Agroclimatic mapping for olive cultivation in Brazil: pinpointing optimal growing regions.

BACKGROUND: This research aimed to identify the agroclimatic zones in Brazil, excluding Rio Grande do Sul, that are suitable for olive (Olea europaea L.) cultivation, considering both climatic and topographical factors. Olives require specific conditions: moderate winter temperatures (7-15 °C), warmer summers (25-35 °C) and sufficient water during growth and fruit maturation. They can endure some drought, making them a viable option for agricultural diversification. Using daily meteorological data from 1989 to 2023 from NASA-POWER, this study analyzed variables like air temperature (minimum and maximum) and rainfall. Key climate variables were the mean air temperature in winter (T_w), spring (T_s), summer (T_su) and autumn (T_a) and total annual precipitation (Prec). Criteria for suitability included: T_w between 5 and 20 °C, T_s between 15 and 23 °C, T_su between 15 and 30 °C, T_a between 15 and 22 °C, annual precipitation over 900 mm and altitude below 900 m. Geographic information system software and Python 3.8 were employed for data analysis and zoning. RESULTS: Results indicated that only 1.92% of the analyzed area, mainly in Minas Gerais, was suitable for olive cultivation. High temperatures and low rainfall in Brazil, particularly in the North and Midwest, make 59.56% of the country unsuitable for olive farming. Additionally, 18.58% of the land, mainly in the Northeast, faces challenges due to extreme heat (T_w) and insufficient water supply. © 2023 Society of Chemical Industry.

Climate zoning: identifying suitable regions for the occurrence of Alternaria Brown spot in tangerine trees in Brazil.

BACKGROUND: Brazilian citrus farming has been migrating to nontraditional citrus-growing regions, which can be considered a challenge for citrus growers, as not all these areas are suitable for tangerine cultivation. Thus, the mapping of regions exhibiting favorable climatic conditions for Alternaria brown spot has become crucial in the selection of appropriate locations for the establishment of new orchards. This mapping enables the implementation of an avoidance strategy, which entails steering clear of areas where the disease is prevalent, aligning with fundamental principles of disease control. RESULTS: Thus, this study seeks to zone areas with high and low climatic favorability for the occurrence of Alternaria brown spot in tangerine trees in Brazil. Historical climate data series from the NASA-POWER database were used for all municipalities in Brazil. Agrometeorological variables used to determine the development of Alternaria brown spot were average monthly air temperature (Tmean) and duration of leaf wetness period (LWD). Areas were considered unsuitable climatically when Tmean was <17 °C or >33 °C, relatively suitable when Tmean was between 13 °C and 33 °C and LWD <10%, and climatically suitable when Tmean was between 13 °C and 33 °C and LWD >10%. The states of Paraná, Santa Catarina and Rio Grande do Sul showed greater thermal amplitude within months and throughout the year. The southern region of the country has harsher winters, with minimum temperatures below 15 °C, which is unfavorable for the disease incidence. CONCLUSION: The states with the greatest favorability for Alternaria brown spot were Paraná, Santa Catarina, and Rio Grande do Sul, mainly from May to September. Rio Grande do Sul was the state in this region that showed the greatest favorability, as a consequence of leaf wetness exceeding 10 h. The main tangerine-producing regions in Brazil, including the southern part of Minas Gerais, the state of São Paulo and the metropolitan region of Porto Alegre, were mostly classified as relatively favorable areas for the occurrence of Alternaria brown spot. It is recommended that when establishing new tangerine orchards, regions with lower favorability for the occurrence of Alternaria brown spot, such as the North and Central-West regions of Brazil, particularly the states of Amazonas, Pará and Mato Grosso, should be selected. © 2023 Society of Chemical Industry.

Deep Tillage Strategies in Perennial Crop Installation: Structural Changes in Contrasting Soil Classes.

Tillage modifies soil structure, which can be demonstrated by changes in the soil's physical properties, such as penetration resistance (PR) and soil electrical resistivity (ρ). The aim of this study was to evaluate the effect of deep tillage strategies on three morphogenetically contrasting soil classes in the establishment of perennial crops regarding geophysical and physical-hydric properties. The experiment was conducted in the state of Minas Gerais, southeastern Brazil. The tillage practices were evaluated in Typic Dystrustept, Rhodic Hapludult, and Rhodic Hapludox soil classes, and are described as follows: MT­plant hole; CT­furrow; SB­subsoiler; DT­rotary hoe tiller; and DT + calcium (Ca) (additional liming). Analyses of PR and electrical resistivity tomography (ERT) were performed during the growing season and measurements were measured in plant rows of each experimental plot. Undisturbed soil samples were collected for analysis of soil bulk density (Bd) at three soil depths (0−0.20, 0.20−0.40, and 0.40−0.60 m) with morphological evaluation of soil structure (VESS). Tukey's test (p < 0.05) for Bd and VESS and Pearson linear correlation analysis between Bd, ρ, and PR were performed. Soil class and its intrinsic attributes have an influence on the effect of tillage. The greatest effect on soil structure occurred in the treatments DT and DT + Ca that mixed the soil to a depth of 0.60 m. The ρ showed a positive correlation with Bd and with PR, highlighting that ERT may detect changes caused by cultivation practices, although ERT lacks the accuracy of PR. The soil response to different tillage systems and their effects on soil structure were found to be dependent on the soil class.

