Domestication of Lima Bean (Phaseolus lunatus) Changes the Microbial Communities in the Rhizosphere.

Plants modulate the soil microbiota and select a specific microbial community in the rhizosphere. However, plant domestication reduces genetic diversity, changes plant physiology, and could have an impact on the associated microbiome assembly. Here, we used 16S rRNA gene sequencing to assess the microbial community in the bulk soil and rhizosphere of wild, semi-domesticated, and domesticated genotypes of lima bean (Phaseolus lunatus), to investigate the effect of plant domestication on microbial community assembly. In general, rhizosphere communities were more diverse than bulk soil, but no differences were found among genotypes. Our results showed that the microbial community's structure was different from wild and semi-domesticated as compared to domesticated genotypes. The community similarity decreased 57.67% from wild to domesticated genotypes. In general, the most abundant phyla were Actinobacteria (21.9%), Proteobacteria (20.7%), Acidobacteria (14%), and Firmicutes (9.7%). Comparing the different genotypes, the analysis showed that Firmicutes (Bacillus) was abundant in the rhizosphere of the wild genotypes, while Acidobacteria dominated semi-domesticated plants, and Proteobacteria (including rhizobia) was enriched in domesticated P. lunatus rhizosphere. The domestication process also affected the microbial community network, in which the complexity of connections decreased from wild to domesticated genotypes in the rhizosphere. Together, our work showed that the domestication of P. lunatus shaped rhizosphere microbial communities from taxonomic to a functional level, changing the abundance of specific microbial groups and decreasing the complexity of interactions among them.

Genetically related genotypes of cowpea present similar bacterial community in the rhizosphere.

Plant breeding reduces the genetic diversity of plants and could influence the composition, structure, and diversity of the rhizosphere microbiome, selecting more homogeneous and specialized microbes. In this study, we used 16S rRNA sequencing to assess the bacterial community in the rhizosphere of different lines and modern cowpea cultivars, to investigate the effect of cowpea breeding on bacterial community assembly. Thus, two African lines (IT85F-2687 and IT82D-60) and two Brazilian cultivars (BRS-Guariba and BRS-Tumucumaque) of cowpea were assessed to verify if the generation advance and genetic breeding influence the bacterial community in the rhizosphere. No significant differences were found in the structure, richness, and diversity of bacterial community structure between the rhizosphere of the different cowpea genotypes, and only slight differences were found at the OTU level. The complexity of the co-occurrence network decreased from African lines to Brazilian cultivars. Regarding functional prediction, the core functions were significantly altered according to the genotypes. In general, African lines presented a more abundance of groups related to chemoheterotrophy, while the rhizosphere of the modern cultivars decreased functions related to cellulolysis. This study showed that the genetic breeding process affects the dynamics of the rhizosphere community, decreasing the complexity of interaction in one cultivar. As these cowpea genotypes are genetically related, it could suggest a new hypothesis of how genetic breeding of similar genotypes could influence the rhizosphere microbiome.

Genetic diversity and structure in natural populations of Cajui from Brazilian Cerrado

Cajui (Anacardium spp.) is a native fruit tree (small cashew) of the Brazilian Cerrado and possesses the potential for commercialization. However, cajui exploitation occurs exclusively through extractivism in the absence of conservation strategies. The lack of conservation strategies may lead to a decrease in genetic diversity of Anacardium. In this work, the genetic diversity and population structure of three natural populations in Sete Cidades National Park (PNSC; PI, Brazil) were assessed using ISSR analysis of 56 cajui accessions and two A. occidentale accessions (outgroup) from Pacajus (CE, Brazil). A total of 112 markers were obtained, 93 (83.04%) of which were polymorphic. The diversity indices of these populations indicated moderate levels of genetic diversity. According to AMOVA, 96.17% of the genetic variability lay within populations, with low genetic differentiation among populations (ΦST = 0.03828). Furthermore, STRUCTURE analysis indicated the existence of four connected genetic groups. The findings show that the individuals from the three collection sites did not represent different subpopulations, likely due to the high gene flow (Nm = 6.7) favored by the floral biology of Anacardium, pollinators and small-animal seed dispersers. This research identifies genetically divergent individuals (C-03, C-05, C-22, C-26, C-34 and C-39), which should be considered priority individuals for conservation and can inform conservation programs for Anacardium spp.

