Formosa Group Research Articles

Abordagem molecular em genitores elites de mamoeiro com foco na qualidade fisiológica das sementes

Abstract: Papaya seeds have natural barriers (phenolic compounds, seed structure and genetic factors) that make their germination difficult. And the use of seeds is the main means of propagating the species, whether for commercial cultivation, maintenance of germplasm or selection of genetic materials. Thus, the use of seeds with physiological quality (germination, normal seedlings and germination speed) is fundamental to the production of vigorous plants. However, few studies have been developed with the aim of evaluating and improving seed quality. From this perspective, the study aims to evaluate the quality of seeds in genetic materials widely used to obtain new genotypes, in order to identify superior materials and possible crosses between those that have high physiological seed quality. For this purpose, 44 genotypes were analyzed by molecular characterization, via microsatellite markers (observed and expected heterozygosity, number of alleles, information index, fixation index, inbreeding coefficient, genetic structure and genetic dissimilarity via UPGMA grouping), as well as determining physiological quality of the seed (germination speed index, percentage of germination and abnormal seedlings). Among the genotypes, 10 have germination above 60%, a high rate of germination speed and a low percentage of abnormal seedlings, and can be used in crosses to improve seed quality. The dissimilarity analysis was able to highlight the dissimilarity between the accessions of the Solo and Formosa groups. The use of the dissimilarity coefficient and the number of shared alleles made it possible to identify 18 possible crosses promising to improve the quality of papaya seeds.

Seleção de caracteres para programas de melhoramento genético do mamoeiro sob estresse hídrico e térmico

ABSTRACT Papaya cultivation is widespread in Brazil, particularly in the states of Bahia and Espírito Santo, where most commercial plantations are concentrated. Owing to the economic and social importance of papaya, the present study aimed to determine the explanatory variables between the genotypes of two cultivars: Golden (from the Soil group) and Tainung Nº 1 hybrid (from the Formosa group), cultivated under high temperatures and hydric stress. The genotypes containing more desirable agronomic characteristics were identified for use in plant genetic improvement programs. Principal component analysis (PCA) was applied to select the desirable genotypes for Golden and Tainung Nº 1 cultivars based on specific variables analyzed for two groups of variables; for group 1, the plant height, stem diameter, leaf length, leaf width, and leaf number were analyzed, whereas for group 2, the leaf and root dry mass, stem dry mass and fresh mass of 10 discs, fresh mass, and stem and root fresh mass were analyzed. When exposed to hydric and thermal stress, the Tainung Nº 1 cultivar outperformed the Golden cultivar for the evaluation characteristics selected for use in genetic improvement programs.

Sex type determination in papaya seeds and leaves using near infrared spectroscopy combined with multivariate techniques and machine learning

Papaya trees (Carica papaya L.) can bear female, hermaphrodite, and male flowers. However, only the hermaphrodite type produces elongate fruit required and appreciated by the consumer market. Sex type determination is carried out based on the plant phenotype after planting the seedlings, increasing the production costs. In this regard, the objective of this study was to verify the feasibility of using near infrared spectroscopy (NIR) as a non-destructive method for sexing papaya trees. The NIR spectra were collected using seeds and leaves of the respective seedlings of the cultivars ‘T2′, ‘Formosa’, and ‘Calimosa’ (Formosa group), and ‘THB’ and ‘Ouro’ (Solo group). By using the seeds, it was possible to obtain a F-score value of 0.81 for the external validation set applying the principal component analysis and quadratic discriminant analysis (PCA-QDA). By using the leaves, the F-score values was slightly lower (0.79) applying PCA and linear discriminant analysis (PCA-LDA). It was possible to use NIR spectroscopy associated with multivariate techniques as a non-destructive method to determine the sex types in papaya trees using both seeds and leaves of the seedlings.

