Produção de mudas de dois genótipos de alecrim-de-tabuleiro (Lippia gracilis Schauer) em função de fertilizante mineral, calcário, substratos e recipientes / Seedling production of two "alecrim-de-tabuleiro" (Lippia gracilis Schauer) genotypes under mineral fertilizer, limestone, substrates and containers

Lippia gracilis Schauer popularmente conhecida como alecrim-de-tabuleiro possui moderada atividade antibacteriana, antimicrobiana e antiséptica. Objetivando avaliar o efeito de doses de fertilizante mineral, calcário, substratos e recipientes na produção de mudas de dois genótipos de alecrim-de-tabuleiro realizou-se experimentos com estacas de dois genótipos de L. gracilis. No experimento 1, foram utilizadas estacas apicais distribuídas em bandejas de poliestireno expandido de 128 células com o substrato pó-de-coco + areia (1:1), três repetições e oito estacas por repetição. O delineamento experimental foi em blocos ao acaso, em esquema fatorial 4x2x2, sendo quatro doses do fertilizante (6-24-12+micronutrientes) (1, 2, 3 e 4 g L-1), duas doses de calcário (0 e 1 g L-1) e dois genótipos (LGRA106 e LGRA201). Aos 35 após plantio, foram avaliadas a sobrevivência ( por cento), enraizamento ( por cento), comprimento de raiz (cm) e massa seca de raiz (mg). No experimento 2, foram utilizadas três repetições com oito estacas por repetição. O delineamento experimental foi em blocos ao acaso, em esquema de parcelas subdivididas onde foram testados nas parcelas dois recipientes (bandeja de poliestireno expandido de 128 alvéolos e tubetes de 110 cm³, na sub parcela foram testadas as combinações de quatro substratos (PC - pó de coco; PCA (1:1) - pó de coco + areia (1:1); PCA (2:1) - pó de coco + areia (2:1) e PCA (3:1) - pó de coco + areia (3:1) e dois genótipos (LGRA106 e LGRA201). Aos 35 dias após o plantio foram analisadas as mesmas variáveis do experimento 1, além de altura de parte aérea (cm) e massa seca de parte aérea (mg). A utilização de 1 g L-1 do fertilizante na ausência de calcário foi efetivo para sobrevivência de plantas e enraizamento de estacas de alecrim-de-tabuleiro. Com base nesses experimentos, concluiu-se que o genótipo LGRA106 é superior ao LGRA201 nas variáveis analisadas e recomenda-se a bandeja de poliestireno expandido para produção de mudas de L. gracilis via estaquia.

Commonly known as "alecrim-de-tabuleiro", Lippia gracilis Schauer (Verbenaceae) has moderate antibacterial, antimicrobial and antiseptic activity. This study aimed to evaluate the effect of doses of mineral fertilizer, limestone, substrates and containers on seedling production of two "alecrim-de-tabuleiro" genotypes, using cuttings. In experiment 1, apical cuttings were distributed on expanded polystyrene trays of 128 cells containing coir + sand (1:1), using three replicates of eight cuttings each. Experimental design was in randomized blocks, in a 4x2x2 factorial arrangement, i.e. four doses of fertilizer (6-24-12 + micronutrients) (1, 2, 3 and 4 g L-1), two doses of limestone (0 and 1 g L-1) and two genotypes (LGRA106 and LGRA201). At 35 days after planting, we evaluated survival ( percent), rooting ( percent), root length (cm) and root dry matter (mg). In experiment 2, three replicates of eight cuttings each were used. Experimental design was in randomized blocks, in a split-plot scheme. In the plots, we tested two containers (expanded polystyrene tray of 128 cells and 110 cm³ tubets). In the subplots, we tested four substrate combinations [coir, coir + sand (1:1), coir + sand (2:1) and coir + sand (3:1)] and two genotypes (LGRA106 and LGRA201). At 35 days after planting, the same variables of experiment 1 were evaluated, besides shoot length (cm) and shoot dry matter (mg). The use of 1 g L-1 fertilizer without limestone was effective for plant survival and cutting rooting. Based on these experiments, the genotype LGRA106 is superior to LGRA201 as to the evaluated variables and the expanded polystyrene tray is recommended for the production of L. gracilis seedlings through cuttings.

Subcellular effects of drought stress in Rosmarinus officinalis.

The use of Rosmarinus officinalis, and other wild plant species, in the Mediterranean area is an interesting solution in order to avoid the desertification and rapid soil erosion, because of their good resistance to environmental conditions. Previous articles have described experiments designed to determine the impact of water stress at the plant level in this species, but more knowledge is required at the subcellular and ultrastructural levels. An anatomic and ultrastructural study of the leaves was conducted on Rosmarinus officinalis plants growing under different water treatments. In the leaves of water-stressed plants, the leaf water potential and turgor decreased, and leaf osmotic potential became more negative with respect to control plants. The anatomic investigations showed that both the mesophyll intercellular spaces and the epidermal cell size were reduced significantly under the more intense drought stress conditions. At the subcellular level, chloroplasts accumulated plastoglobuli and lipid bodies, and cuticle thickness was increased under water stress. In our experiment, the anatomic and ultrastructural modifications of Rosmarinus officinalis could be considered an additional adaptation to drought stress together with physiological and biochemical modifications as antioxidant accumulation.

Flower size variation in Rosmarinus officinalis: individuals, populations and habitats.

BACKGROUND AND AIMS: Flowers are relatively invariant organs within species, but quantitative variation often exists among conspecifics. These variations represent the raw material that natural selection can magnify, eventually resulting in morphological divergence and diversification. This paper investigates floral variability in Rosmarinus officinalis, a Mediterranean shrub. METHODS: Nine populations were selected in three major southern Spanish habitats (coast, lowland and mountains) along an elevation gradient. Flower samples from randomly chosen plants were collected from each population, and a total of 641 flowers from 237 shrubs were weighed while still fresh to the nearest 0.1 mg. Leaves from the same plants were also measured. Variations among habitats, sites and plants were explored with general linear model ANOVA. Leaf-flower covariation was also investigated. KEY RESULTS: Most (58%) mass in flowers was accounted for by the corolla, whose linear dimensions correlated directly with flower mass. Averaged over plants, the mass of a flower varied between 12 mg and 38 mg. Habitat, site (within habitat) and shrub identity had significant effects on mass variance. Flowers from the coast were the smallest (17 mg) and those from the mountains the largest (25 mg on average). A pattern of continuously increasing flower size with elevation emerged which was largely uncoupled from the geographical pattern of leaf size variation. CONCLUSIONS: As regards flower size, a great potential to local differentiation exists in Rosmarinus. Observed divergences accord with a regime of large-bodied pollinator selection in the mountains, but also with resource-cost hypotheses on floral evolution that postulate that reduced corollas are advantageous under prevailingly stressful conditions.