Search Results (2)

Research Highlights: One of the ways to improve the quality of a seedlot used in the forest nursery is the grading of seed by colour. Background and Objectives: The study is intended for forest’s engineers and owners because it offers an alternative solution for forest seeds improvement before sowing. The success of forest establishment program mainly depends on the quality of Forest Reproductive Material. At this time usual practices during the seed processing is seed grading on size. This causes a lot of controversy about the possible reduction of genetic diversity through directional selection. Materials and Methods: Aiming to study the effect of seed coat colour on seedling performance, a one-year old container seedlings of Pinus sylvestris L. were planted at the post-fire site. Seedlings were produced from three fractions, previously graded in the visible wavelength range on a standard optical separator, plus control obtained without separation by colour. Results: Seedlings from different seed fractions performed differently in the first growing season after planting on the field. Seedlings from light seed fraction grow better in height, but those from dark seed fraction resulted with the highest survival rate. Light-dark seeds, which constitute the largest group in the initial sample by absolute weight, resulted with seedlings of the lowest growth rates and survival. The good results showed by seedlings from the control, for both growth rates and survival, indicate the weak effect of seed colour grading on seedlings field performance, but also the need for the more comprehensive studies in the future. Full article

Research Highlights: Forest owners will be able to solve the problem of testing and selection of viable forest seeds on location and save financial, time, and material resources. The possibility of integrating non-destructive quality control and separation functions in a single portable apparatus is extremely promising. The speed of the contemporary optoelectronic grader is limited by the speed of the slowest component—the mechanical system. Background and Objectives: The technological process of forest seed establishment and design of optoelectronic graders is based on a priori mathematical modeling of structural characteristics, taking into account these criteria. Known models of industrial photoseparators are expensive and have a high energy and material consumption not applicable in the field. Laboratory seed analyzers are characterized by a long time exposure, and the overall size and level of climatic performance do not allow them to be used in the field. Consequently, for small amounts of seed treatment, it is necessary to orient the seeds one by one and ensure clear and rapid coordinated actions of optoelectronic and mechanical systems. The main goal of this research is to increase the efficiency of grading forest seeds by patterning the speed of the mobile device. We will answer the following questions. What are effective geometric parameters for the seed pipe? What factors affect the speed of a single seed’s movement? Materials and Methods: This study is based on mathematical modeling, taking into account the basic principles of mechanics, using MatLab software. Results: A mechanical model of a single Scots pine seed’s motion in different zones of the seed pipe is designed, taking into account air resistance. The effective height of the seed pipe, taking into account the response time of optoelectronic grader systems, is determined. Conclusions: The time and speed of single seed movement through grader systems depends on the seed pipe’s height and radius of curvature. Other things being equal, through the use of the same optical scheme with a microprocessor to solve various problems, the compactness of the photodetector scheme allows, if necessary, to upgrade the grader to solve research problems and for use in forestry. Full article