RESUMEN

Patagonia (Argentina and Chile) harbors the highest Saccharomyces eubayanus genomic diversity and its widest predominance in natural environments. In this work, S. eubayanus was isolated for the first time from a fermentative environment. This species was found dominating both a traditional apple chicha fermentation as well as feral apple trees in the Andean region of Aluminé (Argentina). S. eubayanus was the only Saccharomyces species found in the isolation substrates, although it coexisted with other non-Saccharomyces species. The absence of strong fermentative competitors of the Saccharomyces genus (like Saccharomyces uvarum or Saccharomyces cerevisiae) in the feral apples could promote the development and implantation of S. eubayanus in a spontaneous apple must fermentation. Phylogeographic analyses revealed a high intraspecific diversity in S. eubayanus, enabling the characterization of strains belonging to the genomic subpopulations PA1, PA2, and PB1 according to the sequences obtained for the intFR gene region. This result evidence that the studied sampling area represents a natural habitat for the species. Being a novel finding, studying the causes that allowed this species to prosper in a fermentative environment becomes essential. Hence, the physiological profile of the new isolates, including their ability to grow at different temperature, nitrogen, and ethanol concentrations was evaluated in comparison with a set of S. eubayanus strains previously isolated from natural environment and representing different genomic subpopulations. Greater physiological diversity was evidenced when strains isolated from both natural and fermentative environments were analyzed overall. Furthermore, no direct relationship between genomic population and physiological behavior was observed; on the opposite, strains appeared to exhibit similar behavior, primarily grouped by isolation origin.

RESUMEN

Geneva® rootstocks in Brazil are known to be efficient in controlling vigor, and are precocious and resistant to diseases. The objective of this study was to evaluate the performance of apple tree cultivars grafted on the Geneva® rootstocks in severe replant disease areas, by planting 60 days after the eradication. The experiments were implemented in 2017, in São Joaquim and Vacaria. The Gala Select and Fuji Suprema cultivars were grafted onto 'G.202', 'G.814', 'G.210', and 'G.213' rootstocks in the Tall Spindle training system. In 2018/2019, total thinning was carried out to promote plant growth. In São Joaquim, partial thinning was carried out in 2019/2020 harvest of 'Gala Select'. The rootstocks were divided into two groups based on vigor, for both areas and cultivars. 'G.202' and 'G.213' were 40% less vigorous than 'G.210' and 'G.814'. For 'Gala Select', the extreme non-fallow condition mainly affected the vigor and productivity of 'G.213' in both areas. At the end of two harvests, 'G.213' was 17% less productive than 'G.210', contrary to what is observed in areas where the fallow period is respected. However, 'G.213' confirmed a greater yield efficiency, which was 27% higher than 'G.210'. This suggests that a perspective of forecasting production for the third crop is higher for 'G.213' than for 'G.210'. In the case of 'Fuji Suprema', the G.210 rootstock was the most productive in both areas. In São Joaquim, 'G.202' matched 'G.210' in productivity and efficiency as it sprouts better in colder regions. Considering the fruit quality, 'G.213' anticipated the maturation with fruits of larger size and higher total soluble solids (TSS) in both areas and cultivars, making it possible to anticipate the harvest. It was concluded that the non-fallow condition does not alter the relative differences in vigor and fruit quality among the rootstocks. However, notwithstanding the overall replant tolerance of these rootstocks, it does reduce productivity by mainly affecting less vigorous rootstocks that need about three crops to overcome the allelopathic effects of the soil and start growing normally. The G.210 semi-dwarfing rootstock is an alternative for the immediate conversion of apple orchards of Gala Select and Fuji Suprema cultivars in southern Brazil.

RESUMEN

The oriental fruit moth, Grapholita molesta (Busk, 1916), is one of the most important pests in apple orchards in southern Brazil. Chemical control is still the most commonly used strategy for pest control. The aim of this study was to determine the resistance evolution of seven South Brazilian populations to four insecticides (chlorantraniliprole, lufenuron, chlorpyrifos, and fenitrothion). Bioassays were paired with metabolic analyses of glutathione-S-transferase (GST), carboxylesterases (α-NA and ß-NA), and acetylcholinesterase (AChE) to understand the possible role with phytosanitary strategies in the insects' susceptibility. Insect populations were collected in the municipalities of Campo do Tenente, Lapa and Porto Amazonas, Fraiburgo, São Joaquim, and Vacaria and multiplied in the laboratory. Two susceptible and two resistant populations were used as references. The bioassays showed that five populations were considered more resistant to organophosphates, six to lufenuron and two to chlorantraniliprole when compared with the sensitive population. None of the field populations had greater resistance than the resistant laboratory population. The enzymatic activity of AChE and GST was elevated in most of the populations that were less susceptible to organophosphates and lufenuron. The populations originating from orchards that used sexual confusion techniques had the greatest susceptibility based on toxicological and biochemical bioassays. Populations under pressure from various compounds had high GST, α and ß-NA activity. There is evidence that a diversity of control strategies can provide better resistance management.