Selection of plum cultivars for subtropical regions / Seleção de cultivares de ameixeira para regiões subtropicais

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.

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.

Seminiferous propagation in the selection of chestnut tree rootstocks / Propagação seminífera visando a seleção de porta-enxertos para castanheira

ABSTRACT: Aiming the selection of rootstocks to produce seedlings, the objective of this study was to quantify the seminiferous propagation in chestnut seeds, with or without incisions. Nine cultivars were used ('Ibuki', 'Isumo', 'Kinshu', 'Moriwase', 'Okuni', 'Senri', 'Taishowase', 'Tamatsukuri' and 'Tiodowase') and two selections ('KM-1' and 'KM-2') of hybrid chestnut trees (Castanea crenata x Castanea sp.). An incision was held in half of chestnuts and the other half remained intact. Percentage of germination, emergence and root length were quantified. The germinated nuts were transplanted and were quantified the diameter and height of seedlings. Then, the chestnut selections 'KM-2' and 'Jacutinga' were grafted by the cleft grafting method, and were quantified the percentage of sprouting, besides the diameter and height of grafts. Incisions increase the germination and seedling emergence in most cultivars and selections. 'Taishowase' and 'Tamatsukuri' stood out over the others to germination, growth of the rootstocks.

RESUMO: Visando a seleção de porta-enxertos para a produção de mudas, o objetivo do trabalho foi quantificar a propagação seminífera em castanhas com ou sem a realização de incisões. Foram utilizadas nove cultivares ('Ibuki', 'Isumo', 'Kinshu', 'Moriwase', 'Okuni', 'Senri', 'Taishowase', 'Tamatsukuri' e 'Tiodowase') e duas seleções ('KM-1' e 'KM-2') de castanheira híbridas (Castanea crenata x Castanea sp.). Em metade das castanhas, realizou-se uma incisão e a outra metade das castanhas permaneceu intacta. Foram quantificadas a porcentagem de germinação, emergência e o comprimento das raízes. As castanhas germinadas foram transplantadas onde se quantificou o diâmetro e a altura das mudas e ao final, a massa seca da parte aérea. Em seguida foram enxertadas pelo método de garfagem as seleções de castanheira 'KM-2' e 'Jacutinga', se quantificando a porcentagem de brotação, além do diâmetro e altura dos enxertos. Concluiu-se que as incisões aumentam a germinação e a emergência das plântulas, na maioria das cultivares e seleções. 'Taishowase' e 'Tamatsukuri' se destacam em relação as demais quanto a germinação e crescimento dos porta-enxertos.

Cold storage of budsticks/clefts for staggered grafting in persimmon trees / Armazenamento refrigerado de ramos porta-borbulhas/garfos para enxertia escalonada em caquizeiro

ABSTRACT: The persimmon tree is propagated by grafting and the rootstocks are produced from seeds. Grafting is done in July, which coincides with the time when the persimmon trees are pruned. But, at this time, many rootstocks are not yet eligible to receive the grafts. In this case budsticks/cleft storage is an option. Thus, this study aimed to verify the feasibility of cold storage of budsticks/cleft and verify the grafting method to promote better graft development. Rootstock was sown in August 2012 and the branches were collected in July 2013. Part of the branches was used for grafting (budding and cleft graft methods) in one-year old rootstocks and the other part was stored at low temperature (cuttings wrapped in moistened paper and then wrapped in polyethylene bags placed in cold storage at 4°C), during the months of August to December. Every 30 days, a number of branches was removed from the cold storage to perform grafting by budding and cleft and to quantify total sugars and starch in the budsticks/cleft stored. One hundred and twenty days after the grafting was performed, the length and diameter of the bud, number of leaves, sprouting percentage, dry weight of aerial part and root from the grafts were measured. It was concluded that there is no difference in the budding graft for different periods, but in seedlings grafted by the cleft grafting method there is greater growth when the clefts have been in cold storage for 60 to 120 days.

