Alexandre Gonçalves Galvão

Yield of tomato fruits in relation to silicon sources and rates

There is controversy about the benefits of silicon (Si) on tomato plants. This element has structural and metabolic functions in the physiology of plants, generating benefits that may result in increased productivity of various plant species. Thus, the aim of this study was to evaluate the phytotechnical characteristics and the productivity of tomato plants according to the rates and sources of Si. The design was established in randomized blocks with factorial 3x5, corresponding to three sources of silicate (calcium silicate, potassium silicate and sodium silicate) and five doses of Si (equivalent to 0, 100, 200, 400 and 800 kg ha-1 of SiO2). The fertilization with Si increased the commercial productivity of tomato plants and reduced the occurrence of cracked fruits. Calcium and potassium silicates increased the Si levels on the leaves linearly with the increase of the doses, while sodium silicate reduced the levels in larger doses. Silicon fertilization increases the productivity of tomato plants with possible economic return on the use of this input.

Tomato yield and soil chemical attributes depending on previous cover crops

The influence of different cover crops was evaluated over the agronomic performance of tomato hybrids for industrial processing, as well as its effect over soil chemical attributes. The experimental design was completely randomized, in a split plot scheme, with four replications. Main treatments (plots) were composed of winter cover crops (oat, hairy vetch, clover and radish) and of a fallow area (spontaneous vegetation). Subplots were composed of four processing tomato hybrids (AP529, AP533, Katia and Sicilio). We evaluated the total production (TP), marketable production (CP), average mass of marketable fruits (AMCF) and number of marketable fruits (NCF). Chemical analysis of soil was done in two stages: one week preceding implantation of cover crops and in the phase of tomato implantation. Highest TPs were obtained in treatments in which cover crops were composed by hairy vetch and radish. However, although hairy vetch has caused an increase in TP, no difference between covers was obtained in relation to CP. Sicilio hybrid presented the greatest AMCF, however, its TP was lower than expected. This fact is related to lower NCF, which was half of the observed in AP529 and AP533 hybrids. Radish cover increased phosphorus, calcium and potassium in soil and this could be one of the factors responsible for the increase of TP provided by radish. On the other hand, oat has caused inverse effect, reducing availability of Ca and K. All covers have increased organic matter in soil, the major increment being presented by oat. Based on these results we conclude that hairy vetch and radish are the most indicated plants for cover preceding tomato cultivation.

Caracterização morfológica, produtividade e rendimento comercial de cultivares de alho

Brazil could increase garlic production up to the point of supplying the internal demand. To achieve this success, it is necessary to evaluate the maximum number of cultivars to establish the best ones for each region. Therefore, we aimed to evaluate economic yield and quality of bulbs of 20 garlic cultivars in Center-South Parana state, Brazil. The experiment was carried out between March and September 2009, in Guarapuava, Parana state. Experimental design was randomized blocks with three replications. The treatments consisted of twelve seminoble and eight noble garlic cultivars. We evaluated the total production (TP), commercial production (CP) and commercial classification of bulbs; secondary bulb growth; and six characteristics related to the plant morphology: pseudostem diameter, length and leaf width, length, width and number of cloves. Noble group cultivars have presented TP superior to seminoble cultivars. However, there was no difference in relation to CP. Among cultivars of noble group, San Valentim presented greater CP bulbs, with 8,9 t ha-1. Noble group cultivars have presented higher percentual of bulbs in classes 6 and 7, especially the cultivars Chonan, with 40.3% of the bulbs in the class 7 and cultivar Ito, with 75% of the bulbs in classes 6 and 7. The opposite was observed in the seminoble group, since most bulbs of this group were found in classes 3, 4 and 5. Among the evaluated cultivars, San Valentin showed to be better adapted to the edafoclimatic conditions of the region, presenting a great yielding potential.

Overcoming strawberry achene dormancy for improved seedling production in breeding programs

espanolLos aquenios de la fresa presentan latencia del tegumento. Este hecho, unido a la baja eficiencia de la polinizacion artificial implica en la realizacion de un mayor numero de cruzamientos para asegurar el numero minimo de aquenios utilizados en la produccion de plantulas en programas de mejoramiento. El objetivo de este estudio fue el de probar soluciones quimicas para superar la latencia en aquenios de la fresa con el fin de aumentar la germinacion y el indice de velocidad de germinacion (IVG). Este estudio consistio en dos experimentos. 1) Inmersion en H2SO4 (98%), HCl (37%) y NaClO (2%) para los tiempos de 0 (control), 10, 20, 35 y 50 minutos. 2) los aquenios se sumergieron en H2SO4 (98%) para los tiempos de 0 (control), 20, 25, 30, 35 y 40 minutos. Se utilizo un diseno completamente al azar (DCA) con cuatro repeticiones. La germinacion y el IVG fueron evaluados todos los dias durante 15 dias. La escarificacion con H2SO4 (98%) durante 40 min aumenta la germinacion de los aquenios de la fresa a 80% y puede ser utilizado como una tecnica para superar la latencia. La escarificacion con HCl y NaClO aumenta la germinacion y el IVG, sin embargo, debe estudiarse junto a otras concentraciones y tiempos de inmersion de esos metodos. EnglishStrawberry achenes present tegument dormancy. This fact, together with the low efficiency of artificial pollination requires a larger number of crossings to ensure the minimum number of achenes used in seedling production in breeding programs. The aim of this study was to test chemical solutions to overcome dormancy in strawberry achenes in order to increase the germination and Germination Speed Index (GSI). The study consisted of two experiments. 1) immersion in H2SO4 (98%), HCl (37%) and NaClO (2%) for 0 (control), 10, 20, 35 and 50 min were evaluated. 2) achenes were immersed in H2SO4 (98%) for 0 (control), 20, 25, 30, 35 and 40 min. A completely randomized design with four replications was used. Germination and GSI were assessed daily for 15 days. Scarification with H2SO4 (98%) for 40 min increased strawberry achene germination to 80% and can be used as a technique to overcome dormancy. Scarification with HCl and NaClO increases germination and the GSI, however, other concentrations and immersion times of those methods should be studied.