Magnésio, cálcio e potássio em sementes e cotilédones de feijoeiros e sua transferência para plantas jovens

Magnesium, calcium and potassium concentration in the seeds and cotyledons of Phaseolus vulgaris L. cv. Carioca and its translocation from the cotyledons to the plant were evaluated. For such an evaluation plants were cultivated during the cotyledons phase and were irrigated with deionized water. Three samplings of cotyledons completely randomized were done and replicated ten times, before its senescence and fall, at 8, 12 and 15 days after the germination of the seeds. Fresh and dry matter of the cotyledons and its magnesium, calcium and potassium content were determinated in every sample. These parameters were also determined in the seeds from the same lot. Potassium concentration was higher than magnesium in both seeds and cotyledons. Calcium presented the lesser concentration both in seeds and cotyledons. These minerals were translocated from the seeds and cotyledons to the young plants. Eight days after germination 59% of the magnesium, 78% of the calcium and 71% of the potassium were translocated to the plants. Fifteen days after germination these percentages were respectivaley 73%, 82% and 91%. Thus, magnesium was the less and potassium was the most translocated mineral at the end of the study.

Eficiência de absorção e utilização de potãssio por plantas de soja em solução nutritiva

A greenhouse experiment was conducted in a factorial design of randomized complete blocks, with three replications, to study plantage response of soybean cultivars on efficiency: update (EAB); conversion (EC) and utilization, as well as utilization index (IU) by soybean cultivars. Four soybean cultivars (IAC 17, IAC 18, IAC 11 e FT 2) were grown in nutrient solutions with either adequate or deficient K levels (0.5 and 1.82 mmol. L-1) and harvested 20, 40 and 60 days after plant emergence (DAPE). The plants were separated in top, median and lower leaves, stems and roots, dried, ground and analyzed for K contents. Regardless of cultivar, in deficient plants K was translocated from the other organs to median leaves, in order to maintain its K contents. This behavior was particularly evident in 'IAC 11' and 'IAC 18'. Well nourished plants showed higher EAB than deficient plants. 'IAC 17' and 'IAC 18' showed higher EAB at either adequate or deficient K. levels. 'FT 2' showed highest EUK in deficient solutions at 40 DAPE (immediately before flowering), and the lowest EUK at 60 DAPE. The utilization index was helpful in determining cultivar plasticity to adapt to K deficiency. The highest plasticity was observed for 'FT 2' at 40 DAPE and for 'IAC 18' at 60 DAPE. K-deficient plants were more efficient in EC, yielding more dry matter for K uptake unit.

Efeito da densidade de plantas de Bracharia decumbens Stapf sobre o crescimento inicial de mudas de Eucalyptus grandis W. Hill ex Maiden

In order to verify the effect of Brachiaria decumbens plant density on the initial growth of Eucalyptus grandis plants, one assay was conducted under semi-controlled conditions of soil fertility and humidity. Dark red Latossol, collected from the arable layer, was used as substrate in 50 liters amianthus cement boxes. One seedling of Eucalyptus was planted in each box. Fifteen days later, seedlings of B. decumbens were transplanted on the same box. The treatments consisted of 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 60, 80, 100, and 120 plants of B. decumbens. The experimental design was the complete randomized design, with 15 treatments and four replicates. The Eucalyptus plants that lived with B. decumbens were evaluated for stem diameter, plant high, leaf area, and dry weight of stem, branches and leaves. B. decumbens plants were evaluated for dry weight of aerial parts. B. decumbens, at the density level of four plants per m 2 and over, reduced of the initial growth of the Eucalyptus plants. B. decumbens reduced on average 27.78% stem diameter, 18.47% plant high, 70.56% leaf number, 63.26% leaf area, and 55.22%, 77.29% and 55.30% of stem, branch and leaf dry weight, respectively. Plant high was not a good parameter to evaluate the B. decumbens interference.

Revisão de plantas Brasileiras com comprovado efeito hipoglicemiante no controle do diabetes mellitus

Plants have been used in the cure of diseases from the origins of the humanity. At present, in Brazil, the use is common because of the difficulty of access of part of the population to medical assistance. It is commonly believed that the medicinal plants of traditional use were already tested and ratified by the long-lasting use by the human species, being considered effective medicines, presenting no collateral effects, not needful, therefore, of evaluation. The miraculous self-medication with medicinal plants goes to the point of substituting therapies in serious diseases such as those of hypoglycemic or anti-diabetic effect. For the test of medicinal plants, it is necessary to consider the material quality to be tested, the plant component used, extraction method, dosage, and the experimental species used. Several plants have already had hypoglycemic effects proven experimentally. The objective of this paper was to accomplish a revision of Brazilian medicinal plants, used popularly, as hypoglycemics that had effects proven in animals and in humans.

