Influence of Sucrose and Activated Charcoal on Phytochemistry and Vegetative Growth in Zephyranthes irwiniana (Ravenna) Nic. García (Amaryllidaceae).

Zephyranthes irwiniana (Ravenna) Nic. García is an endemic, red list threatened species from the Brazilian savanna (Cerrado) with pharmacological potential to treat the symptoms of Alzheimer's Disease (AD). This work analyzed the vegetative growth and phytochemistry of its potential compounds, in response to variations in sucrose concentration and activated carbon (AC). Seeds were germinated in vitro and in the greenhouse. The in vitro bulbs were separated in six treatments with different sucrose concentrations (30, 45 and 60 gL-1) and/or AC (1 gL-1). Biomass increases in individuals grown in the greenhouse were higher than those cultivated in vitro. Sucrose concentration significantly increased biomass and root number. AC had a positive influence on leaf and root size, and a negative influence on root number. GC-MS analyses indicated great variation in the abundance of α-terpenyl-acetate, ethyl linoleate, clionasterol and lycorine between treatments, with maximum concentrations of 53.06%, 38.68, 14.34% and 2.57%, respectively. Histolocalization tests indicated the presence of alkaloids in the leaf chlorenchyma and bulb cataphylls. Finally, the present study provided new evidence that the constitution of the culture medium directly influences the vegetative growth and phytochemistry of this species, providing a good medium condition for propagating the species under threat.

Responses of tomato hybrid cultivars to soil application of humic acid under greenhouse conditions

Abstract Responses of three tomato (Lycopersicon esculentum Mill.) hybrids viz. 'Luanova', 'Savarona' and 'Tessera' to various doses (0, 0.5, 1.0, 1.5 and 2.0 g L-1) of soil application of humic acid (HA) were evaluated in terms of plant growth, productivity and quality of fruits, under greenhouse conditions, during 2011-12 and 2012-13. In addition to improved quality characteristics, higher values for yield and yield components were recorded for tomato fruits harvested from plants of 'Tessera' cultivar compared to those harvested from other hybrids tested, regardless of growing seasons. Plants from 'Luanova' cultivar were, however, earlier in fruiting with higher number of fruits per plant. Soil application of HA presented positive effects on yield and physicochemical quality of tomato fruits irrespective of the dose of HA and the cultivar investigated, in both seasons. Soil application of HA at higher dose 1.5 g L-1 exhibited better results in all the three tomato cultivars tested, in terms of their vegetative and reproductive growth, and significantly improved the physicochemical quality of their fruits. Conclusively, the tomato hybrid 'Tessera' was found suitable for cultivation under greenhouse conditions while soil application of aqueous solution of HA @ 1.5 g L-1 substantially resulted in higher production of quality tomato fruits.

Resumo Respostas de três híbridos de tomate (Lycopersicon esculentum Mill.) viz. 'Luanova', 'Savarona' e 'Tessera' para várias doses (0, 0,5, 1,0, 1,5 e 2,0 g L-1) de aplicação de ácido húmico (AH) no solo foram avaliadas em termos de crescimento da planta, produtividade e qualidade de frutas, em casa de vegetação, durante 2011-12 e 2012-13. Além das características de qualidade melhoradas, valores mais elevados para o rendimento e os componentes do rendimento foram registrados para frutos de tomate colhidos de plantas do cultivar 'Tessera' em comparação com aqueles colhidos de outros híbridos testados, independentemente das estações de cultivo. As plantas do cultivar 'Luanova', no entanto, frutificaram mais cedo com maior número de frutos por planta. A aplicação de AH no solo apresentou efeitos positivos sobre a produtividade e a qualidade físico-química dos frutos de tomate, independentemente da dose de AH e do cultivar investigado, nas duas safras. A aplicação de HA no solo na dose maior de 1,5 g L-1 apresentou melhores resultados nos três cultivares de tomate testados, quanto ao crescimento vegetativo e reprodutivo, e melhorou significativamente a qualidade físico-química dos frutos. Conclusivamente, o híbrido de tomate 'Tessera' foi considerado adequado para cultivo em casa de vegetação, enquanto a aplicação no solo de solução aquosa de HA @ 1,5 g L-1 resultou substancialmente em maior produção de frutos de tomate de qualidade.

A soil water indicator for a dynamic model of crop and soil water interaction.

Water scarcity is a critical issue in agriculture, and the development of reliable methods for determining soil water content is crucial for effective water management. This study proposes a novel, theoretical, non-physiological indicator of soil water content obtained by applying the next-generation matrix method, which reflects the water-soil-crop dynamics and identifies the minimum viable value of soil water content for crop growth. The development of this indicator is based on a two-dimensional, nonlinear dynamic that considers two different irrigation scenarios: the first scenario involves constant irrigation, and the second scenario irrigates in regular periods by assuming each irrigation as an impulse in the system. The analysis considers the study of the local stability of the system by incorporating parameters involved in the water-soil-crop dynamics. We established a criterion for identifying the minimum viable value of soil water content for crop growth over time. Finally, the model was calibrated and validated using data from an independent field study on apple orchards and a tomato crop obtained from a previous field study. Our results suggest the advantages of using this theoretical approach in modeling the plants' conditions under water scarcity as the first step before an empirical model. The proposed indicator has some limitations, suggesting the need for future studies that consider other factors that affect soil water content.

