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Mate (Ilex paraguariensis A. St.-Hil) is an arboreal species of great economic and socio-environmental importance in South American countries. This specie presents several difficulties during seminal propagation, and studies related to plantlet production by vegetative propagation are fundamental for obtaining homogenous mate plantations with high leaf productivity. Therefore, the present study aimed to evaluate the effects of substrate and shading levels on the morphophysiological quality of mate plantlets produced by mini-cuttings. Rooted mini-cuttings of four mate clones were cultivated on commercial substrate, subsurface soil and vermiculite (2:1:1 v/v/v), commercial substrate and subsurface soil (2:1 v/v) or subsurface soil, cattle manure and carbonized rice hulls (2:1:1 v/v/v). After 120 days, the plantlets were randomly distributed on benches to evaluate the effects of 50 and 80% shading screens. Regardless of the clone, the commercial substrate and subsurface soil composition allowed plantlet production with satisfactory development of both aerial part and root system at 120 days of cultivation. Clone 06SM17 produced plantlets with high averages of stem diameter, shoot height, number of leaves, total length, surface area, total volume of roots, and number of root tips. Both shade levels resulted in similar stem diameters, shoot heights, numbers of leaves, and a, b, and total chlorophyll indices. Clonal mate plantlets with satisfactory morphophysiological quality are produced in commercial substrate and subsurface soil (2:1 v/v) under 50 and 80% shading.

The aim of this work was to evaluate the in vitro productivity of grapia (Apuleia leiocarpa) micro-stumps cultivated in different media conditions to maximize its multiplication rate. Micro-stumps from aseptic seedlings were cultivated in WPM medium added with 0, 2.2, 4.4, 6.6 and 8.8 µM of 6-benzylaminopurine (BAP) and subcultured in WPM medium without cytokinin. Micro-stumps were also cultivated in WPM, MS or ½ MS base media with or without the addition of 1.5 g L-1 of activated charcoal and submitted to drastic pruning at 30, 60 and 90 days of cultivation. The in vitro cultivation of grapia micro-stumps in WPM or ½ MS media added with 8.8 µM of BAP and the subcultivation in media without cytokinin increase the number and length of shoots. The cultivation of grapia micro-stumps in media with activated charcoal increases the productivity of micro-cuttings per micro-stumps, but in the absence of activated charcoal induces callus formation and indirect organogenesis of shoots. The in vitro conservation of grapia microstumps maximizes the multiplication rate, being a feasible technique for the production of grapia plantlets.

ABSTRACT: This study aimed to evaluate the rooting capability of apical and nodal mini-cuttings of ipe-roxo ( Handroanthus heptaphyllus ) in different substrates. Shoots produced from mini-stumps were fractioned into mini-cuttings 2-cm long apical or nodal mini-cuttings and treated with 1000 mg L-1 of indolebutyric acid (IBA). Four substrate combinations were evaluated: commercial substrate composed of pine bark and vermiculite in proportions of 1:1, 2:1 and 1:2 (v /v) and commercial substrate, vermiculite and sand in the proportion of 1:1:1 (v/v). The factorial experiment utilized a completely random design, with five replicates of four mini-cuttings. Rooting, shooting and survival percentage, number and length of shoots and roots were evaluated at 60 and 90 days of growth. Commercial substrate and vermiculite are a good combination for rooting mini-cuttings of ipe-roxo. Apical and nodal mini-cuttings exhibit similar rooting behavior and both are feasible for production of ipe- roxo plantlets.

O objetivo deste trabalho foi avaliar o estabelecimento e crescimento in vitro de plantas de grápia (Apuleia leiocarpa (Vogel) J. F. Macbr.) em diferentes condições de cultivo. Sementes de grápia tratadas com ácido sulfúrico (H2SO4) por 20min foram imersas em etanol a 70% por 30s e em hipoclorito de sódio (0; 2,5 ou 5,0% de cloro ativo) por 5, 10 ou 15min. Aos 30 dias de cultivo, as sementes foram avaliadas quanto às porcentagens de desinfestação e germinação. As plantas assépticas foram transferidas para os meios de cultura WPM, MS e ½MS e avaliadas quanto ao comprimento (cm) da parte aérea e total das raízes e ao número de segmentos nodais e folhas aos 15 dias. Sementes de grápia também foram semeadas em meio de cultura WPM, suplementado com 4, 5 ou 6g L-1 de agar combinado com 10, 20 ou 30g L-1 de sacarose, e mantidos sob duas condições de luminosidade: luz durante todo o período de estabelecimento e escuro durante sete dias após a semeadura. Foram avaliados a porcentagem de germinação das sementes, o comprimento (cm) da parte aérea e total das raízes e o número de segmentos nodais e folhas aos 15 dias. Concluiu-se que os tratamentos com ácido sulfúrico e etanol foram suficientes para o estabelecimento in vitro de plantas assépticas de grápia. Plantas assépticas podem ser cultivadas em meio de cultura WPM ou MS, suplementados com 10g L-1 de sacarose e 4g L-1 de agar.

This study aimed to evaluate the production of cordia (Cordia trichotoma) ministumps of seminal and asexual origin, as well as the effect of the naphthaleneacetic acid (NAA) on the rooting of mini-cutitings. Seedlings and plantlets from rooted cuttings were pruned to form a clonal mini-hedge. The ministumps were fertirrigated with three concentrations of nutrient solution and they were evaluated for survival and production of mini-cuttings. The mini-cuttings were or not treated with 1000mg L-1 of NAA and planted in substrate for rooting. The mini-cuttings were evaluated for the percentages of survival and rooting, and number and total length of roots after 30 days of cultivation. There was no difference in survival and number of mini-cuttings obtained from seminal or asexual ministumps. Mini-cuttings from ministumps of asexual origin showed higher rooting capability. The use of 1000mg L-1 NAA did not increase the rooting percentage of cordia mini-cuttings.