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This study evaluated the diversity of cultivable plant growth-promoting (PGP) bacteria associated with apple trees cultivated under different crop management systems and their antagonistic ability against Colletotrichum gloeosporioides. Samples of roots and rhizospheric soil from apple trees cultivated in organic and conventional orchards in southern Brazil were collected, together with soil samples from an area never used for agriculture (native field). Bacteria were identified at the genus level by PCR-RFLP and partial sequencing of the 16S rRNA, and were evaluated for some PGP abilities. The most abundant bacterial genera identified were Enterobacter (27.7%), Pseudomonas (18.7%), Burkholderia (13.7%), and Rahnella (12.3%). Sixty-nine isolates presented some antagonist activity against C. gloeosporioides. In a greenhouse experiment, five days after exposure to C. gloeosporioides, an average of 30% of the leaf area of plants inoculated with isolate 89 (identified as Burkholderia sp.) were infected, whereas 60 to 73% of the leaf area of untreated plants was affected by fungal attack. Our results allowed us to infer how anthropogenic activity is affecting the bacterial communities in soil associated with apple tree crop systems, and to obtain an isolate that was able to delay the emergence of an important disease for this culture.

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First report and morphological redescription of Teleonemia morio (Stål) (Hemiptera, Tingidae) in Annona squamosa L. (Annonaceae) in Brazil. This is the first report of a severe attack of Teleonemia morio (Stål, 1855) (Hemiptera, Heteroptera, Tingidae) on Annona squamosa L. (custard apple), causing up to 80% of losses of infested trees. In order to facilitate the identification of this insect pest, the adult female of T. morio is redescribed based on specimens collected in Palmeira dos Índios, Alagoas, Brazil.

Primeiro registro e redescrição morfológica de Teleonemia morio (Stål) (Hemiptera, Tingidae) em Annona squamosa L. (Annonaceae) no Brazil. Este é o primeiro registro de um ataque severo de Teleonemia morio (Stål, 1855) (Hemiptera, Heteroptera, Tingidae) em árvores de Annona squamosa L. (pinheira ou fruta-do-conde), resultando em perdas de aproximadamente 80% das plantas infestadas. Com o objetivo de facilitar a identificação deste inseto-praga, foi feita a redescrição da fêmea adulta de T. morio com base em espécimes coletados em Palmeira dos Índios, Alagoas, Brasil.

RESUMEN

Cultivation of temperate-climate fruits is economically important for Brazil. Grapholita molesta Busck is a pest that causes damage to apples, peaches, plums, and pears growing in different micro-regions of southern Brazil, and understanding its reproductive behavior is essential to develop control strategies. The objective of this study was to ascertain the influence of different temperatures (13, 16, 19, 22, and 25ºC) on the oviposition behavior of G. molesta. Females of G. molesta were placed in individual plastic containers, and the pre-oviposition period and the number of eggs laid were assessed until adult death. Temperature influenced the pre-oviposition period, and females kept at 22º were the first to lay their eggs. Oviposition occurred over a longer period of time at 13ºC than at the higher temperatures. The highest total number of eggs was obtained at 19ºC, with the mean daily oviposition being directly proportional to the temperature. There was a negative interaction between the pre-oviposition period and the total number of eggs laid by females. The most suitable temperature for oviposition of G. molesta was 19ºC.

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Foram avaliadas características biológicas de fêmeas de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) linhagem bonagota com três idades sobre ovos deBonagota salubricola (Meyrick) (Lepidoptera: Tortricidae) com cinco períodos de desenvolvimento embrionário. Ovos de B. salubricola com 0-24, 24-48, 48-72, 72-96, 96-120 horas de desenvolvimento embrionário foram oferecidos ao parasitismo por fêmeas de T. pretiosum com 0-24, 24-48 e 48-72 horas de idade, por 24 horas à 25 ± 1º C, 70 ± 10% de umidade relativa e 14 horas de fotofase. Fêmeas do parasitoide com 0-24 horas de vida apresentaram melhores taxas de parasitismo em ovos do hospedeiro com 24-48 horas de desenvolvimento embrionário. Fêmeas com 24-48 e 48-72 horas de vida apresentaram preferência por ovos com 0-24 horas de desenvolvimento embrionário. O percentual de emergência variou entre 20,0 e 60,0%, a razão sexual entre 0,56 e 0,85 e o número de parasitoides/ovo foi superior a um, sem diferença significativa. O ideal para programas de controle biológico de B. salubricola é utilizar o parasitoide na idade de 0-24 horas.

