de Menezes Junior F.O.G.,Epagri EE de Ituporanga |
Goncalves P.A.S.,Epagri EE de Ituporanga |
Kurtz C.,Epagri EE de Ituporanga
Horticultura Brasileira | Year: 2013
Biomass production and nutrient uptake on onion (Allium cepa) is influenced by plant nutrition. The experiment was carried out to evaluate biomass production and nutrient uptake of onion under conventional and organic fertilization with the use of biofertilizers. For this purpose we conducted a field experiment in a Cambisol, in 2010, at Ituporanga, Santa Catarina state, Brazil. Four treatments were applied: conventional (T1) (planting application and sidedress with conventional mineral fertilizers and phytosanitary treatment with products recommended for the onion crop), and three others with fertilizer allowed by MAPA (Ministry of Agriculture, Livestock and Food Supply) for organic production systems, differentiated by sidedress application via soil with turkey manure based biofertilizer [Bioperu (T2)] or cattle manure based biofertilizer [Biobovino (T3)] or cattle manure based biofertilizer sprayed at 3% [Biobovino sprayed (T4)]. The cultivar used was Epagri 352-Bola Precoce. The sowing, transplant and harvest were performed in 03/05/10, 12/07/10 and 06/12/2010, respectively. During the cycle were evaluated in days after transplanting (DAT), the total extraction of nutrients from the shoot (at 48, 68 and 108 DAT) and bulbs (148 DAT) and in the same dates of the soil analysis. The growth (fresh biomass) and development (number of leaves) of the plants were measured at 30, 48, 68 and 108 DAT. The addition of nutrients via soil or foliar biofertilizer is not able to supply the needs for nutrients and was responsible for generating imbalances which decrease the growth and development of the crop.
de Menezes Jr. F.O.G.,Epagri EE de Ituporanga |
Neto J.V.,Epagri EE de Ituporanga
Horticultura Brasileira | Year: 2012
The determination of the optimal density of plants per hectare considering species, cultivar, growing region and the system adopted is very important for the economic viability of the vegetable crop activity. We evaluated the effects of five plant densities (200, 250, 300, 400 and 600 thousand plants/ha) in different spatial arrangements on the yield and quality of bulbs of onion cultivar Empasc 355-Juporanga. The experiment was carried out at Epagri, Santa Catarina state, Brazil, from May to December 2010. We evaluated the cycle, productivity, post-harvest losses, crop return and biometric characteristics of the plants. The experimental design was randomized blocks, "split plot" in time, with four replications. The increasing of planting densities had no effect on commercial productivity of bulbs (36.19 t ha-1) and on the productivity of bulbs in classes 3 and above (31.91 t ha-1) and in the conservation of bulbs after three months of storage. However, this procedure resulted in the acceleration of the cycle of the cultivar (about seven days), reduction of the diameter and fresh mass of bulbs and increase of the total yield of bulbs (from 33.58 to 41.92 t ha-1) and yield of bulbs of class 2 (from 0.28 to 10.92 t ha-1). The achievement of higher quality bulbs (class 3) is obtained when using densities between 400,000 and 600,000 plants ha-1. Considering the costs of labor, in transplant and harvest operations, and prices paid to growers, the cost/benefit analysis indicates an increase of US$ 426.53 per hectare in the profitability by using densities of 600,000 plants ha-1.