Meloidogyne paranaensis is one of the most destructive root-knot nematode (RKN) species parasitizing coffee in Brazil and in the Americas generally. The objectives of this study were to assess the genetic variability, aggressiveness and virulence of seven different M. paranaensis populations on susceptible and resistant Coffea spp. All seven RKN populations were identified by biochemical and molecular methods. Coffee seedlings were inoculated in the greenhouse, and the nematode reproduction factor was used to infer their reproduction on coffee genotypes. Phylogenetic studies showed a low genetic variability in M. paranaensis populations, regardless of the existence of three esterase phenotypes (Est P1, P2 and P2a), except for the population Est P2a from Guatemala, which is genetically different from other M. paranaensis populations from Brazil. The Est P2a and Est P2 (Herculândia, SP, Brazil) populations were the most aggressive on two susceptible C. arabica cultivars under greenhouse conditions. None of the M. paranaensis populations were virulent on resistant coffee genotypes, confirming their resistance to the seven M. paranaensis populations tested. The resistant coffee cultivars, namely Clone 14 INCAPER, Catua ı Vermelho 9 Amphillo MR2161 (E1 16-5 III), Apoatã IAC 2258, Timor Hybrid UFV 408-01 (E1 6-6 II) and IPR 100, exhibited segregation for resistance in the ratio of 0%, 2.4%, 12%, 26% and 29%, respectively. These are promising results, because they validate resistance against several M. paranaensis populations in different Coffea spp. genetic resources, which can be used in breeding programmes or as rootstocks, such as Apoatã IAC 2258 and Clone 14 INCAPER.

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horticultura horticultura brasileira brasileira O cultivo do pimentão (Capsicum annuum) em estufa tem aumentado consideravelmente nos últimos anos devido às altas produtividades e rentabilidade da cultura. Entretanto, o cultivo intensivo neste sistema tem acarretado graves problemas, destacando-se a maior ocorrência de doenças devido à limitação de rotação de culturas. Nestas condições, patógenos habitantes de solo são favorecidos e se estabelecem na área após cultivos sucessivos de materiais suscetíveis, como é o caso dos nematoides-das-galhas, especialmente Meloidogyne incognita e M. javanica, que são mais parasitos das hortaliças. ABSTRACT Reaction of Capsicum genotypes to root-knot nematodeThe objective of this research was to evaluate the response of experimental hybrids of Capsicum annuum ['Experimental Hybrid (EH)' and its Reciprocal (EHR)] and Embrapa Hortaliças elite genotypes of C. chinense, C. frutescens and C. baccatum to Meloidogyne incognita race 1, M. javanica and M. enterolobii. The hybrid pepper 'Magali R' was used as susceptible control to M. incognita race 1 and resistant to M. javanica, and as resistant controls to M. incognita race 1 and M. javanica 'Silver' and 'Snooker' rootstocks were used. 'Rutgers' tomato was used to confirm the viability of the inoculum. Two experiments were carried out in a greenhouse in a completely randomized design with six replications. Thirty-day old seedlings were transplanted to 2.0 L pots containing a mixture of soil, sand, cattle manure and carbonized rice husk (1:1:1:1). Plants were inoculated after transplanting with deposition of 5.0 mL of suspension containing 5,000 eggs and J2 of each species alone. After seventy days, plants were assessed by measuring the index of egg mass and galls, the number of eggs per gram of roots and the reproduction factor. The C. annuum experimental rootstock hybrids were resistant to M. incognita and M. javanica and susceptible to M. enterolobii, similar to 'Silver' and 'Snooker'. The hybrid 'Magali R' only showed resistance to M. javanica. Elite genotypes of C. chinense and C. baccatum were susceptible to all three species, while genotypes of C. frutescens were susceptible only to M. enterolobii. The experimental hybrids of Capsicum annuum and most genotypes of C. frutescens may be used in protected cultivation areas infested with M. incognita race 1 and M. javanica. However the search for resistant genotypes to M. enterolobii, as well as the development and adoption of control strategies is of crucial importance.

