Sue Ellen Ester Queiroz’s research while affiliated with Instituto Federal Goiano and other places

The direct seeding is presented as an economically viable technique for easy deployment and recovery of degraded areas, however problems in the emergence and early seedling growth are limiting factors for their application. Therefore, this study aimed to evaluate the effectiveness of using physical protector in the emergence and early growth of three tree species, Anadenanthera colubrine, Leucaena leucocephala e Sena pendula. For the protection of the species used were 400 mL plastic cups with the bottom removed, and, within 45 days were examined emergence, survival and seedling height. It was observed that the use of physical protector was not significant for the survival and emergence of the species, but the initial growth of plant height showed the best results with floating seeds when compared to no protection for the species L. leucocephala and A. colubrina. It can be concluded that dismissal is the use of protective emergency and to increase the survival of the species studied, but this is indicated when it is desired to obtain a greater increase in height.

Genipa americana (Rubiaceae) is important for restoration of riparian forest in the Brazilian Cerrado. The objective was to characterize the mechanism and control of germination of G. americana to support uniform seedling production. Morphology and morphometrics of seeds, embryo and endosperm were assessed by light and scanning electron microscopy during germination. Imbibition and germination curves were generated and over the same time interval endosperm digestion and resistance were measured by puncture force analysis and activity assay of endo-β-mannanase (EBM) in water and in abscisic acid (ABA). The gene encoding for EBM was partially cloned and its expression monitored by quantitative real-time-polymerase chain reaction. Embryos displayed growth prior to radicle protrusion. A two-phase increase in EBM activity coincided with the two stages of weakening of the micropylar endosperm. The second stage also coincided with growth of the embryo prior to radicle protrusion. Enzyme activity was initiated in the micropylar endosperm but spread to the lateral endosperm. ABA completely inhibited germination by inhibiting embryo growth, the second stage of weakening and expression of the EBM gene, but EBM activity was not significantly inhibited. This suggests that a specific isoform of the enzyme is involved in endosperm weakening. EBM may cause a general 'softening' of micropylar endosperm cell walls, allowing the embryo to puncture the endosperm as the driving force of the decrease in puncture force.

The X-ray has showed to be a very efficient technique in the quality control of forest tree seeds, characterizing development phases, damages caused by dehydration, improvement and infestation, among others. The aim of this work was to evaluate the physical quality of cedar seeds (Cedrela fissilis) by X-ray test. For this, the cedar seeds were exposed at the following conditions of radiation intensity and times (25 Kv during 60/30 seconds and 30 Kv during 40 seconds) to determine the pattern of X-rays. According to the anatomy visualized by the radiographic image, seeds were classified in Full Seeds; Seeds With Damages, Deformed Seeds and Empty Seeds. Soon after, the seeds were submitted to the germination test, accomplished in BOD, using paper substratum damped in boxes for germination under 25°C and white light. After 20 days, the numbers of normal, abnormal seedlings and died seeds were registered. From the results obtained the intensity of radiation of 25 Kv in the time of exposure of 60 seconds allowed clear visualization of the internal characteristics and damages observed. By the radiographic damage affected the seed germination reducing the plot quality.