Biological characteristics ofTrichogramma pretiosumRiley (Hymenoptera: Trichogrammatidae) strain bonagota with three ages on eggs of Bonagota salubricola (Meyrick) (Lepidoptera: Tortricidae) at five embryonic developmental stages was studied under laboratory conditions (25 ± 1º C, 70 ± 10% of relative humidity and 14 hours of photophase). B. salubricola eggs with 0­24, 24­48, 48­72, 72­96, 96­120 hours of embryonic developmental stages were offered to T. pretiosum during 24 hours using parasitoid females with 0­24, 24­48 and 48­72 life hours. Parasitoid females with age of 0­ 24 hours showed a higher parasitism rate in eggs of B. salubricola with 24­48 hours of embryonic development. Females with age of 24­48 and 48­72 hours, showed a preference for eggs with 0­ 24 hours of embryonic development. Adult emergence and sex ratio ranged from 20.0 to 60.0% and from 0.56 to 0.85 respectively. The number of parasitoids/egg was always more than one, ranging from 1.03 to 1.14. The ideal for a biological control program of B. salubricola using T. pretiosum strain bonagota is to use parasitoids with a maximum of 24 hours of age.

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ABSTRACT Biological characteristics ofTrichogramma pretiosumRiley (Hymenoptera: Trichogrammatidae) strain bonagota with three ages on eggs of Bonagota salubricola (Meyrick) (Lepidoptera: Tortricidae) at five embryonic developmental stages was studied under laboratory conditions (25 ± 1º C, 70 ± 10% of relative humidity and 14 hours of photophase). B. salubricola eggs with 024, 2448, 4872, 7296, 96120 hours of embryonic developmental stages were offered to T. pretiosum during 24 hours using parasitoid females with 024, 2448 and 4872 life hours. Parasitoid females with age of 0 24 hours showed a higher parasitism rate in eggs of B. salubricola with 2448 hours of embryonic development. Females with age of 2448 and 4872 hours, showed a preference for eggs with 0 24 hours of embryonic development. Adult emergence and sex ratio ranged from 20.0 to 60.0% and from 0.56 to 0.85 respectively. The number of parasitoids/egg was always more than one, ranging from 1.03 to 1.14. The ideal for a biological control program of B. salubricola using T. pretiosum strain bonagota is to use parasitoids with a maximum of 24 hours of age.

RESUMO Foram avaliadas características biológicas de fêmeas de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) linhagem bonagota com três idades sobre ovos deBonagota salubricola (Meyrick) (Lepidoptera: Tortricidae) com cinco períodos de desenvolvimento embrionário. Ovos de B. salubricola com 0-24, 24-48, 48-72, 72-96, 96-120 horas de desenvolvimento embrionário foram oferecidos ao parasitismo por fêmeas de T. pretiosum com 0-24, 24-48 e 48-72 horas de idade, por 24 horas à 25 ± 1º C, 70 ± 10% de umidade relativa e 14 horas de fotofase. Fêmeas do parasitoide com 0-24 horas de vida apresentaram melhores taxas de parasitismo em ovos do hospedeiro com 24-48 horas de desenvolvimento embrionário. Fêmeas com 24-48 e 48-72 horas de vida apresentaram preferência por ovos com 0-24 horas de desenvolvimento embrionário. O percentual de emergência variou entre 20,0 e 60,0%, a razão sexual entre 0,56 e 0,85 e o número de parasitoides/ovo foi superior a um, sem diferença significativa. O ideal para programas de controle biológico de B. salubricola é utilizar o parasitoide na idade de 0-24 horas.

RESUMEN

Neste trabalho foi estudada a capacidade de parasitismo de Trichogramma pretiosum Riley linhagem bonagota, em ovos de Bonagota salubricola (Meyrick), às temperaturas de 18, 20, 22, 25, 28, 30 e 32ºC. Avaliou-se o número diário de ovos parasitados, a porcentagem acumulada de parasitismo, o número total de ovos parasitados por fêmea e a longevidade de fêmeas. O parasitismo durante as primeiras 24h oscilou de 1,6 (32ºC) a 8,8 (22ºC) ovos parasitados por fêmea de T. pretiosum. O parasitismo acumulado de ovos de B. salubricola atingiu 80 por cento no período de 1 a 4 dias a 20°C e 32ºC, respectivamente, e somente no 7º dia, a 18°C. Na faixa térmica de 18°C a 22°C foram obtidos os melhores resultados para o total de ovos parasitados por fêmea, sendo de 35,4 a 24,6, respectivamente. A longevidade média de fêmeas de T. pretiosum a 18°C e 32ºC variou de 7,8 a 2,5 dias, respectivamente. Os resultados evidenciaram que T. pretiosum linhagem bonagota adaptou-se melhor às temperaturas entre 18°C e 22ºC.

