ABSTRACT
Embryogenic cultures were initiated from immature Melia azedarach (Meliaceae) zigotic embryos. Explants were induced on Murashige and Skoog (1962) medium with 4.54 microM thidiazuron or 0.45 microM dichlorophenoxyacetic acid. After 6 weeks of culture on induction medium, somatic embryos were categorized in four morphological classes based on the presence of single or fused embryos and if they remained united or not to the original explant; that were evaluated histologically. The somatic embryos of every category were transferred, in groups or individually, on a 1/4 MS medium. Bipolar embryos, the more typically normal ones, had well defined shoot and root apical meristems and produced single plants; subcultured individually their conversion was 28%, and subcultured in groups the conversion declined to 6.8%. Fused embryos subcultured in groups had only a 2.1% conversion and produced plants with fused stems. None conversion rate in the others classes was associated to poorly developed shoot and root meristematic areas or with their absence. The converted plants were acclimatized and transferred, in a mist, to soil, with an independent of the class 95% survival rate.
Subject(s)
Plant Shoots/growth & development , Melia azedarach/growth & development , Melia azedarach/embryology , Meristem/growth & development , Microscopy, Electron, Scanning , Tissue Culture TechniquesABSTRACT
Extratos hexânicos obtidos dos frutos de Melia azedarach foram testados sobre fêmeas ingurgitadas e larvas de Rhipicephalus (Boophilus) microplus. Foram produzidos quatro extratos: um de frutos verdes e três com frutos maduros, sendo um com os frutos imediatamente processados, outro com frutos armazenados por cinco meses e um testado após armazenamento do extrato por 2 (dois) anos a 4ºC. Os testes foram feitos em triplicata, em diluições de 0,25 por cento a 0,0156 por cento. A eficácia dos extratos foi avaliada através da comparação da Reprodução Estimada dos lotes "controle e tratado" para fêmeas, da mortalidade para as larvas, e do cálculo das DL50 e da potência relativa para larvas e fêmeas. O extrato de frutos verdes apresentou uma eficácia variando de 3,6 por cento a 100 por cento para fêmeas, e o de frutos maduros variou de 5,2 por cento a 99,7 por cento. Os dois extratos causaram uma mortalidade de 100 por cento das larvas nas maiores concentrações. O extrato de frutos armazenados apresentou eficácia de 14 por cento a 83 por cento sobre fêmeas, enquanto o extrato armazenado em geladeira apresentou eficácia de 8,4 por cento a 100 por cento e ambos não apresentaram efeito larvicida. Os resultados obtidos demonstram uma superioridade do extrato verde, com uma menor DL50 e potência 1,497 vezes superior ao extrato de frutos maduros.
Hexanic extracts gotten of the fruits of cinamomo (Melia azedarach) were tested on engourged females and larvae of Rhipicephalus (Boophilus) microplus. Four extracts were produced: one of unripe fruits and three of ripe fruits, being one with the fruits immediately processed, another one with fruits stored for five months and one tested after storage of the extract for 2 (two) years at 4ºC. The tests were made in triplicate, in 0.25 percent- 0.0156 percent dilutions. The effectiveness of extracts was evaluated through the comparison of the Reproduction Estimate of the groups "controlled and treated" for females, of mortality for the larvae, and of the calculation of the DL50 and the relative power for larvae and females. The extract of unripe fruits presented the effectiveness varying the 3.6 percent - 100 percent for females, and of ripe fruits it varied of 5.2 percent - 99.7 percent. The two extracts caused a mortality of 100 percent of the larvae in the highest concentrations. The extract of stored fruits presented effectiveness of 14 percent - 83 percent on females, while the extract stored in refrigerator presented effectiveness of 8.4 percent 100 percent and both did not present larvicidal effect. The results demonstrate a superiority of the unripe extract, with a minor DL50 and superior power 1.497 times to the extract of ripe fruits.
Subject(s)
Animals , Melia azedarach , Plant Extracts/pharmacology , Plant Oils/pharmacology , Rhipicephalus/drug effects , Melia azedarach/growth & developmentABSTRACT
In vitro regeneration of shoots from leaf explants of the Paradise tree (Melia azedarach L.) was studied. Three different portions (proximal portion, distal portion and rachis of the leaflets) of three developmental stages (folded, young still expanding and completely expanded) of leaves of 10-15 year old plants of seven genotypes were cultured on Murashige and Skoog (1962) medium (MS) supplemented with 1 mg x l(-1) benzylaminopurine (BAP) + 0.1 mg x l(-1) kinetin (KIN) + 3 mg x l(-1) adenine sulphate (ADS). The rachis of the leaflets of the completely expanded leaves was found to be the most responsive tissue, in most of the genotypes employed. Shoot regeneration occurred in leaf explants of all the genotypes tested. The best genotype for shoot regeneration was clone 4. Rooting was induced on MS medium supplemented with 2.5 mg x l(-1) 3-indolebutyric acid, IBA, (4 days) followed by subculture on MS lacking growth regulators (26 days). Complete plants were transferred to soil.