Lenaldo Muniz de Oliveira

Effect of cytokinins on in vitro development of autotrophism and acclimatization of Annona glabra L.

The role of cytokinins in the differentiation of the photosynthetic apparatus in micropropagated plants and their effect on the plant’s ability to transition from a heterotrophic to an autotrophic condition during acclimatization was investigated. Annona glabra L. shoots were cultured on woody plant medium supplemented with sucrose and different cytokinins to evaluate leaf tissue for chloroplast development, chloroplast numbers, photosynthetic pigmentation, total photosynthetic potential, and soluble sugar content. Plants were transferred to the rooting medium in the presence or absence of sucrose and then acclimatized. Kinetin and benzyladenine (BAP) stimulated chloroplast differentiation. Inclusion of zeatin in the medium induced the formation of greater numbers of chloroplasts in the leaves, while plants cultivated in the presence of only kinetin and BAP demonstrated greater chlorophyll a and carotenoid content. The use of kinetin and BAP during in vitro culture promoted accumulation of dry matter during the acclimatization phase, especially in plants rooted under autotrophic conditions (without sucrose). Kinetin and BAP promoted development of more leaf area and greater plant survival rates in plant acclimatization on both autotrophic and heterotrophic media. The inhibitory effects of thidiazuron on the differentiation of chloroplasts, accumulation of chlorophyll a, and photosynthetic potential were examined.

Propagação vegetativa de Hyptis leucocephala Mart. ex Benth. e Hyptis platanifolia Mart. ex Benth. (Lamiaceae)

The genus Hyptis (Lamiaceae) has a special metabolism with remarkable variability and predominance of essential oils of great value to the various communities that use these plants due to their therapeutic properties. A number of studies on this genus have demonstrated that its essential oils present antimicrobial, antifungal, cytotoxic, anti-inflammatory, anti-HIV and insecticidal activities. However, few studies have focused on the sustainable exploitation of these species. The aim of this study was to evaluate the effect of different types of cuttings and different concentrations of indolebutyric acid (IBA) on the survival, growth and rooting rates of cuttings from Hyptis leucocephala Mart. ex Benth. and Hyptis platanifolia Mart. ex Benth., species endemic to the semi-arid region of Northeastern Brazil and with largely proven medicinal value. The experiment lasted four months. Apical, middle-apical, middle-basal and basal cuttings were treated with 0, 1000, 2000 and 4000 mg L-1 IBA solutions for 5 min. The use of apical, middle-apical and middle-basal cuttings induced by 2000 and 4000 mg L-1 IBA led to the best results for vegetative propagation of H. leucocephala. For H. platanifolia, the best results were obtained using middle-basal and basal cuttings treated with IBA at 2000 and 4000 mg L-1.

Caracterização física e química de bananas produzidas em sistemas de cultivo convencional e orgânico

The demand for organic fruit grows every year around the world and banana can show growth in this sector both in the domestic and in the foreigner market. However, there is a lack of information that supports the production of organic fruit and that confirms the advantages and disadvantages of the cropping systems. Thus, the purpose of this study was to evaluate bananas from conventional tillage and organic relation to physical aspects. It was used Caipira (AAA), Maravilha (AAAB), Pacovan Ken (AAAB), Prata Ana (AAB), Thap Maeo (AAB) and Tropical (AAAB) cultivars. Organic farming was used in green roof (Canavalia ensiformis and Arachis pintoi) and fertilization with organic compost, rock phosphate, castor bean and wood ashes. In conventional farming it was not used green cover, proceeding only the chemical fertilization with urea (100 kg ha-1), simple superphosphate (280 kg ha-1) and potassium chloride (540 kg ha-1).It was evaluate the physical attributes, number of fruit per bunch, diameter (cm) and fruit length (cm), shell thickness (mm) and chemical attributes, total soluble solids (TSS) pH, total acidity (TTA), humidity (H) and soluble sugar (reducing, non reducing and total). There were no significant differences between organic and conventional crops on these parameters, Tukey test at 5% probability. Virtually there were no differences in the characteristic of banana produced in the organic or traditional systems.

