Protein feeding of Queensland fruit fly Bactrocera tryoni and cucumber fly Zeugodacus cucumis (Diptera: Tephritidae) on non-host vegetation: effect of plant species and bait height

Perimeter-baiting of non-crop vegetation using toxic protein baits was developed overseas as a technique for control of melon fly, Zeugodacus (Zeugodacus) cucurbitae (Coquillett) (formerly Bactrocera (Zeugodacus) cucurbitae), and evidence suggests that this technique may also be effective in Australia for control of local fruit fly species in vegetable crops. Using field cage trials and laboratory reared flies, primary data were generated to support this approach by testing fruit flies' feeding response to protein when applied to eight plant species (forage sorghum, grain sorghum, sweet corn, sugarcane, eggplant, cassava, lilly pilly and orange jessamine) and applied at three heights (1, 1.5 and 2 m). When compared across the plants, Queensland fruit fly, Bactrocera tryoni (Froggatt), most commonly fed on protein bait applied to sugarcane and cassava, whereas more cucumber fly, Zeugodacus (Austrodacus) cucumis (French) (formerly Bactrocera (Austrodacus) cucumis), fed on bait applied to sweet corn and forage sorghum. When protein bait was applied at different heights, B. tryoni responded most to bait placed in the upper part of the plants (2 m), whereas Z. cucumis preferred bait placed lower on the plants (1 and 1.5 m). These results have implications for optimal placement of protein bait for best practice control of fruit flies in vegetable crops and suggest that the two species exhibit different foraging behaviours.

Soybean Stem Fly, Melanagromyza sojae (Diptera: Agromyzidae), in the New World: detection of high genetic diversity from soybean fields in Brazil

Soybean Stem Fly (SSF), Melanagromyza sojae (Zehntner), belongs to the family Agromyzidae and is highly polyphagous, attacking many plant species of the family Fabaceae, including soybean and other beans. SSF is regarded as one of the most important pests in soybean fields of Asia (e.g., China, India), North East Africa (e.g., Egypt), parts of Russia, and South East Asia. Despite reports of Agromyzidae flies infesting soybean fields in Rio Grande do Sul State (Brazil) in 1983 and 2009 and periodic interceptions of SSF since the 1940s by the USA quarantine authorities, SSF has not been officially reported to have successfully established in the North and South Americas. In South America, M. sojae was recently confirmed using morphology and its complete mitochondrial DNA (mtDNA) was characterized. In the present study, we surveyed the genetic diversity of M. sojae, collected directly from soybean host plants, using partial mtDNA cytochrome oxidase I (COI) gene, and provide evidence of multiple (>10) maternal lineages in SSF populations in South America, potentially representing multiple incursion events. However, a single incursion involving multiple-female founders could not be ruled out. We identified a haplotype that was common in the fields of two Brazilian states and the individuals collected from Australia in 2013. The implications of SSF incursions in southern Brazil are discussed in relation to the current soybean agricultural practices, highlighting an urgent need for better understanding of SSF population movements in the New World, which is necessary for developing effective management options for this significant soybean pest. © FUNPEC-RP.

Resistance to phosphine in Sitophilus oryzae in Australia: A national analysis of trends and frequencies over time and geographical spread

In Australia, along with many other parts of the world, fumigation with phosphine is a vital component in controlling stored grain insect pests. However, resistance is a factor that may limit the continued efficacy of this fumigant. While strong resistance to phosphine has been identified and characterised, very little information is available on the causes of its development and spread. Data obtained from a unique national resistance monitoring and management program were analysed, using Bayesian hurdle modelling, to determine which factors may be responsible. Fumigation in unsealed storages, combined with a high frequency of weak resistance, were found to be the main criteria that led to the development of strong resistance in Sitophilus oryzae. Independent development, rather than gene flow via migration, appears to be primarily responsible for the geographic incidence of strong resistance to phosphine in S. oryzae. This information can now be utilised to direct resources and education into those areas at high risk and to refine phosphine resistance management strategies.