Phytotoxicity and cytogenotoxicity of composted tannery sludge.

Tannery sludge (TS) contains high levels of organic matter and chemical elements, mainly chromium (Cr). This can increase its toxicity, rendering it unsuitable for application to soil. However, composting has been proposed as an alternative method for detoxifying TS before its addition to soil. Thus, the aim of this study was to evaluate the phytotoxic and cytogenotoxic potential of untreated (TS) and composted (CTS) tannery sludge in solid and solubilized samples. Seed germination and root growth bioassays were performed with Lactuca sativa, while chromosomal aberrations were assessed using the Allium cepa bioassay. In solid samples, the L. sativa bioassay showed that TS adversely affected germination and root growth, while CTS had a negative affect only on root growth. In solubilized samples, only TS showed significant adverse effects on seed germination and root growth. In both solid and solubilized samples, TS and CTS showed cytotoxic, genotoxic, and mutagenic effects on A. cepa. Thus, results demonstrated that the composting of TS does not result in its complete detoxification. For this reason, TS and CTS cannot be recommended for agricultural use, since they may increase the risk of environmental contamination and crop damage.

Resistance of Lima Bean (Phaseolus lunatus L.) to the Red Spider Mite Tetranychus neocaledonicus (Acari: Tetranychidae).

The red spider mite, Tetranychus neocaledonicus (Acari: Tetranychidae) can be an important pest on lima bean (Phaseolus lunatus L.). Thus, the objective of this work was to assess the antibiosis and antixenosis effects of lima bean genotypes on T. neocaledonicus, through the evaluation of performance parameters as well as the host preference for food and oviposition. Nine lima bean genotypes from the Active Bank of Germplasm of the Federal University of Piauí - BGP / UFPI were screened. To assess antibiosis parameters, eggs of T. neocaledonicus were individually placed on leaf disks of each genotype. The period and survival of the different stages of development (larvae, protonymph, deutonymph and adult), pre-oviposition, oviposition and post-oviposition period, longevity and fecundity of females were evaluated, and fertility life table parameters were calculated. In choice tests, adult females of T. neocaledonicus were used. The numbers of mites and eggs were counted for each genotype. The protonymph, egg-adult, longevity and oviposition period, fertility life table parameters, as well as the food and oviposition preference were affected by lima bean genotypes. We found that some genotypes reduced adult female longevity, increased the larval and egg-adult period, decreased oviposition period, negatively affected the fertility life table parameters, reducing the net reproductive rate (Ro), the intrinsic rate of increase (rm) and the finite rate of increase (λ), while increasing the population doubling time (DT), exhibiting a reliable antibiosis effect upon T. neocaledonicus. Nevertheless, these same genotypes were the most preferred for food and oviposition. By contrast, some other genotypes reduced the adult female longevity and oviposition period, elongated the larval period and affected fertility life table parameters, demonstrating an antibiosis effect upon T. neocaledonicus. Moreover, these other genotypes were among the less preferred for food and oviposition, exhibiting an additional antixenosis effect. Thus, our results demonstrate that the genotypes of lima bean may present distinct levels of resistance to T. neocaledonicus, and this resistance may be an important tool for Integrated Pest Management. This is one of the first studies aiming to describe mite resistance sources in lima bean.

Protist species richness and soil microbiome complexity increase towards climax vegetation in the Brazilian Cerrado.

Biodiversity underlies ecosystem functioning. While aboveground biodiversity is often well studied, the belowground microbiome, in particular protists, remains largely unknown. Indeed, holistic insights into soil microbiome structures in natural soils, especially in hyperdiverse biomes such as the Brazilian Cerrado, remain unexplored. Here, we study the soil microbiome across four major vegetation zones of the Cerrado, ranging from grass-dominated to tree-dominated vegetation with a focus on protists. We show that protist taxon richness increases towards the tree-dominated climax vegetation. Early successional habitats consisting of primary grass vegetation host most potential plant pathogens and least animal parasites. Using network analyses combining protist with prokaryotic and fungal sequences, we show that microbiome complexity increases towards climax vegetation. Together, this suggests that protists are key microbiome components and that vegetation succession towards climax vegetation is stimulated by higher loads of animal and plant pathogens. At the same time, an increase in microbiome complexity towards climax vegetation might enhance system stability.

