Produtividade de minicepas e enraizamento de miniestacas de clones de erva-mate (<i>Ilex paraguariensis</i> A. St.-Hil.)

Abstract

O objetivo deste trabalho foi avaliar o efeito de épocas do ano e de clones na produtividade das minicepas e no enraizamento de miniestacas de erva-mate (Ilex paraguariensis A. St. - Hil.) tratadas ou não com ácido indolbutírico (AIB). Com esta finalidade, nas quatro épocas do ano realizou-se a coleta de brotos das minicepas de quatro clones de erva-mate, sendo que em cada coleta foi avaliada a porcentagem de sobrevivência das minicepas e o número de miniestacas. Posteriormente, os brotos foram seccionados em miniestacas de gema única, as quais foram ou não tratadas com 2000 mg L-1 de AIB. Aos 30 e 60 dias foram avaliadas as porcentagens de sobrevivência, enraizamento e calogênese, número e comprimento das raízes. As minicepas dos quatro clones de erva-mate apresentaram alta sobrevivência, além de produção constante de miniestacas dos clones 06SM17, 06SM12 e 06SM15 durante as quatro épocas do ano. O tratamento com AIB não incrementou no enraizamento das miniestacas de erva-mate. O processo rizogênico das miniestacas variou conforme o genótipo e a sazonalidade. O clone 06SM15 apresentou a maior capacidade rizogênica nas quatro épocas do ano. As melhores porcentagens de enraizamento foram verificadas nas épocas do outono e/ou inverno para os quatro genótipos avaliados.

Growth and Physiological Responses of Yerba Mate Seedlings and Mini-Cuttings Under Drought Stress

“…The highest proportion of propagules for yerba mate plantations are seedlings, produced by conventional nursery methods. However, given the low seed germination of the species and the need to increase the availability of selected material, the use of propagules obtained by asexual or vegetative propagation techniques known as mini-cuttings is being gradually adopted by farmers (Stuepp et al, 2017;Sá et al, 2018;Pimentel et al, 2019). Nevertheless, for mini-cuttings, the development of an adventitious roots system is critical and different from the seedlings ones (De Oliveira et al, 2019), being able among other factors, to affect the water absorption and consequently the response to water stress situation.…”

Vegetative propagation of mate from shoot cuttings induced by coppicing of selected plants

“…They were coppiced to approximately 20 cm from the soil in January 2017. Successive collections of epicormic shoots were conducted in May 2017, November 2017, February 2018, and May 2018, to study the effect of the seasonality described by Pimentel et al (2019). Adventitious rooting experiments were conducted in a greenhouse at the Center of Plant Breeding and Vegetative Propagation at UFSM, Santa Maria, Rio Grande do Sul, Brazil.…”

“…Mate presents low multiplication rate due to its recalcitrant behavior of cuttings rooting (Bitencourt, Zuffellato-Ribas, Wendling, & Koehler, 2009), which has restricted the mass production of plantlets of these species. The development of adventitious roots is a complex process which may be affected by multiple factors, including the stock plant (Geiss, Gutierrez, & Bellini, 2009;Bisognin, Lencina, Luz, Fleig, & Gazzana, 2018), collection time of vegetative propagules (Pimentel et al, 2019), phytohormones (Bisognin et al, 2018), and cutting diameter (Stuepp, Wendling, Xavier, & Zuffellato-Ribas, 2018).…”

“…For easy rooting species, the collection time may be less important, while in certain species the rooting process can occur only in a specific time of the year (Zem, Weiser, Zuffellato-Ribas, & Radomski, 2015). For mate, it is known that collection time affects the number of sprouts formed after coppicing (Stuepp, Bitencourt, Wendling, Koehler, & Zuffellato-Ribas, 2016), and in the adventitious rooting competence of mini-cuttings (Pimentel et al, 2019). However, the collection time effects in the adventitious rooting competence of cuttings from epicormic shoots induced by coppicing is still not known.…”

Selection between and within half-sibling progenies of Ilex paraguariensis for adventitious rooting of mini-cuttings

“…Since mini-cuttings is a highly feasible technique for vegetative propagation of native tree species, especially when propagules are produced in mini-stumps of seedlings or young plantlets, because mini-cuttings are more responsive for adventitious rooting (Dias et al 2012), as shown for mate (Pimentel et al 2019, Pimentel et al 2020, this study aimed to evaluate halfsibling progenies for developing breeding strategies and to select mate clones with adventitious root competence, required for vegetative propagation by mini-cuttings.…”