MOLECULAR CHARACTERIZATION OF ELITE LINES OF PAPAYA (Carica papaya L.) VIA SSR MARKERS

This study aimed to analyze the genetic variability and to estimate diversity parameters of 23 elite papaya lines based on microsatellite molecular markers. The plant material was composed of elite lines, 18 from the 'Formosa' and five from the 'Solo' group. The expected heterozygosity (HE), observed heterozygosity (HO), and the coefficient of inbreeding (ƒ) for each genotype were estimated. The weighted index obtained the dissimilarity matrix, and the estimated genetic distance was presented graphically through the cluster analysis by the Ward method, as well as by the principal coordinates analysis (PCoA). The genotypes were also analyzed for genetic structure, using the Bayesian clustering method. Genetic variability was observed among the analyzed genotypes, mainly among the lines from the Formosa group. As for HO, four elite lines from the ‘Solo’ group had values equal to zero. However, the elite lines from the ‘Formosa’ group showed higher segregation in the loci with values ranging from 0.05 to 0.14. About ƒ, from the five lines in the 'Solo' group, four exhibited maximum fixation indexes for the analyzed loci, with the variation observed from 0.90 to 1.0, while the lines from the 'Formosa' group had a variation from 0.61 to 1.00. These results indicate the need for greater care in the process of obtaining inbreeding seeds to avoid pollen contamination, as well as the need to advance generations of self-fertilization with the lines from the 'Formosa' group to increase the level of inbreeding and ensure greater stability to hybrids that are developed from them.

Arbuscular mycorrhizal fungi as mitigating agents of salt stress in Formosa papaya seedlings

The objective of the present study was to evaluate the effect of mycorrhization on the nutritional, hydric and biochemical components of papaya seedlings, Carica papaia L., from the Formosa Group, Hybrid Tainung Nº 1, submitted to irrigation with saline water. The research was conducted at the Federal Institute of Paraíba, Sousa Campus, from March to December 2018. The experimental design used completely randomized blocks, with treatments arranged in a 4 x 5 factorial scheme, referring to the fungi species: Gigaspora candida, Acaulospora scrobiculata, Dentiscutata heterogama and without mycorrhizae, and the five salt concentrations in irrigation water: 0.0; 10.0; 20.0; 30.0 and 40.0 mmolc L-1 in four repetitions. The characteristics evaluated were: relative water content, water saturation deficit, membrane damage, photosynthetic pigments, concentration and accumulation of nitrogen, phosphorus, potassium, sodium and the relationship between potassium and sodium concentrations in leaf tissue. The species D. heterogama and G. candida presented the highest rates of leaf hydration and the lowest damage to biomembranes at all saline levels. Mycorrhizae increased the absorption of N and P, especially from 30 mmolc L-1 of salt. A greater relationship between potassium and sodium concentrations was evidenced in seedlings mycorrhized with D. heterogama.

Molecular sexing in papaya (Carica papaya L.) seeds based on endosperm DNA

Sex determination in papaya plants is a practice of great importance, given the greater commercial interest in hermaphrodite plants. This process is laborious, requiring plant three to five seedlings per hill since the sex types are identified by the flowers four months after planting. The objective of the present study was to perform sexing on papaya seeds through molecular markers by collecting a tissue sample for DNA extraction, without compromising seed germination. Two genotypes were used for the experiment: one of the Solo group (Golden) and another of the Formosa group (UC-01). Germination tests were performed to determine the best type of section (transverse and longitudinal) to remove the endosperm tissue associated with the best disinfestation treatment (fungicide or sodium hypochlorite) which would allow subsequent embryo development. For molecular sexing, six DNA extraction methods were tested in association with two amplification protocols. The association between the longitudinal section and the fungicide treatment provided a high germination percentage (81%) for the genotype of the Formosa group, which did not differ statistically from control (88%). The genotype of the Golden group also exhibited better germination in the longitudinal section treated with fungicide (32%), but the section led to a lower germination percentage than control treatment (82%). The PS2 primer was efficient in sexing the samples, as confirmed by phenotypic sexing. The present study unprecedently demonstrates sexing in Formosa standard papaya seeds via molecular markers, maintaining its germinative potential. For Solo seeds, which are smaller, adjustments should be made to the protocol.

