Tratamento de sementes no armazenamento e promoção de crescimento de mudas de Parapiptadenia rigida (Benth.) Brenan

Abstract

Parapiptadenia rigida is a forest species that appears in many regions of Brazil, frequently produced in forest nurseries, being the seeds the multiplication form. Usually presents a good germination, however, aspects involving the physiological and health qualities of the lots, still results in lost in the nurseries. In this sense, microorganisms with antagonist characteristics and/or promoters of growth related to many products and coated with polymers, arise as options to improve the growth of the seedlings in the nurseries. This work aimed to evaluate the treatment of Parapiptadenia rigida seeds, for the physiological quality maintenance in the storage and promotion of the seedlings growth in the nursery. The work was split in studies of storage and nursery. In the storage study, the treatments were arranged in completely randomized lineation in trifactorial scheme (4x4x2), represented by storage timing (0, 4, 8, 12 months), products (biological, chemical and witness) and polymers (polymer and witness), with four repetitions. In each time were made evaluations of the germination percentage, vigor tests, seedling length, fresh and dry mass, besides of regular strong and weak seedlings. The nursery studies was subdivided in two experiments: the first using combinations involving Trichoderma sp., polymers and vegetal growth stimulators, and the second involved the use of Bacilus subtilis, polymers and vegetal stimulators. For both of them, the treatments was arranged in completely randomized lineation in trifactorial scheme (3x2x4), represented by fungicide product (biological, chemical e witness), polymers (polymers and witness), micronutrients and biostimulating (micronutrients, biostimulating, micronutrients + biostimulating, witness) with four repetitions. In about 60 to 120 days after the emergency, the height of the plant, the stem diameter, and the number of leaves was evaluated. At the experiment ending was made weighing of the dry mass of the aerial part, root and total, besides the relation dry mass of the root/aerial part. The work results showed that: the treatment of the Parapiptadenia rigida seeds, with Trichoderma sp. is efficient to the physiological quality maintenance during the storage; Parapiptadenia rigida Seedlings have higher growth in the nursery when derived from seeds treated with Trichoderma sp. and polymer; Polymerization of Parapiptadenia rigida seeds is a technique that can be used in the nursery; Treatment of Parapiptadenia rigida seeds with Bacillus subtilis is not effective in maintaining the physiological quality during storage, as well as to promote the growth of seedlings in nursery; The application of micronutrients and biestimulant in Parapiptadenia rigida seeds, does not promote the growth of seedlings in nursery.