This research evaluated the effects of biosolid levels on yield and chemical composition of Mentha piperita L. essential oil. Mint plants were grown in a greenhouse in pots containing the equivalent to 0, 28, 56, and 112 t.ha-1 biosolid. Three evaluations were made at 90, 110, and 120 days after planting (DAP). The oil was extracted from the dry matter of shoots by hydrodistillation, and composition was determined by GC/MS. Oil production was slightly affected by the biosolid, increasing when plants were grown with 28 t.ha-1, a condition which did not result in quality improvement. Menthyl acetate was the component obtained at the highest percentage in all treatments. At 90 DAP, plants showed a higher percentage of menthol, the second-highest oil constituent, with a content of 42.3% in plants grown without biosolid. The presence of biosolid favored menthofuran formation. As with menthol, menthone decreased with plant development. Under these conditions, plant harvesting is recommended at 90 DAP, period in which the menthol level was higher. Since the production of biosolid is on the rise, a suitable destination must be given to it, and restrictions exist for its use in relation to the environment and plants. Thus, although cultivation with 28 t.ha-1 is within the limits allowed by law, such a rate, which increased oil yield, did not improve oil quality. Therefore, biosolid from the Barueri Station is not recommended for cultivation of this specie.

ResumoO trabalho objetivou verifi car o efeito de reguladores no crescimento de plantas de soja (Glycine max (L.) Merrill cv. BRS-184) e conteúdo de clorofi la. Em experimento instalado em casa-de-vegetação, plantas de soja (Glycine max (L.) Merrill cv. BRS-184) foram cultivadas em vasos de 10L, com terra da camada arável corrigida e adubada conforme a análise do solo. , os quais foram aplicados três vezes a intervalos de 30 dias e realizadas seis avaliações a intervalos de 13 dias. Os resultados revelaram que a maior produção de massa seca total ocorreu com a aplicação de IBA, Stimulate e cloreto de mepiquat. A área foliar foi inferior à testemunha na maioria dos tratamentos; o teor de clorofi la e a taxa de crescimento foram pouco infl uenciados pelos tratamentos. O tratamento com citocinina isolada ou associada a outros reguladores manteve por mais tempo o teor de clorofi la. A TCR e a TAL foram reduzidas a partir dos 99 dias após a semeadura com aplicação de cloreto de mepiquat. Unitermos: Glycine max, retardantes de crescimento, auxina, citocinina AbstractGrowth analysis of soybean plants treated with plant growth regulators. This work aimed to verify the effect of plant growth regulators on soybean plant growth and chlorophyll content. In an experiment carried out in a greenhouse, soybean plants were cultivated (Glycine max (L.) Merrill cv. BRS-184) in 10-liter pots containing soil from the arable layer, corrected and fertilized according to the soil analysis. The treatments used were: control; GA 3 100mg.L . Treatments were applied three times at 30-day intervals. Six samplings were taken at 13-day intervals. The results indicated that the highest total dry weight value resulted from the application of IBA and Stimulate, and that the application of mepiquat chloride in association with IBA and BAP reduced total dry matter production. The leaf area was smaller than the control in most treatments. The chlorophyll content and growth rate were slightly infl uenced by the treatments. The cytokinin treatment alone or in association with other plant growth regulators retained Biotemas, 21 (3): 53-63, setembro de 2008

ABSTRACT

RESUMO -Com o objetivo de avaliar os efeitos de diferentes manejos de palhada de capimbraquiária sobre o desenvolvimento inicial da cultura de soja e da planta daninha amendoim-bravo, foi conduzido um experimento em condições de casa de vegetação no NuPAM-FCA/UNESP, Botucatu-SP. Os tratamentos utilizados foram: manejo da palhada na superfície do solo + irrigação superficial (T1); manejo da palhada na superfície do solo + irrigação subsuperficial (T2); palhada incorporada ao solo (T3); e testemunha sem cobertura (T4). A palhada foi colhida no campo 30 dias após dessecação com o herbicida glyphosate (1,44 g i.a. ha -1 ). O delineamento experimental utilizado foi o inteiramente casualizado, com sete repetições, sendo as unidades experimentais vasos plásticos, com a soja e o amendoimbravo semeados paralelamente, em linhas distintas. O T1 reduziu significativamente o índice de velocidade de germinação (IVG) e a altura das plântulas de soja aos 5 e 10 dias após a emergência (DAE), ao contrário do amendoim-bravo, o qual não sofreu interferência dos tratamentos estudados, constituindo-se em uma planta-problema para sistemas produtivos com palhada de capim-braquiária. Os resultados da análise de crescimento (TCA -taxa de crescimento absoluto, TCR -taxa de crescimento relativo e TAL -taxa de assimilação líquida) das plântulas de soja e amendoim-bravo apresentaram valores máximos aos 15 DAE, com exceção do T3 para soja, o qual reduziu expressivamente o desenvolvimento em relação aos demais tratamentos.Palavras-chave: palhada, plantio direto, planta daninha. ABSTRACT -An experiment was carried out under greenhouse conditions at NuPAM-FCA/UNESP, Botucatu, SP, Brazil to evaluate the effects of different types of straw management of Brachiaria decumbens on the initial development of Glycine max and Euphorbia heterophylla. The treatments were: straw on soil surface + irrigation on the top (T1); straw on soil surface + underirrigation (T2); straw incorporated into the soil (T3) and control (T4

a b s t r a c tOcimum basilicum L. (sweet basil) is an essential oil producing crop used in culinary and fragrance applications. The objective of this controlled environment study was to evaluate the effects of organic and conventional fertilization (applied at two nitrogen rates, 150 and 250 kg N/ha) on plant growth, essential oil yield and chemical profile, and tissue nutrient accumulation in sweet basil. Overall, basil plants fertilized with organic fertilizer at a rate of 150 kg N/ha accumulated greater concentrations of potassium (K) and manganese (Mn). The highest fresh weight was obtained from the plants grown with conventional fertilizer at a rate of 250 kg N/ha. Treatments did not affect the oil content in dried biomass (0.23-0.36% range), oil yields (11.4-20.7 mg/pot), nor the concentration of eucalyptol, (−)-linalool, bornyl acetate, eugenol, ␣-trans-bergamotene, germacrene D, -cadinene and epi-␣-cadinol in basil oil. The results from this study demonstrated that organic or conventional fertilizer can alter fresh or dry weight, and nutrient absorption without modifying essential oil composition.