Topcross hybrids in papaya: Genes derived from backcrossing provide resistance to multiple diseases

Papaya (Carica papaya L.) is widely cultivated and consumed in tropical and subtropical regions of the world. However, a number of diseases prevent the expansion of the crop, the two most prominent of which are ‘black spot’ and ‘phoma spot’. Considering the increasing market demand for fruits free of agrochemical residues, genetic resistance emerges a promising control measure. Our study proposes to estimate the specific combining ability and its interactions with the environment to identify genotypes with genetic resistance to black spot and phoma spot in topcross hybrids. This paper describes an experimental trial implemented in a randomized-block design with six replicates, involving 10 superior lines obtained by backcrossing; four elite lines (‘SS-72/12’, ‘JS-12’, ‘Sekati’ and ‘41/7’), used as parents of already registered genotypes; 20 topcross F1 hybrids (crosses between the 10 lines and the elite hybrids); and two commercial controls. The result related to non-additive interactions resulting from genetic complementation between parents. The SS 72/12 × 4 genotype, a hybrid of the Solo group, was identified as potentially resistant to both diseases. The Sekati × 1 and JS-12 × 17 genotypes, hybrids of the Formosa group, were also promising, given their negative estimates for incidence of black spot on the leaves and fruits and incidence and severity of phoma spot on the leaves, showing less damage when affected by diseases. These results enable the registration of potentially resistant cultivars with high-quality agronomic attributes, which can broaden the range of papaya cultivars sold in Brazil.

Physicochemical and sensory properties of papaya fruits of elite lines and hybrids

This study aimed to evaluate papaya elite lines and hybrids as to fruit physicochemical and sensory characteristics, thus identifying the most promising ones for the market. Fruits from improved genotypes of the Solo group (CMF H10.60, CMF L78, and UC 14) and Formosa group (CMF L10, UC 10, and UC 12) were evaluated, and the commercial cultivars Golden and Tainung nº 1 were used as controls. The following physical and physicochemical evaluations were performed: fruit length and diameter, fruit inner cavity diameter, fruit weight, fruit and pulp firmness, soluble solids, pH, titratable acidity, Ratio (soluble solids and titratable acidit relation), and firmness of peeled and unpeeled ripe fruits. Sensory tests were performed with 50 papaya consumers. In general, the improved genotypes of the Solo and Formosa groups showed similar physical and physicochemical characteristics to the Golden and Tainung n° 1 controls. The CMF L78 line of the Solo group and the UC10 hybrid of the Formosa group showed similar fruit firmness and ratio characteristics compared to both commercial cultivars. The three new genotypes in the Solo group showed superior sensory characteristics to the commercial cultivar Golden. The internal preference mapping of this group revealed a higher preference for the genotypes UC 14 and CMF L78, for having fruits with more intense color, stronger flavor, and firmer texture than the others. In the Formosa group, the UC 10 genotype outperformed the cultivar Tainung nº 1, with a global acceptance percentage of 96.15%, due to a more intense aroma, color, and flavor. The CMF L78 line of the Solo group and the UC 10 hybrid of the Formosa group have excellent physicochemical and sensory characteristics and are therefore promising alternatives to replace both commercial cultivars (Golden and Tainung nº 1).