Endophytic colonization of five Trichoderma species and their effects on growth of a Eucalyptus hybrid.

The study aimed to evaluate the effectiveness of endophytic colonization via leaf and root inoculation of five Trichoderma species in a Eucalyptus hybrid, as well as the effects of inoculation on plant growth. The experimental design was completely randomized in a 6 × 2 factorial scheme. Plant growth was evaluated during the experimental period at three different times: 20 days after inoculation (d.a.i), 40 d.a.i., and 60 d.a.i. A statistical difference was observed between the inoculation methods during each period and between the Trichoderma species. Plants inoculated with T. asperellum showed the greatest growth among the treatments. Root-inoculated plants produced the greatest growth response. This showed that the presence of Trichoderma in the roots assisted in nutrient assimilation, promoted greater plant growth, when compared with leaf-inoculated plants. Evaluation of the effectiveness of endophytic colonization was performed at each sampling period by collecting leaf samples, and at 60 d.a.i., by collecting leaf, stem, and root samples. T. longibrachiatum and T. harzianum were isolated from leaves at 20 d.a.i., with an increase in the number of colonized plants throughout the evaluation of leaf-inoculated plants. In root-inoculated plants, treatment with T. longibrachiatum, T. harzianum, and T. asperellum presented the highest endophytic colonization in the stem and root samples (at 60 d.a.i.).

CRISPR/Cas9-mediated knockout of a polyester synthase-like gene delays flowering time in alfalfa.

KEY MESSAGE: T-DNA and CRISPR/Cas9-mediated knockout of polyester synthase-like genes delays flowering time in Arabidopsis thaliana and Medicago sativa (alfalfa). Thus, we here present the first report of edited alfalfa with delayed flowering.

Sequential cutting of Urochloa brizantha cv MG 5 changes flowering season and seed production components / Corte sequencial de Urochloa brizantha cv MG 5 altera época de florescimento e componentes de produção de sementes

In tropical grass seed production fields, reducing plant size can increase the solar radiation to the base of the plant canopy and improve the quantity and quality of the seeds produced. This research studied the responses of the production components, the productivity, and the seed quality of U. brizantha cv. MG-5 to different canopy sequential cuttings under cultivation conditions in rain fed systems. Two experiments were carried out (agricultural year 2015/16 (s1) and 2016/17 (s2)) in a randomized block experimental design with four repetitions. The treatments consisted of sequential cut-off, indicating the month of the last cut and the agricultural year: for the 2015/16 agricultural year: Aug - s1, Sep - s1, Oct - s1, Nov - s1, Dec - s1, Jan - s1, and Feb - s1; for the 2016/17 agricultural year: Aug - s2; Set - s2; Nov - s2; Dec - s2; Jan - s2, and Feb - s2. Plant growth biometrics, seed quality variables, and productivity were evaluated. The sequential cut strategy increased the productivity and quality of pure seeds when the final cuts were done between November and December. Cuts performed after December increased the reproductive components. However, in the region in question, rainfall levels compromised seed filling; and therefore productivity and quality since the flowering of these cuttings (January and February) occurs in May.

Em campos de produção de sementes de forrageiras tropicais, a redução do porte das plantas pode ser uma estratégia de melhorar os índices de radiação solar no dossel inferior da lavoura, com possíveis consequências positivas para a produtividade e qualidade das sementes produzidas. Neste contexto, foi desenvolvido um trabalho com propósito de estudar as respostas dos componentes de produção, produtividade e qualidade de sementes de U. brizantha cv. MG-5 em razão de cortes sequenciais da parte aérea, em condições de cultivo em sistema de sequeiro. Para tanto foram implantados dois experimentos (ano agrícola 2015/16 - s1 e ano agrícola 2016/17 - s2), em que se adotou o delineamento experimental em blocos casualizados, com quatro repetições. Os tratamentos foram constituídos por cortes sequenciais da parte aérea, sendo que os cortes mensais e a nomenclatura dos respectivos tratamentos indicam o mês do último corte e ano agrícola: Ago - s1; Set - s1; Out - s1; Nov - s1; Dez - s1; Jan - s1 e Fev - s1 para o ano agrícola 2015/16 (s1) e Ago - s2; Set - s2; Nov - s2; Dez - s2; Jan - s2 e, Fev - s2 para o ano agrícola 2016/17 (s2). Foram avaliadas variáveis biométricas de crescimento da planta, e variáveis de qualidade e produtividade de sementes. O manejo de cortes sequenciais incrementa a produtividade e qualidade de sementes puras para cortes finais realizados entre novembro e dezembro. Cortes realizados posteriormente a dezembro aumentam os componentes reprodutivos, entretanto, na região em questão, os índices pluviométricos comprometem o enchimento das sementes e consequentemente a produtividade e qualidade, visto que o florescimento destas épocas de cortes (janeiro e fevereiro) ocorrem em maio.

