Seletividade dos herbicidas Bentazon e Nicosulfuron para Crotalaria juncea e Crotalaria spectabilis em consórcio com a cultura do milho

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Desenvolvimento in vitro e criopreservação de sementes de orquídeas

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Criopreservación de semen bovino de la cola del epididimo utilizando los métodos convencional y automatizado

Cryopreservation of sperm is important to preserve the germplasm from animals of genetic value, which can die unexpectedly. This study compares conventional and automated methods of cryopreservation of spermatozoa obtained from the epididymis of bulls post-mortem. Twenty-two epididymides were obtained from a commercial slaughterhouse. Spermatozoa were collected from the tail of the epididymis using the retrograde flow technique. Thus, the samples, which were diluted in 10 ml of extender without glycerol (Botubov® I, Botupharma, Botucatu, SP, Brazil), were evaluated on motility, sperm vigor, structural and functional (swelling hypoosmotic test) membrane integrity, mitochondrial activity, sperm viability and ADN fragmentation. The samples were divided into two aliquots and diluted in extender with glycerol (Botubov® II, Botupharma, Botucatu, SP, Brazil) at a concentration of 50x106 motile sperm/0.5 French straws. One sample was frozen by the conventional method (4 hours at 5°C, in a refrigerator and 20 min in nitrogen vapor) and the other by the automated method (Cryogen® Dualflex, Neovet, Uberaba, MG, Brazil). The parameters were higher in all the tests of fresh sperm samples, with the exception of the swelling hypoosmotic test, which showed no significant difference when the results were compared with sperm frozen by the conventional method. The average motility of fresh spermatozoa was 74%, and conventional and automated averages were 29 and 25%, respectively. Therefore, although cryopreservation techniques reduce sperm quality parameters, the viability of the sperm is maintained, and these methods can be used to preserve sperm.

Poda apical para produção de frutos e sementes de abóbora

The tip pruning stimulates the emission of lateral shoots, thus can produce higher number of flowers, fruits and seeds. This work aimed to evaluate the effect of apex pruning on fruit and seed production in pumpkin. The treatments consisted of plants without pruning, with pruning in the sixth, eighth and tenth node of main stem. The experimental design was a randomized block, with six replications. It was studied a line of pumpkin of the Germplasm Bank of the Universidade Estadual Paulista/Faculdade de Ciências Agronômicas. The characteristics evaluated were: number of branches per plant and fruit position in branches of the plant production (number and weight) of fruits per plant, fruit yield, fruit average weight, fruit length and diameter, seed weight per fruit, seed yield and quality (germination test, first count, thousand seed weight, emergence, speed of emergence and accelerated aging). There was a significant difference only for number of secondary branches per plant and thousand seed weight, with larger values for plants that have not been pruned. It was obtained high average of germination (94%) and good fruit (16.9 t ha-1) and seed (148 kg ha-1) yield. The apex pruning does not influence the production of fruits and seeds, as well as the physiological seed quality in pumpkin.

Genetic erosion risk by environmental and antropic factor applied on strategies for Lychnophora ericoides conservation

This study evaluated the genetic erosion risk factors and the strategic points for the conservation of Lychnophora ericoides population in “Paraíso Perdido” farm, Serra da Canastra (20° 37’ 54” S; 46° 19’ 37” W; 833 m height) in São João Batista do Glória City, Minas Gerais State, Brazil. The number of young and adult plants, the soil and the phenology were evaluated in two sample areas of 125 m2. Information about the species utilization was obtained with local informants. Data on the region were obtained through literature review, in loco evaluation, GPS and geo-referenced map. In addition, local use of the plant for mixtures of drug was evaluated. According to the results obtained, the soil of the population is lithic with a weathered portion of frank-sandy texture, very acidic and dystrophic. The population density is 0.16 individuals/m2, 0.078 young/adult plant. The predominant phenophase was fruiting (100% plants) followed by flowering (21.62% plants). The local community uses the leaves of the plant in the form of hydroalcoholic extracts, as anti-inflammatory. Based on the evaluated parameters, the population is at 73% risk of genetic erosion. The detected key points were the development of activities including the participation of the local community for habitat protection as well as germplasm collection, seedlings production and reintroduction, together with environmental education, supervision, and reduction in the propensity for fire.