The parasitism capacity of Trichogramma pretiosum Riley strain bonagota on Bonagota salubricola (Meyrick) eggs was studied under the temperatures of 18, 20, 22, 25, 28, 30 and 32ºC. The number of days with parasitism, accumulated parasitism, total number of eggs parasitized per female and parasitoid longevity was evaluated. In the first 24h, parasitism ranged from 1.6 (32ºC) to 8.8 (22ºC) eggs of B. salubricola. Accumulated egg parasitism of B. salubricola reached 80 percent in 1st to 4th day at 20ºC to 32ºC, respectively, and in the 7th day at 18°C. Temperatures from 18°C to 22°C were the best suited for the total eggs parasitized for female, resulting in 35.4 and 24.6 eggs/male respectively. T. pretiosum female longevity ranged from 7.8 to 2.5 days, at 18°C and 32ºC, respectively. The results showed that T. pretiosum strain bonagota is better adapted to temperatures from 18°C to 22ºC.

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In order to determine the number of hives per hectare for apple pollination, 5 hives of africanized bees, with ca. 35,000 bees each, labeled with radiophosphorus, were taken to an orchard, one at a time, every 2 days. A circular area of 100 meters diameter (0,8ha), was marked every 10 m from the center to the limit (50m), in two perpendicular directions (cross-shape) pointing out to North-South and East-West directions. The honeybees were collected on apple flowers for 10 min a day during a 10 day period. The experimental area (0.8 ha) was saturated with bees from 5 hives and there was no significant diference between the average number of collected bees with 2, 3, 4 and 5 hives. Consequently, the ideal number of hives per hectare of apple orchard is 2.5 taking into consideration the tested population.

Com o objetivo de se determinar o número de colmeias por hectare para polinização de maçã, foram levadas a um pomar uma a uma, a cada dois dias, 5 colônias de abelhas africanizadas, marcadas com fósforo radioativo (32P). Cada colmeia continha uma população estimada em cerca de 35.000 abelhas. Na área experimental de aproximadamente 0,8 ha, foram demarcadas macieiras a cada 10 m a partir do centro onde estavam as colmeias, formando quatro alas perpendiculares em formato de cruz, até a uma distância de 50m. As abelhas foram coletadas com puçá quando visitavam as flores, durante 10 minutos por dia em cada árvore estaqueada e por 10 dias consecutivos. Pôde-se observar que o número de abelhas marcadas coletadas foi aumentando à medida que se acrescentavam mais colmeias no pomar, sendo que não houve diferença estatística significativa entre o número médio de abelhas coletadas nas flores com 2, 3, 4 e 5 colmeias, concluindo-se então que 2,5 colmeias por ha seriam suficientes para visitar todas as flores do pomar.

RESUMEN

In order to determine the number of hives per hectare for apple pollination, 5 hives of africanized bees, with ca. 35,000 bees each, labeled with radiophosphorus, were taken to an orchard, one at a time, every 2 days. A circular area of 100 meters diameter (0,8ha), was marked every 10 m from the center to the limit (50m), in two perpendicular directions (cross-shape) pointing out to North-South and East-West directions. The honeybees were collected on apple flowers for 10 min a day during a 10 day period. The experimental area (0.8 ha) was saturated with bees from 5 hives and there was no significant diference between the average number of collected bees with 2, 3, 4 and 5 hives. Consequently, the ideal number of hives per hectare of apple orchard is 2.5 taking into consideration the tested population.

Com o objetivo de se determinar o número de colmeias por hectare para polinização de maçã, foram levadas a um pomar uma a uma, a cada dois dias, 5 colônias de abelhas africanizadas, marcadas com fósforo radioativo (32P). Cada colmeia continha uma população estimada em cerca de 35.000 abelhas. Na área experimental de aproximadamente 0,8 ha, foram demarcadas macieiras a cada 10 m a partir do centro onde estavam as colmeias, formando quatro alas perpendiculares em formato de cruz, até a uma distância de 50m. As abelhas foram coletadas com puçá quando visitavam as flores, durante 10 minutos por dia em cada árvore estaqueada e por 10 dias consecutivos. Pôde-se observar que o número de abelhas marcadas coletadas foi aumentando à medida que se acrescentavam mais colmeias no pomar, sendo que não houve diferença estatística significativa entre o número médio de abelhas coletadas nas flores com 2, 3, 4 e 5 colmeias, concluindo-se então que 2,5 colmeias por ha seriam suficientes para visitar todas as flores do pomar.