ABSTRACT The objective of this work is to evaluate the use of modified atmosphere and chitosan as an alternative to chemical treatment in postharvest conservation of ‘Tainung 1’ papaya under refrigeration. The experiment comprised of completely randomized blocks with four replications, one fruit per replication, with a 2 × 4 × 4 factorial design as follows: two types of packaging (with or without polyvinyl chloride [PVC] stretchable film, thickness of 17 µm), four treatments (control, 2% chitosan, 4% chitosan, and prochloraz fungicide with 33.75 g a.i.·100 L–1), and four storage periods (0, 7, 14, and 21 days) at 10 °C and relative humidity (RH) of 90 ± 5%. The variables evaluated were mass loss (ML), external appearance, titratable acidity (TA), soluble solids (SS), vitamin C, reducing sugars (RS), and total sugars (TS). The storage of ‘Formosa’ papaya under refrigeration at 10 °C and RH of 90 ± 5% associated with PVC provided a low percentage of ML and longer conservation time of apparent quality (up to 7 days) in relation to fruits with no storage in PVC. The external appearance of fruits was preserved for up to 14 days by the PVC + 4% chitosan treatment and for up to 21 days by the PVC + prochloraz fungicide treatment. The treatment PVC + 4% chitosan associated with refrigeration is efficient in maintaining fruit quality. It is, for up to 14 days, a viable alternative to the use of prochloraz fungicide for postharvest conservation of ‘Formosa’ papaya.

RESUMO O uso excessivo de produtos químicos na cultura do mamão (Carica papaya) coloca em risco a eficácia de fungicidas, em razão dos problemas de resistência dos patógenos a esses produtos, além da possibilidade de resíduos tóxicos colocarem em risco a saúde humana e o ambiente. Diante disto, o presente trabalho teve por objetivo avaliar a eficácia de produtos naturais no controle de Colletotrichum gloeosporioides, in vitro e in vivo. No ensaio in vitro, avaliou-se os extratos aquosos de cravo-da-índia (Syzygium aromaticum) e canela (Cinnamomum zeylanicum) a 15%, quitosana 4%, isoladamente, a associação desses extratos de plantas com quitosana a 4% e, também, o fungicida procloraz (100 mg L-1), adicionados ao meio de cultura BDA, quanto ao efeito sobre o crescimento micelial do fungo, mantendo-se uma testemunha sem adição de produtos. O tratamento com o extrato aquoso de cravo-da-índia a 15% e sua associação com a quitosana, inibiram o crescimento micelial. A associação de quitosana com o extrato aquoso de canela foi mais eficaz na redução do crescimento micelial do que os dois isoladamente. No ensaio in vivo, os frutos de mamoeiro Formosa foram submetidos aos tratamentos por imersão: 1 – Testemunha (água destilada); 2 Testemunha – fungicida procloraz (Sportak® 450 EC) na concentração de 0,75 mL L-1; 3 – quitosana (4%); 4 – extrato aquoso de cravo-da-índia (10%); 5 – extrato aquoso de canela (30%); 6– extrato aquoso de cravo da índia (10%) + quitosana (4%); 7 – extrato aquoso de canela (30%) + quitosana (4%). Após 24h, os frutos foram inoculados com C. gloeosporioides e avaliados quanto à severidade da doença a cada dois dias. Observou-se, que apenas na terceira avaliação, os tratamentos com fungicida e extrato aquoso de canela a 30% associado à quitosana a 4% reduziram a severidade da doença, comparados à testemunha. Avaliando-se a área abaixo da curva de progresso da doença, observou-se que o tratamento com extrato aquoso de cravo também foi eficaz em reduzir a severidade da antracnose nos frutos.

ABSTRACT Excessive use of chemicals in papaya (Carica papaya L.) crops puts the efficacy of fungicides at risk because of the resistance problems of pathogens to these products, besides the possibility of toxic residues endangering the human health and the environment. Therefore, the present study aimed to evaluate the efficacy of natural products in controlling Colletotrichum gloeosporioides in vitro and in vivo. In the in vitro assay, the evaluated products were aqueous extracts of clove (Syzygium aromaticum) and cinnamon (Cinnamomum zeylanicum) at 1.5% and chitosan at 4%, separately, and the association of these plant extracts with 4% chitosan, as well as the fungicide prochloraz (100 mg L-1), added to PDA culture medium; they were evaluated for their effect on the mycelial growth of the fungus, maintaining a control without addition of products. The treatment with aqueous extract of clove at 15% and its association with chitosan inhibited mycelial growth. Association of chitosan with aqueous extract of cinnamon was more effective in reducing mycelial growth than the two products used separately. In the in vivo test, papaya ‘Formosa’ fruits were subjected to the following treatments by immersion: 1 - control (distilled water); 2 - control - fungicide prochloraz (Sportak® 450 EC) at a concentration of 0.75 mL L-1; 3 - chitosan (4%); 4 - aqueous extract of clove (10%); 5 - aqueous extract of cinnamon (30%); 6 - aqueous extract of clove (10%) + chitosan (4%); 7 - aqueous extract of cinnamon (30%) + chitosan (4%). After 24h, fruits were inoculated with C. gloeosporiodes and evaluated for the disease severity at every two days. Only in the third evaluation, treatments with fungicide and aqueous extract of cinnamon at 30% associated with chitosan at 4% reduced the disease severity, compared to control. The area under the disease progress curve indicated that the treatment with aqueous extract of clove was also effective in reducing the severity of anthracnose in fruits.