Research into crown rot and wilt diseases of strawberries in Queensland

Plant losses due to fungal diseases in strawberry (Fragaria × ananassa Duch.) can potentially cause total loss of production. Three fungal pathogens, Fusarium oxysporum f. sp. fragariae, Colletotrichum gloeosporioides and Macrophomina phaseolina, cause similar crown rot and wilt symptoms in strawberries in Queensland. Since the withdrawal of methyl bromide in 2005, no effective chemical control of any of the three pathogens has been available. This study aims at identifying sources of plant genetic resistance that can be used in the breeding program to develop resistant cultivars for use as part of an integrated disease management plan in commercial strawberry production. Results from glasshouse pathogenicity and screening trials on the three pathogens showed that when breeding for resistance against a pathogen, resistance to other pathogens also needs to be considered, e.g., cultivar 'Festival' is resistant to F. oxysporum f. sp. fragariae, but is highly susceptible to C. gloeosporioides. The cultivars 'Earlisweet', 'Kabarla' and 'Phenomenal', two seedling clones and four DAFF breeding lines were resistant to C. gloeosporioides. Cultivar 'Suncoast Delight' showed the most promising level of resistance to M. phaseolina. These cultivars, breeding lines and seedling selections have been made available for incorporation into the crossing program to support the Queensland strawberry breeding program.

Investigation into various fungicides and alternative solutions for controlling postharvest diseases in papaya fruit

In Australia, Sportak® (a.i., prochloraz) has been registered since the early 1980's for the postharvest control of both anthracnose and stem-end rots in papaya fruit, despite the persistence of fruit breakdown due to disease during transit and at market destinations. Consequently, the Australian papaya industry has been concerned over the efficacy of prochloraz and whether substitute or alternative solutions were available for better disease control, particularly during times of peak disease pressure. This study therefore investigated the effects of various postharvest treatments for disease control in papaya. Fruit were harvested at colour break from coastal farms in Far North Queensland and treated with commercial rates of various fungicides, including prochloraz, imazalil, thiabendazole and fludioxonil. Additional solutions known to inhibit disease were examined, including chitosan and carnauba wax both with and without ammonium carbonate (AC). Following treatment, fruit were ripened and assessed for quality over their shelf life. Fludioxonil when applied as a hot dip was found to be a more efficacious treatment for control of disease in papaya than prochloraz. The other fungicides were moderately effective, as both thiabendazol and prochloraz exhibited an intermediate response and imazalil was the least effective. Disease severity was lowest in fruit treated with AC followed by chitosan, whilst chitosan delayed degreening. Overall, the study found that hot fludioxonil provided an effective replacement of the currently registered chemical prochloraz, and that alternate solutions such chitosan and AC may also be beneficial, particularly for low chemical input farming systems.

Effect of diet on phosphine toxicity, rate of development and reproduction of the rice weevil Sitophilus oryzae (Linnaeus)

One of the loci responsible for strong phosphine resistance encodes dihydrolipoamide dehydrogenase (DLD). The strong co-incidence of enzyme complexes that contain DLD, and enzymes that require thiamine as a cofactor, motivated us to test whether the thiamine deficiency of polished white rice could influence the efficacy of phosphine fumigation against insect pests of stored grain. Three strains of Sitophilus oryzae (susceptible, weak and strong resistance) were cultured on white rice (thiamine deficient), brown rice or whole wheat. As thiamine is an essential nutrient, we firstly evaluated the effect of white rice on developmental rate and fecundity and found that both were detrimentally affected by this diet. The mean time to reach adult stage for the three strains ranged from 40 to 43 days on brown rice and 50–52 days on white rice. The mean number of offspring for the three strains ranged from 7.7 to 10.3 per female over a three day period on brown rice and 2.1 to 2.6 on white rice. Growth and reproduction on wheat was similar to that on brown rice except that the strongly resistant strain showed a tendency toward reduced fecundity on wheat. The susceptible strain exhibited a modest increase in tolerance to phosphine on white rice as expected if thiamine deficiency could mimic the effect of the dld resistance mutation at the rph2 locus. The strongly resistant strain did not respond to thiamine deficiency, but this was expected as these insects are already strongly resistant. We failed, however, to observe the expected synergistic increase in resistance due to combining thiamine deficiency with the weakly resistant strain. The lack of interaction between thiamine content of the diet and the resistance genotype in determining the phosphine resistance phenotype suggests that the mode of inhibition of the complexes is a critical determinant of resistance.

