Análise comparativa de tubetes biodegradáveis e de polietileno na produção de mudas de Paratecoma peroba (Record & Mell) Kuhlm

• Autor(a) principal: Dias, Bruna Anair Souto
• Data de Publicação: 2011
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/567
• topic: Plântulas; Qualidade de mudas; Substrato; Seedlings; Quality seedlings; Substratum; CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::SILVICULTURA

Seedlings quality is a decisive factor for plantation forest establishment. Producing seedlings in quantity and quality to meet the great demand of the forestry sector is a challenge. Thus, there is a growing search for innovations in the production process that will provide cost reduction of production and obtaining seedlings of good quality standard. One of the factors that influence the seedlings production is the container. Currently, plastic tubes (polyethylene) containers are commonly used in commercial scale for production of forest seedlings, but there are some disadvantages that can be solved using tubes that can be planted with seedlings in the soil, such as biodegradable tubes. However, these new products must be tested to prove the efficiency and to justify the use. In this context, this study aimed to evaluate the technical and economic feasibility of using biodegradable and polyethylene tubes in the production and quality of Paratecoma peroba seedlings (Record & Mell) Kuhlm., and its behavior after planting in the field. For technical feasibility study, the experiment was carried out in nursery and field and installed in randomized blocks, arranged in 4 x 2 factorial scheme, corresponding to four types of tubes, biodegradable tubes of 43 cm3 (TB 43) and 60 cm3 (TB 60), polyethylene tubes of 50 cm3 (TP 50) and 90 cm3 (TP 90), and two substrate compositions, 100% commercial (S1) and 90% commercial plus 10% of subsoil (S2) with five replications. In the nursery, at 90 days after sowing, morphological characteristics of seedlings were evaluated (height H, collar diameter CD, shoot dry matter SDM, root dry matter - RDM, and number of leaves - NL) and Dickson quality index (DQI). In the field at the time of seedlings planting, as well as at 30, 60, 90, and 120 days after planting, growth (H, CD, and NL) and seedlings survival evaluations were made. To study the economic viability, the costs of materials and operations of all production steps of Paratecoma peroba seedlings were counted in the nursery, using the four studied tubes in technical analysis. In the field during seedlings planting, the deployment cost was counted. For both, costs from TB and TP use were compared. The nursery seedlings quality was influenced by the tube volume and the used substrate, and in general the best values of H, CD, SDM, RDM, DQI, and NL were obtained in seedlings production by TP 90 filled with S1, followed by seedlings production by TB 60, TP 50, and TB 43. The seedlings survival in the field was on average 100% for all tested treatments, concluding the planted seedlings had a good quality standard. The seedlings growth after planting was influenced significantly (p≤ 0.05) by tube type in all evaluations and the best results were H, CD, and NL obtained with TP 90 and TB 60 use, followed by TP 50 and TB 43. The cost of seedlings production was influenced by the used tube type, whose unit value was (in Brazilian currency, Real R) R$ 0.343, R$ 0.344, R$ 0.353, and R$ 0.4205, respectively, to those produced in TB 43, 60 TB, TP 50, and TP 90. The total cost of planted seedling was R$ 1.758 R$ 1.764, R$ 1.813, and R$ 1.884, respectively, for those from TB 43, TB 60, TP 50, and TP 90. The use of biodegradable and polyethylene tubes in Paratecoma peroba seedlings produces seedlings of good standard quality and consequent growth and survive post-planting and therefore can be considered technically and economically viable. However, it is noteworthy that, for the use of biodegradable tubes in the seedlings production and forestry plantations on a commercial scale, it is prudent other studies, such as evaluating the growth and development of plants over the years, the time of decomposition of biodegradable tubes in soil and root system architecture of plants.