Development of superior lines of papaya from the Formosa group using the pedigree method and REML/Blup procedure

ABSTRACT Developing superior lines based on a simultaneous response from many traits of agronomic importance is a fundamental strategy to expand papaya cultivar supply, mainly the much-needed cultivars belonging to group Formosa. Our goal was to associate the pedigree method with REML/Blup procedure to select plants of progenies F2:3 with superior agronomic performance. The variance components and genetic parameters were estimated using REML approach, and the genetic values were predicted using Blup methodology. The combined selection was performed using the IG2 selection index based on weights associated with agronomic values to indicate the best progenies and lines. The heritability estimates of progeny mean were high in most traits and evidenced significant genetic variability between progenies. The narrow-sense individual heritability was moderate in traits such as commercial fruits and soluble solid contents, which indicates a favorable condition for selections within progenies. The index was consistent in the selection of six superior progenies according to the assessed traits. This index also enabled promising genetic gains in traits of great interest such as yield and pulp thickness. Although the progenies are derived from self generations, they proved to be superior in traits of significant importance such as yield, commercial fruits, and pulp thickness when compared to the Tainung-01 hybrid, which is a worldwide-planted cultivar used as a reference to Formosa representatives. Six lines were selected within the superior progenies to continue the Formosa group-lines development program. The association of the pedigree method with REML/Blup procedure can be useful to assist breeders in an autogamous breeding program.

Evaluation of growth of papaya (Carica papaya L.) fruits in plants propagated from seeds and by grafting, as a result of the accumulated degree-days

An efficient way to study the development of papaya as a function of temperature is to relate it to the accumulation of heat, expressed in degree-days (DD), which has been used to estimate the amount of heat required for the growth and maturation of fruit. Temperature has a strong influence on the development of papaya fruits. We evaluated the growth in length and diameter in two different periods of the year (autumn/winter and spring/summer) in plants of three cultivars of papaya (‘Tainung 1’, ‘Golden’ and ‘Solo Sunrise’), some grafted and some propagated by seeds. According to the analysis of variance, there was a difference between the evaluation periods for autumn/winter and spring/summer. However, no significant difference for the different treatments within the same period of the year were found, within the same group of cultivars, the Solo and the Formosa groups, for the grafted and ungrafted plants. During autumn/winter, fruits took 175 days from anthesis to maturity, while in spring/summer, time maturity decreased to 112 days. The differences of climatic dry and wet seasons of the Mid-West region of Brazil make papaya production seasonal. The specific grafting processes in the evaluated papaya cultivars did not interfere with fruit development differently, but in grafted plants, fruit growth in the first load was slightly higher than in non-grafted plants, probably due to lower competition that these plants had to sustain at the beginning of cultivation and due to the greater availability of nutrients.

Path analysis under multicollinearity for papaya production of the solo and Formosa groups

Abstract Correlations and path analysis allow the understanding of the interrelations between characteristics of interest to the plant breeding. However, in order for their results to be reliable, the undesirable effect of multicollinearity must be excluded. The objective of this study was to estimate the correlations and their partitioning in direct and indirect effects, by path analysis, on the fruit production per plant (FP) of papaya from the heterotic Solo and Formosa groups, using two different strategies to circumvent multicollinearity. Eleven agronomic variables were evaluated in twelve papaya genotypes from the Solo group and nine from the Formosa group. Path analysis was obtained with the FP as the basic variable and to eliminate multicollinearity were used the discard of variables and the ridge path analysis. For the Solo group, fruit length and pulp thickness had greater direct effects on FP. In the Formosa group, the number of commercial fruits had a direct and indirect effect on FP. The two methodologies used to circumvent multicollinearity had high coefficient of determination, with better values for the ridge path analysis. The results indicated that the interrelation between the study characters was different in the Solo and Formosa groups. Thus, indirect selection strategies should be specific for each heterotic group.

Intrapopulation recurrent selection by mixed models in papaya of the formosa group

Abstract Few cultivars of papaya from the Formosa group are available to producers, and the development of new genotypes is indispensable. Thus, the use of effective selection strategies to obtain more productive cultivars and better quality fruits is also necessary. The aim of this study was to select of half-sib families (HSF) of papaya using the methodology of mixed models. Nineteen HSFs from the Incaper’s papaya breeding program were evaluated in a randomized block design with five replicates and nine plants per plot. The selection was made based on fruit mass (FM), pulp thickness (PT), soluble solids content in pulp (SS) and number of fruits (NF). The genetic parameters and genotypic values were estimated by the REML/BLUP procedure. The selected HSFs increased FM by 26.1%; the PT in 10.5%; the SS in 7.5% and; the NF in 13.0%. The additive heritability within the progenies and the individual variation coefficient obtained indicate that the selection between and within the HSFs can provide greater genetic gains. The selection based on the REML/BLUP methodology was efficient to obtain simultaneous genetic gains for all variables under study despite the negative correlation between them.

