The invasive pest
Drosophila suzukii
(Matsumura) (Diptera: Drosophilidae) was recently recorded in Brazil and constitutes a threat to fruit growing, mainly for small, soft fruits. Recent advances in ...research on ways of controlling
D. suzukii
involve the use of entomopathogenic nematodes (EPNs). In this context, the objective of this study was to evaluate the pathogenicity and virulence of four isolates in different concentrations against
D. suzukii
pupae. The EPN isolates used in trials were
Steinernema brazilense
IBCBn 06,
S. carpocapsae
IBCBn 02,
Heterorhabditis bacteriophora
HB, and
H. amazonensis
IBCBn 24. Both
H. amazonensis
IBCBn 24 and
H. bacteriophora
HB were effective in controlling
D. suzukii
as they caused a mortality rate of 86.25% and 80.0%, and virulence of 549.75 IJs/pupae and 787.75 IJs/pupae in the concentrations of 1800 IJs/ml and 5400 IJs/ml, respectively. The lowest lethal concentrations (LC
50
) of juveniles were found in host pupae with 771.63 IJs/ml of
H. bacteriophora
HB and 1115.49 IJs/ml of
H. amazonensis
IBCBn 24. Results showed that both EPNs,
H. amazonensis
IBCBn 24 and
H. bacteriophora
HB, could be promising eco-friendly biological agents to control
D. suzukii
.
The carambola fruit fly
Bactrocera carambolae
Drew and Hancock (Diptera: Tephritidae) is an invasive fruit fly reported in North Brazil that threatens Brazilian fruit culture. Assessing the potential ...risk of establishing this pest is necessary to reduce the threat of
B. carambolae
dispersion to other countries and Brazilian regions and to avoid damage to the fruit trade. In this study, the CLIMEX model was used to understand the response of
B. carambolae
to climate change and to determine its potential global distribution with and without irrigation practices. Based on ecophysiological parameters, the model simulates factors limiting species distribution concerning the climate. To assess the seasonal variation in the density of
B. carambolae
, monitoring data in Uiramutã municipality, Roraima, from 2013 to 2019 was used. According to the CLIMEX forecast, large parts of America, Africa, and Asia, mainly in areas closest to the equator, are highly suitable for the survival of
B. carambolae
. Brazil is a good part of its territory with high suitability for
B. carambolae
, especially the North, South, and Southeast regions and the entire coastal area. The periods of the highest climatic suitability in the five Brazilian regions were January–May and October–December. The potential distribution area expands under irrigation and is highly suitable for most areas without cold stress. The CLIMEX model for B
. carambolae
generated in the present study provides important information for the Brazilian eradication program and other surveillance activities established in pest-free areas.
Fruit loss to birds is a long-standing and costly problem for many producers. We conducted a survey of Honeycrisp apple, blueberry, cherry, and wine grape growers in California, Michigan, New York, ...Oregon, and Washington to estimate costs of bird damage and benefits of bird damage management. We also assessed grower perceptions of impacts on profits and effectiveness of bird management techniques. Current yield-loss estimates provided by growers and market price data were used to monetize current bird damage in each crop and growing region. Data on expected damage without management were used to estimate the benefits of bird damage management as it is currently being employed in the different crops and growing regions. We estimated that current bird damage costs per hectare ranged from $104 in Oregon tart cherries to $7267 in Washington Honeycrisp apples. Estimated benefits of bird management ranged from $299 per hectare in Oregon tart cherries to $36,851 in California blueberries. Aggregate bird damage in the five crops and states was estimated at $189 million, and the aggregate benefits of managing that damage were estimated at $737 million to $834 million. Growers viewed most techniques for bird damage management as ineffective, or only slightly effective, and a majority of blueberry and sweet cherry growers viewed bird damage as having a significant impact on profits. Enhancing the effectiveness of bird damage management would increase both the efficiency and profitability of fruit production.
•Bird damage per acre ranged from $42 in Oregon tart cherries to $2941 in Washington Honeycrisp apples.•Benefit of bird management per acre ranged from $121 in Oregon tart cherries to $14,913 in California blueberries.•Total bird damage in five crops and states was estimated at $189 million.