Initial performance of 'Gem' avocado trees in the Central-Western region of São Paulo State / Desempenho inicial de abacateiros 'Gem' na Região Centro-Oeste do Estado de São Paulo

The introduction of new avocado cultivars into producing countries of the Southern Hemisphere may extend the offer period of fresh fruit for export. The 'Gem' ('3-29-5') avocado is known for extending the marketing period of 'Hass'-like avocados. This study aimed to evaluate the horticultural performance of 'Gem' avocado trees between the 4th and 6th years after planting (2016-2018), in a commercial orchard in the Central-Western region of the State of São Paulo, Brazil. 'Gem' avocado trees grafted onto seedling rootstocks were evaluated regarding tree size, shoot growth, flowering, and fruit yield, quality and maturation. In the evaluated biennium, the trees showed a strong upright growth habit and compact tree size. Flowering occurred mainly in indeterminate inflorescences. Fruit yield varied between 106.89 to116.89 kg tree-¹, and 75-91% of the fruit classified with in size counts 12 (306 to 365 g/fruit) to 18 (211 to 235 g/fruit), and reached physiological maturity in late June, but could be picked until October, i.e, four to eight months later than 'Hass'. 'Gem' is a new alternative for extending fruit offer of late-maturity avocado cultivars and allowing higher profit to the farmers.

A introdução de novas cultivares de abacate em países produtores do Hemisfério Sul pode estender o período de oferta do fruto fresco para exportação. O abacate 'Gem' ('3-29-5') é conhecido por estender o período de comercialização de abacates do tipo 'Hass'. Este estudo teve como objetivo avaliar o desempenho horticultural de abacateiros 'Gem' entre o 4º e 6º anos após o plantio (2016-2018) em pomar comercial na região Centro-Oeste do Estado de São Paulo, Brasil. Os abacateiros 'Gem' enxertados em porta-enxertos obtidos de sementes foram avaliados em relação ao tamanho da árvore, crescimento do broto, florescimento e produção, qualidade e maturação de frutos. No biênio avaliado, as árvores apresentaram forte hábito de crescimento ereto e tamanho compacto. O florescimento ocorreu principalmente com inflorescências indeterminadas. A produção variou entre 106,89 a 116,89 kg/planta e 75-91% dos frutos classificados nas categorias de calibre 12 (306 a 365 g/fruto) a 18 (211 a 235 g/fruto), e atingiram a maturidade fisiológica no final de junho, podendo ser colhido até outubro, ou seja, quatro a oito meses depois de 'Hass'. 'Gem' é uma nova alternativa para estender a oferta de cultivares de abacate de maturação tardia e permitir maior lucro aos agricultores.

Initial performance of 'Gem' avocado trees in the Central-Western region of São Paulo State / Desempenho inicial de abacateiros 'Gem' na Região Centro-Oeste do Estado de São Paulo

The introduction of new avocado cultivars into producing countries of the Southern Hemisphere may extend the offer period of fresh fruit for export. The 'Gem' ('3-29-5') avocado is known for extending the marketing period of 'Hass'-like avocados. This study aimed to evaluate the horticultural performance of 'Gem' avocado trees between the 4th and 6th years after planting (2016-2018), in a commercial orchard in the Central-Western region of the State of São Paulo, Brazil. 'Gem' avocado trees grafted onto seedling rootstocks were evaluated regarding tree size, shoot growth, flowering, and fruit yield, quality and maturation. In the evaluated biennium, the trees showed a strong upright growth habit and compact tree size. Flowering occurred mainly in indeterminate inflorescences. Fruit yield varied between 106.89 to116.89 kg tree-¹, and 75-91% of the fruit classified with in size counts 12 (306 to 365 g/fruit) to 18 (211 to 235 g/fruit), and reached physiological maturity in late June, but could be picked until October, i.e, four to eight months later than 'Hass'. 'Gem' is a new alternative for extending fruit offer of late-maturity avocado cultivars and allowing higher profit to the farmers.(AU)

A introdução de novas cultivares de abacate em países produtores do Hemisfério Sul pode estender o período de oferta do fruto fresco para exportação. O abacate 'Gem' ('3-29-5') é conhecido por estender o período de comercialização de abacates do tipo 'Hass'. Este estudo teve como objetivo avaliar o desempenho horticultural de abacateiros 'Gem' entre o 4º e 6º anos após o plantio (2016-2018) em pomar comercial na região Centro-Oeste do Estado de São Paulo, Brasil. Os abacateiros 'Gem' enxertados em porta-enxertos obtidos de sementes foram avaliados em relação ao tamanho da árvore, crescimento do broto, florescimento e produção, qualidade e maturação de frutos. No biênio avaliado, as árvores apresentaram forte hábito de crescimento ereto e tamanho compacto. O florescimento ocorreu principalmente com inflorescências indeterminadas. A produção variou entre 106,89 a 116,89 kg/planta e 75-91% dos frutos classificados nas categorias de calibre 12 (306 a 365 g/fruto) a 18 (211 a 235 g/fruto), e atingiram a maturidade fisiológica no final de junho, podendo ser colhido até outubro, ou seja, quatro a oito meses depois de 'Hass'. 'Gem' é uma nova alternativa para estender a oferta de cultivares de abacate de maturação tardia e permitir maior lucro aos agricultores.(AU)

Ingestive behavior and infrared thermography of Holstein × Zebu crossbreed cows in the final third of gestation in different pastoral environments

