Genetical analysis of a diallel cross in cowpea

Quatro cultivares de Caupi (Vigna unguiculata (L.) Walp) foram cruzadas em todas as combinações possíveis, incluindo os recíprocos. A análise genética foi feita segundo a metodologia de Hayman (1954), Mather & Jinks (1971) e Griffing (1956). As características estudadas foram: número de vagens por planta, comprimento da vagem, peso de 100 sementes e produção por planta. Os valores da heterose para a característica produção por planta variaram de 1,65 a 78,59% com uma média em torno de 34%. Dos quatro componentes da produção estudados, o caráter vagem por planta apresentou os maiores valores heteróticos (médios) variando de 0,22 a 43,80% e média igual a 18,67%. A variância genética não aditiva foi significativa para as características produção por planta e número de sementes por vagem, enquanto a variância genética aditiva foi observado para as características vagem por planta, comprimento da vagem e peso de 100 sementes.Four varieties of cowpea were crossed in all possible combinations, including the reciprocals. The genetic analysis was carried out according to the methodology of (Hayman 1954), Mather & Jinks (1971) and Griffing (1956). The characters studied were; number of pods per plant, pod length, weight of 100 seeds and yield per plant. The values of heterosis for yield per plant varied from 1.65 to 78.59% with a mean value of 34%. Of the four yield components studied, the character of pods per plant exhibited the highest values of heterosis, varying from 0.22 to 43.80% and a mean of 18.67. The non additive genetic variance was found to be significant for the characters such as the yield per plant, seed number per pod, while the additive genetic variance was observed in the case of pods per plant, pod length, and weight of 100 seeds

Simple and multiple resistances to viruses in cowpea genotypes

O objetivo deste trabalho foi identificar novas fontes de resistência simples e múltiplas em genótipos de feijoeiro caupi (Vigna unguiculata) a isolados de Cowpea severe mosaic virus (CPSMV), Cowpea aphid-borne mosaic virus (CABMV) and Cucumber mosaic virus (CMV). Trinta e três genótipos do Banco de Germoplasma da Universidade Federal do Ceará foram classificados quanto a sua resistência a quatro isolados de CPSMV, dois de CABMV e um de CMV. Após 25 dias da primeira inoculação dos isolados, todas as plantas que sofreram inoculação, incluindo as assintomáticas, foram testadas por meio de sorologia. Os genótipos foram classificados como: imune, plantas assintomáticas e sorologia negativa; resistentes, plantas com mosaico leve e sorologia positiva; suscetível, plantas com mosaico e sorologia positiva; altamente suscetível, plantas com mosaico severo, outros sintomas sistêmicos, como necrose sistêmica, e sorologia positiva. Foram identificadas fontes de resistência simples e múltipla às viroses, nos genótipos avaliados; no entanto, nenhum deles apresentou imunidade múltipla aos três vírus. Quatro genótipos apresentaram imunidade aos isolados de CPSMV, dois aos isolados de CABMV e dois ao CMV. Onze genótipos apresentaram resistência múltipla a dois vírus, o que possibilita o desenvolvimento de novas cultivares com resistência mais abrangente e estável. Os genótipos Purple Knuckle Hull-55, MNC-03-731C-21 e CNCx284-66E mostram resistência ao CABMV, mesmo após a inoculação do CMV.The objective of this work was to identify new sources of simple and multiple resistances to Cowpea severe mosaic virus (CPSMV), Cowpea aphid-borne mosaic virus (CABMV) and Cucumber mosaic virus (CMV) isolates in cowpea (Vigna unguiculata). Thirty-three genotypes from the germplasm bank of Universidade Federal do Ceará were tested as to their resistance to four CPSMV isolates, two CABMV isolates and one CMV isolate. Twenty-five days after the first virus inoculations, all inoculated plants, including the asymptomatic ones, were tested by serology. Genotypes were classified as: immune, plants without symptoms and negative serology; resistant, plants with mild mosaic and positive serology; susceptible, plants with mosaic and positive serology; and highly susceptible, plants with severe mosaic, other systemic symptoms, including systemic necrosis, and positive serology. Simple and multiple resistances to viruses were identified among the evaluated genotypes, but none of them showed multiple immunities to all isolates. Four genotypes showed immunity to all CPSMV isolates, two were immune to CABMV and two showed immunity to CMV. Eleven genotypes showed multiple resistances to two viruses, allowing for the development of new cultivars with more stable and broader resistance. Genotypes Purple Knuckle Hull-55, MNC-03-731C-21 and CNCx284-66E show resistance to CABMV, even when inoculated with CMV

