A. L. Borges

Produtividade e qualidade de maracujá-amarelo irrigado, adubado com nitrogênio e potássio

Passion fruit is an outstanding tropical fruit and the north region of Minas Gerais State seems suitable for growing it. A study on nitrogen (N) and potassium (K) levels for maximum physical and economic production was carried out in Quartzarenic Neosol of that region aiming to obtain high yields and superior fruit quality of yellow passion fruits. The experiment was implanted in March 1996, with plants spaced 3.5 m x 5.0 m, and irrigated by microsprinkler. The experimental design was a factorial randomized block with five levels of N (0, 100, 200, 400, and 800 kg/ha/year) and K2O (0, 200, 400, 800, and 1600 kg/ha/year), with four replications. From November/1996 to October/1997 it was observed a negative nitrogen effect on fruit number for the fresh fruit market, but no significant effects on fruit quality. On the other hand, potassium had a positive effect on fruit weight and diameter, but a negative one on yield, mainly for doses of 400 kg of N/ha, and no significant one on fruit quality. Considering yield, it is recommended 100 kg of N and 200 kg of K2O/ha/year, for experiment conditions.

Adubação com potássio e nitrogênio em três cíclos de produção da bananeira cv. prata-anã

Nitrogen, after potassium, is the chemical element most required by banana crop. This work evaluated the effect of nitrogen and potassium fertilization on irrigated banana crop (Prata-Ana, AAB) yield. Five rates of N (0 , 200 , 400 , 800 and 1600 kg ha-1 year-1) and five rates of K2O (0; 200; 400; 800 and 1600 kg ha-1 year-1), in a (5x5) factorial design were studied. The data were obtained during three yield cycles (second, third and four cycles), on an eutrofic Red-Yellow latosol, sandy-clay, in the North of Minas Gerais State, Brazil. The content of Mn have increased in the leaves with the increased amount of N applied in the soil. The banana yield reduced with the rise of the Mn content in the leaves, on the second and third cycle. The maximum yield was obtained with the application of 962,5 kg of K2O ha-1year-1, on the fourth cycle. No interaction between N and K was found.

Doses e fontes de nitrogênio em fertirrigação no cultivo do maracujá-amarelo

Passion fruit yield is influenced by several production factors, among them the climate, the soil and the manuring and irrigation practices. Nitrogen (N) is the most absorbed nutrient by the passion-fruit plant and has structural functions in the plant, and it can be supplied by nitric, ammoniacal and starchy sources. The experiment objective was to evaluate nitrogen sources and doses applied in fertirrigation of passion-fruit (Passiflora edulis Sims f. flavicarpa Deg.) production and fruit quality in 17 months of production in a Coastal Tableland Yellow Latosol in Bahia State, Brazil. It was studied, in randomized blocks with split-plots, two sources of N (urea and calcium nitrate), on the plots, and five N doses (0, 100, 200, 400 and 800 kg ha-1), on the split-plots with three replicas. The yellow passion-fruit was planted in a spacing of 3.00 x 1.25 m, in a total area of 1,237.50 m2, and evaluated from january 2000 to january 2002. The results showed maximum yield of 34 ton ha-1, applying 457 kg of N ha-1, in urea form. Nitrogen fertilizer and sources did not interfer in the fruit characteristics and juice quality.

Efeito de doses de NPK sobre os teores de nutrientes nas folhas e no solo, e na produtividade do maracujazeiro amarelo

This work evaluated the effect of nitrogen, phosphorus and potassium fertilization on nutrient levels in the leaves of yellow passion fruit (Passiflora edulis f. flavicarpa Deg.) and on the chemical properties of the soil, in order to maximize yield and optimize fertilizer applications. The experiment was carried out from May/96 to April/98, on a Yellow Latosol, in Cruz das Almas city, State of Bahia, Brazil. It was used a randomized block design, in a fractionated factorial arrangement ½ of 43, with two incompleted blocks. It was evaluated four doses of N (0, 100, 200 and 300 kg ha-1 year-1), of P2O5 (0, 80, 160 and 240 kg ha-1 year-1) and K2O (100, 300, 500 and 700 kg ha-1 year-1). Soil samples and leaves were collected at 12 and 24 months after planting. Yield was evaluated in the first and second production years. Nitrogen fertilization did not affect the N level in the leaves but decreased boron and reduced the soil pH during the second production year. Phosphorus fertilization increased, in average, only 12% of the P levels in the leaves, and 35 times in soil. Potassium fertilization increased nutrient contents in leaves and in soil over the optimum level. Maximum yield of 22 t ha-1, during two years, was obtained with application of 244 kg of N, 72 kg of P2O5 and 285 kg of K2O ha-1.

