Seed quality is extremely important for agribusiness, as it can affect the stand establishment, as well as the competitive ability of the plant, affecting its yield potential. The aim of the present work was to evaluate the initial development and the production performance of the maize crop as a function of the vigor of the seed lots. The experiment consisted of 10 treatments, involving two factors: two stands (ideal number of plants and ideal number of seeds corrected by the seedling emergence test in bed); and five seed lots as a function of vigor (63, 68, 83, 87 and 99% vigor), according to the results of the cold test. The experimental design was a randomized block design, with four replications. The following parameters were determined along the crop cycle: plant height; chlorophyll and plant cover index; cycle; initial and final populations; and components of grain yield. The use of high-vigor maize seeds favors the initial development of the crop and soil cover, with a positive influence on the number of grains per ear and final population of plants in pre-harvest, in addition to reducing the cycle. High-vigor maize seeds promote gains in yield; for each increase of 1.0 percentage point in the level of seed vigor of the lot, estimated by cold test, the increase in grain production can reach 43.5 kg.ha-1.

Seed treatment is an important procedure in soybean cultivation and is currently performed in two ways: industrial seed treatment (IST), performed by the seed companies industry, and OnFarm treatment, performedby the producer. The objective of this research was to compare the influence of industrial and OnFarm soybean seed treatment technologies, including the machines and processes, on the occurrence of mechanical damage and the functional quality of treatment. Soybean seeds were subjected to phytosanitary treatments with different processes and machines: (1) industrial treatment with a batch process; (2) industrial treatment with a continuous flow process, (3) OnFarm continuous flow treatment with dosage distribution via fixed-volume doser and seed mixing via worm screw; and (4) controlrepresented by untreated seeds. The occurrence of mechanical damage was evaluated by the sodium hypochlorite test. The functional quality of the treatments was analyzed by seed coating, determined by means of digital image processing; particle detachment (dust-off); and dose effectiveness of thiamethoxam, determined by high-performance liquid chromatography (HPLC). The treatment of soybean seeds in batch or continuous flow industrial systems ensures better seed coating, greater dose effectiveness, less particle detachment and a lower occurrence of mechanical damage compared to OnFarm application technology. The digital processing of high-resolution images is efficient for quantifying the coating of soybean seeds by phytosanitary products. Seed coating is directly related to dose effectiveness.

In the soybean crop, seed treatment is widespread, often with the use of several products. The aim of this study was to evaluate the effect of phytosanitary and functional products used in such treatments on the quality of stored soybean seeds. The seeds were treated with combinations of fungicide, insecticide, polymer, finishing powder, graphite, cobalt-molybdenum (CM), and inoculant. Quality evaluations were made at 0, 15, 30, 60, and 90 days of storage after the treatment by means of the following tests: germination, seedling emergence, modified accelerated aging in substrate, primary root length, as well as quantification of dust-off of the seeds. A completely randomized experimental design was used in a 10 × 5 factorial arrangement, involving 10 seed treatment compositions and five storage periods. To avoid harmful effects on physiological quality, CM and graphite added to the phytosanitary products should be used nearer to sowing, in a period of less than 15 days. Seeds with the basic industrial seed treatment used as a technological package in most seed production companies (fungicide, insecticides, and polymer) maintained physiological quality up to 60 days of storage. An excessive number of products use as seed treatment in this study, consisting of more than five, can negatively affect seed quality, even in a short storage period of 15 days. The composition of the treatment directly affects the dust-off of the seeds, especially combinations that include finishing powder and graphite.

The use of an appropriate germination method is crucial to allow expression of the germination potential of the seed lot, especially when the seeds are treated with phytosanitary products, since phytotoxicity can occur in some substrates and under some conditions and the germination values will be underestimated. In this context, the aim of this study was to evaluate the methodology of germination in a rolled paper plus vermiculite (RP+V) and the possibility of its statistical validation for routine use in laboratories. Four seed lots of two cultivars with different vigor levels and chemical insecticide treatments (control, thiamethoxam + cyantraniliprole, clothianidin + fipronil, and imidacloprid + thiodicarb, all seeds were treated with fungicide) were used. The samples were prepared and sent to 13 laboratories accredited by the Ministério da Agricultura e Pecuária (MAPA) for germination assessment with RP+V. The collected data were analyzed using statistical methodologies to assess the repeatability and reproducibility of the method, as well as its precision and accuracy. The data from normal soybean seedlings evaluated using the rolled paper plus vermiculite (RP+V) methodology show repeatability, reproducibility, precision, and accuracy within the critical parameters of 1% and 5%. The proposed methodology is reliable and can be routinely implemented in evaluation of soybean seeds, especially those treated with phytosanitary products.

Seed treatment can be carried out in two modalities: On-Farm or via industrial treatment (IST). Evaluating the quality of the treatment is crucial, considering the percentage of coating by the phytosanitary product and the adequacy of the dose. In this context, the aim of this study was to evaluate the use of high-resolution computerized image analysis to assess the coating of treated soybean seeds. In addition, it was sought to characterize the quality profiles of coating and dose adequacy in treated seeds in the Brazilian agribusiness. 150 samples of seed treated in both modalities were collected from various soybean producers in Brazil and evaluated for the percentage of coating by means of color quantification in high-resolution image analysis and for the percentage of the active insecticide ingredient by means of High Performance Liquid Chromatography (HPLC). Image analysis was effective in quantifying coating, regardless of the dominant color. Coating correlated directly with dose effectiveness in the IST modality. Seeds treated via IST tended to have higher quality and homogeneity of treatment compared to On-Farm treated seeds, showing adequate coating and dose effectiveness. On-Farm treated seeds showed heterogeneity in treatment quality, with significant variation in coating and dose effectiveness.