Bean leaf beetle, Cerotoma trifurcata (Forster) (Coleoptera: Chrysomelidae), is an economic pest of soybean in Ontario. Field cage studies were conducted in 2010-2011 to determine voltinism in southern Ontario and the effect of C. trifurcata feeding during soybean reproductive stages on soybean yield and quality. Thermal requirements for C. trifurcata development were determined in a laboratory study. Results of field and laboratory studies support the occurrence of one generation of C. trifurcata in southern Ontario. Pod-feeding increased with both number of beetles and soybean reproductive stage. An increase in defoliation and a reduction in seed quality were observed with increasing number of beetles. Monitoring programs for late-season pod-feeding should begin when degree days approach 500 (base 9.31°C). Economic thresholds for C. trifurcata during soybean reproductive stages range from 0.27 to 2.00 beetles per plant or 8 to 60 beetles per m of row. / Ontario Ministry of Agriculture and Food – University of Guelph Sustainable Production (Plants) Program and Grain Farmers of Ontario through the Farm Innovation Program.

Submitted by RICARDO SALLES TINOCO null (tinoco.rs@gmail.com) on 2016-09-05T17:55:55Z No. of bitstreams: 1 Tese_Ricardo_Salles_Tinôco.pdf: 3233887 bytes, checksum: f65245f5717f6d1e7bba353e15c39c11 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-08T20:37:53Z (GMT) No. of bitstreams: 1 tinoco_rs_dr_jabo.pdf: 3233887 bytes, checksum: f65245f5717f6d1e7bba353e15c39c11 (MD5) / Made available in DSpace on 2016-09-08T20:37:53Z (GMT). No. of bitstreams: 1 tinoco_rs_dr_jabo.pdf: 3233887 bytes, checksum: f65245f5717f6d1e7bba353e15c39c11 (MD5) Previous issue date: 2016-08-05 / O óleo de palma destaca-se por ser a principal fonte alimentícia de óleo vegetal liderando a produção mundial seguido da soja. Devido à escassez de estudos básicos para manejo de desfolhadores em palma de óleo, este trabalho objetivou avaliar a resposta fisiológica das plantas sob desfolha e efeito da desfolha na produção, bem como determinar o nível de dano econômico. Esse trabalho mostrou que a injúria artificial com tesoura e natural por lagartas de B. sophorae não resultou em efeitos no processo fisiológico das folhas remanescentes em mudas de híbrido interespecífico (Elaeis guineensis Jacq. X Elaeis oleifera [Kunth, Cortés]) e, provavelmente, as plantas responderam com mecanismos compensatórios evitando assim interromper seus processos fisiológicos evitando a perda de água, mantendo seu processo autotrófico nos tecidos remanescentes. Os resultados mostraram ainda que a desfolha ocasionada pelas lagartas e a mecânica não apresentaram diferenças e que injúrias mecânicas podem ser usadas em estudos de desfolha simulada. Com isso, justificou-se o uso de desfolha artificial para estudar seu efeito sobre a produção. Paralelamente, obteve-se o consumo de área foliar total para larvas de Opsiphanes invirae Hübner, que foi de 286,064 cm2. O nível de dano econômico foi 5,14 e 2,98 lagartas por folha utilizando o produto Dipel® WP e SC, respectivamente para dados de perdas acumuladas em dois anos. Considerando apenas a injúria artificial obtida nas condições da Agropalma, o NDE utilizando Dipel® WP e SC foi de 3,72 e 2,15 lagartas por folha, respectivamente. Os valores atualmente adotados empiricamente para tomada de decisão pelas empresas são superiores aos valores encontrados nesse estudo, mostrando que devem ser revistos. / Palm oil is notable for being the main food source of vegetable oil leading the world production followed by soybeans. Due to the shortage of basic studies for management of palm oil defoliators, this study aimed to evaluate the physiological response of plants under defoliation and effect of defoliation on the production, as well as to determine economic injury level. This work showed that the artificial injury using scissors and natural using B. sophorae larvae did not result in effects to the physiological process of the remaining leaves in interspecific hybrid seedlings (Elaeis guineensis Jacq. X Elaeis oleifera [Kunth, Cortés]) and, probably, the plants responded with compensatory mechanisms avoiding interruption of the physiological processes preventing the loss of water, keeping the autotrophic process in the remaining tissues. The results also showed that the defoliation either caused by the larvae or by scissors did not show differences and mechanical injuries can be used in simulated defoliation studies. Thus, this justified the use of artificial defoliation to study its effect on production. At the same time, the consumption of total leaf area was obtained for Opsiphanes invirae Hübner larvae, which was 286.064 cm2 and the level of economic damage to this species in oil palm. The economic injury level was 5.14 and 2.98 larvae per leaf using the product Dipel® WP and SC, respectively, using two-year loss data. Considering only the artificial injury obtained at Agropalma, the economic injury level using Dipel® WP and SC was 3.72 and 2.15 larvae per leaf, respectively. The current values empirically adopted for decision making by companies are higher than the values found in this study, showing that they must be reviewed.