This study aimed to evaluate the ingestive behavior and body surface temperature of F1 Holstein × Zebu cows that were non-lactating in the final third of gestation and managed in two pastoral environments. Forty F1 Holstein × Zebu cows divided into two pastoral environments were evaluated: signal grass (Urochloa decumbens cv. Basilisk) deferred at the beginning of regrowth and pasture of xaraés grass (Urochloa brizantha cv. Xaraés) in vegetative growth in four periods during the day (morning, afternoon, night and dawn), following the completely randomized design in a factorial scheme. Each cow is the experimental unit. The total grazing time was 32.22% higher in the signal grass than xaraés grass (averageof 479.50 minutes). There was an interaction between the pastoral environments and the times of day on the black globe temperature and humidity index (BGHI). In the pasture of signal grass, the BGHI was 19.07% higher in the morning and afternoon periods than the average (68.95) verified during the night and dawn. F1 Holstein × Zebu cows grazing time in the final third of gestation is influenced by the pasture condition and not by the climate since they feed in a high BGHI environment.(AU)

Ingestive behavior and infrared thermography of Holstein × Zebu crossbreed cows in the final third of gestation in different pastoral environments

This study aimed to evaluate the ingestive behavior and body surface temperature of F1 Holstein × Zebu cows that were non-lactating in the final third of gestation and managed in two pastoral environments. Forty F1 Holstein × Zebu cows divided into two pastoral environments were evaluated: signal grass (Urochloa decumbens cv. Basilisk) deferred at the beginning of regrowth and pasture of xaraés grass (Urochloa brizantha cv. Xaraés) in vegetative growth in four periods during the day (morning, afternoon, night and dawn), following the completely randomized design in a factorial scheme. Each cow is the experimental unit. The total grazing time was 32.22% higher in the signal grass than xaraés grass (averageof 479.50 minutes). There was an interaction between the pastoral environments and the times of day on the black globe temperature and humidity index (BGHI). In the pasture of signal grass, the BGHI was 19.07% higher in the morning and afternoon periods than the average (68.95) verified during the night and dawn. F1 Holstein × Zebu cows grazing time in the final third of gestation is influenced by the pasture condition and not by the climate since they feed in a high BGHI environment.

Ingestive behavior and infrared thermography of Holstein × Zebu crossbreed cows in the final third of gestation in different pastoral environments

This study aimed to evaluate the ingestive behavior and body surface temperature of F1 Holstein × Zebu cows that were non-lactating in the final third of gestation and managed in two pastoral environments. Forty F1 Holstein × Zebu cows divided into two pastoral environments were evaluated: signal grass (Urochloa decumbens cv. Basilisk) deferred at the beginning of regrowth and pasture of xaraés grass (Urochloa brizantha cv. Xaraés) in vegetative growth in four periods during the day (morning, afternoon, night and dawn), following the completely randomized design in a factorial scheme. Each cow is the experimental unit. The total grazing time was 32.22% higher in the signal grass than xaraés grass (averageof 479.50 minutes). There was an interaction between the pastoral environments and the times of day on the black globe temperature and humidity index (BGHI). In the pasture of signal grass, the BGHI was 19.07% higher in the morning and afternoon periods than the average (68.95) verified during the night and dawn. F1 Holstein × Zebu cows grazing time in the final third of gestation is influenced by the pasture condition and not by the climate since they feed in a high BGHI environment.(AU)

Initial performance of 'Gem' avocado trees in the Central-Western region of São Paulo State / Desempenho inicial de abacateiros 'Gem' na Região Centro-Oeste do Estado de São Paulo

The introduction of new avocado cultivars into producing countries of the Southern Hemisphere may extend the offer period of fresh fruit for export. The 'Gem' ('3-29-5') avocado is known for extending the marketing period of 'Hass'-like avocados. This study aimed to evaluate the horticultural performance of 'Gem' avocado trees between the 4th and 6th years after planting (2016-2018), in a commercial orchard in the Central-Western region of the State of São Paulo, Brazil. 'Gem' avocado trees grafted onto seedling rootstocks were evaluated regarding tree size, shoot growth, flowering, and fruit yield, quality and maturation. In the evaluated biennium, the trees showed a strong upright growth habit and compact tree size. Flowering occurred mainly in indeterminate inflorescences. Fruit yield varied between 106.89 to 116.89 kg tree-1, and 75-91% of the fruit classified within size counts 12 (306 to 365 g/fruit) to 18 (211 to 235 g/fruit), and reached physiological maturity in late June, but could be picked until October, i.e, four to eight months later than 'Hass'. 'Gem' is a new alternative for extending fruit offer of late-maturity avocado cultivars and allowing higher profit to the farmers.(AU)

A introdução de novas cultivares de abacate em países produtores do Hemisfério Sul pode estender o período de oferta do fruto fresco para exportação. O abacate 'Gem' ('3-29-5') é conhecido por estender o período de comercialização de abacates do tipo 'Hass'. Este estudo teve como objetivo avaliar o desempenho horticultural de abacateiros 'Gem' entre o 4º e 6º anos após o plantio (2016-2018) em pomar comercial na região Centro-Oeste do Estado de São Paulo, Brasil. Os abacateiros 'Gem' enxertados em porta-enxertos obtidos de sementes foram avaliados em relação ao tamanho da árvore, crescimento do broto, florescimento e produção, qualidade e maturação de frutos. No biênio avaliado, as árvores apresentaram forte hábito de crescimento ereto e tamanho compacto. O florescimento ocorreu principalmente com inflorescências indeterminadas. A produção variou entre 106,89 a 116,89 kg/planta e 75-91% dos frutos classificados nas categorias de calibre 12 (306 a 365 g/fruto) a 18 (211 a 235 g/fruto), e atingiram a maturidade fisiológica no final de junho, podendo ser colhido até outubro, ou seja, quatro a oito meses depois de 'Hass'. 'Gem' é uma nova alternativa para estender a oferta de cultivares de abacate de maturação tardia e permitir maior lucro aos agricultores.(AU)

Modeling vegetative vigour in grapevine: unraveling underlying mechanisms.

