Noemi Vianna Martins Leão

Métodos para superação da dormência e biometria de frutos e sementes de Parkia nitida Miquel. (Leguminosae - Mimosoideae)

The biometry of fruits and seeds of Parkia nitida was studied, as were the effects of mechanical escarification without (T2) and with (T3) Benomyl fungicide, immersion of seeds in hot water at 80oC (T4) and at 100°C (T5), and immersion in H3SO4 during 10 (T6), 20 (T7), 40 (T8) and 80 (T9) minutes. Treatment effects were evaluated by counting total germinated seeds at 10, 20, 30 and 40 days after sowing. The experiment was established with four replications of 50 seeds, which were sown in vermiculite. The number of fruits per inflorecense varied from one to eight. The length and width of fruits and the number of seeds per fruits ranged from 36.0 to 80.0 cm, 4.6 to 6.5 cm and 17 to 37 seeds, respectively. The length, width and thickness of seeds ranged from 16.1 to 24.0 mm, 8.1 to 14.0 mm and 5.1 to 9.0 mm, respectively. There was a significant interaction between scarification methods and period required for seeds to germinate. Regression analysis was significant for T2, T3, T4, T6 and T8. Germination under T4 was only 10%, but T2 and T3 had satisfactory effects on seed germination (50.0% and 72.5%, respectively). The treatments with H2SO4 were the most efficient, with mean germination of 80.0%, 82.5%, 80.0% and 74,5% for 10, 20, 40 and 80 minutes of immersion, respectively. Germination of seeds subjected to T1 (control) and T5 was lower than 2.5%. It was concluded that seeds of P. nitida have dormancy caused by integument impermeability; it is necessary to treat the seeds to obtain high germination percentage. Treatments using H2SO4 for 20 minutes and mechanical escarification of seed treated with fungicide were the best for breaking dormancy.

Smallholder production of agroforestry germplasm: experiences and lessons from Brazil, Costa Rica, Mexico and Peru.

ABSTRACT Smallholders often cannot obtain the agroforestry germplasm they require. It has been suggested that commercial smallholder production of germplasm could help resolve this problem, while securing benefits such as genetic conservation and income generation. We evaluate four such initiatives. We found that worthwhile income was generated, and we suggest ways that returns could be increased. We also found that the initiatives had contributed to genetic conservation, although we argue that such outcomes may be more elusive for timber trees than for non-destructively harvested tree crops. The four initiatives fell short of the “win-win” ideal of germplasm production, i.e. that of smallholders profiting through sale of livelihood-enhancing germplasm to other smallholders, principally because sales tend to be to industrial or institutional clients rather than to smallholders. We suggest that, for the potential of smallholder germplasm production to be fully evaluated, detailed characterization of farmer demand and willingness to pay for agroforestry germplasm is needed.

MORFOMETRIA, GERMINAÇÃO E SANIDADE DE SEMENTES DE TACHI-PELUDO

The success of environmental recovery projects depends on the physiological and sanitary quality of seeds. In this sense, research on management and seed technology directly contributes to obtaining seedlings. The study aimed to evaluate the morphometry, germination and sanity of seeds of Tachigali guianensis. Seed morphometry was performed by measuring length, width and thickness of 100 seeds. Germination test was performed in a completely randomized design, consisting of two temperatures (25 and 30 °C) and four replicates of 25 seeds each. The presence of fungi on the seeds was monitored during the study. Seeds showed average dimensions and coefficient of variation of 10.69 mm and 10.50%; 5.70 mm and 17.26%; and 1.57 mm and 15.33% for length, width and thickness for length, width and thickness, respectively. Seeds at 25 and 30 °C had germination average of 85 and 88%, respectively; average time was 4.57 and 4.07, respectively, and the germination speed index was 4.95 and 5.53, respectively. The genera of fungus Lasiodiplodia, Penicillium and Aspergillus were found associated with seeds and seedlings. The data analisys showed that there was a high morphometric variation for the seed measuring parameters such as width and thickness. The temperature of 30 °C increased the speed of seed germination and the seeds of T. guianensis should be sanitized to prevent fungi development and damages during germination and seedling formation.

Seed quality evaluation by Tetrazolium staining of Parkia multijuga Benth.

The purpose of this study was to develop a staining pattern through tetrazolium test to evaluate seed viability of Parkia multijuga Benth (fava-arara-tucupi). The seeds were scarified, soaked into water and distilled for 48 hours for tegument removal and then immersed in a 0.05%; 0.1%; and 0.3% tetrazolium solution for 6; 18 and 24 hours at 35°C, in the dark. The evaluation was performed on the basis of stain intensity and aspect of the tissues. Based on color patterns, the seed images were classified in eight viability classes. Those results were compared with the germination test in a laboratory. The treatment in concentration of 0.1% for 6 hours was considered adequate for the specie, considering the adequate staining and time for analysis.

ASPECTOS BIOFÍSICOS DE FRUTOS E SEMENTES E EMERGÊNCIA DE PLÂNTULAS DE SANTOL

Seed biometry is an easily measured variable that may indicate an existence of genetic variation favoring the production seedlings high-quality. The present study aimed to evaluate the morphometry and fresh mass of fruits and seeds and the initial emergence of seedlings from three mother-trees of santol [Sandoricum koetjape (Burm. f.) Merr.]. The fruits were collected in three mother-trees from Belém, Pará State. For the biophysical aspects of fruits and seeds, 50 and 100 samples were ENCICLOPÉDIA BIOSFERA, Centro Científico Conhecer Goiânia, v.14 n.25; p. 2017 146 used, respectively. The emergence of seedlings was carried out on a sand substrate with sawdust, in the ratio of 1:1, consisting of four replicates with 25 seeds. It was observed high variability for fresh fruit mass, the number of seeds per fruit, fresh mass of the number of seeds per fruit and fresh seed mass. The santol mother trees have the potential for seed collection for the production of seedlings.