Teores foliares de nutrientes em genótipos de bananeira

The leaf diagnosis is quite useful for the determination of the nutritional state of plants. The nutritional banana tree demands can differ in accordance with genetic characteristics. The aim of present work was to determinate the macro and micronutrients contents in the third leaf of banana genotypes. Twenty four banana genotypes were selected (triploids and tetraploids), in two production cycles (1999 and 2000), in the Active Germoplasm Bank of Banana at Embrapa Mandioca e Fruticultura Tropical, in Cruz das Almas, Bahia, Brazil. The leaf contents of macronutrients (N, P, K, Ca, Mg and S) and micronutrients (B, Cl, Cu, Fe, Mn and Zn) were determined. The results showed that occurred variation in leaf contents among plants in the same genome group and between the first and second production cycles, with higher medium levels in the second cycle for N, P, Ca, Mg, S, Cu and Mn and lower ones for K, Cl, B, Fe and Zn. The nitrogen contents 21.6 to 28.5 g kg-1 and K 13.7 to 30.8 g kg-1 and they were the macronutrients with the highest contents in the leaves. The chlorine contents was 10.4 to 24.7 g kg-1, manganese 43 to 574 mg kg-1 and iron 56 to 212 mg kg-1,and they were the micronutrients with the highest contents in leaves.

Caracterização física e química de bananas produzidas em sistemas de cultivo convencional e orgânico

The demand for organic fruit grows every year around the world and banana can show growth in this sector both in the domestic and in the foreigner market. However, there is a lack of information that supports the production of organic fruit and that confirms the advantages and disadvantages of the cropping systems. Thus, the purpose of this study was to evaluate bananas from conventional tillage and organic relation to physical aspects. It was used Caipira (AAA), Maravilha (AAAB), Pacovan Ken (AAAB), Prata Ana (AAB), Thap Maeo (AAB) and Tropical (AAAB) cultivars. Organic farming was used in green roof (Canavalia ensiformis and Arachis pintoi) and fertilization with organic compost, rock phosphate, castor bean and wood ashes. In conventional farming it was not used green cover, proceeding only the chemical fertilization with urea (100 kg ha-1), simple superphosphate (280 kg ha-1) and potassium chloride (540 kg ha-1).It was evaluate the physical attributes, number of fruit per bunch, diameter (cm) and fruit length (cm), shell thickness (mm) and chemical attributes, total soluble solids (TSS) pH, total acidity (TTA), humidity (H) and soluble sugar (reducing, non reducing and total). There were no significant differences between organic and conventional crops on these parameters, Tukey test at 5% probability. Virtually there were no differences in the characteristic of banana produced in the organic or traditional systems.

