Procedência da muda de morangueiro e reutilização de substrato de casca de arroz in natura em sistema com recirculação da solução drenada

Abstract

Substrate preparation with materials available in nearby regions and their reuse, together with the plant cultivation for two cycles or more are techniques widely used in strawberry cultivation. The objective of this work was to evaluate the plant performance from different origins (Spanish, Argentine and national), the reuse of substrates based on raw rice husk for the San Andreas strawberry cultivation in a closed system and the rooting effect on the growth and fruit production. The study was conducted in a greenhouse at the Federal University of Pelotas, RS, Brazil. From the experiments carried out, three articles were composed. Articles 1 and 2 aimed to verify the effects of adding a commercial substrate based on raw rice husk against the use of this pure one. In article 1 plants from three sources were kept for two years in the substrates, and the results for each production cycle were presented. Spanish plants showed higher early and total production in the first cycle. In the second, Argentinian plants matched Spanish ones for fruit production. National plants showed lower results in both production cycles. The plant maintenance in the second production cycle favored the anticipation of the harvest. As for the substrates, both showed improvements in their physical characteristics throughout the experiment. However, the substrate with the addition of conditioner favored growth and fruit production. Article 2 focuses on the evaluation of substrate reuse. Two experiments were carried out in successive years, studying the substrate reuse for up to three and four years of use, respectively, with the seedling replacement annually. The results indicate that both substrates reuse promoted improvements in physical properties until the third year of use, which led to progressive gains in growth and fruit production of the plants until the fourth year of use. The conditioner addition intensified the beneficial changes in the substrate from the first to the fourth year of use, with positive effects on the plants. With the increase in the reuses number, cultivation in raw rice husk substrate provided fruit production like that obtained in the substrate with conditioner. Article 3 addresses the commercial rooting effect on root and shoot growth, as well as the plants fruit production from the same three indicated provenances. The rooting agent favored root growth, causing greater shoot growth and production, in addition to favoring the harvest anticipation. Spanish plants showed better growth and productive performance, followed by national seedlings. Those from Argentine origin showed lower results, due to late planting. Although there is a difference in growth and yields between the plants from the three origins, planting them together on the property favors the harvest distribution. The commercial substrate addition and the reuse of substrates based on raw rice husk improves the substrate physical characteristics and promotes growth and fruit production.