Elisângela Aparecida da Silva

Efeito de diferentes substratos na produção de mudas de mangabeira (Hancornia speciosa)

The mangabeira (Hancornia speciosa Gomes) is a native fruit species from the Brazilian Cerrado, as trees its fruit characteristics are appreciated by consumers and present expressive production potential. The objective of this study was to evaluate the effect of different substrates on production of mangabeira seedlings in plastic bags and to determine the best substrate for species propagation. The study was conducted in a greenhouse at Mato Grosso do Sul State University, in Cassilândia county, State of Mato Grosso do Sul. The experimental design used was randomized blocks, with four replications and 15 seeds per plot. Five substrates were evaluated: A (washed sand + Plantmax® + soil, 1:1:3 v:v:v), B (carbonized rice husk + Plantmax® + soil, 1:1:3), C (carbonized rice husk + earthworm humus + soil, 1:1:3), D (bovine manure + Plantmax® + soil, 1:1:3) and E (bovine manure + soil, 2:3). The following parameters were evaluated: percentage of germination, velocity of emergence index (VEI), percentage of mortality, seedling height (cm), stem diameter (mm), root length (cm), number of leaves/plant, chlorophyll index (CCI), dry mass of shoot, root and the whole plant (g/plant). The best characteristics for healthy good quality seedlings were obtained with substrates D and E, which are recommended for the production of mangabeira seedlings in plastic bags.

Tipos de enxertia em diferentes idades de plantas de maracujazeiro

The vegetative propagation of passion fruit can provide to obtain uniform seedlings and orchards, with the use of rootstocks with good characteristics such as tolerance to soil-borne diseases. The objective was to study methods of grafting at different ages of passion fruit plants after emergence. The experiment was conducted at the Horticulture Sector, of the Federal University of Lavras (UFLA), in MG, on mesh with 50% shading. The experimental design was randomized blocks in a 2x4 factorial design, two methods of grafting (cleft grafting, splice grafting) and four times in budding (15, 25, 35 and 45 days after emergence). It was evaluated: percentage of grafting success, leaf number, plant height and diameter. It is concluded that the grafting of sour passion fruit on the sweet, both in cleft grafting and splice grafting, the best time to perform is 15 days after emergence, showing an index of grafting success of 98% in both methods.

Eficiência do hidrogel e respostas fisiológicas de mudas de cultivares apirênicas de citros sob défice hídrico

Water is a limiting factor in citrus development which makes hydric replacement a common practice in plantations where its distribution is scarce. The hydroretentor gel has been one of the available technologies for water supply to plants and may also be an alternative that contributes to the rational use of water for planting citrus seedlings. This study evaluated the efficiency of hydrogel as an alternative to minimize the effects of water deficit in seedlings of seedless cultivars of tangerines (‘Ortanique’, ‘Okitsu’ and ‘Clemenules’) and oranges (‘Navelina’, ‘Navelate’ and ‘Lanelate’), all grafted on Poncirus trifoliata . The experiment was carried out in a greenhouse, in a randomized blocks design, where plants with hydrogel were compared to plants under conventional irrigation and also to plants under water deficit, in a triple factorial arrangement. The rates of carbon liquid assimilation, stomatal conductance and transpiration and the ratio between internal and external CO 2 concentrations were evaluated. It was verified that the effect of the hydrogel for maintaining the hydric status of citrus seedlings is variable and dependent on physiological mechanisms of response to water deficit. There was no response of ‘Ortanique’ and ‘Navelate’ seedlings to the hydrogel application. The hydrogel promoted the recovering and maintenance of the hydric status of ‘Okitsu’, ‘Clemenules’, ‘Navelina’ and ‘Lanelate’ seedlings, however, these cultivars were sensitive to changes in the water status, with considerable reduction of gas exchange.