RESUMO: O caquizeiro é propagado por enxertia e os porta-enxertos são produzidos por sementes. A enxertia é realizada em julho, que coincide com a época de poda dos caquizeiros. Porém, nessa época, muitos porta-enxertos ainda não estão aptos a receberem os enxertos. Nesse sentido, o armazenamento dos ramos porta-borbulhas/garfos seria uma opção. Assim, o presente trabalho teve por objetivo de verificar a viabilidade do armazenamento refrigerado dos ramos porta-borbulhas/garfos e diagnosticar o método de enxertia para promover melhor desenvolvimento do enxerto. A semeadura dos porta-enxertos foi realizada em agosto de 2012 e os ramos foram coletados em julho de 2013. Uma parte dos ramos foi utilizada para a realização da enxertia (métodos de borbulhia e garfagem) em porta-enxertos de um ano de idade e a outra parte foi armazenada sob baixa temperatura (estacas envoltas em papel umedecido, embrulhadas em sacos de polietileno colocadas em câmara fria a 4°C), pelos meses de agosto a dezembro. A cada 30 dias, uma quantidade de ramos foi removida da câmara fria para a realização das enxertias por borbulhia e garfagem e para a quantificação dos açúcares totais e amido dos ramos porta-borbulhas/garfos armazenados. Passados 120 dias da realização das enxertias, foram mensurados o comprimento e diâmetro do broto, número de folhas, porcentagem de brotação, massa seca da parte aérea e das raízes dos enxertos. Conclui-se que não há diferença na brotação dos enxertos para as diferentes épocas, porém, em mudas enxertadas pelo método de garfagem, há maior crescimento quando os garfos são armazenados a frio durante 60 a 120 dias.

Relationship between production, nematodes and "redness" in strawberries / Relação entre produção, nematoide e o sintoma de "vermelhão" em morangueiros

ABSTRACT: In recent years "redness" has increasingly appeared in strawberry plants with leaves taking on a reddish color. No causal agent has been associated with plants. Since strawberries presented problems due to the incidence of nematodes, the purpose of this study was to look at the relationship between production, resistance to the Meloidogyne hapla nematode and the "redness" symptom in strawberry cultivars. Two experiments were performed, both with the 'Camino Real', 'Festival', 'Oso Grande', 'Albion' and 'Camarosa' cultivars. The first experiment was performed in the field, where the following were evaluated: strawberry production, fruit quality, macro and micronutrient contents in fruit and leaves, percentage of plant survival, incidence of nematodes, quantity of eggs in the roots and juveniles in the soil, and the incidence of Botrytis cinerea . In the second experiment, the strawberries were transplanted into pots and filled with pinus bark-based commercial substrate. Half the pots were inocculated with Meloidogyne hapla . Cultivars presented differences in fruit production and also in the incidence of "redness". Lowest performance in production was related to the high incidence of the nematode Meloidogyne hapla. 'Oso Grande' and 'Albion' presented nematode-resistant behavior. It was possible find a relationship between the incidence of the Meloidogyne hapla nematode, and the incidence of "redness" only 'Camino Real' cultivar.

RESUMO: Nos últimos anos, vem aumentando o aparecimento do "vermelhão" nos morangueiros, que ficam com as folhas avermelhadas. Nenhum agente causal foi associado às plantas. Devido aos plantios de morangueiros apresentarem problemas pela incidência de nematoide, o objetivo do presente trabalho foi verificar a relação entre produção, resistência ao nematoide Meloidogyne hapla e o sintoma de "vermelhão" em cultivares de morangueiro. Foram realizados dois experimentos, ambos com as cultivares 'Camino Real', 'Festival', 'Oso Grande', 'Albion' e 'Camarosa'. O primeiro experimento foi realizado a campo, onde se avaliaram a produção de morangos, qualidade dos frutos, teores de macro e micronutrientes em frutos e folhas, porcentagem de sobrevivência das plantas, incidência de nematoides, quantidade de ovos nas raízes e juvenis no solo e a incidência de Botrytis cinerea. No segundo experimento, os morangueiros foram transplantados em vasos e preenchidos com substrato comercial a base de casca de pinus. Metade dos vasos foi inoculada com Meloidogyne hapla. As cultivares apresentaram diferenças na produção de frutos e também na incidência de "vermelhão". O menor desempenho produtivo relaciona-se com a alta incidência de nematoide Meloidogyne hapla. 'Oso Grande' e 'Albion' se comportaram como resistentes ao nematoide. Foi possível relacionar a incidência de nematoide Meloidogyne hapla com a de "vermelhão" apenas na cultivar 'Camino Real'.

Influence of Subtropical Region Strawberry Cultivars on Jelly Characteristics.

At the end of the production period of strawberries grown in subtropical regions, postharvest durability is severely diminished due to rising temperatures which compromises the commercialization of fresh fruit. An ideal option would be to process strawberries in the form of preserves, jams, and jellies. Along this line it becomes extremely important to conduct a survey of which cultivars grown in subtropical regions are more suitable for processing in the form of jelly, as well as to understand what the consumer profile is for this product. The objective of this study was to evaluate the influence of different strawberry cultivars grown in subtropical regions of Brazil (Camarosa, Festival, San Andreas, Oso Grande, Camino Real, and Albion) on the physicochemical characteristics, rheological properties and sensory acceptance of the resulting jelly in order to identify cultivars with the greatest potential for industrial use. The strawberry cultivars presented different physicochemical characteristics which resulted in jellies with different physicochemical and rheological characteristics. In this study, however, we verified that all cultivars have potential to be processed in the form of jelly due to good acceptance of all formulations prepared. In general consumers prefer a lighter-colored strawberry jelly, with a less intense red color, more acidic, and less consistent/firm.