Towards reliable identification of male Dicerura: descriptions of three new and seven poorly known species in the Palearctic region (Diptera: Cecidomyiidae, Porricondylinae).

The taxonomy of Dicerura Kieffer, 1898, a genus of Porricondylinae now comprising 32 species in the Holarctic region, is revised. Three new species are described based on morphological characters of male adults: D. jakovlevi Jaschhof Spungis sp. nov. (from Finland), D. penttineni Jaschhof Spungis sp. nov. (Finland), and D. yezoensis Jaschhof Spungis sp. nov. (Japan). Dicerura padi Mamaev, 1975 syn. nov. is revealed to be a junior synonym of D. furculata Mamaev, 1968. Seven species, whose original descriptions are from a present-day perspective inadequate for the purpose of identification, are redescribed: D. barbata Mamaev, 1966; D. formosa Mamaev, 1998; D. foliicola Mamaev, 1968; D. furculata; D. iridis (Kaltenbach, 1873); D. stipator Mamaev, 1972; and D. unidentata Spungis, 1987. A key to males of Palearctic Dicerura is provided. New faunistic records are presented for D. barbata; D. complicata Spungis, 1987; D. dentata Spungis, 1979; D. formosa; D. fungicola (Mamaev, 1964); D. mixta Spungis, 1987; and D. unidentata. Male genitalic characters are shown to be useful to a certain extent for structuring the species diversity found within the genus Dicerura. The following groups of species are defined: iridis group (with nine species), dentata group (six species), fungicola group (four species), and formosa group (four species). Six of the species whose morphology is adequately known cannot be grouped within the proposed scheme, indicating the need for further character analysis and continuing search for yet undiscovered species that are assumed to exist in large numbers.

Productivity and quality of Formosa and Solo papaya over two harvest seasons

Abstract: The objective of this work was to evaluate the productivity and quality of papaya fruits (Carica papaya) of the Solo (12 genotypes) and Formosa (9 genotypes) heterotic groups over two harvest seasons. The experiment was conducted under field conditions in the municipality of Pinheiros, in the state of Espírito Santo, Brazil, in a randomized complete block design. Ten morpho-agronomic and physicochemical variables of the fruits were measured in winter (210-300 days after planting) and summer (450-540 days after planting). The data were subjected to the combined analysis of variance, to the breakdown of the genotype x environment interactions, and to the grouping of means by the Scott-Knott test. Although harvest season affected the evaluated characteristics, it did not alter the classification of the genotype. In the Solo group, the H 36-45 and UC 15 hybrids stand out due to their greater productivity, fruit weight, and soluble solids contents. In the Formosa group, the Rubi Incaper 511 cultivar shows greater productivity, higher number of commercial fruits, and lower number of deformed fruits over both evaluated harvest seasons.

Compostos bioativos e atividade antioxidante de variedades melhoradas de mamão

O objetivo deste trabalho foi determinar a concentração de carotenoides totais, vitamina C, polifenóis totais e a atividade antioxidante de variedades melhoradas de mamão. Foram avaliadas quatro variedades melhoradas pertencentes ao grupo Solo (L60, L47-05, L47-08 e H54.78), duas pertencentes ao grupo Formosa (L33 e H36.45) e as variedades comerciais Tainung no1 e Sunrise Solo. Dentre as variedades do grupo Solo, a linhagem L47-08 apresentou elevado teor de carotenoides totais e a variedade Sunrise Solo o maior conteúdo de vitamina C. Dentre as variedades do grupo Formosa, as variedades L33 e H36.45 apresentaram elevada atividade antioxidante, e maiores teores, respectivamente, de polifenóis totais e vitamina C do que a variedade comercial Tainung no1. Os polifenóis totais e a vitamina C apresentaram correlação significativa com a atividade antioxidante dos mamões avaliados

