With the increase of corn cultivation under the no-tillage system, various cover crop species have been evaluated to obtain a soil cover that benefits corn under succession and no-tillage. The objective of this work was to evaluate the effect of three sowing densities of black oat (Avena strigosa Scheig) and common vetch (Vicia sativa) in associated crops and as isolated crops and three levels of nitrogen fertilization (N), applied on corn (0, 60 and 160 kg ha-1 of N). Dry […]

The objective of this work was to evaluate the effects of molybdenum (Mo) leaf application in beans on leaf and grain concentration of Mo, total N, organic N and nitrate as well as the grain nutrient accumulation. Beans cv. “Ouro Negro” was cultivated at the Universidade Federal de Viçosa. Treatments consisted of increasing levels of Mo (0, 40, 80 and 120 g ha-1), using ammonium molybdate applied to the leaves 25 days after emergence. The experimental design was a randomized […]

The effect of nitrogen levels on the growth and yield of garlic plants grown from tissue culture and conventional propagation. The trial was conducted at an experimental field of the Plant Science Department/UFLA, Lavras, MG, Brazil. A complete randomized block design in a factorial scheme with four replications was used. Plants originated from two propagation methods-tissue culture and conventional and five levels of nitrogen fertilizer – 0, 35, 70, 105 and 140 kg ha-1 were applied during the treatments. Plant […]

Planting spacings and sowing dates may influence nutrient absorption. Therefore, a field experiment was carried out from 1991 to 1992, at the experimental station of Embrapa/Soil Research National Center, located in Senador Canedo, Goiás, Brazil, to determine the N, P and K uptake levels in the aerial part of sunhemp (Crotalaria juncea), Crotalaria ochroleuca, black velvet bean (Mucuna aterrima) and pigeonpea cv. Kaki (Cajanus cajan), under three sowing times (beginning, middle and end of the growing season) and two spacings […]

Three series of experiments were carried out. In the first, the effects of N, Mo, and rhizobium were studied at two municipalities; in the second, conducted at another municipality, a factorial with four rates of N (0, 30, 60, and 90 kg ha-1) and four rates of Mo (0, 40, 80, and 120 g ha-1) was studied; and in the third, at six municipalities, the following combinations of N at planting time (kg ha-1), N as side dressing (kg ha-1) […]

Two axial experiments were carried out in two soils of the Northeast of Brazil from 1987 to 1992 to study the response of coconut to urea, simple superphosphate and potassium chloride. Nitrogen was found to affect the number of fruit in the Quartz Sand Soil. The critical level for nitrogen in leaf 14 was 17.18 g kg-1 which was reached when 1.538 kg of N was applied per plant/year. In the same soil, simple superphosphate did not influence the number of fruit while […]

Two field experiments were conducted on a dystrophic Dark Red Latosol (Haplortox) to study the effects of lime, cobalt and molybdenum on chlorophyll contents in the leaves of peanut. Seed treatments (cobalt, molybdenum, cobalt + molybdenum and no treatment) were applied in two peanut cultivars (“Tatu” and “Tupã”) grown in four rates of lime (0, 4, 6 and 8 t ha-1), causing an increase in leaf chlorophyll contents either due to Mo or lime application. Chlorophyll contents in the leaves […]

The aim of this work was to study the influence of residues of five Sorghum bicolor L. (cv CMS XS 376, CMS XS 365, BR 304, BR 700 and CMS XS 755) on soybean growth. These residues were harvested in three different stages during the sorghum cycle (blooming, milking and physiological maturity) and either spread on the soil surface or totally incorporated in soil, in the proportion of 4 g kg-1 of dry matter in the soil (a Dark Red […]

With the objective of evaluating the effect of exclusive supply of ammonium or nitrate, or both, on the growth of eucalypt seedlings, two experiments were carried out under greenhouse conditions. Eucalyptus urophylla and E. camaldulensis were cultivated in the first experiment and Eucalyptus pellita, E. grandis and E. cloeziana in the second. Initial growth (32 days) was carried out on washed sand bed. Then the seedlings were transferred to nutrient solution with three ammonium/nitrate ratios (100-0, 50-50 e 0-100%) where […]

The effects of soil preparation systems and doses of nitrogen on total dry matter, straw and grain production and on nitrogen accumulation by corn plants (Zea mays L.) cultivated under irrigation were evaluated in a field experiment in a Dark-Red Latosol (Oxisol), originally under cerrado vegetation, at EMBRAPA/CNPMS experimental station, Sete Lagoas, Minas Gerais State, Brazil, from November, 1995 to June, 1996. The soil preparation systems studied were: no till, conventional till with disk plow and conventional till with moldboard […]