Mechanistic modeling constitutes a powerful tool to unravel complex biological phenomena. This study describes the construction of a mechanistic, dynamic model for grapevine plant growth and canopy biomass (vigor). To parametrize and validate the model, the progeny from a cross of Ramsey (Vitis champinii) × Riparia Gloire (V. riparia) was evaluated. Plants with different vigor were grown in a greenhouse during the summer of 2014 and 2015. One set of plants was grafted with Cabernet Sauvignon. Shoot growth rate (b), leaf area (LA), dry biomass, whole plant and root specific hydraulic conductance (kH and Lpr), stomatal conductance (gs), and water potential (Ψ) were measured. Partitioning indices and specific leaf area (SLA) were calculated. The model includes an empirical fit of a purported seasonal pattern of bioactive GAs based on published seasonal evolutionary levels and reference values. The model provided a good fit of the experimental data, with R = 0.85. Simulation of single trait variations defined the individual effect of each variable on vigor determination. The model predicts, with acceptable accuracy, the vigor of a young plant through the measurement of Lpr and SLA. The model also permits further understanding of the functional traits that govern vigor, and, ultimately, could be considered useful for growers, breeders and those studying climate change.

Evaluation of connected clonal growth of Solidago chilensis as an avoidance mechanism in copper-polluted soils.

Plant resistance to metals can be achieved by two strategies, tolerance and avoidance. Although metal tolerance has been broadly studied in terrestrial plants, avoidance has been less considered as a strategy to cope with soil metal pollution. Avoidance may be an effective alternative in herbaceous plants with connected clonal growth in environments having high heterogeneity in soil micro-spatial distribution of available metals and other soil conditions (i.e. organic matter). In this study, we performed a laboratory experiment on clonal growth of Solidago chilensis when exposed to copper-spiked soils (800 mg kg-1) at different depths (0, 2, 5 and 8 cm depth), with (20%) and without addition of organic matter to mimic contrasting microhabitats found at smelter hinterlands (i.e. open bare ground and microhabitats below shrubs). Results showed that plants grown in the 2 cm-depth Cu-spiked soils were able to growth and produce ramets and rhizomes. However, increased Cu uptake of plants determined phytotoxic effects and a reduction in clonal spread in the 5 cm- and 8 cm-depth Cu-spiked soils. Addition of organic matter to the Cu-spiked soil layers allowed clonal spread. Considering that ramet and rhizome production is decreased but not inhibited when copper pollution is restricted to the uppermost soil layer (2 cm depth) and that organic matter eliminated soil copper toxicity allowing normal clonal spread, connected clonal growth may be an effective avoidance mechanism of Solidago chilensis, particularly in environments with high heterogeneity in micro-spatial distribution of metals and organic matter in the soil profile and between microhabitats.

Long-term effect of carbohydrate reserves on growth and reproduction of Prosopis denudans (Fabaceae): implications for conservation of woody perennials.

Prosopis denudans, an extreme xerophyte shrub, is consumed by ungulates and threatened by firewood gathering, because it is one of the preferred species used by Mapuche indigenous people of Patagonia. In a scenario of uncontrolled use of vegetation, it is very difficult to develop a conservation plan that jointly protects natural resources and its users. We performed a field experiment to assess the impact of defoliation on growth, reproduction and stores of a wild population of P. denudans. We imposed four levels of defoliation (removal of 100, 66, 33 and 0% of leaves) and evaluated the short- and long-term (3 years) effects of this disturbance. Seasonal changes in shoot carbohydrates suggested that they support leaf-flush and blooming. Severely defoliated individuals also used root reserves to support growth and leaf-flush after clipping. Vegetative growth was not affected by defoliation history. Leaf mass area increased after the initial clipping, suggesting the development of structural defenses. The depletion of root reserves at the end of the first year affected inflorescence production the following spring. We conclude that P. denudans shrubs could lose up to one-third of their green tissues without affecting growth or inflorescence production. The removal of a higher proportion of leaves will diminish stores, which in turn, will reduce or completely prevent blooming and, therefore, fruit production the following seasons. Very few studies integrate conservation and plant physiology, and we are not aware, so far, of any work dealing with long-term plant carbon economy of a long-lived perennial shrub as an applied tool in conservation. These results might help the development of management strategies that consider both the use and the conservation of wild populations of P. denudans.

Efeito da Aloe arborescens Miller e da Aloe barbadensis Miller sobre o desenvolvimento vegetativo em Aspergillus nidulans / Effects of the Aloe arborescens Millerand Aloe barbadensis Milleron over vegetative growth in the Aspergillus nidulans

