Cândido Alves da Costa

Fibra de coco e resíduo de algodão para substrato de mudas de tomateiro

A greenhouse experiment was carried out to evaluate fiber mixture of coconut and cotton waste, to produce substrate for tomato seedling production (cultivar Kada Gigante). The experimental design was randomized blocks, four replications, with seven treatments: T1) Commercial Substrate Hortimix®; T2) 0% coconut dry fiber mass (FC)+100% dry mass of cotton waste (RA); T3) 20% (FC)+80% (RA); T4) 40% (FC)+60% (RA); T5) 60% (FC)+40% (RA); T6) 80% (FC)+20% (RA); T7) 100% (FC)+0% (RA). The vigor was evaluated in terms of percentage and index of emergence, stem diameter, seedling height. Increasing the proportion of coconut fiber to cotton waste ratio resulted in an increase of percentage and index of emergence; however, the stem diameter, seedling height, shoot and root fresh and dry mass decreased. The residue of cotton proceeding from the compostage of residues of the textil factory, constitutes in a useful material in the commercial substrate production.

Produção de mudas de tomateiro em substratos contendo fibra de coco e pó de rocha

ABSTRACT Tomato seedlings production using substrates with coconutfiber and rock waste A greenhouse experiment was carried out to evaluate the ratioof coconut fiber and rock waste, in the tomato seedling production(cultivar Kada Gigante), in Montes Claros, Brazil. The experimentaldesign was of randomized complete blocks with four replicates. Thetreatments were composed of a control and six ratios of coconutfiber (FC) and rock waste (RG): T 1 - Commercial SubstrateHortimix ® ; T 2 - 0% FC + 100% RG; T 3 - 20% FC + 80% RG; T 4 -40% FC + 60% RG; T 5 - 60% FC + 40% RG; T 6 - 80% FC + 20%RG; T 7 - 100% FC + 0% RG. The cultivation was done in polystyrenetrays with cells of 3.5 x 3.5 x 5,0 cm. Stem diameter, seedling height,emergency speed index, emergency percentage, root and aerial partof fresh and dry matter were evaluated. In almost all the evaluatedcharacteristics the commercial substrate was better than the substratescontaining coconut fiber and rock waste. Among the substratescontaining coconut fiber and rock waste, the seedlings with bettercharacteristics were obtained with a mixture of approximately 70%of the volume of coconut fiber.

Efeito da adubação sobre a incidência de traça-do-tomateiro e alternaria em plantas de tomate

Avaliou-se o efeito de quatro niveis de adubacao nitrogenada e potassica (NK) na resposta do tomateiro Lycopersicon esculentum, c.v Santa Clara, ao ataque de mancha de alternaria (Alternaria solani), e da traca-do-tomateiro (Tuta absoluta), em casa de vegetacao, em tres diferentes idades da planta. O delineamento experimental foi blocos casualizados com sete repeticoes, no esquema fatorial 3 x 4. Foram avaliados a altura da planta (cm), area foliar (cm2) e o numero de cachos por planta, flores por cacho, flores abortadas por cacho, frutos por cacho, frutos com mancha de alternaria por cacho, frutos atacados por traca-do-tomateiro por cacho, peso dos frutos por planta e minas de traca-de-tomateiro. A maior percentagem de frutos atacados pela traca foi observado em plantas de tomate cultivadas com altas doses de N. Com o aumento do numero de flores ocorreu menor numero de frutos atacados por alternaria. Tanto o ataque de A. solani como o de traca-do-tomateiro foi concentrado em frutos de menor peso, sendo que quanto maior o numero de flores atacadas por A. solani, menor foi o ataque da traca aos frutos. O ataque da traca aos frutos foi maior em plantas de dois meses do que em plantas de quatro meses de idade, sendo o mesmo observado para o numero de minas da traca-do-tomateiro.

Nutritional properties of cherry tomatoes harvested at different times and grown in an organic cropping

The physicochemical characteristics of the cherry tomato cultivated in organic and conventional production systems and harvested at either 30 or 45 days of cropping were evaluated using a randomized, 2x2 factorial design (2 cropping systems x 2 harvesting times) with five repetitions. The parameters analyzed were color, centesimal composition, total energetic value, carotenoids and bioactive amine content. Tomatoes harvested at 30 days had higher total soluble solid (TSS) content when grown conventionally, but when harvested at 45 days, both conventional and organic tomatoes had similar TSS values, probably due to increased N availability in the soil. Organic cherry tomatoes had higher contents of β-carotene, lycopene and bioactive amine. On the other hand, tomatoes from conventional cropping were more alkaline and brighter. In conclusion, organic tomatoes are more nutritious than conventional varieties, and if allowed to ripen for up to 45 days, contain higher levels of TSS, carotenoids and total bioactive amines.

Production and quality of tomato fruits under organic management

Information about the production and quality of tomato cultivars under organic management and the conditions of climate and soil from the north region of Minas Gerais State, Brasil, are scarce. Thus, this research was carried out to evaluate the production and quality of tomato cultivars under organic management, in this region. The treatments consisted of four open pollination tomato cultivars (Chadwick Cherry, Pitanga vermelha, Santa Clara and Santa Cruz Kada) and five hybrid cultivars (Marguerita, Nicolas, Ellen, Magestade and Dominador). The experimental design was of randomized blocks with three replications. The experiment was carried out using organic fertilization in the initial preparation of the area, compost and rock phosphate and sprays with Bordeaux mixture, neem oil and fertilizer. The marketable yield varied from 12.3 t ha -1 to 23.9 t ha -1 . The hybrid Marguerita presented higher marketable production (23.9 t ha -1 ). The cultivars Chadwick Cherry and Pitanga Vermelha reached similar production as most cultivars and larger proportions of marketable and giant fruits, and therefore, better market quality. All the cultivars presented low potassium and manganese levels in foliar tissue suggesting an evaluation after various organic manuring cycles and better nutrition conditions are necessary to permit the comparison of the performance of cultivars in this system.

