AGROCHEMICALS AND STEM CUTTING TYPES FOR PLANTLET PRODUCTION OF Spondias sp

Portuguese. RESUMO A umbu-cajazeira (Spondias sp.), frutífera nativa do Nordeste brasileiro, produz frutos muito valorizados pelas agroindústrias. O objetivo deste trabalho foi avaliar a aplicação de agroquímicos e lesões no enraizamento e na formação de mudas/estacas, foi conduzido na Embrapa em Pacajus, CE, em blocos ao acaso, com cinco tratamentos: T1 = testemunha, T2 = estacas feridas + Sela Gel®, T3 = estacas feridas + Radimax®, T4 = estacas incisadas + Sela Gel® e T5 = estacas incisadas + Radimax®. Os ambientes (blocos): pleno sol; teto com plena sombra; sombrite 50% nas laterais e no teto; e sombrite 50% no teto. As parcelas tinham oito estacas, totalizando 160 estacas. Dos propágulos retirados de plantas, preparam-se estacas lenhosas, com 25 cm de comprimento e médias de 29,7 mm de diâmetro e 8,7 gemas/estaca. Em seguida foram tratadas com solução de hipoclorito de sódio a 0,05%/4 minutos; depois fez-se os ferimentos e as incisões e aplicou-se o Sela Gel® por pincelamento e o Radimax® por imersão em solução de 10 mL/L d'água/10 minutos. O plantio foi em vasos plásticos pretos, com capacidade 6L, cheios com vermiculita + pó de cascas de coco + bagana de carnaúba triturada + cascas de arroz carbonizada (2:1:1:1, v/v), previamente pasteurizados. Entre os tratamentos e os blocos houve diferenças significativas. A incisão e a aplicação do Sela Gel® induziram a formação de calo, o enraizamento e a formação de mudas vigorosas, enquanto o Radimax® não induziu o enraizamento.

English. ABSTRACT Umbu-caja (Spondias sp.) is a fruit tree native to the Northeast region of Brazil, which is grown because of its highly valuable fruits for fruit processing industries. The objective of this work was to evaluate the effect of agrochemical applications and cutting types on the rooting and development of Spondias sp. plantlets. The experiment was conducted at the experimental field of the Embrapa Tropical Agroindustry, in Pacajus, CE, Brazil. A randomize block experimental design was used, with five treatments - control (T1); cuttings with two lesions at the base (CL) + rooting gel (RG) (Sela Gel®) (T2); CL + rooting fertilizer (RF) (Radimax®) (T3); cuttings with two transversal cross sections at the base (CS) + RG (T4); and CS + RF (T5). The environments (blocks) used were: full sun; 100% shade ceiling; 50% shade walls and ceiling; and 50% shade ceiling. The plots consisted of eight cuttings, totaling 160 cuttings. Propagules were taken from Spondias sp. plants to make woody cuttings with length of 25 cm, diameter of 29.7 mm, and mean bud per cutting of 8.7. All cuttings were immediately treated with a 0.05% sodium hypochlorite solution for four minutes before making the lesions and transversal cross sections and applying the treatments. The RG was applied by brushstroke, and the RF was applied by immersion in an aqueous solution of 10 mL L-1 for 10 minutes. The cuttings were planted into 6-liter black plastic pots filled with a pasteurized mixture of vermiculite, coconut husk powder, ground leaf fibers of Copernicia prunifera, and carbonized rice husk (2:1:1:1; v v-1). The treatments and blocks significantly affected the rooting and development of cuttings. The treatment with CS and application of the RG (T4) promoted root callus formation, rooting, and vigorous development of plantlets, whereas the RF (T3 and T5) failed to promote root formation.