•Exclusion, sterilisation and disruption offer a different paradigm in pest management.•Exclusion (netting) can be used in the most diverse settings.•Sterile insect release (SIT) is the most ...selective but also costly.•Mating disruption is the easiest to implement at the farm level.
Because of their perennial nature, orchards harbor one of the most complex ecosystems in agriculture. Nevertheless, crop protection programs still mainly focus on pesticides (synthetic or organic-approved) to prevent or limit the action of so-called noxious species in these systems. Killing agents represent the dominant paradigm and have been used in agriculture for decades. This paper synthesizes the available literature about the other approaches, more suited to organic farming, which recognize that the radicalness of killing is not necessary to prevent crop losses. Exclusion barriers represent one of the most readily available means of protecting the crop that way, but other behavior-based techniques have been developed, such as sterile insect technique and mating disruption. While there are many other possibilities, these are the three approaches that are currently getting the most interest in tree fruit production, due to ecological and agronomical characteristics, some of which will be detailed in this review.
Huanglongbing (HLB) or “citrus greening” is the most destructive citrus disease worldwide. In this work, we studied host responses of citrus to infection with Candidatus Liberibacter asiaticus ...(CaLas) using next-generation sequencing technologies. A deep mRNA profile was obtained from peel of healthy and HLB-affected fruit. It was followed by pathway and protein-protein network analysis and quantitative real time PCR analysis of highly regulated genes. We identified differentially regulated pathways and constructed networks that provide a deep insight into the metabolism of affected fruit. Data mining revealed that HLB enhanced transcription of genes involved in the light reactions of photosynthesis and in ATP synthesis. Activation of protein degradation and misfolding processes were observed at the transcriptomic level. Transcripts for heat shock proteins were down-regulated at all disease stages, resulting in further protein misfolding. HLB strongly affected pathways involved in source-sink communication, including sucrose and starch metabolism and hormone synthesis and signaling. Transcription of several genes involved in the synthesis and signal transduction of cytokinins and gibberellins was repressed while that of genes involved in ethylene pathways was induced. CaLas infection triggered a response via both the salicylic acid and jasmonic acid pathways and increased the transcript abundance of several members of the WRKY family of transcription factors. Findings focused on the fruit provide valuable insight to understanding the mechanisms of the HLB-induced fruit disorder and eventually developing methods based on small molecule applications to mitigate its devastating effects on fruit production.
Background: Winter chill is one of the defining characteristics of a location's suitability for the production of many tree crops. We mapped and investigated observed historic and projected future ...changes in winter chill in California, quantified with two different chilling models (Chilling Hours, Dynamic Model). Methodology/Principal Findings: Based on hourly and daily temperature records, winter chill was modeled for two past temperature scenarios (1950 and 2000), and 18 future scenarios (average conditions during 2041–2060 and 2080–2099 under each of the B1, A1B and A2 IPCC greenhouse gas emissions scenarios, for the CSIRO-MK3, HadCM3 and MIROC climate models). For each scenario, 100 replications of the yearly temperature record were produced, using a stochastic weather generator. We then introduced and mapped a novel climatic statistic, “safe winter chill”, the 10% quantile of the resulting chilling distributions. This metric can be interpreted as the amount of chilling that growers can safely expect under each scenario. Winter chill declined substantially for all emissions scenarios, with the area of safe winter chill for many tree species or cultivars decreasing 50–75% by mid-21st century, and 90–100% by late century. Conclusions/Significance: Both chilling models consistently projected climatic conditions by the middle to end of the 21st century that will no longer support some of the main tree crops currently grown in California, with the Chilling Hours Model projecting greater changes than the Dynamic Model. The tree crop industry in California will likely need to develop agricultural adaptation measures (e.g. low-chill varieties and dormancy-breaking chemicals) to cope with these projected changes. For some crops, production might no longer be possible.
