ABSTRACT The aim of this study was to select pear cultivars with production stability for the environmental conditions in the tropics. The design was in randomized blocks with 11 cultivars of pear, four replications and plots consisting of four plants. Between 2015 and 2019, the phenological were evaluated based on the beginning, full bloom, end and duration of flowering and harvest. The number and average fruit mass, yield per plant and estimated yield were also quantified. In the last year of evaluation, the quality of the fruits was quantified through the length and average diameter of the fruits, total titratable acidity, total soluble solids content and total soluble solids / total titratable acidity ratio. The data were submitted to the Scott–Knott grouping test and to quantify the divergence between cultivars was used the genetic distance. After detecting significant interaction between genotypes × environments, phenotypic stability of pear cultivars were analyzed by GGE Biplot methods for the estimated yield variable. The ‘Tenra’, ‘Triunfo’ and ‘Seleta’ cultivars are the most suitable for cultivation in regions with subtropical altitude climate. They are genetically similar, more adapted and stable, and have full or partial synchronized flowering for satisfactory productivity.

Abstract The objective of this work was to determine the genetic diversity, yield, and fruit quality of persimmon genotypes grown in the tropics, in order to select promising genetic materials. DNA extraction was performed on young leaves of 19 persimmon genotypes. For pomological characterization, 15 genotypes were selected. From each genotype, 50 fruit at the physiological maturity stage were harvested in the morning, in order to determine the following parameters: physicochemical characteristics; and the productive variables number of fruit per plant, average fruit fresh mass, average yield, and estimated average yield in two seasons. Twenty SSR markers were tested, out of which 12 were selected to evaluate genetic similarity, which allowed of the identification of distinct groups. The mean genetic diversity value found was 0.41, which is an indicative of low diversity among the analyzed persimmon genotypes. The 'Guiombo', 'Iapar 125', 'Kakimel', 'Mikado RJ', 'Rama Forte Tardio', and 'Taubaté' genotypes show a high yield. The genotypes classified as pollination-constant astringent ('Pomelo', 'Regina', 'Rubi', and 'Taubaté') and those classified as pollination-variant astringent ('Rama Forte', 'Guiombo', and 'Cereja') are potential materials for selection and genetic breeding programs due to their excellent fruit physicochemical characteristics. The investigation through molecular markers is an efficient approach to study the genetic diversity of persimmon genotypes grown in the tropics.

Resumo O objetivo deste trabalho foi estimar a diversidade genética, o rendimento e a qualidade de frutos de genótipos de caquizeiros cultivados nos trópicos, para selecionar materiais genéticos promissores. A extração de DNA foi realizada em folhas jovens de 19 genótipos de caqui. Para a caracterização pomológica, foram selecionados 15 genótipos. Para cada genótipo, 50 frutos foram colhidos pela manhã, no estágio de maturidade fisiológica, para determinar os seguintes parâmetros: características físico-químicas; e as variáveis produtivas número de frutos por planta, massa de matéria fresca média dos frutos, produtividade média e produtividade média estimada, em duas safras. Vinte marcadores SSR foram testados, dos quais 12 foram selecionados para avaliar a similaridade genética, o que permitiu a identificação de grupos distintos. O valor médio de diversidade genética encontrado foi 0,41, o que é indicativo de baixa diversidade entre os genótipos de caqui analisados. Os genótipos 'Guiombo', 'Iapar 125', 'Kakimel', 'Mikado RJ', 'Rama Forte Tardio' e 'Taubaté' apresentam alta produtividade. Os genótipos classificados como sendo de polinização constante adstringente ('Pomelo', 'Regina', 'Rubi' e 'Taubaté') e os classificados como sendo de polinização variante adstringente ('Rama Forte', 'Guiombo' e 'Cereja') são materiais com potencial para uso em programas de seleção e melhoramento genético, devido às suas excelentes características físico-químicas de fruta. A investigação por meio de marcadores moleculares é uma abordagem eficiente para estudar a diversidade genética de genótipos de caquizeiro cultivados nos trópicos.

ABSTRACT. As the fourth largest importer of olive oil and the fifth largest importer of olives, Brazil is one of the largest importers of olive (Olea europaea L.) products in the world. In recent decades, the introduction and growth of olive cultivars with lower chilling requirements in the south and southeast regions of Brazil have made olive production viable in the country. However, there is a dearth of information about the management of olive crops in Brazil, especially in relation to studies about the nutritional needs of olive trees grown in subtropical regions, which may enable advances in the productivity of this fruit. The aim of this study was to evaluate the growth, dry matter production and nutritional status of the olive tree under the effect of nutrient omissions, as well as to establish visual diagnostic parameters of nutrient deficiencies. We used a completely randomized design with ten treatments and three replicates grown in the Hoagland-Arnon nutrient solution and solutions with individual omissions of N, P, K, Ca, Mg, S, B, Fe, and Zn. The treatments that most limited the growth of olive trees were the N, Ca, and B omission treatments.

