A proteção das sementes contra pragas e doenças nas fases iniciais do desenvolvimento da cultura é de grande importância para a cadeia produtiva da soja. A aplicação de inseticidas e fungicidas via revestimento de sementes proporciona esta proteção, no entanto, não deve ocasionar prejuízos à qualidade fisiológica dos lotes de sementes, seja imediatamente depois do revestimento ou após armazenamento. Para avaliar o efeito do revestimento de sementes de soja com vários agroquímicos sobre a qualidade fisiológica das mesmas durante o armazenamento, foram realizados dois ensaios com as cultivares M6972 IPRO e M7739 IPRO. Vinte quilogramas de cada cultivar foram submetidos a revestimento com os produtos Cropstar, Derosal Plus, Standak Top e Avicta Completo, avaliando -se a primeira contagem de germinação, germinação, envelhecimento acelerado e emergência em canteiro das sementes, durante 60 dias de armazenamento sob condições ambientais não controladas. O armazenamento sob condições de temperatura e umidade relativa não controladas influencia negativamente a qualidade fisiológica das sementes de soja. As cultivares usadas responderam de forma diferente ao revestimento de sementes com os diferentes agroquímicos testados. O revestimento de sementes de soja da cultivar M6972 IPRO com Standak Top ou com Avicta Completo mantem a percentagem de emergência de plântulas durante os 60 dias de armazenamento. O revestimento de sementes de soja da cultivar M7739 IPRO com Standak Top ocasiona maior qualidade fisiológica de sementes do que os demais revestimentos. Palavras -chave: fitofármacos, fungicida, Glycine max, inseticida, tratamento de sementes. A B S T R A C TThe protection of seeds against pests and diseases in the early stages of crop development is of great importance to the soybean production chain. Coating seeds with insecticides and fungicides provides this protection; however, it should not cause damage to the physiological quality of seed lots, immediately after coating or after storage. To evaluate the effect of soybean seed coating with various agrochemicals on the physiological quality of seeds during storage, two assays were conducted with the cultivars M6972 IPRO and M7739 IPRO. Twenty kilograms of each cultivar were subjected to coating with products Cropstar, Derosal Plus, Standak Top and Avicta Completo, evaluating the first counting of germination, germination, accelerated aging and seedling emergence of seeds for 60 days of storage under environmental conditions. Storage under not controlled conditions of temperature and relative humidity negatively influences the physiological quality of soybean seeds. The cultivars used responded differently to the seed coating with different agrochemical tested. Soybean seed coating of cultivar M6972 IPRO with Standak Top or Avicta Completo maintains the percentage of seedling emergence during the 60 days of storage. Soybean seed coating of cultivar M7739 IPRO with Standak Top brings better physiological seed quality than other coatings.

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ABSTRACT: This study aimed to evaluate the effect of different levels of self-seeding Italian ryegrass (Lolium multiflorum Lam.) and nitrogen rates - applied additionally after two defoliations - on plant structure, in forage and seed yield. Levels of self-seeding were classified as very high (777 kg ha-1), high (736 kg ha-1), intermediate (624 kg ha-1), and low (234 kg ha-1). Populations were fertilized with zero, 20.25, 40.50, and 60.75 kg ha-1 of supplemental nitrogen applied after two defoliations; respectively, in very high, high, intermediate, and low levels. Higher levels of self-seeding promoted greater forage yield and uniformity of vegetation structure. Number of fertile tillers and number of seeds per plant have benefited by the combination of high self-seeding and supplemental nitrogen fertilization. Despite influencing the uniformity and amount of forage obtained in two defoliations, the very high and low self-seeding levels did not differ in Italian ryegrass seed production. However, linear addition for this same variable was obtained with the inclusion of supplemental nitrogen fertilization. In pastures from low and intermediate self-seeding levels, total dry mass increases linearly with the levels of nitrogen fertilization assessed in this research.

