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Há poucos trabalhos na literatura que enfatizam a resposta do algodoeiro em cultivo adensado à doses de nitrogênio, fósforo e potássio, pois esse sistema cultivo foi adotado apenas recentemente no Brasil. Dessa forma, objetivou-se com esse trabalho avaliar as características agronômicas do algodoeiro sob o sistema adensado de cultivo em função de doses de nitrogênio, fósforo e potássio em região de Cerrado de altitude elevada. Foram estabelecidos três experimentos com tratamentos referentes a cinco doses (0, 60, 80, 100 e 120 kg ha-1) de N, P2O5 e K2O. Os parâmetros analisados na cultura foram: população de plantas (plantas ha-1); altura de plantas (m); número de capulhos por planta, massa de 15 capulhos (g) e produtividade de algodão em caroço (kg ha-1). A adubação nitrogenada incrementou a produtividade do algodoeiro até a dose estimada de 47 kg ha-1, porém tanto a adubação fosfatada quanto a potássica não influenciaram a produtividade de algodão em caroço.

One of the main limitations of soybean production is related to water availability and organisms found in the soil. Under the hypothesis that soil moisture may influence the nematode population, this study aimed to verify the occurrence of nematodes associated with different irrigation management in soybean crops. The experiment was carried out in a randomized block design. Treatments consisted of a subplot scheme, with four replications. The plots consisted of ten irrigation managements divided into five irrigation frequencies (1,2,3,4, and 5 days) and five additional water depths (25, 50, 75, 100, and 125% of crop evapotranspiration – Etc). The subplots were composed of four different soybean cultivars (NA 5909 RR, AS 3680 IPRO, and Desafio RR ePower IPRO). The experiment analyzed the variables plant height, first pod insertion, number of plants, moisture, hundred-grain weight, yield, and occurrence of nematode eggs and adults. Nematodes influence all the production components analyzed, affecting mostly the hundred-grain weight, especially the nematode Helicotylenchus sp., although the Meloidogyne sp. population was larger. The phytonematode population reduces with the increase in soil moisture to levels close to the saturation, indirectly influencing the yield increase.

One of the main limitations of soybean production is related to water availability and organisms found in the soil. Under the hypothesis that soil moisture may influence the nematode population, this study aimed to verify the occurrence of nematodes associated with different irrigation management in soybean crops. The experiment was carried out in a randomized block design. Treatments consisted of a subplot scheme, with four replications. The plots consisted of ten irrigation managements divided into five irrigation frequencies (1,2,3,4, and 5 days) and five additional water depths (25, 50, 75, 100, and 125% of crop evapotranspiration – Etc). The subplots were composed of four different soybean cultivars (NA 5909 RR, AS 3680 IPRO, and Desafio RR ePower IPRO). The experiment analyzed the variables plant height, first pod insertion, number of plants, moisture, hundred-grain weight, yield, and occurrence of nematode eggs and adults. Nematodes influence all the production components analyzed, affecting mostly the hundred-grain weight, especially the nematode Helicotylenchus sp., although the Meloidogyne sp. population was larger. The phytonematode population reduces with the increase in soil moisture to levels close to the saturation, indirectly influencing the yield increase.