A questão de perdas após a colheita vem sendo estudada de forma não sistemática por diferentes especialistas e instituições, em diferentes fases da cadeia de comercialização e para produtos ou grupos de produtos, nos quais estejam primordialmente interessados (Rezende, 1992).As principais causas apontadas para as perdas de cenoura foram podridão por Erwinia, nematóides, distúrbios fisioló-gicos (Mukai & Kimura, 1986) época, deficiência nos tratamentos de lavagem e secagem, embalagem, manuseio e transporte inadequados, danos mecânicos, tempo de exposição prolongado no varejo, preços desfavoráveis pagos ao produtor e falta de orientação de mercado (Rezende, 1992).No levantamento realizado pela SUDENE (1972), os entrevistados atribuíram grau de importância às causas de perdas. No varejo, a demora entre compra e venda e a má qualidade do produto comprado foram apontados como principais causas, seguidas por embalagem inadequada e armazenamento inapropriado.A aplicação de questionários é uma metodologia subjetiva e os dados obtidos nem sempre correspondem à situação real ou permitem a identificação das causas primárias de perdas e a diferenciação entre causa e efeito. Contradições entre a informação fornecida pelos agentes de comercialização e a situação observada in loco foram apresentadas por SUDENE (1972), Ueno (1976) e Mukai RESUMOAs perdas pós-colheita de cenoura em 4 lojas de uma rede de supermercados de Brasília foram avaliadas pelo período de um ano. A amostragem foi realizada em duas etapas: antes da exposição do produto na área de vendas (amostra Qualidade Inicial) e após o descarte das perdas do produto (amostra Descarte). Foram quantificadas a proporção de raízes pequenas, médias e grandes e a incidência dos danos: bifurcação, rachadura, defeitos de formato, doença, praga, dano mecânico e outros. A cenoura comprada pelo supermercado apresentou cerca de 86,88 + 0,66% das raízes na faixa de 12-22 cm. No descarte, diminuiu a proporção de cenouras médias e grandes, enquanto aumentou a proporção de cenouras pequenas e quebradas. A proporção de raízes com ombro verde foi reduzida de 23,74 + 1,11% na amostra Qualidade Inicial para 13,29 + 1,37% na amostra Descarte, indicando que grande parte das raízes com ombro verde foi adquirida pelo consumidor, e neste caso não parece ter sido um fator indutor de perda. Cerca de 51% das cenouras recebidas no supermercado apresentavam algum tipo de dano, sendo os mais importantes defeitos de formato (31,0 + 1,16%), dano mecânico (9,46 + 0,4%) e murcha (4,66 + 0,99%). As principais causas de descarte foram dano mecânico (37,4 + 2,47%), defeitos de formato (32,0 + 2,58%) e murcha (7,6 + 1,59%). Palavras-chave:Daucus carota, amostra estratificada. ABSTRACT Identification of causes of postharvest carrot losses in the retail marketCarrot post-harvest losses were evaluated for one year in four stores of a supermarket chain in Brasilia, Brazil. Sampling was performed at two stages: at reception in the store and after exclusion or removal from retail displays. The proportion of large,...

The root-knot nematode Meloidogyne incognita is widely distributed and a major pathogen of cotton (Gossypium spp.) worldwide. The objectives of this study were to assess the genetic variability and aggressiveness of Brazilian populations of M. incognita in cotton. Five populations of M. incognita and one isolate of M. enterolobii (outgroup) were used in the molecular analysis. Our results showed that only 2.7 % of the RAPD and AFLP fragments were polymorphic. Despite the existence of two races (races 3 and 4) and two esterase phenotypes (I1 and I2), a low genetic variability among populations was observed, which might be due to the mitotic parthenogenetic mode of reproduction of this pathogen. The aggressiveness/virulence among populations towards different cotton genotypes was also studied. None of the populations was virulent to the resistant cotton genotypes M-315 RNR, TX-25, CIR1343, Wild Mexican Jack Jones and CIR1348 (reproduction factor <1). Two populations of M. incognita from the states of Mato Grosso do Sul and Parana (Umuarama) (races 4 and 3, respectively) were highly aggressive to the susceptible control FM966 and virulent to the accessions LA-887 and Clevewilt-6 that showed moderate resistance to other populations tested.