Separate field studies were started in fall 2005, which continued through fall 2007, to investigate the effect of different levels of European corn borer tunneling on yield in corn grown for grain and to predict spring infestation levels of early season soil insects, specifically white grubs (Coleoptera: Scarabaeidae) and wireworms (Coleoptera: Elateridae) in cornfields. In the first study, model variables included corn growth stage and larvae per plant. In both years of this study, larvae per plant had a significant effect on grain yield. Grain yield was reduced by 13.1 and 3.65% in plants infested with four larvae per plant in 2006 and 2007, respectively. For 2006, linear regression models provided average percent yield loss per larva per plant at 4.1, 6.8, and 1.8% during late vegetative (V12), early silking (R1), and blister (R2) growth stages, respectively. Economic injury levels (EILs) were calculated based on average percent yield reductions across each growth stage and year. In the second study, no significant differences were detected in both fall and spring between two sampling methods after correcting for differences in sampling volume. Strong correlations were observed between fall and spring grub densities in both years. In 2006, fields with grub densities above the spring nominal threshold had significantly greater stand and yield in the Poncho 1250 (1.25 mg clothianidin / kernel) treatment when compared to the Poncho 250 (0.25 mg clothianidin / kernel) and untreated plots. This information was used to develop fall EILs and economic thresholds for white grubs. / Master of Science in Life Sciences

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-05T13:24:15Z No. of bitstreams: 2 Tese - Camila de Souza Queiroz Pinheiro de Belém - 2017.pdf: 1674649 bytes, checksum: 7cce47d8c14114cadc16e229e5212348 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-05T13:24:50Z (GMT) No. of bitstreams: 2 Tese - Camila de Souza Queiroz Pinheiro de Belém - 2017.pdf: 1674649 bytes, checksum: 7cce47d8c14114cadc16e229e5212348 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-05-05T13:24:50Z (GMT). No. of bitstreams: 2 Tese - Camila de Souza Queiroz Pinheiro de Belém - 2017.pdf: 1674649 bytes, checksum: 7cce47d8c14114cadc16e229e5212348 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-31 / The sugarcane borer, Diatraea saccharalis (F.) (Lepidoptera: Crambidae), is an important pest of sugarcane (Saccharum spp.). Galleries are produced within the stalks as a result of the larval feeding. The holes allow the entry of microorganisms and fungi that can modify the technological quality of the raw material that goes to the industry. In this context, the objective was to estimate the influence of infestation intensity of D. saccharalis on the sugarcane technological quality and economic in different varieties. Two experiments were carried out. One with plants collected in September 2014 and another with plants collected in July 2015. In both of them was used completely randomized design with five repetitions. Treatments resulted of a factorial combination between three sugarcane varieties (IAC91-1099, RB86 7515 e CTC 4) and six infestation intensities of D. saccharalis (0%, 20%, 40%, 60%, 80% e 100%). Each plot corresponded to cane internodes with percent internodes with borer and rot corresponding to infestation intensities. The contents of Brix in the juice, Pol in the juice, fiber of the cane, Pol in cane, Purity of the juice, juice reducing sugars, stalk reducing sugar and total recoverable sugar were evaluated. The influence of the infestation intensity of D. saccharalis on sugarcane varies between the varieties and between the harvesting seasons. The presence of red rot in sugarcane does not necessarily imply loss of technological quality. The level of control should not be generalized and should be established taking into account varieties and harvesting carried out in the middle and at the end of the harvest. / A broca da cana, Diatraea saccharalis (F.) (Lepidoptera: Crambidae), é uma importante praga da cana-de-açúcar (Saccharum spp.). As lagartas abrem galerias no interior do colmo ao se alimentarem permitindo a entrada de microrganismos e fungos que podem alterar a qualidade tecnológica da matéria-prima que chega à indústria. Neste contexto, objetivou-se estimar a influência da intensidade de infestação de D. saccharalis na qualidade tecnológica e econômica de diferentes variedades de cana-de-açúcar. Foram realizados dois experimentos. Um com plantas coletadas em setembro de 2014 e outro com plantas coletadas em julho de 2015. Em ambos utilizou-se o Delineamento Inteiramente Casualizado (DIC) com cinco repetições. Os tratamentos foram resultado da combinação fatorial entre três variedades de cana (IAC91-1099, RB86 7515 e CTC 4) e seis níveis de intensidade de infestação de D. saccharalis (0%, 20%, 40%, 60%, 80% e 100%). Cada parcela correspondeu a entrenós de cana com percentual de entrenós com broca e podridão correspondendo às intensidades de infestação. Foram avaliados os teores de Brix no caldo, Pol no caldo, fibra da cana, Pol na cana, Pureza do caldo, açúcares redutores do caldo, açúcares redutores na cana e açúcar total recuperável. A influência da intensidade de infestação de D. saccharalis na cana-de-açúcar varia entre as variedades e colheita realizada no meio e no final da safra. A presença de podridão vermelha na cana-de-açúcar não implica necessariamente em perda de qualidade tecnológica. O nível de controle não deve ser generalizado e deve ser estabelecido levando em consideração variedades e colheita realizada no meio e no final de safra.

During 2013 and 2014, studies were conducted to determine the effects of Helicoverpa zea and Spodoptera frugiperda on both damage and yield of Sorghum bicolor. Results from damage ratings suggest that the amount of damage per single larva decreases as population density increases. Also, yield results suggest that one H. zea and one S. frugiperda larva per panicle results in a 3.6 and 4 percent yield loss, respectively. Additionally, a dynamic EIL was determined using crop value along with various yield potentials and control costs. Other research studies were conducted to determine the efficacy of diamide and pyrethroid insecticides on headworms when applied at midge timing for different locations and planting dates. Results suggest that diamides provide longer and better control of headworms than do pyrethroids. However, applying diamides as a preventative application at midge timing may not be economically feasible when grain prices are low.