GERMINAÇÃO DE SEMENTES DE MACAMBIRA (Bromelia laciniosa Mart. ex Schult)

Macambira is a bromélia used in the alimentation of man and domestic animals on Northeast of Brazilian, especially in times of drought. The study was conducted to evaluate at identifying breaking dormancy methods and verifying how temperature and light can affect germination of its seeds. In the first experiment, the seeds were treated the following treatments: immersion in acetone, in alcohol, to eter, hot water, wash in running water, dry cold and dry heat, aiming at breaking dormancy and control. Were determinate the percentage of germination, first count of germination, index of velocity of germination and the mean time of germination. In the second experiment, after treatment of immersion in acetone during 60 minutes, the seeds were germinated under the following conditions: continued light and 25 ºC constant; continued light and 30 ºC constant; continued light and 35 ºC constant; continued light and temperatures (35 ºC/8 h and 20 ºC/16 h); continued dark and 25 ºC constant; continued dark and 30 ºC constant; continued dark and 35 ºC constant; continued dark and temperatures (35 ºC/8 h and 20 ºC/16 h); alternation of light (dark/16 h and light/8 h) and temperature of 25 ºC constant; alternation of light (dark/16 h and light/8 h) and temperature of 30 ºC onstant; alternation of light (dark/16 h and light/8 h) and temperature of 35 ºC constant; alternation of light and temperature (dark/20 ºC/16 h and light/35 ºC/8 h) and alternation of light and temperature (dark/25 ºC/16 h and light/35 ºC/8 h). It follows that the immersion in acetone during 60 minutes was the treatment more efficient to promote the of vigor and germination of seeds. The seeds do not germinate in the light absence, behaving as fotoblásticas positive

EFEITO DA TEMPERATURA E DA LUZ NAS SEMENTES DE COPAIFERA LANGSDORFII DESF.

Copaifera langsdorfii is a typical tree species very important for restoration of degraded areas. This study evaluated the effect of different temperatures and light conditions on Copaifera seed germination. The applied treatments were the temperatures of 25ºC, 30ºC and 20-30ºC and three different light expositions (constant dark, 8h of light plus 16h of dark and constant light). The tested variables were percentage, velocity and average time of germination. The treatments consisted of 200 seeds, with four replications of 50 seeds each, sown on a Germitest towel paper and maintained for 28 days on germination chamber. The completely randomized design was used and the averages compared by Tukey test at 5% probability. Germination percentage was not influenced by the treatments. The constant temperatures of 25ºC or 30ºC, independently of light regime, promoted a higher rate of germination velocity and caused the reduction of the germination average time

Influência da temperatura e regime de luz na germinação de sementes de janaguba (Himatanthus drasticus (Mart.) Plumel.) Influence of temperature and light on the germination of janaguba (Himatanthus drasticus (Mart.) Plumel.) seeds