The reaction of seven genotypes of Coffea arabica to 10 Meloidogyne spp. populations collected mainly from coffee plantations in Brazil and Costa Rica was evaluated under greenhouse conditions. The inoculum consisted of 10,000 eggs per plant. Evaluations were done 8 months after inoculations considering the root fresh weight, gall and egg mass indices, number of eggs per gram of root and reproduction factor (RF). The cultivars Obatã IAC 1669-20, Sarchimor IAC 4361 and Tupi Amarelo IAC 5111 exhibited susceptibility to the four Brazilian M. exigua populations tested. However, cv. Tupi Vermelho IAC 1669-33 revealed resistance (RF value of 0.7) to the M. exigua population from Lavras, Minas Gerais State, Brazil. A population of M. exigua from Bom Jesus de Itabapoana, Rio de Janeiro State, Brazil, was highly virulent on cv. IAPAR 59 (RF= 165.7), bearing resistance gene Mex-1, and was also virulent on genotype Paraíso (H 419-5-4-5-2) (RF=396.2). A Meloidogyne sp. population on coffee from Garça, São Paulo State, Brazil, reproduced at low rates (RF ranging from 0.1 to 3.9) on all genotypes. All tested cultivars were susceptible to M. incognita and M. paranaensis. M. mayaguensis of guava from Paraná State, Brazil, reproduced at low rates in all coffee genotypes; however, another population of coffee, from Costa Rica, was more aggressive and showed RF value that ranged from 0.8 to 12.4. Results of this study point for the first time to the ability of a naturally occurring M. exigua population to overcome the resistance conferred by the Mex-1 gene.

The present work aimed to evaluate the behavior of ten fertility attributes of soil organic matter physical fractions and total organic carbon upon addition of three EM Bokashis to a Rhodic Ferralsol (FRr) and a Dystric Cambisol (CMd). An experiment was carried out in greenhouse in which the soils were placed into plastic trays and cultivated with tomato. A completely randomized design was used with four repetitions and factorial scheme of 2 × 3 + 2, consisting of two soils (FRr and CMd), three EM Bokashis (Poultry Manure Bokashi (BPM); CNPH Bokashi (BC); and Cattle Manure Bokashi (BCM)), and two controls (both soils without addition of Bokashi). The following fertility attributes were evaluated: pH, Ca 2+ , Mg 2+ , K + , Na + , P, SB, H + Al, CEC, and . Particulate organic carbon (POC) and mineral-associated organic carbon (MOC) and total organic carbon (TOC) were also investigated. Finally, the Principal Component Analysis was conducted in order to identify possible patterns related to soils when fertilized with EM Bokashi. The addition of EM Bokashi increased the soil fertility and contents of POC. Different EM Bokashi presents distinguished effects on each soil. The PCA suggests that BPM presents higher capacity to modify the analyzed chemical attributes.

Field chemical control of bacterial spot on tomato for industrial processingIn order to evaluate chemical control of bacterial spot on tomato for industrial processing, two field trials were carried out at the Unilever Bestfoods experimental station, in Goiânia, Goias state, Brazil. The first trial was in a randomized complete block design, with 15 treatments and three replications, using the hybrid Heinz 9992 inoculated with Xanthomonas perforans. The second trial was in a split-plot randomized complete block design with chemical foliar applications (10 treatments) and hybrids (Hypeel 108 and U2006) as factors. Plants were inoculated with X. perforans and X. gardneri. In both trials the chemicals, in different number of applications and combinations, were: acibenzolar-S-methyl (ASM); famoxadone + mancozeb; metiram + pyraclostrobin; phosphite PK; benzalkonium chlorides; cuprous oxide, and copper hydroxide (SC, WP and WG). For both trials, disease severity on leaves, number of fruits with symptoms and yield were evaluated. In the second one, sunscald was also evaluated. For the first trial, significant severity differences (p>0.05) among treatments were observed only in the first two evaluations, but none of them differed from the water check control. In the second trial, significant differences were detected only in foliar severity in first evaluation for hybrids. For number of fruits with symptoms and sunscald, besides hybrids, interaction among factors was also significant. 'U2006' was more resistant than 'Hypeel 108', which also had highest sunscald values, but concerning fruits with symptoms, the opposite was observed. The two factors were significant for yield data, 'U2006' yielded better than 'Hypeel 108'. Despite none of the treatments have differed in yield from the water control, famoxadone + mancozeb, which resulted in the highest yield, differed from copper hydroxide, ASM -famoxadone + mancozeb, and benzalkonium chlorides. ASM and famoxadone + mancozeb were those that promoted benefit/cost relation higher than 1.