ABSTRACT Fusarium is the main disease of black pepper (Piper nigrum L.) in Brazil, and grafting using resistant rootstocks can be a sustainable management strategy. Several wild Piper species have been considered resistant to infection. However, further studies on the grafting process are needed to generate a safe technical recommendation for farmers. This research was carried out with the objective of evaluating the initial compatibility of grafting through the interaction between two techniques (top cleft and side cleft) and six rootstocks. The P. nigrum ‘Bragantina’ was grafted onto four wild Piper species (Piper aduncum Link, Piper tuberculatum Jacq., Piper marginatum Jacq., and Piper hispidum Kunth) and two black pepper cultivars (‘Kottanadan Broto Branco’ and ‘Bragantina’-homograft). P. tuberculatum and P. marginatum were incompatible with P. nigrum ‘Bragantina’ in the two grafting techniques. There was total suppression of leaf development with incompatible rootstocks inside cleft grafting. The wild rootstocks had twice as many shoots at the base of the seedling than the cultivars in the top cleft grafting. Side cleft grafting was able to suppress by half the shoots at the base of the rootstock, while the aerial part was maintained. Top cleft grafting provided greater survival, shooting, and leaf emission, which was more evident when using P. aduncum species as rootstock, reaching practically twice the shooting (59.3%) in comparison with the side grafting (30.6%). Therefore, the top method and the use of P. aduncum as rootstock for the production of grafted black pepper seedlings is recommended.

Resumo: O objetivo deste trabalho foi avaliar o efeito de tipos de mudas e idades da planta para a indução floral no desempenho do abacaxizeiro 'Vitória' (Ananas comosus). O experimento foi realizado de abril de 2015 a dezembro de 2016, com mudas de duas classificações diferentes (filhotes com 100 a 200 g e rebentão com 201 a 300 g). A indução floral artificial foi feita no oitavo, no décimo e no décimo-segundo mês após o plantio, e a indução natural também foi avaliada. Realizaram-se avaliações quanto ao desenvolvimento vegetativo, à fenologia e à produtividade. Observou-se interação significativa entre os fatores estudados quanto à largura e à área da folha “D”. O tipo de muda não influenciou a produtividade. O florescimento natural estendeu o ciclo da cultura em 617 dias. A indução realizada no oitavo mês antecipou a colheita em até 167 dias. Induções mais precoces reduziram a produtividade em 58,15%, em razão da redução da massa dos frutos. Plantas induzidas naturalmente produziram frutos maiores, que variaram de 1,0 a 1,2 kg. As induções do oitavo ao décimo mês possibilitam colheitas em épocas mais favoráveis.

Abstract: The objective of this work was to evaluate the effect of shoot types and plant ages for floral induction on the performance of 'Vitória' pineapple (Ananas comosus). The experiment was carried out from April 2015 to December 2016, using shoots of two different classifications (slips of 100 to 200 g and suckers of 201 to 300 g). Artificial floral induction was performed at the eighth, tenth, and twelfth months after planting, and natural induction was also evaluated. Evaluations for vegetative development, phenology, and productivity were performed. A significant interaction was observed between the studied factors for width and area of the “D” leaf. Shoot type did not influence productivity. Natural flowering extended the crop cycle by 617 days. The induction performed at the eighth month anticipated harvest by up to 167 days. Earlier inductions reduced productivity by 58.15% due to the reduction of fruit mass. Naturally induced plants produced larger fruit ranging from 1.0 to 1.2 kg. Inductions from the eighth to the tenth month promote harvesting in more favorable seasons.