Does fumigation of durum wheat and semolina with sulfuryl fluoride affect quality of the grain, semolina, and derived spaghetti and bread?

There is no information on the effect of sulfuryl fluoride (SF) on durum wheat technological properties and products made from fumigated durum wheat. Durum wheat and semolina were exposed to a range of SF applications under conditions that might be typically encountered in bulk storage facilities used in many countries. SF greatly reduced the germination percentage of fumigated durum wheat, with increasing impact under higher SF concentration, grain moisture content, and fumigation temperature. SF greatly reduced seed germination percentage, impacting more the higher the SF concentration. SF had little to no effect on grain test weight, 1,000-grain weight, hardness, protein content, semolina ash content, and mixograph properties. At the highest SF concentration (31.25 mg/L for 48 h) there was a tendency for pasta cooking loss to be increased but still acceptable, and other pasta properties were largely unaffected. Fumigation with SF did not have any impact on the baking properties of a wholemeal durum flour-commercial flour mix. Therefore, SF is not recommended if the grains are to be used as seeds for agricultural production, but for the production of semolina, pasta, and bread, SF used under typical fumigation conditions has little to no impact on technological properties of durum wheat. © 2016 AACC International, Inc.

Avaliação da toxicidade aguda do inseticida metomil e o seu efeito sobre a atividade da acetilcolinesterase do peixe Danio rerio

Methomyl (Lannate®) is an insecticide from the carbamate group, frequently used in pest control in various types of crops. This compound works inhibiting the activity of the enzyme acetylcholinesterase. The use of physicochemical and ecotoxicological analysis is the most efficient strategy for the correct characterization and control of residues of metomil. The main objectives of this study were to evaluate the acute toxicity of methomyl in 96 hours of exposure and, through a sublethal assay of 5 hours, to assess its effect on the activity of acetylcholinesterase present in brain and squeletic dorsal muscle of the Danio rerio fish. The results showed that the LC50-96 found to D. rerio was 3.4 mg/L and it was found through the average of four definitive tests. In vitro assays were used to test the inhibitory action of methomyl directly over soluble AChE, extracted from the squeletic dorsal muscle, with maximum inhibition of 68.57% to the insecticide concentrations of 0.2 mg/L. In sublethal tests with D. rerio, inhibitory effect of methomyl was found over the soluble form of AChE in the squeletic dorsal muscle, both in one and five hours of fish exposure to the insecticide. In both period, the average values of inhibition were around 61%. In the same condition, no significant inhibitory effect of methomyl soluble and membrane AChE of the D. rerio was observed in the 0.42, 0.85, 1.70 and 2.50 mg/L concentrations and in both times of fish exposure

Enhancing legume ecosystem services through an understanding of plant–pollinator interplay

Legumes are bee-pollinated, but to a different extent. The importance of the plant– pollinator interplay (PPI), in flowering crops such as legumes lies in a combination of the importance of pollination for the production service and breeding strategies, plus the increasing urgency in mitigating the decline of pollinators through the development and implementation of conservation measures. To realize the full potential of the PPI, a multidisciplinary approach is required. This article assembles an international team of genebank managers, geneticists, plant breeders, experts on environmental governance and agro-ecology, and comprises several sections. The contributions in these sections outline both the state of the art of knowledge in the field and the novel aspects under development, and encompass a range of reviews, opinions and perspectives. The first three sections explore the role of PPI in legume breeding strategies. PPI based approaches to crop improvement can make it possible to adapt and re-design breeding strategies to meet both goals of: (1) optimal productivity, based on an efficient use of pollinators, and (2) biodiversity conservation. The next section deals with entomological aspects and focuses on the protection of the “pest control service” and pollinators in legume crops. The final section addresses general approaches to encourage the synergybetweenfoodproductionandpollinationservicesatfarmerfieldlevel.Twobasic approaches are proposed: (a) Farming with Alternative Pollinators and (b) Crop Design System.

