid chamber for 24h, previously at 13 days period at 25±2oC and 70-80% RH. The incidence of diseases and theshrinkage index were visually assessed after fruit gathering and, then, every three days. Fruits were also characterized as to skinthickness, pulp content, titratable acidity and soluble solids content. There was high incidence of post harvest diseases in bothconventional and organic cropping systems. Anthracnose was the main disease, with 100% of incidence on fruits from both croppin gsystems, followed by Fusarium rot, with 25.5% in the conventional and 19.0% in the organic systems. Incidence of Phomopsis rot washigher in the conventional crop (11.0%) than in the organic crop (2.0%). Anthracnose severity was estimated using a diagrammaticscale, and corresponded to 34.1% in organic fruits and 39.8% in conventional ones. Organic fruits were bigger, and presented gr eaterskin thickness, less pulp content and greater soluble solids amount. Shrinkage indexes of fruit from both cropping systems did notdiffer. The results suggest the adoption of phyto sanitary control in the field and during post harvest stage aiming fruits with betterquality.Index Terms: Passiflora edulis, diseases, quality.

Desenvolvimento, produtividade e sobrevivência de maracujazeiro-amarelo enxertado e cultivado em área com histórico de morte prematura de plantas

The objective of this study was to evaluate the vegetative growth, yield and survival of yellow passion fruit (Passiflora edulis Sims) grafted on the three rootstocks in area with description of premature death of plants. The experiment was carried out in Adamantina, SP, Brazil, from May 2006 to February 2007, adopting the statistical design of randomized blocks, with three treatments and seven replications. The rootstocks evaluated were Passiflora edulis, P. alata and P. gibertii, using conventional cleft grafting. The variables evaluated were: stem diameter of the rootstocks, stem diameter of the grafts, length of internodes, length of the secondary branches, number of tertiary branches, number of fruits, average weight of fruits, diameter and length of fruits, yield and plant survival. The work demonstrated that the use of the grafting in yellow passion fruit is a viable option as vegetative propagation, as well as a means of controlling some soil pathogens, one problem that has limited the expansion of culture. It was observed that plants grafted on P. edulis presented better initial vegetative growth, followed of P. gibertii and of P. alata. The lowest yield was obtained in P. alata. It was observed that although the presence of Fusarium solani and Rotylenchulus reniformis in soil, 91% of the plants grafted on P. gibertii survival after 12 months of field planting, whereas in P. alata and P. edulis these indices were 60% and 8.6%, respectively, showing a bigger tolerance to the root diseases.

Avaliação de Passifloraceas, fungicidas e Trichoderma para o manejo da Podridão-do-colo do maracujazeiro, causada por Nectria haematococca

The low productivity of yellow passion fruit is due often to the phytosanitary problems, being the Collar rot caused by Nectria haematococca, one of the main problems in the majority of the producing States of Brazil. The disease control is basically preventive, avoiding the introduction of the pathogen in the area. So, the present work aimed at: a) evaluating the behavior of ungrafted yellow passion fruit cultivars Afruvec, IAC 275 and Maguary and Afruvec passion fruit grafted on five Passiflora species (Passiflora alata, P. maliformis, P. morifolia, P. mucronata and P. suberosa) in orchard where the disease is frequent; and b) evaluating the efficiency of chemical (copper oxychloride, prochloraz and thiabendazole) and biological products (Trichoderma harzianum and Trichoderma sp.) in the control of Collar rot in Afruvec yellow passion fruit in field conditions. Yellow passion fruit grafted on P. maliformis, P. suberosa and P. alata presented greater resistance to the Collar rot in relation to the ungrafted yellow passion fruit. The chemical and biological products applied to the base of plants (500 ml of volume) in monthly or biweekly intervals were not efficient in reducing the disease occurrence.

First report of Colletotrichum boninense infecting yellow passion fruit (Passiflora edulis f. flavicarpa) in Brazil

In June 2006, fruits of yellow passion fruit with typical anthracnose symptoms were collected in São Paulo state, Brazil. Based on cultural, morphological characteristics and molecular analyses of internal transcribed spacer rRNA region (ITS), the causal agent of the disease was determined as Colletotrichum boninense. This is the first report of C. boninense associated with anthracnose of passion fruit in Brazil.

Doenças pós-colheita em variedades de manga cultivadas em Pindorama, São Paulo

The present work aims to evaluate the occurrence of postharvest diseases of 15 mango varieties, cultivated in Pindorama, state of Sao Paulo, without chemical products. Fruits were individualized and kept in a humid chamber for 24 h, previously at nine days period at 25±2oC and 70-80% RH. The incidence of postharvest diseases and the severity of anthracnose were evaluated in three days intervals. At the beginning of the storage period, the fruits were also characterized as to soluble solids and titratable acidity content. Anthracnose was the main disease in the fifteen varieties of mangos, with 100% of incidence one day after harvest, followed by stem-end rot, with average among the varieties of 20.8% at the end of the storage. Smaller anthracnose severity was observed in the Surpresa and Zill varieties, while smaller incidence of the stem-end rot was observed in Winter and Pele de Moca varieties. Correlation analyses among the soluble solid and titratable acidity parameters of the varieties with the intensity of the anthracnose and stem-end rot were just significant only between acidity and anthracnose, before and after the storage period.

Physicochemical quality of Valencia sweet orange fruits from organic and conventional crops.

