Aphids associated with shrubs, herbaceous plants and crops in the Maltese Archipelago (Hemiptera, Aphidoidea)

A survey of the aphids associated with Maltese shrubs, herbaceous plants and crops was carried out. Sixty six aphid species were recorded from more than 90 species of host plants. Forty eight aphids were recorded from the Maltese islands for the fi rst time bringing the total number of aphid species known from these islands to 99. New records include: Acyrthosiphon lactucae, A. pisum, Anoecia vagans, Aphis alienus, A. euphorbiae, A. hederae, A. lambersi, A. multifl orae, A. nasturtii, A. parietariae, A. picridicola, A. ruborum, A. sedi, Aulacorthum solani, Brachycaudus helichrysi, Capitophorus sp. nr. similis, Clypeoaphis suaedae, Cryptomyzus korschelti, Dysaphis apiifolia, D. foeniculus, D. pyri, D. tulipae, Hyadaphis coriandri, H. foeniculi, H. passerinii, Hyperomyzus lactucae, Idiopterus nephrelepidis, Macrosiphoniella absinthii, M. artemisiae, M. sanborni, Macrosiphum euphorbiae, Ma. rosae, Melanaphis donacis, Metopolophium dirhodum, Pterochloroides persicae, Rectinasus buxtoni, Rhopalosiphum maidis, R. padi, R. rufi abdominale, Schizaphis graminum, Semiaphis dauci, Sipha maydis, Sitobion avenae, S. fragariae, Therioaphis alatina, Uroleucon inulae, U. hypochoeridis and U. sonchi. Of these 99 aphid species, 58 are of economic importance and 16 are alien introductions. For 15 of the aphid species, a total of 22 new host-plant records are made. Ten species of ants were found attending 18 aphid species.peer-reviewe

A common phytoene synthase mutation underlies white petal varieties of the California poppy.

The California poppy (Eschscholzia californica) is renowned for its brilliant golden-orange flowers, though white petal variants have been described. By whole-transcriptome sequencing, we have discovered in multiple white petal varieties a single deletion leading to altered splicing and C-terminal truncation of phytoene synthase (PSY), a key enzyme in carotenoid biosynthesis. Our findings underscore the diverse roles of phytoene synthase in shaping horticultural traits, and resolve a longstanding mystery of the regaled golden poppy

“And it’s just when I think I’ve won the staring contest”: Viewing the World through Science and Poetry with Madhur Anand

In this interview, poet and ecologist Madhur Anand discusses her collection of poetry, A New Index for Predicting Catastrophes, with Alec Follett. She considers the poetic potential of scientific language as well as other topics related to her poetry and her research including field guides, biodiversity, and socio-ecological relationships

The application of low pressure storage to maintain the quality of zucchinis

Zucchini (Cucurbita pepo var. cylindrica) were stored at low pressure (4 kPa) at 10°C at 100% relative humidity for 11 days. Fruit quality was examined upon removal and after being transferred to normal atmosphere (101 kPa) at 20°C for three days. Zucchinis stored at low pressure exhibited a 50% reduction in stem-end browning compared with fruit stored at atmospheric pressure (101 kPa) at 10°C. The benefit of low pressure treatment was maintained after the additional three days storage at normal atmospheric pressure at 20°C. Indeed, low pressure treated fruit transferred to regular atmosphere 20°C for three days possessed a significantly lower incidence of postharvest rot compared to fruit stored at regular atmospheric pressure at 10°C. Zucchinis stored at low pressure showed higher levels of acceptability (28% and 36%, respectively) compared to fruit stored at regular atmospheres at 10°C for both assessment times.<br/

Evaluation of host resistance inducers and conventional products for fire blight management in loquat and quince

