7 research outputs found

    Seed germination and seedling emergence of velvetleaf (Abutilon theophrasti) and Barnyardgrass (Echinochloa crus-galli) Germinação de sementes e emergência de plântulas de Abutilon theophrasti e Echinochloa crus-galli

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    Abutilon theophrasti and Barnyardgrass (Echinochloa crus-galli) are major weeds that affect cropping systems worldwide. Laboratory and greenhouse studies were conducted to determine the effects of temperature, pH, water and salinity stress, and planting depth on seed germination and seedling emergence of Velvetleaf and Barnyardgrass. For Velvetleaf, the base, optimum and ceiling germination temperatures were estimated as 5, 35 and 48 ºC, respectively. Seed germination was sensitive to drought stress and completely inhibited by a potential of -0.6 MPa, but it was tolerant to salinity. Salinity stress up to 45 mM had no effect on the germination of Velvetleaf, but germination decreased with increasing salt concentration. Drought and salinity levels for 50% inhibition of maximum germination were -0.3 MPa and 110 mM, respectively. Seed germination of Velvetleaf was tolerant to a wide range of pH levels. For Barnyardgrass, the base, optimum and ceiling germination temperatures were estimated as 5, 38 and 45 ºC, respectively. Seed germination was tolerant to drought stress and completely inhibited by a potential of -1.0 MPa. Salinity stress up to 250 mM had no effect on seed germination. Drought and salinity levels for 50% inhibition of maximum germination were -0.5 MPa and 307 mM, respectively. A high percentage of seed germination was observed at pH=5 and decreased to 61.5% at acidic medium (pH 4) and to 11% at alkaline medium (pH 9). Maximum seedling emergence of Velvetleaf and Barnyardgrass occurred when the seeds were placed on the surface of the soil or at a depth of 1 cm.<br>Abutilon theophrastie Echinochloa crus-galli são as principais plantas daninhas que afetam os sistemas de cultivo em muitas partes do mundo. Estudos em laboratório e em casa de vegetação foram conduzidos para determinar os efeitos da temperatura, pH da água e estresse salino e da profundidade de semeadura na germinação e na emergência das plântulas de A. theophrasti e E. crus-galli. Para A. theophrasti, as temperaturas de base, ótima e de teto de germinação foram estimadas em 5, 35 e 48ºC, respectivamente. A germinação das sementes foi sensível ao estresse hídrico e inibida completamente por um potencial de -0,6 MPa, mas foi tolerante à salinidade. Estresse salino de até 45 mM não teve nenhum efeito sobre a germinação de A. theophrasti, porém esta diminuiu com o aumento da concentração salina. Os níveis de seca e de salinidade para 50% de inibição da germinação máxima foram de -0,3 MPa e 110 mM, respectivamente. A germinação das sementes de A. theophrasti foi tolerante a uma vasta gama de níveis de pH. Para E. crus-galli, as temperaturas de base, ótima e de teto de germinação foram estimadas em 5, 38 e 45ºC, respectivamente. A germinação das sementes foi tolerante ao estresse hídrico e inibida completamente a um potencial de -1,0 MPa. Estresse salino de até 250 mM não teve efeito sobre a germinação das sementes. Os níveis de seca e de salinidade para 50% de inibição da germinação máxima foram de -0,5 MPa e 307 mM, respectivamente. Elevada porcentagem de germinação das sementes foi observada a pH=5, com diminuição para 61% em meio ácido (pH=4) e para 11% em meio alcalino (pH=9). A máxima emergência das plântulas de A. theophrasti e E. crus-galli ocorreu quando as sementes foram colocadas sobre a superfície do solo ou a uma profundidade de 1 cm

    Therapeutic health benefits of religion among elderly-population based representative survey from Iran

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    Background: We determined whether practice of religious beliefs influence health-related lifestyle among general elderly population. Methods: We recruited elderly (60+years) subjects from among the general population who were invited to answer practice of religious belief and healthy lifestyle in Iranian elderly questionnaires. Results: A total of 218 elderly subjects participated (51.3 males, mean age: 68.3 years, SD 9.2, range 60-92). The mean religious belief was 73.0 (SD 11.5) without male-to-female difference (p=0.9). The mean lifestyle was 100.9 (SD 14.7, range 61-138) with a 9.3 male-to-female difference, p=0.0001. The odds of better lifestyle with religion was 5.5 (p=0.001, effect-size=0.18, variance=29.5). The most benefit was in prevention (effect-size 0.18), nutrition (effect-size 0.15), and social relationship (effect-size 0.12). Conclusions: Based on a representative un-selected validated sample, and by using a systematic questionnaire, and after controlling for various possible confounders, and within current evaluation limits, we may conclude that religion may mitigate health-related lifestyle. © 2020, Indian Journal of Forensic Medicine and Toxicology. All rights reserved
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