Germinação in vitro e aclimatização de Hamatocactus setispinus

Abstract

Seed propagation preserves the population genetic variability and helps selecting desirable features. This study evaluated the in vitro germination of Hamatocactus setispinus in six different culture media, 1-MS basal medium full strength; 2-halfstrength MS basal medium; 3-1.0 g L -1 of Peter's CalMag ® 15-05-15 formulation; 4-0.5 g L -1 of Peter's CalMag ® 15-05-15 formulation; 5-MS basal medium supplemented with 10% coconut water and; 6-water and agar, with and without activated charcoal, and the speed of germination index, the mean germination time and the germination rate, root length, shoot length and the number of roots were evaluate. The seedlings with superior development obtained from in vitro germination were acclimatized in two substrates: Biomix ® Floreira; Biomix ® Floreira + sand. Seedling survival, shoot length, shoot diameter, root length, root number, shoot fresh matter weight, root fresh matter weight, shoot dry matter weight and root dry matter weight were evaluated. Peter's 1.0 g L -1 medium without activated charcoal led to the best results for root length (11.36 mm) and root number (3.84). There was 100% of seedling survival. Acclimatization substrates did not differ among themselves and, therefore, they did not affect seedling growth. Keywords: Hamatocactus setispinus, activated charcoal, culture media, cacti. RESUMOGerminação in vitro e aclimatização de Hamatocactus setispinus A propagação de sementes preserva a variabilidade genética da população e ajuda a selecionar características desejáveis. Objetivou-se estudar a germinação in vitro de Hamatocactus setispinus em seis diferentes meios de cultura, 1-meio de cultivo MS; 2-MS ½ força de sais minerais; 3-1 g L -1 da formulação 15-05-15 Peter's ® CalMag; 4-0,5 g L -1 da formulação 15-05-15 Peter's ® CalMag; 5-MS com adição de 10% de água de coco e; 6-água e ágar, com e sem carvão ativado, avaliando o índice de velocidade de germinação, o tempo médio de germinação e a taxa de germinação, comprimento da raiz, comprimento da parte aérea e o número de raízes. As plântulas com desenvolvimento superior obtidas da germinação in vitro foram aclimatizadas em dois substratos: Biomix ® Floreira; Biomix ® Floreira + areia. Foram avaliados: sobrevivência de plântulas, comprimento da parte aérea, diâmetro da parte aérea, comprimento da raiz, número de raízes, matéria fresca da parte aérea, matéria fresca da raiz, matéria seca da parte aérea e matéria seca da raiz. O meio Peter's 1,0 g L -1 sem carvão ativado levou a melhores resultados no comprimento de raiz (11,36 mm) e número de raízes (3,84). Houve 100% de sobrevivência das mudas. Os substratos de aclimatação não diferiram entre si e, por isso não afetaram o crescimento das mudas. Palavras-chave: Hamatocactus setispinus, carvão ativado, meio de cultura, cacto.(1) Received in 15/08/2013 and approved in 10/06/2015.

Seed traits and germination in the Cactaceae family: A review across Americas

“…In vitro propagation. Although in a great number of cactus species high percentages of germination have been found (Zimmer 1969b, Meiado et al 2016, various studies have explored in vitro germination as an alternative of propagation (Salas-Cruz et al 2011, Xavier & Jasmim 2015, López-Escamilla et al 2016, Cortés-Olmos et al 2018, Ramírez-González et al 2019. Studies of this type have been performed on more than 40 cactus species (Table 1), with good results in germination and later seedling growth.…”

Micropropagation of Opuntia and Other Cacti Species Through Axillary Shoot Proliferation: A Comprehensive Review

“…micropropagation. A higher concentration of activated charcoal, that is, 3 g/L, was used for the in vitro germination and shoot development of Hamatocactus setispinus (Xavier and Jasmim, 2015). A lower concentration of activated charcoal was used for pitaya cultures.…”