O objetivo deste trabalho foi testar misturas de fungicidas, inseticidas e biorreguladores, no tratamento de sementes, sobre a qualidade fisiológica de sementes de soja. O tratamento de sementes com quaisquer das misturas testadas contribuiu para que a perda de vigor das sementes, causada pelo armazenamento, fosse mais lenta quando comparada com sementes sem tratamento.O objetivo deste trabalho foi testar misturas de fungicidas, inseticidas e biorreguladores, no tratamento de sementes, sobre a qualidade fisiológica de sementes de soja. O tratamento de sementes com quaisquer das misturas testadas contribuiu para que a perda de vigor das sementes, causada pelo armazenamento, fosse mais lenta quando comparada com sementes sem tratamento.

After sowing, seeds are exposed to the action of soil pests and adverse environmental conditions that can reduce the expression of their physiological potential. A solution to these problems is the seed treatment with insecticides to protect the seeds and seedlings against the action of pests and to promote plant growth. The aim of the experiment was to evaluate the influence of thiamethoxam combined with storage on the physiological performance of bean seeds, IAPAR Siriri cultivar. Seeds were treated with Crusier 350 FS ® in doses of 0, 100, 200, 300, 400 and 500 mL 100 kg-1 of seeds, and for evaluation of treatment effect, seeds were submitted to germination and vigor tests (accelerated aging, cold test and emergence in seedbed) at 0, 3, 6, 9 and 12 months after treatment in a completely randomized 6 x 5 factorial design with four replications. Treatment of bean seeds with thiamethoxam doses between 200 and 300 mL 100 kg-1 of seeds allows germination and vigor expression as well as storage potential under controlled conditions, decreasing the rate of germination loss over time.

Produtividade e características agronômicas da soja em função de falhas na semeadura Yield and agronomic characteristics of soybean regarding sowing failure RESUMO: A desuniformidade na distribuição de plantas ao longo da linha de semeadura implica em um aproveitamento ineficiente dos recursos disponíveis, como luz, água e nutrientes, provocando perdas na produtividade decorrentes da competição intraespecífica na população de plantas. O objetivo deste trabalho foi determinar o efeito da plasticidade de plantas de soja de uma população em função de falhas na semeadura e sua relação com a produtividade. Em dois campos de produção comercial de soja, semeados com as cultivares Fundacep 59 RR e BMX Potência RR, foram identificadas diferentes distribuições de espécimes ao longo da linha de semeadura, observando-se a presença de plantas individuais, duplas, triplas e falhas de vários tamanhos dentro de um metro linear de semeadura. As características agronômicas e as produtividades por espécime e por área de suas diferentes distribuições foram avaliadas. Com a ocorrência de falhas na linha de semeadura, o aumento da produção das plantas localizadas nas bordas de falhas não compensa a perda de produção causada pela lacuna nas linhas. Sua adequada distribuição ao longo da linha de semeadura proporciona maior produtividade na cultura da soja. A ocorrência de plantas duplas ou triplas em uma população diminui a produtividade.

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Soybean production accounts for approximately 43% of Brazil's grain produce, worth over 81 million tons for the 2012-2013 cropping season. The use of quality seeds is essential for a high-yield agriculture, since low quality seeds compromise plant standing and increase production costs due to reseeding. This will in turn reduce yields through delays on the establishment dates. Seed quality is affected by relative humidity levels, mechanical damage during harvest and processing, thermal damage during the drying process and the environmental conditions during storage that could foster insect and fungi damage. The climate in the state of Santa Catarina favors soybean seed production, and seed companies in general work with high levels of technology. This work is aimed at characterizing the physical and sanitary quality of soybean seeds produced by different companies at different locations throughout the state of Santa Catarina (municipalities of Xanxerê, Abelardo Luz, Campos Novos and Canoinhas). The physical purity, moisture level, sanitary quality and mechanical damage of soybean seeds were studied at three stages, i.e. reception at the seed processing unit, at the end of the processing process and before being marketed. Results pointed out at mechanical injury and cultivar mixture as the main issues concerning seed lot quality, and that soybean seeds produced in Santa Catarina show pathogen contamination, which emphasizes the need for seed treatment.