A fruticultura é de grande importancia para o agronegócio brasileño e dentre as variedades produzidas, a pitaya vem ganhando destaque devido a ser urna especie exótica que atrai a atenção dos ...produtores pela capacidade de produção durante o ano inteiro e pela alta lucratividade. Porem, um dos maiores problemas dos produtores rurais é a escolha da variedade, levando em consideraçao criterios quali-quantitativos, como produtividade, demanda, custos, cor, sabor e entre outros. Assim, objetiva-se corn este trabalho selecionar dentre as variedades de pitayas disponíveis no mercado, aquelas que mais se adaptam as necessidades de um estabelecimento rural a fim de viabilizar a produção do fruto a partir da aplicação do método de decisão em grupo: PROMETHEE GDSS. O estudo foi realizado na empresa Reda Agrícola durante o período de 01/06/2022 a 31/09/2022. A partir dos resultados obtidos corn a aplicação da modelagem de decisão, foi recomendado o plantío da variedade Costa Rica ou a Golden israelense. Conclui-se, então, que dentro das particularidades apresentadas por todos os stakeholders, o processo decisorio estruturado pelo PROMETHEE GDSS conseguiu ser eficaz no ordenamento das alternativas (variedade de pitayas), satisfazendo as demandas dos decisores e resultando em urna escolha mais sólida e estruturada, a fim de maximizar a chance de sucesso na implantação desta variedade agrícola.
Rainfall, runoff and soil loss from 6
m
×
12
m plots were recorded during 7 years (2000–2006) in an experiment in which three different soil management systems were compared in a young olive grove ...installed on a heavy clay soil, near Cordoba, Southern Spain. The no-tillage (NT) system, kept weed-free with herbicides, had both the largest soil loss (6.9
t
ha
−1
year
−1) and the highest average annual runoff coefficient (11.9%). By contrast, a cover crop (CC) of barley, reduced the soil losses to 0.8
t
ha
−1
year
−1 and the average annual runoff coefficient to 1.2%. Conventional tillage (CT), had intermediate values of soil loss (2.9
t
ha
−1
year
−1) and an average runoff coefficient of 3.1%. The different treatments were established 4 years after planting the olive trees, and a significant decrease in soil and runoff losses was observed with time as the olive trees grew and their canopies developed. Measurements at the end of the experiment showed a significant improvement in the topsoil properties of the CC treatment as compared to CT and NT. The soil under NT presented a significant degradation with respect to traditional CT management. Organic matter values were 2.0, 1.4 and 1.0%, and stability in water of macroaggregates was 0.452, 0.418 and 0.258
kg
kg
−1 for CC, CT and NT, respectively. These results indicate that the use of a cover crop can be a simple, feasible soil and water conservation practice in olive groves on rolling lands in the region. A key factor in its practical use is to establish it early enough to protect the soil in the critical initial years of the grove, when most of the soil is unprotected by the small olive canopy.
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•T. polysporum controlled efficiently melon wilt in a naturally infested crop field.•T. polysporum and fertigation with liquid compost had a synergist effect on control.•Synergism ...between T. polysporum and liquid compost doubled fruit production.
The control of melon wilt caused Fusarium oxysporum f. sp. melonis (Fom) has become a complex problem for melon (Cucumis melo L.) growers worldwide. In this study, we evaluated the ability of Trichoderma spp. to control melon wilt under field conditions, and the application of liquid compost as a food-based strategy to improve the biocontrol efficiency of the selected strain. In a first experiment, we evaluated the use of Trichoderma harzianum LCB47, Trichoderma viride LCB48, Trichoderma koningii LCB49, and Trichoderma polysporum LCB50 to control melon wilt in a naturally infested soil. The treatment with T. polysporum LCB50 (Tp) showed the highest efficiency to control melon wilt (44.85%), increasing the fruit yield in 43%. In the second experiment, Tp was applied as seed treatment, and repeated once at 15days after transplanting. Two doses of liquid compost: 25 (LC25) and 50mLpL−1 (LC50), were applied by fertigation on a weekly basis along the crop development. In this experiment, T. polysporum LCB50 applied alone resulted in a significant (P<0.05) control of wilt (32.2%), and 27% increase in fruit production. Single application of both doses of LC did not significantly reduced disease incidence. However, a strong synergistic effect was observed applying Tp and LC25 and LC50, resulting in a highly significant wilt control (68 and 72%, respectively) and an increase in productivity. The use of Tp+LC50 treatment increased in 100% the production of commercial fruits. From the results, a strategy based on the use of T. polysporum LCB50 and an organic matter source is proposed for the integrated management for melon wilt.
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