Fire blight disease is one of the most destructive diseases of pome fruits. Due to the lack of effective, non-phytotoxic and publicly acceptable materials for controlling fire blight in pome fruit trees, new strategies to manage Erwinia amylovora fire blight are being sought. The resistance-inducing compounds prohexadione-Ca, harpin protein and benzothiadiazole (acibenzolar-S-methyl), the fertilizer humic acid, the bactericides streptomycin and copper salts, and combinations of copper with chemicals were evaluated for their ability to control fire blight on quince and loquat cultivars. Prohexadione-Ca was applied at a rate of 125 mg L-1 at two shoot lengths (6-12 cm and 15-20 cm), while benzothiadiazole + metalaxyl (135 mg L-1) and harpin (50 mg L-1) were applied when the shoots measured between 15-20 cm, and again at 30-35 cm. On loquat cv. Cukurgobek, benzothiadiazole + metalaxyl showed about 60% effectiveness. The addition of copper salts reduced the effectiveness of benzothiadiazole + metalaxyl. On quince cultivars, streptomycin (P ≤ 0.05) was the most effective treatment during both years, followed by the harpin protein alone and in combination with copper salts. Prohexadione-Ca, benzothiadiazole + metalaxyl, and harpin protein applications reduced disease severity on inoculated shoots compared with copper and untreated controls. Prohexadione-Ca reduced both shoot length and shoot blight on the two hosts. Humic acid applications were ineffective in controlling fire blight on loquat and quince cultivars. Quince cv. Eşme showed lower disease severity than cv. Ekmek (P ≤ 0.05). The use of resistance-inducing substances during the early phase of shoot growth may offer a means of managing the shoot blight phase of fire blight disease on quince and loquat.La brûlure bactérienne est l'une des maladies les plus néfastes chez les fruits à pépins. En l'absence de produits efficaces, non phytotoxiques et socialement acceptables pour lutter contre cette maladie causée par Erwinia amylovora chez les pomoïdées, de nouvelles stratégies sont recherchées. La capacité de certains composés pouvant induire de la résistance (prohéxadione-Ca, protéine harpine et benzothiadiazole (acibenzolar-S-méthyle)), de l'acide humique utilisé en tant que fertilisant, de bactéricides (streptomycine et sel de cuivre), ainsi que des combinaisons de cuivre et de produits chimiques à lutter contre la brûlure bactérienne chez des cultivars de néflier du Japon et de cognassier a été évaluée. La prohéxadione-Ca a été appliquée à un taux de 125 mg L-1 sur deux longueurs de pousses (6-12 cm et 15-20 cm), tandis que le benzothiadiazole + métalaxyl (135 mg L-1) et l'harpine (50 mg L-1) ont été appliqués sur des pousses alors qu'elles mesuraient entre 15 et 20 cm, puis à nouveau alors qu'elles mesuraient entre 30 et 35 cm. Chez le néflier du Japon cv. Cukurgobek, un taux d'efficacité d'environ 60 % a été obtenu avec le benzothia- diazole + métalaxyl; cependant, l'ajout de sel de cuivre en a réduit l'efficacité. Sur les cultivars de cognassier, la protéine harpine, utilisée seule et en combinaison avec le sel de cuivre, s'est avérée le traitement le plus efficace durant les deux années de l'étude, après la streptomycine (P ≤ 0.05). La prohéxadione-Ca, le benzothiadiazole + métalaxyl et les protéines harpines ont réussi à réduire la gravité de la maladie chez des pousses inoculées comparativement aux témoins traités au cuivre et aux témoins non traités. La prohéxadione-Ca a réduit à la fois la longueur et la brûlure des pousses chez les deux hôtes. Les applications d'acide humique n'ont pas réussi à réduire l'incidence de la brûlure bactérienne chez les cultivars de néflier du Japon et de cognassier. Le cognassier cv. Eşme a été moins gravement affecté par la maladie que le cv. Ekmek (P ≤ 0.05). L'utilisation de substances pouvant induire de la résistance durant la phase initiale de croissance des pousses peut être une façon de lutter contre la brûlure des pousses causée par la brûlure bactérienne chez le cognassier et le néflier du Japon

Diversity and Abundance of Hymenopterous Parasitoids Associated with Anastrepha fraterculus (Diptera: Tephritidae) in Native and Exotic Host Plants in Misiones, Northeastern Argentina

Some Major host species used by the tephritid fruit flies Anastrepha fraterculus (Wiede-mann) and Ceratitis capitata (Wiedemann), including Acca sellowiana (O. Berg) Burret, Campomanesia xanthocarpa O. Berg, Psidium guajava L., Prunus persica (L.) Batsch, Eriobotrya japonica (Thunb.) Lindl., Citrus reticulata Blanco var. Murcott, C. aurantium L., C. paradisi Macfadyen var. Dalan Dan, and C. paradisi var. Sudashi, were sampled for fruit fly larvae between Feb and Dec 2000 in the northernmost section of the Paranaense forest, in the Province of Misiones, NE Argentina. Both A. fraterculus and C. capitata were obtained from these host plant species, with A. fraterculus accounting for 93% of all tephritid puparia identified. Ten species of larval-pupal parasitoids were recovered from A. fraterculus; Doryctobracon areolatus (Szépligeti), D. brasiliensis (Szépligeti), Utetes anastrephae (Viereck), Opius bellus (Gahan), Diachasmimorpha longicaudata (Ashmead) (Opiinae, raconidae), Odontosema anastrephae Borgmeier, Lopheucoila anastrephae (Rohwer), Aganaspis pelleranoi (Brèthes) (Eucoilinae, Figitidae), Asobara anastrephae (Muessebeck) (Alyssinae, Braconidae), and Aceratoneuromyia indica (Silvestri) (Tetrastichinae, Eulophidae). All these parasitoids, with the exception of D. longicaudata and A. indica, are native to the Neotropical region. No parasitoids were recovered from C. capitata puparia. Asobara anastrephae and O. anastrephae are newly recorded in Argentina, whereas D. brasiliensis, U. anastrephae, and L. anastrephae are newly reported in Misiones. The eucoiline A. pelleranoi wasthe most abundant parasitoid species. Acca sellowiana and P. guajava harbored the highest parasitoid abundance and diversity.Fil: Schliserman, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Catamarca. Universidad Nacional de Catamarca. Centro de Investigaciones y Transferencia de Catamarca; ArgentinaFil: Ovruski Alderete, Sergio Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Decoll, Olga. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones; ArgentinaFil: Wharton, Robert. Texas A&M University; Estados Unido