Avaliação físico-química e sensorial de frutos de genótipos melhorados de mamoeiro1

RESUMOA sustentabilidade e a expansão da cultura do mamoeiro dependem do desenvolvimento de genótipos com características superiores, para atender às demandas dos agricultores. Este estudo objetivou avaliar frutos de mamoeiro, quanto às características físico-químicas e sensoriais, visando a identificar novos genótipos com potencial para o mercado. Foram avaliados frutos de genótipos melhorados do grupo Solo (L60, L47-05, L47-08 e H54.78) e do grupo Formosa (L33 e H36.45) e as variedades comerciais Tainung nº 1 e Sunrise Solo. Analisouse o rendimento de polpa, peso, comprimento, diâmetro (fruto e cavidade interna) e firmeza e cor da polpa, além das avaliações sensoriais. As linhagens L47-05 e L47-08, do grupo Solo, apresentaram os maiores valores para peso (838,30 g e 803,94 g, respectivamente) e firmeza de fruto (8,35 kgf cm-2 e 7,74 kgf cm-2, respectivamente), portanto, são mais resistentes a injúrias mecânicas. A cultivar Tainung nº 1 apresentou os maiores valores para peso (842,77 g), comprimento (20,76 cm) e diâmetro (9,70 cm). Os genótipos do grupo Solo L47-05, L47-08, H54.78 e a testemunha Sunrise Solo apresentaram teor de sólidos solúveis acima de 14 ºBrix. A aceitação do híbrido H54.78 foi estatisticamente igual à da testemunha Sunrise Solo para todos os atributos sensoriais avaliados. Os genótipos H36.45 e L33, do grupo Formosa, foram estatisticamente iguais à testemunha Tainung nº 1 para todos os atributos. Com base na qualidade dos frutos, os genótipos H54.78 (grupo Solo) e H36.45 e L33 (grupo Formosa) são os mais promissores para o mercado e podem competir com as cultivares comerciais Sunrise Solo e Tainung nº 1.

Caracterização físico-química de frutos de novos híbridos e linhagens de mamoeiro

O objetivo deste trabalho foi avaliar genótipos de mamoeiro quanto às suas características físicas e físico-químicas, para identificar os mais promissores como novas cultivares comerciais. Foram realizadas análises de comprimento, diâmetro, diâmetro da cavidade interna, massa do fruto, espessura da polpa, firmeza do fruto com casca, firmeza da polpa, cor da polpa, acidez titulável, sólidos solúveis, pH, carotenoides totais e vitamina C em 22 genótipos. Observou-se variação significativa entre os genótipos para as características comprimento e massa dos frutos. Em relação à firmeza dos frutos com casca, 12 genótipos apresentaram firmeza superior à das cultivares comerciais Tainung No 1 e Sunrise Solo. A análise de correlação indicou que frutos com maior comprimento, diâmetro e diâmetro da cavidade interna tendem a apresentar maior peso e espessura de polpa, enquanto frutos com maiores teores de sólidos solúveis tendem a apresentar maior razão sólidos solúveis/acidez titulável, vitamina C e carotenoides totais. A linhagem L72, do grupo Solo, e o híbrido H36.45, do grupo Formosa, apresentam frutos com características físicas e físico-químicas semelhantes ou superiores às das cultivares comerciais Sunrise Solo e Tainung No 1, respectivamente, e, portanto, são promissoras para o mercado.