Enhancing legume ecosystem services through an understanding of plant–pollinator interplay

Legumes are bee-pollinated, but to a different extent. The importance of the plant– pollinator interplay (PPI), in flowering crops such as legumes lies in a combination of the importance of pollination for the production service and breeding strategies, plus the increasing urgency in mitigating the decline of pollinators through the development and implementation of conservation measures. To realize the full potential of the PPI, a multidisciplinary approach is required. This article assembles an international team of genebank managers, geneticists, plant breeders, experts on environmental governance and agro-ecology, and comprises several sections. The contributions in these sections outline both the state of the art of knowledge in the field and the novel aspects under development, and encompass a range of reviews, opinions and perspectives. The first three sections explore the role of PPI in legume breeding strategies. PPI based approaches to crop improvement can make it possible to adapt and re-design breeding strategies to meet both goals of: (1) optimal productivity, based on an efficient use of pollinators, and (2) biodiversity conservation. The next section deals with entomological aspects and focuses on the protection of the “pest control service” and pollinators in legume crops. The final section addresses general approaches to encourage the synergybetweenfoodproductionandpollinationservicesatfarmerfieldlevel.Twobasic approaches are proposed: (a) Farming with Alternative Pollinators and (b) Crop Design System.

Biotechnology and crop protection in Brazil.

The process of modernization of Brazilian agriculture aimed at increasing the productivity in response to the high demand for agricultural products in the world market and it was based on the intensive use of inputs such as agrochemicals, intense mechanisation and breeding of new varieties. Among these, pesticides were incorporated in almost all production systems. Over reliance on pesticide use has produced many negative effects on both biotic and abiotic components of the environment, generating chemical contamination of soil and water, decrease in biological diversity of agroecosystems, disruption of natural cycles, pest resistance, intoxication of growers, among others. The consumption of pesticides in Brazil was 151.8 thousand tonnes in 1989, and today the country is the fifth world market of these products. The use of pesticides increased from 16 thousand tonnes (a.i.) in 1964 to 60.2 thousand tonnes in 1991, while the area planted to crops grew from 28.4 to 50.0 million ha in the same period. This means an increase of 276.2% in consumption of pesticides compared to an increase of 76% in planted area. Even with this large increase in the use of pesticides, the losses caused by pests have not been significantly reduced, and the net gain in crop productivity has been low. On the other hand, problems with food contamination, environmental degradation of growers have considerably mounted. It is possible to define two classes of crops regarding intense use of pesticides. One is represented by those crops that occupy large areas, and therefore contribute to a large amont of pesticides used for pest control in a country basis. The other class comprises crops that require large amounts of pesticides per unit of area, but not necessarily represent large amounts of pesticides used coutry-wide. Based on the classes proposed, citrus, soybean and sugarcane stand as crops with a nationally great consumption of pesticides, while tomato, potato and citrus are important as intensive users of pesticides. In this paper the biotechnologies in use, the biotechnologies in advanced stages of development, the main constraints to the development and use of biotechnlology and the impact of pesticed on the environment are discussed.

Formigas associadas a cochonilhas-farinhentas em cultivos de videira no semiárido brasileiro.

