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Aim of study: The objective was evaluating the peanut combining process quality in three soil tillage systems associated with threshing and separation systems efficiency of peanut combine available on market. Area of study: Brazil. Material and methods: The treatments were three soil tillage systems (conventional, reduced and strip) and two harvesters with different threshing systems. The losses were collected (subdivided in internal mechanisms, pickup platform, and total losses) in fifteen points for each treatment, as impurity samples, following the statistical process control. Main results: The soil tillage only in sowing line reduced the peanut combining quality (30.4% more mineral impurities and 37.7% more vegetal impurities). The machine with tangential flow presented lower capacity of mineral impurity removal, regardless the soil tillage system. Research highlights: The losses were similar for conventional and reduced soil tillages, which indicates that it would be possible to reduce the number of agricultural operations before peanut sowing, consequently lessening costs without loss in process quality.

Sugarcane harvester cutting blade wear increases ratoon damages and losses, impairing sugarcane regrowth. This study aimed to evaluate the quality of basal cut using ratoon damage and loss indexes and correlating them with effects on sugarcane regrowth. Harvest parameters such as plant height and position, damage and loss indexes, and stem length were evaluated every 30 min, following statistical process control (SPC) assumptions. Blade wear was examined during three harvesting shifts (0-8 h, 8-16 h, and 16-24 h). Sugarcane regrowth was assessed by counting number of tillers and measuring plant height and stem diameter. The second harvesting shift showed better quality in terms of damage and loss indexes, and plant height and stem diameter. Harvesting was considered out of control for parameters such as cutting height, number of tillers, plant height, and stem diameter. On the other side, it was regarded as under control for damage and loss indexes, and plant high and position. The first shift presented peripheral or no damages and weak to medium loss levels, whereas the second and third ones showed extreme damages and medium to strong losses.

A profundidade de semeadura e a nutrição das plântulas com micronutrientes na fase de desenvolvimento inicial são imprescindíveis para se atingir o estande recomendado para cultura do milho. Nesse sentido, objetivou-se verificar se o tratamento de sementes com zinco afeta os parâmetros fitotécnicos e fisiológicos no estádio de desenvolvimento inicial da cultura do milho até os 21 dias após a emergência, bem como verificar a relação do tratamento de semente com a profundidade de semeadura. O experimento foi realizado em blocos casualizados com quatro repetições, em esquema fatorial 3x4, sendo duas fontes de zinco (sulfato e óxido de zinco) no tratamento de semente e uma testemunha (sem zinco), combinadas com quatro profundidades de semeadura (2, 4, 6 e 8 cm). Avaliou-se a média do número de dias para a emergência, a porcentagem de germinação, o diâmetro de colmo, a área foliar e o teor de zinco na parte aérea, bem como a eficiência de uso do zinco aos 21 dias. Independentemente da fonte de zinco e das profundidades de semeadura, não foram observadas diferenças em nenhuma das variáveis analisadas. O tratamento de sementes com zinco não afetou os parâmetros germinativos e fisiológicos do milho até os 21 dias após a emergência.