DSpace Collection:

Uso de aeronave remotamente pilotada para aplicação de inibidores de florescimento de cana-de-açúcar

2026-07-24T17:07:06Z

Title: Uso de aeronave remotamente pilotada para aplicação de inibidores de florescimento de cana-de-açúcar Abstract: The use of remotely piloted aircraft (RPAs) in agricultural spraying has been increasing due to their advantages, such as efficient water use and application flexibility. However, further research is necessary to understand the dynamics of this equipment under different working conditions, in order to generate recommendations that improve the quality and safety in the use of this new tool. The aim of this study was to evaluate the quality of the application of flowering inhibitors (florpyrauxifen-benzyl at 0.20 and 0.30 L ha⁻¹ and ethephon at 0.66 L ha⁻¹) using RPAs in sugarcane crops at two application rates (10 and 15 L ha⁻¹), resulting in six treatments and one additional untreated control, all with four replications. The trial was repeated in six locations, of which in two, spray deposition (by detecting a tracer through spectrophotometry) and droplet spectrum (by analyzing water- sensitive paper) were evaluated. In all trials, crop injury symptoms and productivity were assessed. Raw material quality (soluble solid content – BRIX and recoverable sugar – ATR) was also evaluated in three locations, along with the physical-chemical properties of the spray solutions. It was concluded that the choice of product greatly influenced the physical-chemical characteristics of the spray solution. Florpyrauxifen- benzyl led to a greater reduction in surface tension and contact angle of the droplet, indicators directly related to increased spreading and coverage potential on the target surface. However, it also resulted in a smaller volumetric median diameter (VMD), an indicator related to greater risk of drift. Ethephon resulted in higher deposition, possibly related to less interference from drift or volatilization. The use of RPA for the application of flowering inhibitors and the tested application rates were technically viable and safe for sugarcane cultivation, with the observed injuries related to the sensitivity of variety RB96 6928 and not to the application technology itself.

Deposição e eficácia da aplicação de calda herbicida com aeronave remotamente pilotada em função de taxas de aplicação e classes de gotas

2026-06-12T06:24:14Z

Title: Deposição e eficácia da aplicação de calda herbicida com aeronave remotamente pilotada em função de taxas de aplicação e classes de gotas Abstract: Brazilian agriculture stands out on the global stage for its high productivity and increasing adoption of sustainable technologies. In this context, remotely piloted aircraft (RPAs) have emerged as a rapidly adopted technological innovation for the application of pesticides. However, several technical questions challenge farmers and professionals when it comes to herbicide application. This study aimed to evaluate the effects of application rate (10, 20, and 150 L ha⁻¹) and droplet size (medium and coarse) on the weed control efficacy of glyphosate + carfentrazone-ethyl applied using RPA equipped with rotary atomizers and a backpack sprayer. To this end, two field experiments were conducted in an area with high infestation of Ipomoea triloba, Alternanthera tenella, and Commelina benghalensis. Spray quality was characterized by evaluating the volumetric median diameter (VMD), relative span (RS), potential drift risk (PDR), droplet density (droplets cm-2), coverage (%), and deposition (µg cm-2). Weed control efficacy was determined by assigning field scores (3, 7, 14, 21, and 28 DAA). The results indicate that rotary atomizers produced droplets in the “Fine” and “Medium” classes. The application rate of 10 L ha-1 was equal to the rate of 20 L ha-1 in most evaluations, especially in Experiment 2. Applications with RPA (10 and 20 L ha-1) produced a VMD lower than 205,41 μm, while hydraulic nozzles (GRD 120015 and ULD 120015), used in ground applications (150 L ha-1), produced a VMD greater than 484,59 μm. In general, both application methods resulted in similar RA and droplet density. Aerial applications showed higher PDR (>24,94%) compared to ground applications (<1,66%). Ground applications (>23,52%) promoted higher coverage than aerial applications (<3,58%). Despite lower coverage, RPA promoted depositions similar to ground applications. In conclusion, RPA applications promoted high levels of control (> 90%), comparable to ground applications.

Qualidade e produtividade de alho-semente em função dos pontos de colheita e métodos de secagem

2026-03-18T06:23:04Z

Title: Qualidade e produtividade de alho-semente em função dos pontos de colheita e métodos de secagem Abstract: Garlic (Allium sativum L.) is a crop of high economic importance that is vegetatively propagated; thus, its productivity and commercial quality depend directly on the quality of the seed garlic used. Determining the harvest stage and post-harvest management, particularly bulb drying methods, are key factors for maintaining the physiological and structural quality of propagative material and the productive performance of the subsequent generation. However, information regarding the interaction between these factors remains limited under Brazilian Cerrado growing conditions. Therefore, this study aimed to evaluate the influence of different harvest stages and drying methods on the productivity and quality of seed garlic (cv. Ito). The experiment was conducted in Rio Paranaíba, Minas Gerais, Brazil, using a randomized block design arranged in a 3 × 2 factorial scheme with five replications. Treatments consisted of three harvest stages (early, normal, and late) combined with two drying methods (natural curing by hanging and artificial drying). Biometric evaluations were performed at 50, 89, 110, and 134 days after planting, in addition to bulb classification based on diameter, skin integrity, and estimated yield. Harvest stage was the main factor associated with seed garlic performance, influencing dry matter accumulation, bulb physical integrity, and the distribution of commercial classes. Harvesting at normal and late stages increased the proportion of higher commercial classes (>6), which have greater economic value, and resulted in a higher proportion of closed bulbs, whereas early harvesting restricted bulb filling and increased the occurrence of open bulbs. The drying method showed a complementary effect, acting predominantly on bulb physical attributes and the maintenance of the structural quality of planting material. Artificial drying was more efficient for materials harvested early, reducing structural losses, while natural curing by hanging showed equivalent performance when associated with the normal harvest stage.

Potencial fisiológico e sanitário de sementes de soja tratadas com Trichoderma spp. no controle de Sclerotinia sclerotiorum

2026-03-05T06:20:04Z

Title: Potencial fisiológico e sanitário de sementes de soja tratadas com Trichoderma spp. no controle de Sclerotinia sclerotiorum Abstract: The sanitary and physiological quality of soybean seeds is compromised by their association with Sclerotinia sclerotiorum, affecting the initial establishment of the crop and contributing to disease dissemination in the field. The objective of this study was to evaluate the effect of different inoculum potentials of S. sclerotiorum on seed quality, as well as the efficiency of biological control using Trichoderma. The experiment was conducted in a completely randomized design, arranged in a 5×5 factorial scheme, consisting of five inoculum potentials (0, 6, 12, 24, and 48 hours) and five control methods (three Trichoderma isolates, a chemical fungicide, and water).Sanitary quality was assessed by fungal incidence, and physiological quality was determined through germination, radicle protrusion, emergence, and seedling length tests, complemented by analyses of speed, uniformity, growth, and vigor indices. It was observed that increasing inoculum potential resulted in higher pathogen incidence and a progressive reduction in seed quality. Under higher inoculum pressure, the chemical fungicide was more efficient in maintaining physiological performance. The biological control agents showed variable effects depending on the isolate; however, overall, they were able to mitigate the effects of the pathogen at intermediate inoculum potential. It is concluded that increasing the inoculum potential of S. sclerotiorum increases pathogen colonization and incidence in seeds. The physiological quality of seeds is progressively reduced as inoculum potential increases, affecting germination, emergence, and vigor. The fungicide showed greater efficiency in control, whereas biological control with Trichoderma spp. is influenced by inoculum pressure.