A região do Submédio São Francisco é pioneira na produção de uvas em condições tropicais no Brasil. No entanto, com a expansão das áreas cultivadas, surge simultaneamente, a ampliação da distribuição de insetos-praga (OLIVEIRA et al., 2010), como as cochonilhas. Dentre as espécies que atacam os cultivos de videira na região, destacam-se as cochonilhas-farinhentas (Hemiptera: Pseudococcidae) das espécies Maconelicoccus hirsutus (Green, 1908), Planococcus citri (Risso, 1813) e Dysmicoccus brevipes (Cockerell, 1893). Estas espécies podem ocasionar danos em uvas destinadas ao consumo in natura, danificando as bagas devido à sucção de seiva e como consequência, favorecer o aparecimento da fumagina, depreciando a fruta para o mercado externo e o interno (MORANDI FILHO, 2008). As formigas são muito importantes por dispersarem as cochonilhas-farinhentas e a constatação de algumas espécies em videira pode ser um indicativo da presença de populações destes insetos (DAANE et. al., 2006). Formigas e cochonilhas da família Pseudococcidade podem associar-se com benefícios mútuos. Neste tipo de relação, as formigas se alimentam do honeydew excretado e em troca, defendem as cochonilhas dos seus inimigos naturais, diminuem a taxa de mortalidade, e consequentemente, aumentam a população de cochonilhas, auxiliam na diminuição da contaminação dos fungos e/ou transportam as suas ninfas para outros locais de nidificação (ZHOU et al., 2015). Um exemplo é a espécie de formiga argentina Linepithema humile (Hymenoptera: formicidae) que tem se associado diretamente à cochonilha-farinhenta em busca das excreções açucaradas, tendo sido considerada uma das principais pragas, como na Califórnia e na África do Sul (DAANE et al. 2006). Além disso, a presença de formigas dificulta o controle biológico (MGOCHEKI; ADDISON, 2009) e como as formigas transportam as ninfas para o interior dos cachos, o controle é dificultado. Assim, o controle de formigas deve estar associado às estratégias de manejo das cochonilhas-praga (DAANE et. al., 2008). Com isso, o objetivo deste trabalho foi realizar o levantamento de espécies de formigas 31 doceiras associadas à cochonilhas-farinhentas (Hemiptera: Pseudococcidae) em cultivos de videira no Submédio São Francisco.

Cochonilha rosada Maconelicoccus hirsutus: inter-relações no ambiente produtivo de videira e plantas espontâneas.

Maconellicoccus hirsutus (Green, 1908) (Hemiptera: Pseudococcidae), conhecida como cochonilha-rosada-do-hibisco é uma espécie altamente polífaga por apresentar hospedeiros distribuídos em 76 famílias, incluídos em mais de 200 gêneros, (OEPP/EPPO, 2005), podendo causar severos danos em culturas economicamente importantes como algodão, citros, cacau, café e uva (TAMBASCO et al., 2000). Esta cochonilha foi registrada pela primeira vez no Brasil em 2010 no Estado de Roraima infestando mudas de hibisco (MARSARO JÚNIOR et al., 2013) e no ano de 2012 foi encontrada no Estado do Espírito Santo em cultivo de quiabo (CULIK et al., 2013). Em 2013, no Espírito Santo e na Bahia, foi registrada a ocorrência da cochonilha rosada em cacaueiros (CEPLAC, 2014). Neste mesmo ano, M. hirsutus foi excluída da lista de pragas quarentenárias ausentes A1. E recentemente, foi registrada na região do Submédio do Vale do São Francisco em cultivos de videira (OLIVEIRA et. al., 2014). O Submédio do Vale do São Francisco é responsável por 95% das exportações brasileiras de uvas de mesa e infestações de cochonilhas vem sendo constatadas com frequência em parreiras comerciais. As cochonilhas são encontradas alimentando-se em todas as partes da planta de uva, sendo frequentemente observados sérios prejuízos a produção. As cochonilhas possuem vários hospedeiros alternativos que mantêm a população na entressafra, permitindo rápida infestação e crescimento populacional. Como recentemente M. hirsutus foi relatada se dispersando rapidamente pelo Brasil e constatada recentemente na região, o conhecimento de plantas hospedeiras alternativas torna-se uma prática importante, visto que, muitas plantas podem ser hospedeiras de cochonilhas durante o período em que a planta não está produzindo e, além disso, é um dos requisitos fundamentais para o planejamento do manejo integrado (MAZIERO et. al., 2007). Assim, este trabalho teve como objetivo identificar as espécies de plantas hospedeiras alternativas de M. hirsutus em agroecossistemas de videira na região do Submédio do Vale do São Francisco.