Com este trabalho, buscou-se determinar a influência da luz e da temperatura na germinação de sementes de janaguba. O ensaio foi conduzido no Laboratório de Análises de Sementes do Departamento de Fitotecnia, Universidade Federal do Ceará, Fortaleza-CE. Os tratamentos constaram de quatro temperaturas (20ºC, 25ºC, 30ºC e 20-35ºC) e três condições de luz (escuro constante, fotoperíodo de 8 h luz e 16 h escuro e luz constante). Foram utilizadas 200 sementes por tratamento, semeadas sobre papel de filtro dispostos em placas de Petri, e acondicionadas em câmara de germinação por 20 dias, para determinação do percentual, velocidade e tempo médio de germinação. Utilizou-se o delineamento inteiramente casualizado, com 4 repetições de 50 sementes, em esquema fatorial 3 x 4 (3 condições de luz e 4 temperaturas). As médias foram comparadas pelo teste de Tukey, a 5% de probabilidade. Houve diferença significativa na interação temperatura x luz, nas três variáveis. Concluiu-se que as sementes de janaguba apresentam fotoblastismo neutro; as temperaturas constantes de 20ºC e 25ºC, combinadas com escuro constante e luz/escuro, e as temperaturas constante de 30ºC e alternada de 20-35ºC, combinadas com luz/escuro, são as condições mais favoráveis à germinação; a combinação das temperaturas constantes de 25ºC e 30ºC e ausência de luz, aumenta a velocidade e reduz o tempo médio de germinação de sementes de janaguba.This study aimed to evaluate the influence of the temperature and light on the germinative behaviour of janaguba (Himatanthus drasticus)seeds, with the experiments being conducted at the Laboratory of Seed Analysis of the Federal University of Ceará. To analyse percentage, velocity and average time of germination, the treatments consisted of four different temperatures (20ºC, 25ºC, 30ºC e 20-35ºC) and three different light expositions (constant dark; 8 h of light plus 16 h of dark; and constant light). The treatments consisted of 200 seeds, with four repetitions of 50 seeds each, sown on a Germitest towel paper, displayed inside Petri dishes, and maintained for 20 days in germination chamber. A completely randomized 3x4 factorial design (three light expositions x four treatments) was used. The Tukey's Test at 5% of probability was used to compare the obtained averages. The janaguba seeds were shown to have neuter photoblastism. The better conditions for janaguma seed germination are temperatures of 20 and 25ºC combined with constant dark and light/dark, constant temperature of 30ºC and alternated temperature from 20 to 35ºC combined with intermittent light/dark. The constant temperatures of 25 and 30ºC plus constant dark led to the greatest indexes of velocity of germination and caused the reduction of the germination average time

Correlation and path analysis in components of grain yield of cowpea genotypes

This study aimed at verifying the effect of genotype x environment interaction on the relative contribution of yield components and final production of different cowpea genotypes. For this, data of yield components of 22 cowpea genotypes were evaluated in four environments in the State of Ceará. A one-way ANOVA tested the variability between genotypes and the Scott-Knott test compared the mean values of the genotypes. The correlations were estimated by a path analysis. A differentiated response from the genotypes to each environment was observed for all traits examined, indicating the need to perform the test for each situation separately. The number of pods per plant is the yield component with great potential of genetic gain in additional cycles of selection of more productive genotypes. The number of pods per plant and the number of grains per pod were the yield components with greater direct effects on the productivity

EVAPOTRANSPIRAÇÃO DO MARACUJÁ NAS CONDIÇÕES DO VALE DO CURU

Aiming on estimating the evapotranspiration (ETc) and crop coefficient (Kc) of passion fruit, an experiment was carried out at the Federal University of Ceará - UFC, The field experiment was carried out at the Curu Valley Experiment Station (FEVC) of the Federal University of Ceará, in Pentecoste - CE, during the period of May, 2004 to February, 2005. The evapotranspiration of the crop was estimated trough the law of conservation of masses using the water balance in a controlled volume of soil with a depth of 0.60 m. The period of the water balance was 296 days after transplanting (DAT). The results showed a variable increase of the accumulated the evapotranspiration during the cycle of the passion fruit plant went to the tension of 1,489.3 mm for 35 kPa. The evapotranspiration daily average in the tension was 35 kPa of 5.81mm day-1. The medium values in the crop coefficient were study for the 1.09Penman - Monteith - FAO and 0.88 Class A pan