Agromorphological performance of garlic landraces in Piauí, Brazil / Desempenho agromorfológico de variedades crioulas de alho no Piauí

ABSTRACT: In garlic (Allium sativum L.), genotype evaluation facilitates the search for better varieties. The aim of this study was to use morphoagronomic traits to evaluate three garlic landraces, namely, “Cateto Roxo Local”, “Cateto Roxo Mineiro 1” and “Cateto Roxo Mineiro 2”. They were planted on May 1, 2014 and May 23, 2014, in the municipality of Sussuapara, State of Piauí, Brazil. These varieties have similar behavior at the vegetative stage. “Cateto Roxo Local” had the highest average bulb mass, clove number per bulb, and clove mass per bulb. “Cateto Roxo Mineiro 1” and “Cateto Roxo Mineiro 2” had the largest clove diameter per bulb. In Sussuapara - PI, “Cateto Roxo Mineiro 1” and “Cateto Roxo Mineiro 2” are recommended for planting in the beginning of May, whereas “Cateto Roxo Local” should be planted in the third week of May.

RESUMO: Na cultura do alho (Allium sativum L.), a atividade de avaliação de genótipos é importante na busca por variedades superiores e adaptadas. Nesse sentido, o objetivo do presente trabalho foi realizar avaliação agromorfológica em três variedades crioulas de alho, Cateto Roxo Local, Cateto Roxo Mineiro 1 e Cateto Roxo Mineiro 2, em duas épocas de plantio, 1o de maio e 23 de maio de 2014, no município de Sussuapara - Piauí. As variedades apresentam comportamento semelhante na fase vegetativa das plantas, considerando as duas épocas de plantio. Quanto aos caracteres relacionados à produção, Cateto Roxo Local apresentou maior média para massa de bulbos, número e massa de bulbilhos por bulbo, enquanto Cateto Roxo Mineiro 1 e Cateto Roxo Mineiro 2, se destacaram quanto ao diâmetro dos bulbilhos por bulbo. Cateto Roxo Mineiro 1 e 2 devem ser recomendadas para o plantio no início do mês de maio, enquanto para Cateto Roxo Local, o plantio pode ocorrer até a terceira semana de maio, em Sussuapara - PI.

Divergência genética em germoplasma de alho / Genetic diversity in garlic germplasm

RESUMO: O alho é uma das hortaliças mais importantes no mercado brasileiro e mundial. No Piauí, mais especificamente na microrregião de Picos, o alho semi-nobre foi cultivado em larga escala e supria a demanda de vários municípios do estado. Devido à entrada do alho nobre no mercado brasileiro, houve redução na produção de alho semi-nobre que pode ter levado à perda de diversidade genética. O objetivo deste trabalho foi estudar a diversidade genética em doze variedades de alho, sendo quatro de origem piauiense e oito da Coleção de Germoplasma de Alho da Escola Superior de Agricultura "Luiz de Queiroz" - Universidade de São Paulo (ESALQ/USP). Para isso, caracterizou-se o germoplasma com base nos descritores propostos pelo International Plant Genetic Resources Institute (IPGRI), atualmente Bioversity International, e realizou-se a genotipagem das variedades a partir de oito locos SSR. Os resultados obtidos com a análise morfológica corroboraram as análises moleculares, evidenciando complementaridade dessas dimensões de análise no estudo da diversidade genética em alho. Assim, conclui-se que existe divergência genética entre as variedades de alho estudadas em função da procedência do germoplasma e sugere-se que o material oriundo da ESALQ/USP trata-se de um germoplasma distinto do cultivado no Piauí. A divergência genética existente entre as variedades de alho no Piauí indica a possibilidade de seleção de genótipos superiores que aumentem a competitividade do alho piauiense frente ao alho importado.