ABSTRACT. The present study aimed to review the advances in the production of temperate fruits to determine future research directions that improve production in the tropics. Temperate fruits are no longer only produced in regions characterized by a cold winter period. These fruits are also produced in the sub-tropical and tropical regions characterized by mild winter or even the absence of chilling conditions often required by the tree to break dormancy. Currently, temperate fruit production is possible in certain regions of South America, Africa and Asia that are near to the Equator. However, temperate tree fruit production in tropical regions requires modified techniques to overcome dormancy and allow adequate flowering, growth and productivity. The main approaches taken are the development of cultivars with low chilling requirement, chemical induction of budbreak, interruption of irrigation during the winter period, defoliation, orchard densification, and double pruning. Breeding has become a key tool in the advancement of temperate fruit growing in the tropics, especially with the development of low chilling requirement cultivars.

RESUMO: O cultivo de ameixeira é amplamente difundido nas zonas temperadas. No Brasil, a exploração desta fruteira se estende desde as regiões mais frias do Rio Grande do Sul até o sul de Minas Gerais. No entanto, as cultivares exploradas nas regiões subtropicais são escassas devido a trabalhos de competição. O presente trabalho objetivou-se selecionar cultivares produtivas de ameixas e adaptadas às condições subtropicais brasileiras. Para isso, foram utilizadas as ameixeiras ‘Fla 87-7’, ‘Gema de Ouro’, ‘Grancoure’, ‘Harry Pickstone’, ‘Januária’, ‘Santa Rosa’ e ‘Satsuma’, enxertadas sobre o porta-enxerto ‘Okinawa’ e avaliadas por dois ciclos no município de Lavras, MG. Avaliou-se o desenvolvimento fenológico; atributos físico-químicos das frutas; número médio de frutas por planta; massa média das frutas e produtividade estimada em cada cultivar. Conclui-se que as ameixeiras ‘Januária’ e ‘Grancoure’ são as mais promissoras para regiões subtropicais, principalmente, pelo volume de frutas produzidas e qualidade das frutas.

ABSTRACT: Plum growing is widespread in temperate zones. In Brazil, the exploitation of this fruit tree is extended from the colder regions of the state of Rio Grande do Sul to the south of the state of Minas Gerais. However, cultivars exploited at subtropical regions are scarce due to competition. The present study aimed to select productive cultivars of plums adapted to Brazilian subtropical conditions. In this respect, the plum cultivars ‘Fla 87-7’, ‘Gema de Ouro’, ‘Grancoure’, ‘Harry Pickstone’, ‘Januária’, ‘Santa Rosa’ and ‘Satsuma’ were grafted on the ‘Okinawa’ rootstock ‘and evaluated by two cycles in the municipality of Lavras, MG, Brazil. The phenological development, physical and chemical properties of fruits, average number of fruits per plant, average fruit mass and estimated yield were evaluated for each cultivar. It is concluded that plum cultivars ‘Januária’ and ‘Grancoure’ are the most promising for subtropical regions, mainly due to the volume of produced fruits and the quality of fruits.

O objetivo deste trabalho foi avaliar o efeito da inoculação de fungos micorrízicos arbusculares (Glomus clarum Nicolson e Schenck, Glomus etunicatum Becker e Gerd Gigaspora margarita Becker e Hall e Scutellospora heterogama Nicolson e Gerd) em mudas micropropagadas de mirtileiro da cultivar Woodard. O delineamento experimental utilizado foi o de blocos casualizados, com cinco tratamentos, quatro repetições por tratamento e seis plantas por parcela. As plantas inoculadas com G. margarita apresentaram maior altura e biomassa seca das raízes. Os tratamentos com S. heterogama e G. margarita apresentaram os maiores resultados para a biomassa verde das raízes. O desempenho foi relacionado com as taxas de colonização das raízes que, nas plantas inoculadas com G. margarita e S. heterogama, foram de 48,2 e 45,1%, respectivamente. Para os teores nutricionais, as plantas inoculadas com S. heterogama, G. etunicatum, G. clarum e G. margarita proporcionaram maiores teores de N e P na parte aérea das plantas.

The objective of this study was to measure the effect of inoculation with arbuscular mycorrhizal fungi (Glomus clarum Nicolson and Schenck, Glomus etunicatum Becker and Gerd, Gigaspora margarita Becker and Hall and Scutellospora heterogama Nicolson and Gerd) in seedlings of blueberry cultivars Woodard. The experimental design was a randomized block with five treatments, with four plots per treatment and six plants per plot. Plants inoculated with G. margarita showed greater height and dry weight of roots. The treatments with S. heterogama and G. margarita showed the highest results for the green biomass of roots. The performance was related to the rate of colonization of roots, plants inoculated with G. margarita and S. heterogama, were 48.2 and 45.1%, respectively. For the nutritional contents, plants inoculated with S. heterogama, G. etunicatum, G. clarum and G. margarita provided higher levels of N and P in the shoots.