Efeito de meios de cultura, concentrações de GA3 e pH sobre a germinação in vitro de mangabeira (Hancornia speciosa Gomes)

A mangabeira (Hancornia speciosa Gomes) destaca-se por possuir um grande potencial como planta frutifera e produtora de borracha. As dificuldades encontradas no seu processo de propagacao por meio de sementes, devido, principalmente, a baixa taxa de germinacao e a recalcitrância, valorizam a busca por solucoes alternativas para a producao de mudas dessa especie, de maneira rapida e eficiente. Objetivou-se, neste trabalho, realizar o estudo da germinacao de sementes de mangabeira em condicoes in vitro, tendo como precedente a obtencao de explantes, para posterior utilizacao no cultivo in vitro. Neste estudo foram avaliados os efeitos de diferentes meios de cultura, concentracoes de sacarose e GA3 e de tres niveis de pH na germinacao da mangabeira. Frutos maduros foram coletados, passaram por processo de beneficiamento e tiveram suas sementes retiradas e utilizadas como explantes. Maior porcentagem de germinacao de sementes de mangabeira in vitro foi obtida com a utilizacao dos meios de cultura WPM e MS/2, suplementados com 15,0 g L-1 de sacarose, 0,2 mg L-1 de GA3 e com pH corrigido para 5,8.

Diazotrophic bacteria associated with sisal (Agave sisalana Perrine ex Engelm): potential for plant growth promotion

AimsIn the semi-arid region of Bahia State, Brazil, sisal (Agave sisalana Perrine ex Engelm) has been cultivated for fibre production for several decades without the use of chemical fertilizers. The contribution of biological nitrogen fixation (BNF) to this crop and the occurrence of diazotrophic rhizosphere, epiphytic or endophytic bacteria have not been investigated. The aims of this work were to study the occurrence and diversity of diazotrophic bacteria in rhizosphere soil, root and leaf tissues of sisal plants from this region, as well as to test their potential for plant growth promotion.MethodsBurk’s nitrogen free semi-solid medium was used for isolation and the MPN method was used for quantification of diazotrophic bacteria. BOX-A1R PCR and 16S rRNA sequence analyses were performed to study the diversity of bacterial isolates harboring the nifH-gene. Six isolates were selected for growth promotion of cucumber plants.ResultsA high diversity of BNF bacterial isolates was observed in sisal plants and rhizosphere soil. Bacterial populations were higher in roots, followed by soil and sisal leaves. Burkholderia, Leifsonia and Paenibacillus were the predominant genera. All isolates tested were able to promote cucumber growth.ConclusionsThis study showed that sisal-associated diazotrophic bacteria are diverse and may be further exploited to promote plant growth.

Effect of different culture tube caps and concentrations of activated charcoal and sucrose on in vitro growth and budding induction of Annona glabra L.

Este trabalho foi realizado com o objetivo de avaliar o efeito do tipo de selamento do recipiente de cultura e diferentes concentracoes de sacarose e carvao ativado na inducao e crescimento de brotacoes in vitro de Annona glabra L.; especie frutifera conhecida popularmente como araticum. Segmentos nodais obtidos de plantas de A. glabra mantidas em casa de vegetacao, apos o processo de assepsia, foram inoculados em meio de cultura WPM com 7 g L-1 de agar e sacarose (0,00; 29,21; 58,63 e 116,84 mM) combinado com carvao ativado (0,0 e 2,0 g L-1) e 250 mg L-1 de benomil. Avaliaram-se dois tipos de selamento nos tubos de ensaio: tampa com pelicula de PVC e tampao de algodao. O experimento foi instalado em DIC em arranjo fatorial 4x2x2, com 4 repeticoes/5 tubos por parcela. Avaliou-se o numero brotacoes, a porcentagem de explantes responsivos, o numero de folhas expandidas por brotacao, o comprimento da maior folha, a abscisao foliar, o comprimento e a materia seca das brotacoes. O tipo de selamento influenciou a organogenese em segmentos nodais de A. glabra. Contudo, nao houve inducao de brotacoes na ausencia de sacarose. O maior numero de folhas expandidas foi obtido quando utilizou-se 58,42 mM de sacarose em tubos selados com tampao de algodao e a abscisao foliar foi reduzida a metade na presenca do carvao ativado. Maiores comprimentos e maiores pesos da materia seca das brotacoes foram obtidos em tubos selados com tampao de algodao, tambem na presenca de carvao ativado.

Efeitos de citocininas sobre a anatomia foliar e o crescimento de Annona glabra L. durante o cultivo in vitro e ex vitro

The effect of different sources of cytokinins during the in vitro cultivation of A. glabra on anatomical characteristics of leaves and plant growth was evaluated in this work. BAP (6-benzilaminopurine) and KIN (kinetin) induced an increase in leaf mesophyll thickness, while the ZEA (zeatin) promoted an increase in density and stomatic index and development of leaves vascular system. The utilization of KIN and BAP improved higher plant development and survival rate during the acclimatization and rooting phases.

