Cultivo de embriões imaturos de citros em diferentes concentrações de carvão ativado e ácido giberélico

Abstract

RESUMOAdição de carvão ativado e giberelina no meio de cultura podem proporcionar melhores condições no desenvolvimento de embriões imaturos de citros. Objetivou-se avaliar o efeito de carvão ativado e GA 3 (ácido giberélico) no cultivo de embriões imaturos provenientes do cruzamento entre laranjeira Pêra Rio x tangerineira Poncã . Após 118 dias da polinização, frutos imaturos, com 3 a 4 cm de diâmetro, foram coletados, suas sementes removidas e tratadas com álcool (70%) por cinco minutos, hipoclorito de sódio (2%) por 20 minutos e, posteriormente, lavadas três vezes em água destilada e autoclavada. Em condições assépticas, os tegumentos das sementes foram separados, os embriões globulares excisados e inoculados em tubos de ensaio contendo 15 mL do meio MT, acrescido de carvão ativado (0; 0,5; 1; 1,5 e 2 g L . Maior comprimento da parte aérea foi obtido em meio MT, acrescido de 0,1 e 1 mg L -1 de GA 3 , combinado com 2 g L -1 de carvão ativado. Maior comprimento do sistema radicular, massa da matéria fresca e número de folhas de plântulas foram obtidos em meio MT, acrescido de 0,01 mg L -1 de GA 3 , na ausência de carvão ativado. A adição de carvão ativado influenciou na concentração de ácido giberélico acrescido no meio de cultura. Termos para indexação:Citrus sinensis, Citrus reticulata, cultura de embriões. ABSTRACTActivated charcoal and gibberelin provides better conditions on development of citrus immature embryos. Activated charcoal and GA 3 (gibberelic acid) on Pêra Rio sweet orange x Poncã mandarin immature embryos culture was evaluated. After 118 dayspollination, imature fruits with 3 to 4 cm of diameter were collected, seeds removed and treated with alcohol (70%) for five min., sodium hypoclorite (2%) for 20 min. and three times washed with distilled and autoclaved water. In aseptic conditions, the teguments were separated, the globular embryos excised and inoculated in test tubes containing 15 mL of the MT medium culture, added of activated charcoal (0; 0.5; 1; 1.5 and 2 g L -1 ) and GA 3 (0; 0.01; 0.1; 1 and 10 mg L -1 ). After inoculation, the embryos were maintained for 90 days in growth room at 27±1ºC, 16 hours photoperiod and 32 mmol m -2 s -1 irradiance. Higher length of the aerial part was obtained in MT medium added 0.01 and 1 mg L -1 of GA 3 combined with 2 g L -1 of activated charcoal. Higher length of the roots system, fresh mass and number of leaves of seedlings was obtained in MT medium added 0.01 mg L -1 of GA 3 and activated charcoal absence. Addition of activated charcoal influenced in giberellic acid concentration added in MT medium.

In vitro establishment and early development of barueiro (Dipteryx alata Vogel)

“…Given the efficiency of activated carbon to adsorb undesirable compounds, which are occasionally present in the medium, it follows that it also acts on the desirable substances, making them unavailable for the explant, indicating there is a tolerable limit for this agent to the culture medium. The optimal dose in this study was approximately 2,5 g L -1 , a result that corroborates those found by Chagas et al (2005) and Schneiders et al (2012) who worked with Cattleya harrisoniana and several species of citrus, respectively. An adequate supply of activated charcoal is an essential requirement for the satisfactory performance of explants in vitro.…”

“…Several authors have concluded that despite the beneficial effect of activated charcoal, including the absorption of toxic components and medium impurities, it also acts on the useful agents, such as sucrose, salts, and in some cases growth regulators, making them inactive or unavailable for the explant. Thus, they suggest that concentrations between 0.1% and 2.0% are within the desirable range for the safe application of this component (BOULAY, 1964;CHAGAS et al, 2005;GRATTAPAGLIA;MACHADO, 1998;RICCI et al, 2002). Means followed by the same capital letter in a column do not differ by Tukey test at 5% probability; CV: coefficient of variation; LSD: least significant difference.…”

“…In explants of citrus hybrids, activated charcoal favoured positive results in the fresh weight of seedlings; however, the explants began to require higher concentration of GA 3 , a fact that points to interference of the additive in the assimilation of this phytoregulator (CHAGAS et al, 2005). Several authors have concluded that despite the beneficial effect of activated charcoal, including the absorption of toxic components and medium impurities, it also acts on the useful agents, such as sucrose, salts, and in some cases growth regulators, making them inactive or unavailable for the explant.…”

PYROLIGNEOUS LIQUOR EFFECT ON IN AND EX VITRO PRODUTION OF Oeceoclades maculata (Lindl). Lindl.1

“…The often-inhibitory effect on growth, observed for treatments with activated charcoal, may be due to the adsorbent property of activated charcoal so that acting as both growth promoter and inhibitor. This is attributed to an excellent pore network with a great internal surface of the activated charcoal, wherein several culture-medium inhibitory substances or toxic products released by explants can remain adsorbed (CHAGAS et al, 2005;THOMAS, 2008). As a result, this compound adsorbs not only toxic compounds but also essential nutrients to plant growth, which are released slowly (GUSON; MORAES; RONCONI, 2012; VILLA; PASQUAL; SILVA, 2014).…”

Chemical sterilization in in vitro propagation of Arundina bambusifolia Lindl. and Epidendrum ibaguense Kunth

“…The use of activated charcoal in the culture medium, a form of carbon with a high surface area, is known to present elevated capacity to adsorb numerous toxic compounds during in vitro cultivation (Nunes et al, 2008), such as phenolic exudates and excess ethylene produced inside the culture jars (Ribeiro et al, 2000;Chagas et al, 2005;Thomas, 2008).…”