O presente trabalho teve como objetivo avaliar a qualidade fisico-quimica de frutos de laranja Valencia [Citrus sinensis (L.) Osbeck] provenientes de cultivos orgânico e convencional. Amostragens de frutos foram realizadas no periodo de julho a dezembro de 2008 e de 2009 em duas localidades, Borborema/SP e Itapolis/SP. Em cada localidade foram amostrados frutos de um pomar convencional e de um pomar orgânico. Imediatamente apos a colheita, os frutos foram avaliados quanto a qualidade fisico-quimica (massa, cor da casca, solidos soluveis, acidez titulavel, ratio e teor de acido ascorbico). Houve aumento do ratio (solidos soluveis:acidez titulavel) ao longo dos meses de colheita, o que retrata o processo de maturacao dos frutos. Considerando os frutos provenientes de Borborema/SP, observou-se que os frutos do sistema convencional apresentaram maior massa quando comparados aos do sistema orgânico. Em Itapolis/SP os frutos do pomar orgânico apresentaram melhor coloracao da casca em relacao aos do pomar convencional. As demais variaveis de qualidade avaliadas nao diferiram entre os sistemas de cultivo na maioria dos meses amostrados. Pelos resultados obtidos conclui-se que a qualidade fisico-quimica da laranja nao e afetada pelo sistema de cultivo, exceto a massa do fruto, que e menor quando proveniente de pomar orgânico, nos primeiros anos de producao.

Storage potential of W Murcott mandarin: refrigerated storage × modified atmosphere.

O objetivo do trabalho foi verificar a capacidade de conservacao refrigerada de tangerinas W Murcott submetidas a tratamentos com atmosfera modificada. Frutos dessa variedade foram tratados com cera e/ou acondicionadas em embalagens flexiveis XTend e mantidas a 10±1oC por periodos de ate 90 dias, em intervalos de 30 dias e, apos cada periodo, submetidas a temperatura ambiente (25±2oC) por sete dias para simular o periodo de transporte e comercializacao. Foram realizadas analises dos parâmetros fisico-quimicos dos frutos e tambem da incidencia de doencas no decorrer do armazenamento. O delineamento foi inteiramente casualizado em esquema fatorial. Os resultados obtidos foram submetidos a analise de variância e as medias comparadas pelo teste de Tukey (5%). A coloracao da casca das tangerinas, durante o armazenamento refrigerado, foi verificada no 30o dia de armazenamento a 10±1oC, com maior intensidade nos frutos do tratamento controle. Houve aumento do teor de solidos soluveis e reducao da acidez titulavel durante o armazenamento refrigerado das tangerinas, independente do tratamento. Os frutos (com ou sem cera) acondicionados em embalagem apresentaram menor perda de massa (<10%) ate o 60o dia de armazenamento refrigerado + 7 dias a 25±2oC. A incidencia de podridoes foi alta apenas nos frutos tratados com cera e acondicionadas em embalagem, apos a comercializacao simulada referente aos 90 dias de armazenamento refrigerado. Pelos resultados obtidos conclui-se que o acondicionamento de tangerinas em embalagem flexivel Xtend permite sua conservacao por ate 60 dias a 10±1oC seguidas de 7 dias a 25±2oC.

Identification of Botryosphaeriaceae species that cause stylar-end rot of guavas and characterisation of the disease monocycle

Guava (Psidium guajava L.) stylar-end rot is a serious postharvest disease of guavas in Brazil. The objective of this study was to identify the primary species of Botryosphaeriaceae that cause guava stylar-end rot and to evaluate the temperature and wetness conditions that are favourable for development of the disease monocycle of these pathogens in detached fruit. Morphological and phylogenetic analyses were performed for 56 monosporic isolates from Brazil. The species Botryosphaeria dothidea, Neofusicoccum parvum and Neofusicoccum ribis were identified as causal agents of the disease. Conidial germination of the three species was evaluated at various temperatures and wetness periods. Guava fruit were inoculated with a conidial suspension of each species. The inoculated fruit were maintained under various temperatures and wetness periods. The optimal temperatures for conidial germination were between 25 and 35xa0°C for each of these three species. At 30xa0°C, high germination rates were observed for the three species (70xa0%) under wetness periods longer than 6xa0h. The range of optimum temperatures for guava colonisation by the three species was 28 to 31xa0°C. However, the maximum diameter of the lesion was always smaller during the wetness period of 6xa0h compared to 48xa0h. The shortest incubation period of the disease was three days at 30xa0°C and was associated with the 48-h wetness period for the three species. The best conditions for disease development were high temperatures and prolonged periods of wetness. This report is the first to describe the association of N. parvum and N. ribis with guava fruits in Brazil.

Incidence of postharvest diseases on 'Kumagai' and 'Pedro Sato' guavas at wholesale markets in Brazil

The time after harvest is characterized by physiological changes in the fruit that favor the occurrence of postharvest diseases, which are often observed only after sale. As a result, the damage resulting from the action of quiescent pathogens can be underestimated. From November to April of the years 2009/2010 and 2010/2011, a survey was conducted to quantify the postharvest diseases in Kumagai and Pedro Sato guavas at two large wholesale markets in Brazil. The incidence of postharvest diseases differed significantly between the two cultivars evaluated. The most frequent postharvest diseases for Kumagai guavas were anthracnose, black spot and fusicoccum rot, ranging in incidence from 23.6 and 31.6%. For Pedro Sato guavas, the most frequent postharvest disease was anthracnose, with an incidence of approximately 72.3%.