RESUMO: Este trabalho teve por objetivo avaliar, in vitro e in vivo, a eficácia de produtos naturais no controle da antracnose do mamão. Os experimentos in vitro foram instalados em delineamento inteiramente casualizado, sendo para a avaliação de crescimento micelial considerado o esquema fatorial 10 × 4 (tratamentos x períodos de avaliação) com oito repetições, com a esporulação avaliada ao final do experimento. Os tratamentos utilizados foram: extrato aquoso nas concentrações de 5 e 15% de Syzygium aromaticum (L.) Merr. & Perry (cravo-da-índia), Cinnamomum zeylanicum Breym (canela) e Zingiber officinalis Rox (gengibre), quitosana 1 e 3%, fungicida Procloraz a 100 µg.mL-1 e testemunha (sem tratamento). Para a avaliação da germinação de conídios, foram considerados seis tratamentos com cinco repetições. Foram utilizados os mesmos tratamentos, porém, nas concentrações de 7,5% de cada extrato (cravo-da-índia, canela e gengibre), 1,5% de quitosana, e 50 µg.mL-1 de Procloraz. Para o experimento in vivo, foram utilizados mamões “Formosa” “Tainung 1”, em delineamento inteiramente casualizado, sendo seis tratamentos com quatro repetições para avaliação de severidade de antracnose causada por Colletotrichum gloeosporioides. Os frutos foram tratados por imersão durante 5 minutos com extratos de cravo-da-índia, canela e gengibre a 15%, quitosana a 8% e testemunha com água destilada, e imersão por 2 minutos em fungicida Procloraz (33,75 g i.a./100 L). Os tratamentos com extrato de cravo-da-índia a 15% e quitosana a 8% foram eficazes em todas as avaliações, sendo uma alternativa viável ao fungicida Procloraz. Os tratamentos com extrato de gengibre foram menos eficientes, com controle intermediário para o extrato de canela.

ABSTRACT: We evaluated the efficacy of natural products in the control of papaya anthracnose, in vitro and in vivo. The in vitro experiments for evaluation of mycelial growth used a completely randomized 10 × 4 factorial design (treatments × evaluation periods) with eight replicates, with sporulation evaluated at the end of the experiment. The treatments involved the use of aqueous extract at concentrations of 5 and 15% for Syzygium aromaticum (L.) Merr. & Perry (clove), Cinnamomum zeylanicum Breym (cinnamon), and Zingiber officinalis Rox. (ginger); 1 and 3% chitosan; the fungicide Prochloraz at 100 µg.mL-1; and a control (no treatment). For evaluating conidia germination, we used six treatments with five replicates. The treatments included 7.5% of each extract (clove, cinnamon, and ginger), 1.5% chitosan, and 50 µg.mL-1 of Prochloraz. For the in vivo experiment, “Formosa” papaya “Tainung 1” was used in a completely randomized design, with six treatments and four replicates to evaluate the severity of anthracnose caused by Colletotrichum gloeosporioides. The fruits were treated by immersion for 5 min with 15% clove, cinnamon, and ginger extracts, 8% chitosan, and control with distilled water, and immersion for 2 min in Prochloraz (33.75 g a.i./100 L). The treatments with 15% clove extract and 8% chitosan were effective in all evaluations, resulting in a viable alternative to the fungicide Prochloraz. The treatments with ginger extract were less effective and those with cinnamon offered intermediate control.

Este trabalho relata uma ocorrência de Meloidogyne enterolobii (sin. M. mayaguensis) no Estado do Mato Grosso do Sul, parasitando goiabeira (Psidium guajava), cv. Novo Milênio. O nematoide foi caracterizado e identificado pelo fenótipo da isoenzima esterase (Est) (Est M2, Rm: 0,7 e 0,9).

This paper reports an occurrence of Meloidogyne enterolobii (syn. M. mayaguensis) in the State of Mato Grosso do Sul, on guava (Psidium guajava), cv. Novo Milênio. The nematode was characterized and identified using esterase (Est) isozyme phenotype (Est M2, Rm: 0.7 e 0.9).