Effects of cytokinins on in vitro mineral accumulation and bud development in Annona glabra L.

Annona glabra e uma especie frutifera tropical que apresenta elevado potencial agronomico pelo fornecimento de frutos para o consumo in natura e pela producao de fitofarmacos. O cultivo in vitro tem sido preconizado como a forma mais adequada de propagacao para essa especie, embora sua utilizacao em larga escala ainda seja limitada pela elevada taxa de abscisao foliar, reduzida taxa de multiplicacao dos explantes e crescimento lento das brotacoes. Objetivou-se, neste trabalho, avaliar o efeito de citocininas sobre o acumulo de minerais nas brotacoes de A. glabra cultivadas in vitro e seus reflexos sobre o crescimento e sobrevivencia das plantas nesse tipo de ambiente. Brotacoes de A. glabra foram cultivadas em meio Wood Plant Medium (WPM), na presenca de 6-benzilaminopurina (BAP), thidiazuron (TDZ), cinetina (KIN) e zeatina (ZEA). A utilizacao de KIN e BAP induziu maior crescimento, maior acumulo de massa seca, maior desenvolvimento da area foliar e maior taxa de sobrevivencia das plantas durante o cultivo in vitro dessa especie. Todas as fontes de citocininas testadas estimularam maiores acumulos de nitrogenio e boro nas brotacoes e menores de calcio.

Efeito da fonte de carbono na multiplicação in vitro de Annona sp.

A familia Annonaceae compreende, aproximadamente, mais de 2.300 especies, algumas com ampla aceitacao no mercado nacional. No entanto, o plantio comercial tem sido prejudicado, em razao das questoes relacionadas a producao de mudas. Considerando que a micropropagacao e uma tecnica viavel nesse contexto, conduziu-se este trabalho, com o objetivo de avaliar o efeito de diferentes fontes de carbono na inducao de brotacoes in vitro em cinco especies de anonaceas. Segmentos nodais obtidos de plantas de Annona glabra, A. cauliflora, A. coriacea, A. bahiensis e Rollinia silvatica, foram inoculados em meio a cultura WPM solido + 8,87 μM de BAP, 0,86 mM de benomil e 87,64 mM das seguintes fontes de carbono: glucose, sucrose, fructose, galactose, sorbitol e maltose. Avaliou-se o numero de brotacoes, o comprimento e o peso da maior brotacao, o numero de folhas expandidas por brotacao, o comprimento da maior folha e a materia seca das brotacoes. Nao houve diferenca significativa entre as fontes de carbono para o numero de brotacoes. Mas, para as variaveis comprimento das brotacoes, numero de folhas expandidas, comprimento da maior folha e materia seca das brotacoes, tanto as especies estudadas como as fontes de carbono influenciaram significativamente as respostas, e os menores valores foram obtidos na presenca de sorbitol. Os resultados obtidos indicam que, exceto o sorbitol, qualquer carboidrato pode ser utilizado em protocolos de micropropagacao de A. bahiensis, A. cauliflora, A. coriacea, A. glabra e R. silvatica.

Seed morphology and post-seminal development of Physalis angulata L

Physalis angulata is also known as camapu, mullaca or jua-de-capote it belongs to the Solanaceae family. This species has its medicinal importance due to vitasteroids presence known as physalins, and currently due to its use as food. It propagates readily by seed, which is the reason why it is regarded as weeds in other crops. Accordingly, the identification of that species in the early stages of growth is indistinguishable from other weeds, hindering taxonomic characterization. Thus, the objective of this study was to morphologically characterize seeds and post-seminal development of Physalis angulata. The tests were developed in the Laboratory of Germination of the Experimental Unit/Nursery, in Feira de Santana/BA. Therefore, we have performed morphometric analysis of the seeds (4 replicates of 25 seeds) and we have analyzed their external and internal features with the aid of a stereoscopic microscope. For the description of the species seedlings it was used Petri dishes containing two sheets of filter paper (4 replicates of 20 seeds) and moistened with distilled water. The methodology for describing the post-seminal developmente was conduced under field conditions and consisted of evaluetions performed five days after sowing (inssuance of cotyledons) and the range of up to 15 days (and inssuing eophylls metaphylls) in which two replicates were used 20 pots. Assessments were performed five days after sowing (issuance of cotyledons) and ranging of up to 15 days (emission of eophylls and metaphylls). The seeds had an average of 1.55 mm long, 1.26 mm wide and 0.43 mm thick. The period of analysis was sufficient to characterize the seeds and seedlings of the species, applied as a criteria for abnormality.