Produção de composto orgânico a partir de residuos de plantas medicinais

Extraction of active principles from medicinal plants generates wastes usually discharged. This process does not extract minerals from plant tissues, which may be considered of great value in organic composting. Wastes of 81 medicinal plant species processed at Centroflora/Anidro industry were analyzed for macro and micronutrients, and according to the results, three different ways to elaborate the compost were proposed: a) wastes of medicinal plants with high content of a specific mineral, aiming to fertilize soils where would be cultivated species that need high quantities of that mineral; b) wastes with mineral contents in order to support specific failures on mineral content of a soil; c) wastes of the eleven richest species in each nutrient that should elevate all mineral contents in soil.

Eficiência de extratos de plantas medicinais e aromáticas em atrair a abelha africanizada (Apis mellifera L.) em cultura de abacateiro (Persea americana Mili.)

The objective of the experiment was to test attractive substances for Africanized honey bees, Apis mellifera L., in avocado, Persea americana Mill. Were pulverized extracts of lemon grass (Cympobogon citratus), ocimum (Ocimum sellowii), Lippia alba, orange leaves (Citrus sinensis), eucaliptus leaves (Eucalyptus sp), eugenol and linalol and the frequency of bees on flowers were evaluated. The frequency of honey bees did increase with the application of the extracts falsa melissa, eucaliptus leaves and orange leaves, used as attractants in Quintal variety. The products tested in Eppendorf tubes did not increased the frequency the bees in Quintal and Fortuna varieties.

Efeito da densidade de plantas de Panicum maximum Jacq. sobre o crescimento inicial de Eucalyptus grandis W.Hill ex Maiden

In order to verify the effect of Panicum maximum plant density on the initial growth of Eucalyptus grandis plants, one assay was conducted under semi-controlled conditions of soil fertility and humidity. Dark red Latossol, collected from the arable layer, was used as substrate in 50 liters amianthus cement boxes. One seedling of Eucalyptus was planted in each box. Fifteen days later, seedlings of P. maximum were transplanted on the same box. The treatments consisted of 0, 4, 8, 12, 16 and 20 plants of P. maximum per m 2. The experimental design was the complete randomized design, with six treatments and eight replicates for P. maximum. One hundred and ten and 190 days after transplanting, Eucalyptus plants grown among P. maximum showed an average reduction of 30.80 and 46.55% stem diameter, 25.10 and 22.50 plant high, 40.18 and 31.29% stem dry weight, 61.32 and 54.06% branch dry weight, 53.72 and 51.82% root dry weight, 44.62 and 38.50% leaf dry weight, 22.51 and 23.16 branch number, 20.72 and 19.97% leaf number, and 33.88 and 17.05% leaf area, respectively.

Faixas de controle de plantas daninhas e seus reflexos no crescimento de plantas de eucalipto

Two field trial were conducted in Eucalyptus grandis W. Hill ex Maiden x Eucalyptus urophylla S.T. Blake crops at Três Lagoas, Mato Grosso do Sul State and Brotas, São Paulo State, Brazil, to evaluate the effects of weed control in strip of different width on the Eucalyptus plant growth. The experiments consisted of two groups treatments: group 1 - with constant width control strips being kept during the first 12 months, i.e., at 0, 25, 50, 100, 125 and 150cm on each side of the Eucalyptus row and, group 2: with increasing width control strips being adopted along the experimental period, i.e., at 25 to 150, 25-50-150, 50 to 150, 50-125-150, 100-125-150, 100 tot 150 and 125 to 150 cm on each side of the Eucalyptus row during the first 12 months. At 49 moths after planting it was verified that the Eucalyptus plants that had grown both in the constant and increasing width control strips, equal to or higher than 100 and 50 cm, respectively, showed higher steam diameter, plant height, volume and annual increment average of wood. These results led to the conclusion that the minimum control strip width should be 100 cm on each side of the Eucalyptus row in order to keep the crop free of weed interference.

Das plantas medicinais aos fitofármacos

The plants, since the antiquity, have been a resource within reach of the human being. Along millenniums, the man empirically deepened its knowledge for the improvement in the alimentation and cure conditions of its illnesses, demonstrating a narrow relation between plant use and its own evolution. A lot of people described the herbs utilization like medication form in their records and manuscripts, but many centuries have been passed until the true power of the plants was recognized. The great discoveries of the active plants principles only were possible after technological advances for the isolation and structural elucidation. Several active substances with pharmacological activity, many times indicated by the popular use, were going proved scientifically. Nowadays, the man still seeks solutions for several diseases and health problems and maybe the plants can contribute of more significant way for resolve them.