ABSTRACT: Garlic is one of the most important crops in Brazil and in the world. In Piauí State, specifically in micro region of Picos, semi-noble garlic was once grown on a large scale and supplied the demand of various municipalities in the state. After the noble garlic was introduced to the Brazilian market, the production of semi-noble garlic reduced which may have led to loss of genetic diversity.This study investigated the genetic diversity in twelve varieties of garlic, four originally from Piauí State and eight from the Garlic Germplasm Collection of the College of Agricultura "Luiz de Queiroz" - Universidade de São Paulo (ESALQ / USP). The present study characterized the germplasm based on descriptions proposed by the International Plant Genetic Resources Institute (IPGRI), currently Bioversity International, and conducted the genotyping of varieties from eight SSR loci. The agronomic characters and microsatellite genotyping were efficient to estimate genetic diversity among the garlic varieties. The results obtained with the morphological analysis corroborated the molecular analyses, demonstrating complementarity of these analyses dimensions in the study of genetic diversity in garlic. Thus, we concluded that genetic diversity exists among the varieties of garlic studied in terms of the germplasm origin and suggests that the material from the ESALQ / USP is a germplasm distinct from that grown in Piauí State. The genetic divergence among varieties of garlic in Piauí State indicates the possibility of selecting superior genotypes that increase the competitiveness of garlic from Piauí State against imported garlic.

Potencial ornamental de acessos de pimenta / Potential for ornamental use of pepper accessions

O objetivo deste trabalho foi avaliar o potencial ornamental de dez acessos de pimenta Capsicum spp. procedentes da Coleção de Germoplasma da Universidade Federal do Piauí, Brasil. O experimento foi conduzido em casa de vegetação, no Departamento de Fitotecnia, do Centro de Ciências Agrárias, no município de Teresina, Piauí, obedecendo ao delineamento experimental inteiramente casualizado, com três repetições. Na caracterização morfoagronômica dos acessos, conforme orientação do Bioversity International, utilizaram-se os seguintes descritores qualitativos e quantitativos para o gênero Capsicum: forma da folha, hábito de crescimento da planta, antocianina no nó da planta, posição da flor, cor da corola, cor do fruto no estado intermediário e maduro, forma do fruto, forma do ápice do fruto, textura da epiderme do fruto, comprimento do fruto, comprimento do pedicelo, persistência do fruto maduro e altura da planta. Dentre os dez acessos avaliados, sete foram considerados com potencial ornamental: CGC-06 (C. chinense), CGC-07 (C. chinense), CGC-11 (C. annuum var. glabriusculum), CGC-23 (C. chinense), CGC-36 (C. annuum var. glabriusculum), CGC-59 (C. annuum var. glabriusculum) e CGC-67 (C. annuum var. glabriusculum). O CGC 11 apresentou estética mais harmoniosa, com flores eretas, as quais são de fácil percepção; frutos eretos e vistosos e folhas de formato lanceolado.

The objective of this research was to evaluate the potential for ornamental use of ten Capsicum spp. accessions from Germplasm Collection of Federal University of Piauí, Brazil The experiment was carried out in a greenhouse at the Department of Plant Science, Centre of Agricultural Sciences, in Teresina City, Piauí State, according to the completely randomized design, with three replications. In the morphoagronomic characterization of pepper accessions, according to Bioversity International, the following qualitative and quantitative descriptors for the Capsicum genus were used: leaf shape, plant growth habit, anthocyanin node of the plant, flower position, color of the corolla, fruit color and mature in the intermediate state, fruit shape, fruit shape of apex of the texture of the fruit skin , fruit length, length of pedicel, persistence of ripe fruit and plant height. Among the ten accessions, seven were considered with ornamental potential: CGC-06 (C. chinense), CGC-07 (C. chinense), CGC-11 (C. annuum var. glabriusculum), CGC-23 (C. chinense), CGC-36 (C. annuum var. glabriusculum), CGC-59 (C. annuum var. glabriusculum) and CGC-67 (C. annuum var. glabriusculum). The CGC 11 was the more harmonious aesthetic accession, by presenting erect flowers , which are easy to read; erect and showy fruits and lanceolate leaves format.

Herança de caracteres relacionados à arquitetura da planta em feijão-caupi / Inheritance of traits related to plant architecture in cowpea

O trabalho estudou o controle genético dos caracteres comprimento (CRP) e número de nós (NNRP) do ramo principal e hábito de crescimento em feijão-caupi, a partir dos cruzamentos TE96-282-22G x TVX-5058-09C e TE96-282-22G x IT81D-1332. O experimento foi conduzido na Embrapa Meio-Norte, em Teresina, PI, Brasil, no ano de 2003. Estimaram-se os componentes genéticos de média, variância e herdabilidades para os caracteres CRP e NNRP. O estudo da herança do hábito de crescimento foi realizado com base nas frequências dos fenótipos observados. Em ambos os cruzamentos, o modelo genético aditivo-dominante foi suficiente para explicar a variação fenotípica observada para o CRP e NNRP; os efeitos aditivos e de dominância são importantes no controle do CRP e NNRP, mas a variância aditiva é prevalente como componente genético. O CRP e NNRP apresentam controle oligogênico, associado com alta expressão do caráter. O hábito de crescimento apresenta herança monogênica, com dominância para o tipo indeterminado.