RESUMOA pesquisa de produtos naturais benéficos à saúde humana vem crescendo nos últimos 20 anos. Considerando que as plantas de Aloe são amplamente utilizadas pela população humana, em geral de maneira terapêutica, o objetivo deste estudo foi avaliar os efeitos de Aloearborescens Miller e Aloe barbadensis Miller, sobre o desenvolvimento vegetativo de linhagens normais e mutantes de Aspergillus nidulans. Conídios da linhagem biA1methG1, MSE e CLB3 de A. nidulans, foram inoculados em meio completo sem (Controle) e com extratos das duas espécies incubados por 2, 4, 6 e 8 horas a 37ºC, no escuro. Foi analisado em microscópio óptico, 200 conídios de cada tratamento. Para o desenvolvimento das colônias, as linhagens foram inoculadas no centro das placas juntamente com o meio de cultura sólido e sobre a membrana de diálise, visando a medição do diâmetro e do peso. A análise estatística foi baseada no teste de Tukey e todos os procedimentos experimentais foram conduzidos em triplicata. Todas as linhagens apresentaram interferências positivas quando expostas às plantas de Aloe, porém, de maneira variada. Ambas as espécies aceleraram a germinação em todas as linhagens testadas e atuaram na redução significativa de conídios mortos e/ou malformados. Em relação ao desenvolvimento vegetativo, todos os dados referentes ao peso úmido e diâmetro corrigido dos tratamentos demonstraram progressos, contudo, a razão diâmetro/peso apresentou somente na linhagem MSE, ação favorável dos tratamentos naturais. As informações deste estudo sugerem benefícios de A. arborescens e A. barbadensis, justificando a importância e continuidade da investigação, para melhor elucidar os mecanismos de ação dessas plantas.

ABSTRACTThe researches about natural products that arebeneficial to human health have been growing over the past 20 years. Since Aloe plants are broadly used by the general population, frequently due to therapeutic reasons, the objective of this study was to evaluate the effects of Aloe arborescens Millerand Aloe barbadensis Miller on the vegetative growth of normal and mutant strains of Aspergillus nidulans. The conidia of thebiA1methG1, MSE and CLB3 strains of A. nidulans were inoculated in complete environment without (control) and with extracts of two species of Aloeincubated for 2, 4, 6 and 8 hours at 37˚C. 200 conidia were analyzed by optical microscopy. For the development of the colonies, the strains were inoculated in the center of the plates together with the solid environment of the cultivation and over the dialysis membrane for measuring the diameter and weighing. The statistical analysis was based on the Tukey test and all experimental procedures were performed in triplicate. All strains showed positive interference when exposed to Aloe plants, however, through different manners. Both species have accelerated the germination in all tested strains and acted in the significant reduction of dead and / or malformed conidia. Regarding the vegetative growth, all data related to wet weight and corrected diameter of the treatments revealed progress, however, the ratio diameter/weightpresented improvement only in the MSE lineage, favorable action of natural treatments. The information from this study suggest that A. arborescens and A. barbadensis are beneficial, thus justifying the importance of research maintenance in order to better elucidate the action mechanisms of these plants.

Performance of ‘Okitsu satsuma mandarin trees on different rootstocks in Northwestern Paraná State / Comportamento de tangerineira satsuma ‘Okitsu sobre diferentes porta-enxertos no Noroeste do Paraná

O limoeiro ‘Cravo é o principal porta-enxerto utilizado para citros no estado do Paraná e temapresentado bom desempenho para as diferentes cultivares de copa. Porém, são necessários estudos paradiversificar os porta-enxertos utilizados no Estado e também para serem utilizados em cultivares aindapouco exploradas comercialmente. O objetivo deste estudo foi avaliar o desenvolvimento vegetativo, aprodução e a qualidade de frutos da tangerineira satsuma ‘Okitsu (Citrus unshiu Marc.) enxertada sobrediferentes porta-enxertos. O pomar foi implantado na Estação Experimental de Paranavaí do InstitutoAgronômico do Paraná IAPAR, em Paranavaí, PR, em janeiro de 2001. O delineamento experimentalfoi de blocos ao acaso, com nove tratamentos, três repetições e duas plantas úteis por parcela. Osporta=enxertos utilizados foram limoeiro ‘Cravo (Citrus limonia Osb.), tangerineira ‘Cleópatra(Citrus reshni hort. ex Tanaka), citrangeiro ‘C-13 [Citrus sinensis x Poncirus trifoliata (L.) Raf.],limoeiro ‘Volkameriano (Citrus volkameriana V. Ten. e Pasq.), citrangeiro ‘Carrizo [C. sinensis x P.trifoliata (L.) Raf.], tangerineira ‘Sunki (Citrus sunki hort. ex Tanaka), trifoliata [P. trifoliata (L.) Raf.],citrumeleiro ‘Swingle [Citrus paradisi Macfad. cv. Duncan x P. trifoliata (L.) Raf.] e laranjeira ‘CaipiraDAC [C. sinensis (L.) Osb.]. O maior volume de copa das plantas de satsuma ‘Okitsu foi induzidopela tangerineira ‘Cleópatra com 37,1 m3, e o menor foi para as plantas enxertadas em ‘Trifoliata,com 9,9 m3. O citrumeleiro ‘Swingle proporcionou maior relação entre diâmetro do tronco abaixoe acima do ponto de enxertia. As maiores produções acumuladas em oito safras foram induzidas porlimoeiros ‘Volkameriano e ‘Cravo, laranjeira ‘Caipira DAC, tangerineira ‘Cleópatra e citrangeiro‘Carrizo, com valores entre 867,3 kg e 989,6 kg...(AU)

