Vilmar Luciano Mattei

Semeadura direta de canafístula (peltophorum dubium (spreng.)taub. no enriquecimento de capoeiras

This work aimed to evaluate the development of Peltophorum dubium by direct seeding on a succesively cropped field. Seeding was performed in rows of 1.5 m, three meters apart, on September 1977. To protect the seed-spots shelters, bottomless paper and plastic cups were used and wood slates were fixed on them. Seeds were mechanically scarified for 60 seconds. The variables evaluated were emergence, seedling survival, number of seed-spots with plants plant density at one year and plant height at the 18th month. Results at the 9th month showed that the seed-spot shelters contributed for plant establishment in 80% of the seed-spots and in more than 75% of them one year after seeding, when wood slates were used. Direct seeding is a viable alternative for this species which will allow the transformation of shrub areas into an agroforest or even silvipastural system in the near future.

Germination and vigor of Dimorphandra mollis benth. seeds under different temperatures and substrates

The Dimorphandra mollis Benth. - Caesalpiniaceae is a native forest species coming from the Cerrado and Caatinga due to its economical and ecological use, which justifies the studies on seed germination. In this work, germinative performance of D. mollis seeds were studied in different conditions of temperature regime and substrate. The experimental delineation used was completely randomized in factorial 4 x 4 (4 substrates -sand, coconut fiber, vermiculite and paper towel; and 4 temperatures: 25, 30, 35 and 20-30oC), with four replications of 25 seeds each. The following parameters were evaluated: seed moisture content, final germination, first germination count, germination speed index, length and dry matter weight. The best germination and vigor is obtained at 30 and 35oC. The substrates paper towel and vermiculite allow satisfactory germinative performance of seeds, being suitable to evaluate the physiological quality of D. mollis seeds.

Semeadura direta de timbaúva ( Enterolobium contortisiliquum ), canafístula ( Peltophorum dubium ) e cedro ( Cedrela fissilis ) em campos abandonados.

The objective of this work was to evaluate species “timbauva” ( Enterolobium contortisiliquum ), “canafistula” ( Peltophorum dubium ) and “cedro” ( Cedrela fissilis ) in direct sowing, in unproductive areas. Efficiency of shelter utilization at the sowing point was tested and compared to initial vegetation cover management by herbicide application at the sowing point, opposed to manual weeding. Sowing was made in points distanced 1 m in 2.5 m spaced rows. The following variables were evaluated: emergence, survival and number of points with at least one plant, until seven month after sowing. Results allowed to conclude that the native species “timbauva”, “canafistula” and “cedro” have potencial to be used in the direct sowing method in unproductive agricultural areas. Shelter utilization favors initial establishment of “cedro” plants, especially by contributing to lower inicial mortality. Early weed control by a chemical dessecant, at the sowing date, allows for an initial higher plant population of “timbauva” and “cedro”.

Avaliação de diferentes materiais de cobertura e de um protetor físico, no estabelecimento de plantas de Pinus taeda L., por semeadura direta no campo.

This work has had as its objectives to evaluate different covering materials and physical protectors use in the forest population of Pinus taeda L. in direct sowing in the field. Three materials were used: vermiculit, dried and pricked pine needles, peel of rice and reference without covering, with and without physical protector (plastic cup of 300 ml, without botton), with five replications. The sowing was accomplished in the first half of May of 1997, being used three seeds per point. The evaluations done were: emergency at the 60 and 90 days, survival at the 120, 180 and 210 days and population density at the 210 days after sowing. The variance and averages analysis (Duncan 5%), has allowed to conclude that: the vermiculit and pine needles affected beneficially the number of plants emerged in the first 60 days, that is the most critical phase for the future of the forest population of Pinus taeda ; the physical protector, provides the formation of a microenvironment, that guarantees larger percentage in the emergence, survival and initial density of plants of Pinus taeda ; the direct sowing demonstrated to be a viable technique.

Exotic woody plants in Pelotas, Rio Grande do Sul, southernmost Brazil

Exotic species are spreading in various parts of the planet and sometimes becoming biological invaders. A floristic survey was carried out to find exotic trees, shrubs, and climbers in different communities in Pelotas, Rio Grande do Sul, southern Brazil. The traversal method was used at 26 sites. The richness totaled 26 species in 22 genera and 17 families. There are 19 trees, 5 arborescents, 1 shrub, and 1 climber. Most of the exotic species are already naturalized in the study area. Between 1 and 10 individuals sporadically occur at each site. For species of characteristically invasive exotic plants were observed, including 3 trees (Pinus elliottii Engel, Pinus taeda L. Engelm., and Pittosporum undulatum Vent.) and 1 shrub (Ulex europaeus L.). A continuous monitoring of exotic flora is needed to eliminate or control invasive plant species and to avoid economic and ecological damage to ecosystems.

DORMÊNCIA DE SEMENTES E PRODUÇÃO DE MUDAS DE Dimorphandra mollis Benth.

Dimorphandra mollis Benth. is an important native forest species coming from Cerrado and Caatinga due to its economical and ecological use, what justifies the existence of programs of seedling production. This paper aimed to study the efficient methodology to overcome dormancy in seeds and to evaluate, in natural nursery, the effects of distinct substrates and the fertilization on the initial growth of plants. The following treatments applied: T1 - control (seeds whithout scarification); T2 – manual scarification with sandpaper number 50; T3 - immersion in water at 80 and (T4) at 100oC; T5 - boil in water at 100oC for 10, (T6) 30 and (T7) 60 seconds; T8 - chemical scarification with sulfuric acid for 20, (T9) 30 and (T10) 40 minutes. For the seedling production, the experiment was arranged in 4 x 2 factorial, complete randomized design (4 substrates: Tropstrato® pure, and the others: Tropstrato®, coconut fiber and vermiculite with organic compost; without and with fertilization). The best results for overcoming dormancy are obtained with the manual scarification with sandpaper no50 or boil in water at 100oC for 10 seconds. The coconut fiber and the vermiculite with organic compost are good substrates for the seedling production of Dimorphandra mollis .