The aim of this study was to investigate the genetic control of traits related to plant architecture in cowpea: length and number of nodes on main stem, growth habit, from the crossings TE96-282-22G x TVX-5058-09C and TE96-282-22G x IT81D-1332. The experiment was conducted at Embrapa Mid-North, Teresina, PI, Brazil, in 2003. Experiments were carried out under randomized block design with four replications. Genetic components of mean and variance and heritability for the traits length and number of nodes on main stem were estimated. Growth habit was based on the frequencies of the phenotypes observed. In both crosses, the additive-dominant genetic model was sufficient to explain the phenotypic variation observed for length and number of nodes on main stem; additive and dominance effects are important in controlling the length and number of nodes on main stem, but the additive variance is prevalent as a component of genetic variance. Length and number of nodes on main stem presents oligogenic control associated with a high expression of trait. Growth habit has monogenic control, with dominance for the indeterminate type.

Emergência e crescimento inicial de plântulas de pimenta ornamental e celosia em substrato à base de composto de lodo de curtume / Germination and initial growth of ornamental Capsicum and Celosia in substrate of composted tannery sludge

Há grande potencial de uso dos resíduos industriais compostados como substrato na produção de mudas de espécies ornamentais. O objetivo deste trabalho foi avaliar a emergência e o crescimento inicial de plântulas de pimenta ornamental e celosia em substratos à base de composto de lodo de curtume. O experimento foi instalado em bandejas de isopor e os substratos utilizados foram: composto de lodo de curtume; composto de lodo de curtume + 10 por cento de vermiculita; composto de lodo de curtume + 20 por cento de vermiculita; substrato comercial à base de turfa, usado como controle. No composto de lodo de curtume, houve aumento na velocidade de emergência das plântulas apenas para pimenta ornamental. Para a fitomassa, a altura das plantas e para o comprimento das raízes, os maiores valores ocorreram nos tratamentos em que o substrato foi o composto de lodo de curtume, em relação à turfa. O maior valor de fitomassa das raízes foi obtido quando o substrato foi o composto de lodo de curtume associado com 10 por cento de vermiculita. O composto de lodo de curtume é uma alternativa potencial para uso como substrato na produção de mudas de pimenta ornamental e celosia.

For composted industrial wastes have high potential to use as substrate for seedling production of ornamental species, therefore that the aim of this work was to evaluate emergency and plant growth of ornamental Capsicum and Celosia in substrate based of tannery sludge compost. The experiment was carried out in trays and substrates were: tannery sludge compost, tannery sludge compost + 10 percent vermiculite, tannery sludge compost + 20 percent vermiculite, commercial substrate used as control. In the tannery sludge compost there was an increase in the rate of seedling emergence only for ornamental pepper. For the plant biomass, height and root length the highest values occurred in treatments where the substrate was tannery sludge compost as compared as with commercial substrate. The higher value of root biomass was obtained when the substrate was tannery sludge composted associated with 10 percent vermiculite. The tannery sludge compost may be a potential alternative for use as substrate in seedling production of ornamental Capsicum and celosia.

Diversidade genética entre acessos de espécies cultivadas de pimentas / Genetic diversity among accessions of cultivated peppers species

O conhecimento da diversidade genética entre acessos em bancos de germoplasma é importante para fins de conservação de recursos genéticos e uso em programas de melhoramento genético. Neste estudo, objetivou-se avaliar a divergência genética entre 23 acessos de pimentas do gênero Capsicum, a partir de sete descritores quantitativos e 19 qualitativos multicategóricos, com auxílio de técnicas multivariadas. Pela análise de variância, evidenciaram-se diferenças significativas entre os acessos de pimentas para todos os descritores quantitativos. Os coeficientes de variação (CV) do experimento variaram de 8,97 (LF) a 30,91 por cento (NFA). O Método de agrupamento de otimização via Tocher detectou a formação de oito grupos, tanto para descritores quantitativos, quanto para os qualitativos multicategóricos. Pelo Método UPGMA, formaram-se três grupos baseando-se nos descritores quantitativos e quatro grupos com base nos qualitativos. Há diversidade genética inter e intraespecífica no Banco de Germoplasma de Capsicum spp. da Universidade Federal do Piauí, com evidências de que não existem duplicatas entre os acessos estudados.