In the state of Paraná, ‘Rangpur lime is the main citrus rootstock, which has provided good performancefor trees of different cultivars planted in the State. However, rootstock diversification is needed as wellas to identify the best ones for citrus cultivars less explored commercially yet. The objective of thisstudy was to evaluate the vegetative growth, yield and fruit quality of ‘Okitsu satsuma mandarin trees(Citrus unshiu Marc.) grafted on nine rootstocks in the Northwest region of the state of Paraná, Brazil.The orchard was established in the Paranavaí Experimental Station of the Agronomic Institute of Paraná,Paranavaí, PR, on January 2001. The experimental design was randomized blocks with nine treatments,three replications, and two trees per plot. The rootstocks included in this study were ‘Rangpur lime(Citrus limonia Osb.), ‘Cleópatra mandarin (Citrus reshni hort. ex Tanaka), ‘C-13 citrange [Citrussinensis × Poncirus trifoliata orange (L.) Raf.], ‘Volkamer lemon (Citrus volkameriana V. Ten. ePasq.), ‘Carrizo citrange [C. sinensis × P. trifoliata (L.) Raf.], ‘Sunki mandarin (Citrus sunki hort.ex Tanaka), ‘Trifoliate orange [P. trifoliata (L.) Raf. ], ‘Swingle citrumelo [Citrus paradisi Macfad.cv. Duncan × P. trifoliata (L.) Raf.], and ‘Caipira DAC sweet orange [C. sinensis (L.) Osb.]. Thelargest tree canopy was induced by ‘Cleópatra mandarin and the lowest by ‘Trifoliate orange, with37.1 m3 and 9.9 m3 of tree canopy, respectively. The highest relationship between scion and rootstocktrunk diameter was observed for trees grafted on ‘Swingle citrumelo. The largest cumulative yieldsover eight seasons were induced by ‘Volkamer lemon, ‘Rangpur lime, ‘Caipira DAC sweet orange,‘Cleópatra mandarin, and ‘Carrizo citrange, ranging from 867.3 to 989.6 kg per tree. These rootstocksalso induced the largest fruit mass, along with ‘Sunki, ranging from 173.3 to 188.0 g. ‘Trifoliateorange...(AU)

Substratos e recipientes para a produção de porta-enxertos de citros irrigados por subcapilaridade / Substrates and containers for the citrus rootstocks' production irrigated by capillarity

O conhecimento do porta-enxerto, do substrato e do recipiente são fundamentais para a definição do período necessário para produzir mudas cítricas de qualidade. O objetivo deste trabalho foi avaliar a emergência de plântulas e o desenvolvimento vegetativo de seis porta-enxertos cítricos, cultivados em dois substratos e mantidos em diferentes recipientes, em sementeira, irrigados por subcapilaridade. Foram testados dois substratos comerciais e a semeadura foi realizada em tubetes com 50cm³, tubetes com 120cm³ e bandejas de isopor contendo 72 células com volume de 120cm³. Os seis porta-enxertos cítricos avaliados foram: Trifoliata [Poncirus trifoliata [L.] Raf.]; Flying Dragon [Poncirus trifoliata (L.) Raf. var. monstrosa]; limoeiro Volkameriano (Citrus volkameriana Pasq.), citrangeiro Fepagro C37 [P. trifoliata x Citrus sinensis [L.] Osbeck.], tangerineira Sunki (C. sunki hort. ex Tan.) e citrumeleiro Swingle (P. trifoliata x C. paradisi). Avaliou-se emergência, altura e diâmetro das plantas ao longo do cultivo em casa de vegetação. Em laboratório, avaliou-se massa fresca e seca da parte aérea e raiz, número de folhas, área foliar por folha e área foliar por planta. Nas avaliações de emergência de plântulas, a tangerineira Sunki, o limoeiro Volkameriano e o citrumeleiro Swingle apresentaram maiores taxas em relação ao Trifoliata, ao citrangeiro Fepagro C 37 e ao Flying Dragon. Ao empregar-se o sistema de irrigação por subcapilaridade, o substrato comercial 1 é recomendado para todos recipientes. O substrato comercial 2 somente deve ser empregado em bandejas alveoladas de 120 cm³.(AU)

In the production of citrus seedling, the knowledge of rootstock substrate and container is essential to define the entire substantial period to produce quality seedling. The objective of this research was to evaluate seedling emergence and vegetative development of six citrus rootstocks grown on two substrates and kept in different containers at the stage of sowing irrigated by capillarity. Two commercial substrates were tested and seeding was performed in three containers: stiff plastic tubes with 50cm³, stiff plastic tubes with 120cm³ and polystyrene trays containing 72 cells with a volume of 120cm³. The six rootstocks citrus evaluated were: Trifoliata [Poncirus trifoliata [L.] Raf.]; Flying Dragon [Poncirus trifoliata (L.) Raf. var. monstrosa]; Volkameriano lemon (Citrus volkameriana Pasq.), Fepagro C37 citrange [P. trifoliata x Citrus sinensis [L.] Osbeck.], Sunki tangerine (C. sunki hort. ex Tan.) and Swingle citrumelo (P. trifoliata x C. paradisi). The emergence, height and diameter of plants in the greenhouse were evaluated. Fresh weight, root and shoot dry weight, leaf number, leaf area per plant and leaf area per leaf were evaluated in the laboratory. In the evaluations of emergence of seedlings, the Sunki tangerine, Volkameriano lemon and Swingle citrumelo had higher rates compared to Trifoliata, Fepagro C37 citrange and Flying Dragon. When the system in a floating irrigation system, commercial substrate 1 is recommended for all containers. The commercial substrate 2 should be only used in alveolate trays of 120cm³.(AU)