Teores de nutrientes nas folhas de bananeira, cv. Pacovan, sob irrigação

Por meio da analise quimica dos nutrientes na folha, e possivel avaliar o estado nutricional da planta, em que os resultados obtidos sao comparados a padroes que se baseiam na correlacao entre a concentracao do nutriente nas folhas e o desenvolvimento ou producao da cultura. Objetivou-se definir os teores padroes de macro e micronutrientes nas folhas de bananeiras cv. Pacovan sob irrigacao, no polo Petrolina-PE/Juazeiro-BA. Nos bananais selecionados, foram marcadas 20 bananeiras e amostradas as folhas na epoca do florescimento, para analise quimica, e anotado o peso dos cachos de dois ciclos de producao subsequentes. Realizou-se a analise estatistica descritiva, com os dados de plantas com pesos de cachos em quatro estratos ( 10 e 15 e 20 kg), considerando os cachos superiores a 20 kg como em condicoes ideais de nutricao. As faixas dos teores padroes definidas para cv. Pacovan, sob irrigacao, no Distrito de Irrigacao Senador Nilo Coelho, em Petrolina-PE, foram: 22-24 g de N/kg; 1,7-1,9 g de P/kg; 25-28 g de K/kg; 6,3-7,3 g de Ca/kg; 3,13,5 g de Mg/kg; 1,7-1,9 g de S/kg; 13-16 mg de B/kg; 6-7 mg de Cu/kg; 71-86 mg de Fe/kg; 315-398 mg de Mn/kg; e 12-14 mg de Zn/kg.

Fitonematoides associados a bananais 'Pacovan' sob condição de cultivo irrigado: relação com a produção

Among the factors that affect the productivity of banana, stand out pests, diseases and inadequate cultural practices. In this context, plant parasitic nematodes have great importance for reducing the efficiency of water and soil nutrients absorption by the roots, causing the plants to fall down near harvest. About 146 nematode species have already been reported associated to banana roots. Nevertheless, only Radopholus similis, several species of the genus Meloidogyne, Helicotylenchus, Pratylenchus and Rotylenchulus cause significant losses in banana plantations. In plantations located in irrigated areas in the municipal districts of Petrolina/PE and Juazeiro/BA, questionnaires were applied to obtain information about the history of the area, including plant nutrition, fertility, cultural practices, incidence of pests and post-harvesting practices. It was observed that 90% of the area belonged to small farmers. The major problems pointed out were: inadequate management, including harvesting and post-harvesting practices, presence of nematodes and strong winds. In this research a survey of the occurrence of plant parasitic nematodes was carried out. Thus, this research aimed to identify the genera of the plant parasitic nematodes found, and to study the relationship between the banana production in the several selected areas with the population of plant parasitic nematodes in the soil and in the banana root system. In each selected area, 20 banana plants were marked and samples of soil and roots were taken. Each sample was composed of four samples of each plant to represent the population of nematodes. The genera of the most abundant nematodes were Helicotylenchus, Meloidogyne and Rotylenchulus. Nevertheless, the production was neither related to the number of farms in each location, nor with the plant parasitic nematode density (Helicotylenchus sp., Meloidogyne sp., Rotylenchulus sp., Pratylenchus sp. and Radopholus similis) associated with the soil or banana roots. It could be inferred that the cultural practices adopted in each location of irrigated banana production had a positive influence on the banana production (weight of bunches) under different plant parasitic nematode populations.

Efeitos das culturas de milho (Zea mays), feijão (Phaseolus vulgaris) e caupi (Vigna unguiculata) na agregação de valor ao cultivo da bananeira 'Terra', em Teolândia, litoral sul da Bahia

Results are presented of a intercropping system of corn (Z. mays), beans (P. vulgaris) and cowpea (V. unguiculata) with plantains (Musa AAB) in Teolandia, South Coast of Bahia region in two successive plantations of these crops, being one simultaneous to the establishment of the plantain and the other right after the first harvest. Plants spacing in double rows were used (4.0 x 2.0 x 3.0 m, 4.0 x 2.0 x 2.6 m and 4.0 x 2.0 x 2.8 m) and were the most efficient space arrangements of intercropping for a longer period of time. Corn, beans or the cowpea, occupied only the rows between the double rows of the plantains, whereas the interrows remained free in order to avoid shading effect of the plantain. The objective of the present work was to evaluate the performance of corn, beans and cowpea crops in addition of values in plantains. Rentability index - RI (total income ÷ costs) for the best treatments, (T9, T6, T8 and T4), reached significant values of 3.36 (T4) up to 6.68 (T9) resulting in positive effects due to technology and fertilizers applied, which allow greater addition of values to the banana crop and, consequently, increase the producers income. A RI of 3.36 and 6.68 means that for each Real (R

Cultivos intercalares e controle de plantas daninhas em plantios de maracujá-amarelo

) invested there was a return of R