The knowledge of the genetic diversity among the accessions in germplasm banks it is important for the conservation of genetic resources and the use in breeding programs. This study aimed to evaluate the genetic divergence of 23 accessions of the genus Capsicum, and was based in seven quantitative and nineteen qualitative multicategorical descriptors and using multivariate techniques. The analyses of variance revealed significant difference (P<0.05) among the accessions of peppers for all quantitative descriptors. The coefficient variation ranged from 8,97 percent (LF) to 30,91 percent (NFA). The Tocher optimization method detected eight clusters for quantitative descriptors and also in as well as qualitative multicategoric descriptors. The UPGMA method detected three clusters for quantitative descriptors and four clusters within qualitative multicategoricdescriptors. There is genetic diversity inter and intraspecific in germplasm bank of Capsicum coming from The Federal University of Piauí, and these results indicate that there are not duplicated accessions.

Potencial produtivo de progênies de feijão-caupi com arquitetura ereta de planta / Potential grain yield of cowpea progenies with erect plant type

O objetivo foi estimarem-se parâmetros genéticos e identificarem-se, em populações de feijão-caupi, genótipos promissores quanto à produtividade de grãos e arquitetura ereta de planta. Três linhagens e 348 progênies de geração F3 e F2RC1, provenientes dos cruzamentos entre: TE96-282-22G (P1) x TVx5058-09C (P2) e TE96-282-22G (P1) x 1T81D-1332 (P3), foram avaliadas no Município de Teresina, PI, em 2004. A variabilidade genética apresentada para o comprimento e número de nós do ramo principal e para o número de vagens por planta indica condição favorável à seleção de progênies superiores quanto a esses caracteres. As populações que se destacaram quanto à produtividade de grãos, encontram-se entre as de maior comprimento e número de nós do ramo principal. A ausência de correlação entre o comprimento do ramo principal com o número de vagens por planta e o peso de cem grãos evidencia a possibilidade de seleção de genótipos com arquitetura moderna de planta, maior tamanho de sementes e produção de vagens.

This research was carried out to estimate genetic parameters and to identify, in cowpea populations, promising genotypes regarding grain yield and erect plant type. Three lines and 348 progenies, coming from advanced generations of crossings between: TE96-282-22G (P1) x TVx5058-09C (P2) and TE96-282-22G (P1) x 1T81D-1332 (P3), were evaluated in the Teresina, PI, in 2004. The genetic variability for the main branch node number, and for the number of pods per plant indicates favorable condition for selection of superior progenies, considering these characters. The populations that stood out for grain yield, are among those presenting higher length and number node in the main branche. The absence of correlation for the main branch length with number of pods per plant and with weight of a hundred grains indicates the possibility of selecting genotypes with erect plant type, higher seed size and pod production.

Repetibilidade e correlações entre caracteres morfo-agronômicos de cajazeira / Repeatability and correlations among yellow mombim morphoagronomical traits

Objetivou-se estimar os coeficientes de repetibilidade em quatorze cajazeiras (Spondias mombin L.), no município de Teresina, PI, utilizando-se o método de análise de variância; determinar o número de medições necessárias para predição do valor real dos indivíduos e os coeficientes de correlação fenotípica entre os caracteres: comprimento e largura da folha, número de folíolos por folha, peso da panícula, número de frutos por panícula, comprimento, diâmetro e peso do fruto, peso da semente, rendimento de polpa, teor de sólidos solúveis, acidez titulável, relação sólidos solúveis/acidez. Os genótipos diferiram com relação a todos os caracteres avaliados, indicando a presença de variabilidade genética. As estimativas dos coeficientes de repetibilidade expressaram maior estabilidade para peso do fruto, diâmetro do fruto, peso da semente, acidez titulável e relação sólidos solúveis/acidez titulável, indicando maior precisão na predição do valor real desses caracteres, nas cajazeiras. A avaliação de onze frutos é suficiente para predizer o valor real de todos os caracteres, com 90% de confiabilidade. A seleção para maior produtividade de frutos pode ser alcançada através da seleção indireta para caracteres relacionados à folha. Panícula mais pesada pode ser obtida pela seleção indireta de genótipos com sementes de menor peso.

