Marcos Antônio Giovanaz

Produção e qualidade de pêssegos, cv. Jubileu, com uso de fitorreguladores

Effect of plant growth regulators on production and quality of Jubileu peaches This study aimed to evaluate the yield, return of flowering and physico-chemical fruit quality of peaches after using Promalin ® (BA + GA 4+7 ) at different doses and time of application. The experiment was conducted at Agricultural Center of Palma on Pelotas Federal University, Capao do Leao - RS, in 2012. Peach trees of cultivar Jubileu, 13 years old, grafted on Capdeboscq rootstock, at a density of 1.481 plants ha -1 were evaluated. The treatments consisted of: plants without application (control), plants treated with benzyladenine (BA) + gibberellin (GA 4+7 ) at the doses 50 and 100 mg L -1 , applied at 10 and 30 days after full bloom (DAFB) . We evaluated the tree yield, return of flowering and physicochemical quality of fruit. Application of plant growth regulator at 30 DAFB resulted in increase of 6.62 kg per tree and fruits of larger caliber ( > 65 mm), but no significant difference was found between the doses 50 mg L -1 and 100 mg L -1 . Regardless of the doses used in this study, the time of application (30 DAFB) was the main factor for the ef ficiency of the growth regulators in increasing the production per tree, average mass, diameter and pulp firmness of Jubileu peaches . The total number of flowers was reduced with the application of BA + GA 4+7 .

Acetylation of barnyardgrass starch with acetic anhydride under iodine catalysis

Barnyardgrass (Echinochloa crus-galli) is an invasive plant that is difficult to control and is found in abundance as part of the waste of the paddy industry. In this study, barnyardgrass starch was extracted and studied to obtain a novel starch with potential food and non-food applications. We report some of the physicochemical, functional and morphological properties as well as the effect of modifying this starch with acetic anhydride by catalysis with 1, 5 or 10mM of iodine. The extent of the introduction of acetyl groups increased with increasing iodine levels as catalyst. The shape of the granules remained unaltered, but there were low levels of surface corrosion and the overall relative crystallinity decreased. The pasting temperature, enthalpy and other gelatinisation temperatures were reduced by the modification. There was an increase in the viscosity of the pastes, except for the peak viscosity, which was strongly reduced in 10mM iodine.

DENSIDADE DE PLANTIO E PRODUÇÃO DO MARACUJAZEIRO-AZEDO NO SUL DO BRASIL

The aim was to evaluate the effects of different planting densities of passion fruit on fruit yield and quality in the region of Pelotas/Rio Grande do Sul/Brazil. The experiment was carried out during the 2011/2012 vegetative period only with plants of one year, and during the 2012/2013 vegetative period both plants of one and two years were evaluated. The treatments have been established according to the following planting densities (plants ha-1): 1.600 (D1); 2.666 (D2); 3.200 (D3). ). In the D3 treatment, the plants of two years have been thinned in the 2012/2013 period, remaining 1.600 plants. Independently of the period, the treatment with higher planting density, i.e. 3.200 plants ha-1 and plants of one year, showed better yield. Two years old plants showed no difference in yield as well as in the number of fruits ha-1 between the planting densities, and the fruit quality had been influenced neither by planting densities nor by the vegetative period.

Early performance of ‘Kampai’ and ‘Rubimel’ peach on 3 training systems

The aim of this study was to examine the early performance of ‘Kampai’ and ‘Rubimel’ peach on 3 training systems. The study was conducted between 2010 and 2013. Treatments were the training systems ‘Ypsilon’, Central Leader, and Open Center, arranged in a randomized complete block design. Assessed parameters were production per tree, fruit weight, yield, fruit firmness, and soluble solids. The early yield and economic return are greater in Central Leader training system for both cultivars. Besides, training system does not influence fruit quality attributes.

GIBBERELLIC ACID REDUCES FLOWERING AND TIME OF MANUAL THINNING IN ‘MACIEL’ PEACH TREES

The thinning peach fruits is to reduce the load of the plant with the aim to improve the size, flavor and color of the remaining fruits. However, the practice of thinning requires high demand of manpower and become more expensive the production costs. The objective of this study was to evaluate the reduction of flowering buds and the time of hand thinning in ‘Maciel’ peach after gibberellic acid (GA3) application at different times and concentrations. The experiments were performed in the harvests of 2012 and 2013 in a commercial peach orchard located in the county of Morro Redondo, RS. The plants of cultivar Maciel, in 2012, were sprayed with four doses of GA3 0, 25, 75 and 125 mg L-1, at different times 20, 40 and 60 days after full bloom (DAFB). The number of flowering buds and consequently thenumber of flowers was reduced in the 2013 season after application of GA3 on the 2012 harvest. The manual thinning decreased with doses applied at 60 DAFB. The number of flowering buds and consequently the number of flowers was reduced in 2013. There was reduction of manual thinning when applied at 60 DAFB. The doses of 25, 75 and 125 mg L-1 applied at 60 DAFB resulted in a reduction of 50.1, 76.9 and 87.1%, respectively, at the time of hand thinning. When applied the dose of 25 mg L-1 of GA at 60 DAFB reduces the number of flowering buds and hand thinning time in the next cycle in ‘Maciel’ peach, without compromising production.