Desempenho de genótipos de amoreira-preta em sistema de produção orgânica

Abstract

The objective of the present study was to select blackberry (Rubus spp.) materials adapted to the organic system, belonging to the genetic improvement program of Embrapa Clima Temperado in Pelotas/RS, Brazil. Blackberry genotypes were evaluated through phenology, vegetative development, production aspects and the quality of the fruit, conducted in an organic production system. Evaluations were carried out during two harvests, 2020-2021 and 2021-2022 at Cascata Experimental Station, implemented in 2019. The experiment consisted of eighteen selections: Black 312, Black 331, Black 338, Black 344, Black 347, Black 351, Black 353, Black 356, Black 368, Black 369, Black 373, Black 374, Black 377, Black 378, Black 379, Black 381, Black 384, Black 388 and five cultivars, 'Tupy', 'Xavante', 'BRS Xingu', 'BRS Cainguá' and 'BRS Ticuna'. The plants were grown at 0.8 x 4.0 m spacing, with a trellis system. The experimental design was completely randomized with five plants per genotype. From this, two articles have been developed. Article 1 aimed to characterize the phenological, productive and post-harvest behavior of blackberry genotypes, grown under organic production system in the Pelotas/RS region. Article 2 aimed to show the vegetative, productive and qualitative characteristics of blackberry genotype selections, in order to identify and demonstrate the agronomic profile best adapted to the organic production system. This article contains all the variables analyzed in the first article, plus the genealogy, vegetative vigor and number of thorns in 10 cm of branch. Regarding the phenology, the selections showed earlier behavior than the cultivars in the study. The Black 388, Black 379, Black 369, Black 368, Black 344 and Black 338 selections were the earliest, unlike the Black 384 selection, which was the latest among the genotypes. The productivity among the genotypes varied in both harvests. However, the Black 312 selection presented a higher cumulative production, with approximately 19 kg.ha-1 , showing it to be a genotype adapted to the organic production system. The Black 384 selection and the 'Xavante' cultivar stood out in total soluble solids (TSS) content. The Black 356 selection produced fruits with high acidity and low ratio value, presenting fruits more suitable for the industry. The Black 373 selection produced fruits with high soluble solids content and a balanced SS/AT ratio, producing fruits suitable for fresh consumption. The selections Black 353, Black 368 and Black 381 were concomitantly outstanding in total phenolic compounds, total anthocyanin and total antioxidant activity. From Article 2, it was possible to verify that the selections Black 312 and Black 356 presented superior productive performance compared to commercial cultivars, standing out as the most productive in an organic system. In terms of yield and accumulated production, the Black 377 selection showed superior productive performance to 'Tupy', the most widely planted cultivar in Brazil, with similar productive performance to the Black, 338, Black 347, Black 351, Black 377, Black 353, Black 369, Black 374, and Black 381 selections. The most acidic fruits were obtained with the Black 356 and Black 381 selections. The highest TSS/ATT ratio found occurred in the fruit of selection Black 373. Black 379 and Black 388 selections 7 have been found to have the reassembling habit. It was also found that the Black 381 selection has the highest vegetative vigor, presenting characteristics suitable to serve as a living fence. Thus, the study of different blackberry genotypes under organic production system aims to fill the information deficit about the culture in this system and to help the choice of genetic materials adapted to the soil and climate conditions of the region, enabling technicians and producers to make important decisions about productive factors.