Suitability as Medfly Ceratitis capitata (Diptera, Tephritidae) hosts, of seven fruit species growing on the island of São Miguel, Azores

Seven species of fruit were selected to study their suitability as hosts to Ceratitis capitata (Wiedemann). Suitability was determined by evaluating field infestation rates of different host-fruit and by studying the performance of C. capitata reared on these hosts. We sampled old regional cultivars of hot pepper (Capsicum annuum), loquat (Eriobotrya japonica), cattley guava (Psidium littorale), sweet orange (Citrus sinensis) and mandarin (Citrus reticulata); and two introduced fruit plants, feijoa (Feijoa sellowiana cultivar Sellwiana) and peach (Prunus persica cultivar Robidoux). Of the latter, except for mandarin, fruit contained larvae that pupated and yielded viable adults. In the case of mandarins, larvae were detected but none was able to pupate. The percentage of infested fruit was similar among peach, feijoa, sweet orange and hot pepper and, significantly higher than the other hosts (>60%). The highest mean number of pupae and adults per fruit was observed in peach (18.30 and 17.17, respectively) and the lowest in loquat (4.62 and 3.68, respectively). Host-fruit significantly influenced pupal weight, with heavier pupae (0.0124 g) observed in sweet orange. The shortest pupal development time (9.31 days) was observed in hot pepper, whereas the longest (11.99 days) was in feijoa. Adult emergence rates were generally high (>80%), except for sweet orange. Results showed the most suitable host-fruit for C. capitata was peach, followed by cattley guava and feijoa; although loquat and sweet orange were shown to be the less suitable hosts they seem to have an important role as alternative hosts between January and June, allowing the continuous development of C. capitata throughout the year

1-methylcyclopropene and methyl salicylate reduce chilling injury of 'Fukuhara' loquat under cold storage

Este trabalho teve como objetivo verificar o efeito da aplicação de 1-metilciclopropeno (1-MCP) e do salicilato de metila (MeSA) no controle de injúrias pelo frio em nêsperas 'Fukuhara'. Quatro concentrações de 1-MCP foram aplicadas (0, 50, 500 e 5000nL L-1), além do MeSA (0,01mM), associado ou não ao 1-MCP 500nL L-1. Após os tratamentos os frutos foram armazenados a 1&deg;C durante 60 dias. As determinações realizadas foram: firmeza de polpa, índice de escurecimento e podridão, acidez titulável, pH, teor de sólidos solúveis, teor de ácido ascórbico e atividade da enzima polifenoloxidase (PPO). Após 60 dias de armazenamento refrigerado, não foi observado desenvolvimento de escurecimento interno nos frutos tratados com 1-MCP e MeSA. Os frutos controle apresentaram elevados índices de escurecimento interno, juntamente com elevada atividade de PPO. Os frutos apresentaram aumento de firmeza de polpa durante o armazenamento refrigerado, independente do tratamento aplicado.This study was carried out whit the objective to verify the effect of 1-methylcyclopropene (1-MCP) and methyl salicylate (MeSA) in chilling injury control of 'Fukuhara' loquat fruit. It was applied four concentrations of 1-MCP (0, 50, 500 e 5,000nL L-1) and 0,01mM of MeSA associated or not to 500nL L-1 of 1-MCP. The fruit were stored at 1&deg;C during 60 days. The variables analyzed were flesh firmness, pH, titratable acidity, soluble solids content, ascorbic acid content and activity of polyphenol oxidase (PPO). After 60 days of cold storage, there was no development of internal browning in fruit treated with 1-MCP and MeSA. Fruits without treatment showed higher levels of internal browning and high activity of PPO enzyme. All treatments showed increase of flesh firmness during cold storage

Using jasmonates and salicylates to reduce losses within the fruit supply chain

The fresh produce industry is constantly growing, due to increasing consumer demand. The shelf-life of some fruit, however, is relatively short, limited by microbial contamination or visual, textural and nutritional quality loss. Thus, techniques for reducing undesired microbial contamination, spoilage and decay, as well as maintaining product’s visual, textural and nutritional quality are in high demand at all steps within the supply chain. The postharvest use of signalling molecules, i.e. jasmonates and salicylates seems to have unexplored potential. The focus of this review is on the effects of treatment with jasmonates and salicylates on the fresh produce quality, defined by decay incidence and severity, chilling injury, maintenance of texture, visual quality, taste and aroma, and nutritional content. Postharvest treatments with jasmonates and salicylates have the ability to reduce decay by increasing fruit resistance to diseases and reducing chilling injury in numerous products. These treatments also possess the ability to improve other quality characteristics, i.e. appearance, texture maintenance and nutritional content. Furthermore, they can easily be combined with other treatments, e.g. heat treatment, ultrasound treatment. A good understanding of all the benefits and limitations related to the postharvest use of jasmonates and salicylates is needed, and relevant information has been reviewed in this paper