The objective of this work was to estimate the coefficient of repeatability in fourteen yellow mombim (Spondias mombin L.), in Teresina, Piauí State, through the variance analysis method, in order to determine the number of measures necessary for an accurate prediction of the real genotype value and the correlation coefficients among the leaf length, leaf width, number of leaflets for leaf, panicles weight, number of fruits for panicles, fruit length, fruit diameter, fruit weight, seed weight, pulp revenue, soluble solid (SS), titrable acidity (AT) and SS/AT ratio. The genotypes had significant differences in all traits, indicating the existence of genetic variability. The estimates of the coefficients of repeatability expressed a greater stability for fruit weight, fruit diameter, seed weight, titrable acidity and soluble solid/titrable acidity ratio, indicating more accuracy to the real value pediction of these yellow mombim traits. The evaluation of eleven fruits is enough to predict the real value of all characters with an accuracy of 90%. The selection for characters related to the leaf could lead to an indirect selection for high fruit yield. The high panicle weight could be selected through the indirect selection for low seed weight.

Aspectos de biologia floral de cajueiros anão precoce e comum / Floral biology aspects of the early dwarf and common cashew

O conhecimento da biologia floral é de suma importância para o desenvolvimento da cultura do cajueiro (Anacardium occidentale L.). Com relação aos aspectos botânicos, as características morfológicas das flores contribuíram efetivamente para a determinação das espécies do gênero Anacarduim conhecidas. No presente trabalho, objetivou-se estudar a biologia floral dos cajueiros anão precoce e comum. A pesquisa foi desenvolvida na área experimental do Departamento de Fitotecnia, Centro de Ciências Agrárias, Universidade Federal do Piauí, em Teresina, PI, avaliando-se nove clones de cajueiro anão ("CAP 14", "Embrapa 09", "Embrapa 50", "Embrapa 51", "Embrapa 76", "Embrapa 183", "Embrapa 189", "FAGA 01", "FAGA 11") e um clone de cajueiro comum ("CCA"), utilizando-se quatro panículas por planta, cada uma com orientação norte, sul, leste e oeste. Os tipos varietais, cajueiro comum e anão precoce, apresentam pouca variação para a maioria dos caracteres avaliados. A proporção entre flores hermafroditas e o total de flores, em cajueiro comum, pode levá-lo a uma maior produção de frutos por panícula do que nos clones de cajueiro anão precoce analisados. O número de frutos desenvolvidos é bastante reduzido nos dois tipos varietais. As panículas situadas em diferentes orientações cardeais são semelhantes em todos os clones estudados quanto aos aspectos relacionados à biologia floral do cajueiro.

The knowledge of the floral biology is very important for the development of the cashew's culture (Anacardium occidentale L.). In relation to botanical aspects, the morphological characteristics of flowers contributed effective to determination of the well-known species of Anacardium. It was aimed at studing the floral biology of the early dwarf and common cashew. The research was developed in the experimental area of the Department of Fitotecnia, Centro de Ciências Agrárias, Universidade Federal do Piauí, in Teresina, PI, and nine clones of dwarf cajueiro ('CAP 14', 'Embrapa 09', 'Embrapa 50', 'Embrapa 51', 'Embrapa 76', 'Embrapa 183', 'Embrapa 189', 'FAGA 01', 'FAGA 11') and a clone of common cashew ('CCA'), were evaluated using four paniculae per plant, in north, south, east and west orientation. The varietal types, common and early dwarf cashew, present little variation for most of the evaluated characteristics. The common cashew presents a larger proportion between the number of hermaphrodite flowers and the total number of flowers than the early dwarf cashew clones; this may facilitate a larger production of fruits in the common cashew. The number of developed fruits is very low in both varietal types. The paniculae placed in different cardinal orientations are similar in all the clones in relation to the aspects related to the floral biology of the cashew.