Influence of silicon in papaya plant growth

Study on the effect of foliar fertilization with silicon on the growth and dry matter accumulation of papaya plants. The experiment was conducted under greenhouse conditions from December 2012 to March 2013. The treatments consisted of five concentrations of silicon (0 (control); 1; 2; 3 and 4 mL L -1 ) applied to papaya leaves in a completely randomized design and four replications, totaling 20 experimental units. The genotype of papaya Tainung-1 (Formosa group) was used, which was grown for 90 days after sowing and received three foliar fertilization with silicon at 45, 60 and 75 days after sowing. Foliar fertilization with potassium silicate concentrations resulted in papaya plants more vigorous, with less stress to biotic and abiotic factors in this experiment. The concentration of 2.2 mL L -1 silicon on average promoted better growth and dry matter accumulation in roots of papaya plants.

Análise dialélica em mamoeiro para resistência a mancha-de-phoma

A resistência genética constitui alternativa sustentável para o controle da mancha-de-phoma na cultura do mamoeiro. No entanto, estudos básicos são necessários para a escolha de genitores e combinações híbridas resistentes à doença. Neste trabalho, por meio de cruzamento dialélico, envolvendo oito genótipos de mamão, quatro do grupo Solo e quatro do grupo Formosa, estimou-se a capacidade geral e específica de combinações híbridas quanto à resistência a mancha-de-phoma. Os genitores, bem com os híbridos obtidos dos cruzamentos foram avaliados em blocos casualizados, com quatro repetições. Quantificaram-se em duas épocas, março e maio de 2010, as severidades de mancha-de-phoma em folha, com auxílio de escala diagramática. Os genótipos Maradol JS12-N, Sekati e São Mateus demonstram melhor capacidade geral de combinação. Os híbridos Maradol x Golden, Maradol x Sunrise Solo 72/12, JS12-N x Golden, JS12-4 x Waimanalo, Sekati x Waimanalo, Waimanalo x Golden, Waimanalo x São Mateus, Golden x Sunrise Solo 72/12 e Golden x São Mateus apresentaram resultados promissores para seleção quanto à resistência à doença, com valores negativos de capacidade específica de combinação para severidade de mancha-de-phoma.

(The Period from the Ex-Dividend Date to the Payment Date and Corporate Financial Flexibility)

Chinese Abstract: 本文分析台灣股市2002至2006年之現金股息發放資料，發現除息日至發放日之間隔天數分布於6至155日；而且，全體市場之間隔天數有逐年增加之現象。持續檢視2007至2009年之發放資料後，發現上述現象顯著改善，主要原因是台塑集團改變股息發放政策。本研究估計台塑集團因此項政策改變，而導致$1.61億之利息收入機會成本，但投資人權益卻獲得改善。本研究再分析樣本公司之財務報表資料，發現集團別是間隔天數長短之主要決定因素，而且間隔天數與公司財務彈性（現金與約當現金除以總資產）呈現顯著負相關。此發現證明財務彈性與股息發放政策存在互動關係，且符合自由現金流量假說的廣義解讀。本研究也說明：部分發放公司遵循一致且穩定的短間隔天數政策，呈現重視股東權益之發放模式。 English Abstract: This article analyzes the cash dividend distribution of firms in the Taiwan stock market between 2002 and 2009. The duration between the ex-dividend date and the payment date is between 6 and 155 days. The dividends-weighted average periods increased gradually between 2002 and 2006. However, it decreased between 2007 and 2009. This is due to a change in the Formosa Group’s dividend payment policy. The change incurred a potential opportunity cost of TW$ 161 million of interest revenue to the Formosa Group. On the other hand, investors have benefited from this policy change. This study examines both the dividend policy and the financial position. In addition to finding the group identification factor is closely related to the period between the ex-dividend date and the payment date, we discovered the period correlated negatively to the level of financial flexibility (cash/asset). This evidence supports the view that financial flexibility matters in the short run. These findings are in line with the spirit of the free-cash-flow hypotheses. We also document evidence that some firms follow a policy of short and consistent periods between the ex-dividend date and the payment date, which benefits the shareholder.