Intensidade de ataque de tripes, de alternaria e da queima-das-pontas em cultivares de cebola

The intensity of attack of T. tabaci and incidence of Alternaria porri (Ellis) Cif and Botrytis squamosa J.C. Walker in nine onion cultivars [Aurora, Primavera, CNPH 6400, Crioula Alto-Vale, Vale-Ouro (IPA 11), Franciscana (IPA-16), Piraouro, Conquista and Serrana] was evaluated, in an experiment in randomized blocks design, with five replications. Weekly evaluations were done from the transplanting until harvesting date, in ten plants/parcel of the number of T. tabaci on the leaves, the percentage of damaged foliar area from the first expanded leaf up and the presence or absence of injuries caused by A. porri and B. squamosa. The cv. Franciscana was more resistant to the attack of T. tabaci in comparison to the other onion cultivars. There was no significant difference between cvs for A. porri and Botrytis squamosa resistance. T. tabaci and A. porri were influenced positively and negatively by temperature and relative humidity, respectively.

Influência do cultivo em consórcio na produção de fitomassa e óleo essencial de manjericão (Ocimum basilicum L.) e hortelã (Mentha x villosa Huds.)

As plantas medicinais produzem seus principios ativos de acordo com os estimulos do ambiente, por isso a presenca de outras plantas pode comprometer a producao dos metabolicos secundarios. Assim, o presente trabalho teve como objetivo avaliar o efeito do cultivo consorciado sobre a producao de fitomassa e o teor de oleo essencial de manjericao (Ocimum basilicum L.) e hortela (Mentha x villosa Huds.). O experimento foi conduzido na area experimental do Nucleo de Ciencias Agrarias da Universidade Federal de Minas Gerais, Campus Regional de Montes Claros- MG. O delineamento utilizado foi o de blocos casualizados, com doze repeticoes, compreendendo seis tratamentos: manjericao + cenoura, manjericao + alface, manjericao solteiro, hortela + cenoura, hortela + alface e hortela solteira. A producao de fitomassa e oleo essencial da hortela nao foram influenciados pelos tratamentos. Para o manjericao, apenas a massa fresca variou significativamente com os tratamentos.

Nutrição mineral de plantas de maxixe-do-reino

O objetivo desse estudo foi o de caracterizar as limitacoes nutricionais para a producao de materia seca do maxixe-do-reino, Cyclanthera pedata (L.) Schrad. Foram realizados dois cultivos sucessivos, em vasos de 3 dm 3 de solo. O delineamento experimental foi inteiramente casualizado, em treze tratamentos, com tres repeticoes. Os tratamentos foram baseados na tecnica do elemento faltante (em que se omite a calagem e cada um dos macronutrientes e micronutrientes). A producao de materia seca da parte aerea e raiz foi reduzida pela acidez do solo e baixa disponibilidade de macronutrientes, principalmente P, Ca, Mg e S; as plantas foram pouco afetadas pela baixa disponibilidade de micronutrientes.

Fruit production and classification of four cherry tomato genotypes under an organic cropping system

A field experiment was carried out in the Instituto de Ciencias Agrarias of Universidade Federal de Minas Gerais, Montes Claros, MG, Brazil, during the summer of 2008-2009, to evaluate the productive features of cherry tomato genotypes cultivated under different spacing, in an organic cropping system. The experimental design was randomized blocks in a 3x4 factorial scheme with three replications. The experimental plot was made up of four rows (spaced 1.00 m between rows) with thirty two plants each, utilizing the eight central plants for the analysis. The treatments consisted of three genotypes of cherry tomatoes (CH152, CLN1561-A and Carolina) and four spacings between plants (0.40; 0.60; 0.80; 1.00 m). The fruit percentage in the different diameter classes and the commercial fruits yield per plant and hectare were evaluated. The CH152 genotype produced a greater percentage of noncommercial fruit (with diameter less than 20 mm). The greatest percentage of fruit classified with the largest diameters (above 30 mm) was achieved by the CLN1561A genotype. The highest commercial yields of fruit per plant and per area were found in the CLN1561A genotype, pointing it out as a promising genotype for an organic crop in the summer in the north of Minas Gerais

Productivity of determinate growth tomato lines tolerant to heat under the organic system

The objective of the present work was to evaluate the productive response of heat tolerant lines of determinate growth tomato under the organic production system. The experiment was carried out in the Instituto de Ciencias Agrarias of UFMG, Montes Claros, Minas Gerais state, Brazil. The experimental design was of randomized complete blocks with eight treatments and four replications. The treatments consisted of eight heat tolerant processing type tomato lines obtained from the Asian Vegetable Research and Development Center (AVRDC), China: CLN1621L, CLN1621F, CLN1621E, CLN1466P, CLN2026E, CLN2026D, CLN2026C and CLN2001C. There was an inverse relationship between the average weight of the fruits and the number of fruits per plant. The highest average fruit weight of some lines was compensated by the lowest quantity of fruits, in such a way that there were no significant differences among the lines. Symptoms of nutritional deficiency and incidences of pests and diseases were not verified in any of the studied lines. All lines presented potential for genetic improvement research and cultivation using organic production systems under higher temperature conditions.