Gilmar Paulo Henz

Doenças da mandioquinha-salsa e sua situação atual no Brasil

The diseases of arracacha that have already been recorded are described and their current situation in Brazil is discussed. Since its introduction in 1900-1910, arracacha has been considered a non-demanding crop, presenting some minor disease problems, especially when compared to other vegetable crops. Many of the recorded arracacha diseases in Brazil and other Latin American countries are poorly described, for there is hardly any information about pathogenicity tests, pathogen identity, crop losses and environmental conditions affecting diseases. Worldwide, 27 genera of fungi, three of bacteria, nine of nematodes and five species of viruses have been recorded. Of these, thirteen fungi and all bacteria and nematodes were recorded in Brazil. So far, no virus has been recorded, although virus-like symptoms have been observed. The most important diseases are the root knot, caused by Meloidogyne spp., and the postharvest soft rot caused by Erwinia spp. Commonly occurring diseases are leaf spots caused by Septoria spp., Cercospora spp. and Xanthomonas campestris pv. arracaciae, as well as plant rots caused by Sclerotium rolfsii and Sclerotinia sclerotiorum. Viruses could become of great importance since this crop is vegetatively propagated, and part of the plantlets are now being produced in nurseries by a new technique (pre-rooting) and then disseminated to different areas throughout Brazil. As there is no pesticide officially registered for this crop in Brazil, preventive measures of control must be used, such as crop rotation, suitable fertilization and irrigation, and removal and destruction of diseased plants. Arracacha seems to be suitable for organic cropping systems, since few diseases are considered limitant.

Murcha do manjericão (Ocimum basilicum) no Brasil: agente causal, círculo de plantas hospedeiras e transmissão via semente

Sweet basil (Ocimum basilicum L) is one of the most important vegetable crops in the family Lamiaceae, being employed mainly as a source of essential oils for the pharmaceutical industry. Samples of plants showing symptoms of wilt, stem blight and collar root rot were collected during the 2005 hot rainy season in the rural area of Brazlândia (Federal District) in central Brazil. Two other samples displaying identical symptoms were collected under greenhouse and field conditions in Ponte Alta (DF). The fungus Fusarium oxysporum was consistently isolated in all samples. Pathogenicity tests were conducted using seedlings and stem cuttings of the O. basilicum cultivars ‘Dark Opal’ and ‘Italian Large Leaf’ as well as accessions of the species O. americanum L, O. campechianum Mill., Origanum manjorana L., O. vulgare L., Mentha arvensis L., Coleus blumei Benth., Leonorus sibiricus L. and Leonotis nepetaefolia (L.) W.T. Aiton. All isolates were highly virulent on O. Reis, A.; Miranda, B.E.C.; Boiteux, L.S.; Henz G.P. Sweet basil (Ocimum basilicum) wilt in Brazil: Causal agent, host range and seed transmission. Summa Phytopathologica, v.33, n.2, p.137-141, 2007.

New cucurbitaceous hosts of Myrothecium roridum in Amazonas State, Brazil.

Myrothecium roridum e um fungo de solo parasita obrigatorio com um grande numero de hospedeiras. Entretanto, sua importância como patogeno de hortalicas, em particular cucurbitaceas, cultivadas no tropico umido, como a da Amazonia brasileira, ainda nao foi determinada. Foram analisadas sete amostras de plantas doentes de abobora, pepino e maxixe com manchas foliares oriundas dos municipios de Rio Preto, Iranduba e Silves, estado do Amazonas. Destas amostras, cinco isolados foram identificados como Myrothecium roridum, apresentando comprimento de fialides variando de 10,3 a 11,2 µm e tamanho de conidios 6,4-7 x 1.7-2,3 µm. Estes isolados foram inoculados em folhas, com e sem ferimentos, de maxixe, pepino, abobora, moranga, melancia e melao. Todos os isolados completaram os Postulados de Koch, constatando-se variabilidade em sua agressividade. Este e o primeiro registro de M. roridum causando manchas foliares em abobora(Cucurbita moschata), maxixe (Cucumis anguria) e pepino (C. sativus) no Brasil.

Incidência de injúrias mecânicas em raízes de mandioquinha-salsa na cadeia de pós-colheita

Size and appearance are the most important quality characteristics of arracacha roots. The aim of this experiment was to determine the main types and the incidence of mechanical injuries in arracacha roots and evaluate its incidence at the different stages of the postharvest handling system used in Brazil. Evalution was carried out during five steps of the postharvest handling system (after harvest; packinghouse, before and after washing; wholesale and retail markets) were verified. At each step, 110 roots were taken at random in ten samples (replications) at different places during March 2000 to June 2001. Four main types of mechanical damage were identified in arracacha roots: abrasion; partial rupture; splitting; and break. Superficial lesions caused by abrasion were the predominant mechanical injury and showed great variation, so an abrasion rating scale (1=no lesion; 5=>40% of lesions) was used. Increasing levels of abrasion were recorded as the arracacha roots flowed through the postharvest chain, reaching 13.3% of the roots at the farm; 19.7% before washing and 24.9% after washing at the packinghouse; 47.2% at the wholesale market; and 78.9% at the retail market. The incidence of other types of mechanical damage was higher at the wholesale market (7.6% of rupture, 4.2% of spliting, 10.6% of broken roots). The critical point for the incidence of mechanical damage at the postharvest chain occurred between the packinghouse and the wholesale market, probably due to inadequate packing in wooden boxes and rough handling.

Formas de apresentação e embalagens de mandioquinha-salsa no varejo brasileiro

In Brazil, arracacha is usually commercialized in open, non-refrigerated stands at the retail market, and consumers select and pick up the roots themselves. Recently the arracacha market underwent significant changes and new forms and product types were identified. The objective of this paper is to make a survey of arracacha packing and types of product commercialized at the Brazilian retail market, and a preliminary study of the consumer perception of the product in Sao Paulo. Data were collected through visits to supermarkets, grocery shops and other retail markets in the metropolitan areas of Sao Paulo and Brasilia from 2001 to 2003. Arracacha is sold at the retail market in ten distinct forms and product types, three of them organic and seven grown in the conventional system. The two most common ways of selling arracacha is displaying the roots on open market stands without wrapping and in Styrofoam trays wrapped with PVC films. Organic arracacha had higher average retail prices when compared to the traditional product, reaching R

Danos causados pelo impacto de queda na qualidade pós-colheita de raízes de mandioquinha-salsa

5.80/kg for non-packed roots, R

A Novel Postharvest Rot of Okra Pods Caused by Rhizoctonia solani in Brazil

9.95/kg for PVC-wrapped roots and R

Food losses and waste: how Brazil is facing this global challenge?

11.54/kg for precooked and vacuum-packed roots. For the conventionally cultivated arracacha, prepacked forms (PVC film), minimally processed roots (peeled; slices; rods; whole roots packed in vacuum-sealed bags) and precooked roots in vacuum-sealed bags had higher prices at the retail market, ranging from R

Desafios enfrentados por agricultores familiares na produção de morango no Distrito Federal

4.16/kg (peeled roots) to R

'BRS Mari': new hot pepper cultivar for processing

8.60/kg (slices). The new arracacha forms and product types at the Brazilian retail market had higher added value and fulfill specific market demands.