Interações entre aves frugívoras e plantas em um fragmento de mata atlântica de Minas Gerais

We studied the frugivorous birds and their fruiting plants during two years in a forest fragment in Viçosa, Minas Gerais State, Brazil. Our aim was to identify the importance of birds and plants based on an importance index that comprise both the number of interactions and interaction exclusiveness. Twentynine bird species and 25 plant species were recorded. Small birds (< 100 g) comprised 85% of the interactions, and Chiroxiphia caudata reached the largest importance index (0.296), with 12 interactions, being six exclusive. Among plants, the melastome Miconia cinnamomifolia reached the largest importance index (0.277), interacting with 72.4% (21) of the bird species. This study showed that seed dispersal by small birds couldn't be underestimated because they disperse seeds of many plant species, even in pristine forests. Studies like this are also important to list the main food resources to frugivorous birds that could be used in management plans.

Diversidade florística de plantas vasculares no município de Januária, Minas Gerais, Brasil

The vegetation in north Minas Gerais State is poorly known, and for some authors it is the southern limit of natural occurrence for 'carrasco' and 'caatinga' species. Floristic sampling was made in different areas of Januária municipality, Minas Gerais, including physiognomies of 'carrasco' (tree-shrub 'caatinga'), deciduous forest, 'cerrado', floodable field and riparian vegetation ('vereda'), besides calcicolous vegetation. Six-hundred-eight species in 114 families were found, the five most diverse families were Fabaceae (87 species), Asteraceae (35 species), Euphorbiaceae (28 species), Bignoniaceae (25 species), and Malpighiaceae (21 species). The sampled vegetation included a diversity of vegetation forms. The most diverse areas were the 'carrasco' and the deciduous forest (274 species), secondary vegetation along roads and trails, and pastures (160 species), 'cerrado' (105 species), 'vereda' (98 species), and calcicolous vegetation and riparian vegetation (78 species each). Compared to other floristic surveys performed in northeastern Brazil, even considering only the woody component (tree and shrubs with 323 species), these results highlight the floristic and physiognomic diversity of the studied area. © 2005 Instituto de Ciências Biológicas - UFMG.

Bioatividade de plantas medicinais no controle de Sclerotinia isolado de Stevia rebaudiana (Bert.) Bertoni

The microorganism Sclerotinia was isolated from roots of Stevia rebaudiana (Bert.) Bertoni in plantations in the northwest of Parana and submitted to the cultivation in the presence of extracts and vegetable balsams of Tarragon (Artemisia draconculus), Thyme (Thymus vulgaris), Manjerona (Origanum majorona), Mint citrata (Mintpiperita var. citrata), Purple Basil (Ocimum basilicum L.), Andiroba (Carapa guanensis) and Copaíba (Copaifera reticulata Ducke). The first five oils were extracted by steam drags, after the drying of the vegetable in greenhouse with circulation of air at 45°C. The last two were used in natura. A suspension (100ìl) of fungus previously cultivated, was added to each plate. The results show that after 7 days of incubation the thyme oils 10ìl, purple basil 25ìl, manjerona 25ìl, mint citrata 50ìl, tarragon 50ìl were capable to inhibit the growth of Sclerotinia, while the andiroba oil only reached this result with 200ìl. The copaiba balsam, even in the concentration of 500ìl, was unable to inhibit the growth of the microorganism.

Efeitos da dessecação de plantas de soja no potencial fisiológico e sanitário das sementes

The objective of this paper was to verify the ideal moment of application of desiccants on the soybeans crop, to obtain seeds with maximum physiological and sanitary quality. The cultivar IAC-15 was sowed at the experimental area of FE/UNESP - Campus of Ilha Solteira, located in the district of Selvíria, State of Mato Grosso do Sul (20° 22′S, 51° 22′W at approximately 335 m of altitude). The experimental design was a randomized block, with treatments in a factorial scheme of 3×3 and 4×4 (dessicant x application time), in 1996/97 and 1997/98, respectively. The desiccants applied during the season agricultural year 1996/97 were: paraquat, diquat, paraquat+diquat mix at the doses 400; 300; 200+150 e 400 g a.i.ha -1, respectively. In 1997/98 the same desiccants were used, at the same doses, with additional treatment application of ammonium glufosinate at the dose of 400 g a.i.ha -1. The desiccants were applied three times in 1996/97 and four times in 1997/98 with 5 days intervals starting at the R 6 stage. According to the environmental conditions of this research the best desiccation time was when soybean plants had 80% to 90% of pods with yellow and brown coloration and seeds with 45% to 60% of water content. There were no effects of any of the desiccants tested in the physiological and sanitary potential required for commercialization of the seeds.