Substratos e recipientes para a produção de porta-enxertos de citros irrigados por subcapilaridade / Substrates and containers for the citrus rootstocks' production irrigated by capillarity

O conhecimento do porta-enxerto, do substrato e do recipiente são fundamentais para a definição do período necessário para produzir mudas cítricas de qualidade. O objetivo deste trabalho foi avaliar a emergência de plântulas e o desenvolvimento vegetativo de seis porta-enxertos cítricos, cultivados em dois substratos e mantidos em diferentes recipientes, em sementeira, irrigados por subcapilaridade. Foram testados dois substratos comerciais e a semeadura foi realizada em tubetes com 50cm³, tubetes com 120cm³ e bandejas de isopor contendo 72 células com volume de 120cm³. Os seis porta-enxertos cítricos avaliados foram: Trifoliata [Poncirus trifoliata [L.] Raf.]; Flying Dragon [Poncirus trifoliata (L.) Raf. var. monstrosa]; limoeiro Volkameriano (Citrus volkameriana Pasq.), citrangeiro Fepagro C37 [P. trifoliata x Citrus sinensis [L.] Osbeck.], tangerineira Sunki (C. sunki hort. ex Tan.) e citrumeleiro Swingle (P. trifoliata x C. paradisi). Avaliou-se emergência, altura e diâmetro das plantas ao longo do cultivo em casa de vegetação. Em laboratório, avaliou-se massa fresca e seca da parte aérea e raiz, número de folhas, área foliar por folha e área foliar por planta. Nas avaliações de emergência de plântulas, a tangerineira Sunki, o limoeiro Volkameriano e o citrumeleiro Swingle apresentaram maiores taxas em relação ao Trifoliata, ao citrangeiro Fepagro C 37 e ao Flying Dragon. Ao empregar-se o sistema de irrigação por subcapilaridade, o substrato comercial 1 é recomendado para todos recipientes. O substrato comercial 2 somente deve ser empregado em bandejas alveoladas de 120 cm³.

In the production of citrus seedling, the knowledge of rootstock substrate and container is essential to define the entire substantial period to produce quality seedling. The objective of this research was to evaluate seedling emergence and vegetative development of six citrus rootstocks grown on two substrates and kept in different containers at the stage of sowing irrigated by capillarity. Two commercial substrates were tested and seeding was performed in three containers: stiff plastic tubes with 50cm³, stiff plastic tubes with 120cm³ and polystyrene trays containing 72 cells with a volume of 120cm³. The six rootstocks citrus evaluated were: Trifoliata [Poncirus trifoliata [L.] Raf.]; Flying Dragon [Poncirus trifoliata (L.) Raf. var. monstrosa]; Volkameriano lemon (Citrus volkameriana Pasq.), Fepagro C37 citrange [P. trifoliata x Citrus sinensis [L.] Osbeck.], Sunki tangerine (C. sunki hort. ex Tan.) and Swingle citrumelo (P. trifoliata x C. paradisi). The emergence, height and diameter of plants in the greenhouse were evaluated. Fresh weight, root and shoot dry weight, leaf number, leaf area per plant and leaf area per leaf were evaluated in the laboratory. In the evaluations of emergence of seedlings, the Sunki tangerine, Volkameriano lemon and Swingle citrumelo had higher rates compared to Trifoliata, Fepagro C37 citrange and Flying Dragon. When the system in a floating irrigation system, commercial substrate 1 is recommended for all containers. The commercial substrate 2 should be only used in alveolate trays of 120cm³.

Desempenho agronômico da cultura do nabo forrageiro influenciado pelos resíduos de plantas de girassol / Oil radish development agronomic affected by sunflower plants residues

O objetivo foi o de avaliar a emergência das plântulas, o crescimento das plantas, bem como a produtividade e a qualidade das sementes produzidas de nabo forrageiro (Raphanus sativus L.) influenciados pelos resíduos de plantas de girassol (Helianthus annus). Para isto, o delineamento experimental adotado foi o de blocos casualizados em parcelas subdivididas com quatro repetições. As parcelas foram representadas por área com e sem resíduos de plantas de girassol e, as subparcelas, por seis épocas de coleta (20, 40, 60, 80, 100 e 120 dias após a semeadura - DAS). Os resíduos de plantas de girassol não interferiram no estabelecimento das plântulas de nabo forrageiro, reduziram a produção de sementes por planta e favoreceram o vigor das sementes produzidas. Após 40 DAS, houve prejuízo ao desenvolvimento das plantas, à eficiência de translocação dos fotoassimilados e ao acúmulo de nutrientes de plantas de nabo forrageiro provenientes de área com resíduos de girassol.

The aim was to evaluate the seedling emergence, plant growth, seed yield and seed quality of oil radish (Raphanus sativus L.) influenced by the sunflower (Helianthus annus L.) plants residues. The experiment was randomized in split plot complete block with four replications. The plots were represented by the area with and without sunflower plants residues and the subplots, by the six sampling times (20, 40, 60, 80, 100 and 120 days after sowing - DAS). The sunflower plants residues did not affect seedling establishment in oilseed radish, reduced the seed yield per plant and favored the seed vigour. After 40 DAS, there was damage to the plant development, the efficiency of translocation of assimilates and nutrients accumulation in oil radish plants from area with sunflower residues.