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1.
Artigo | IMSEAR | ID: sea-219314

RESUMO

Many species among shelled gastropods � either land snails or marine snails � exhibit determinate growth and, therefore, are expected to implement some regulating process aiming at limiting the impact on the final (adult) shell-size of the (possibly excessive) intraspecific variability in the rate of shell-development. Indeed, a usually more or less limited range of variation is allowed for adult shell-size, in those species having determinate growth. Mollusks are expected to be no exception in this respect and, up to now, the occurrence of such a regulating process has actually been reported systematically, despite a still too limited number of investigations. Yet, the question remained of the ability of this regulatory process to finely adjust the end of the final development of both body and shell (specifically in term of the final number of whorls), so as to limit the variations in adult shell-size, despite the amplitude of intraspecific variability in shell development rate. I provide here preliminary empirical evidence for such a 揻inely tuned� regulating process � the strength of which is mirrored by the degree of 揋ouldian� negative covariance between whorl growth-rate and the number of whorls at adulthood. As expected, the strength of the regulating process reveals systematically increasing (i) with the amplitude of the intraspecific variability in shell development-rate and (ii) with the narrowness of the range of variation allowed for the adult shell-size (narrowness which depends upon the identity of the particular species under consideration). In addition to the already reported usual occurrence of this regulating process among shelled gastropods, its 揻inely tuned� character provides here still further evidence as regards its major importance in controlling the species-specific adult body mass, and this even for typically soft-bodied animals.

2.
Chinese Traditional and Herbal Drugs ; (24): 1047-1051, 2015.
Artigo em Chinês | WPRIM | ID: wpr-854250

RESUMO

Objective: To explore the effect of different treatment on Codonopsis pilosula seed germination and seedling growth, and then find out the best treatment method. Methods: C. pilosula was pretreated by different methods, culture was carried out by thermostatic cultivation, and C. pilosula seed germination and seedling growth (30 d) were observed, then the data were analyzed with statistic. Results: Temperature and soil moisture had the significant impact on C. pilosula seed germination and seedling growth, the optimum temperature was 20-30℃, optimum humidity was 45%-75%. C. pilosula seed germination and seedling growth could be effectively promoted by potash treatment, chemicals at suitable concentration, and growth regulators. However, the growth regulators could change the seedling morphological characteristics, C. pilosula seed germination and seedling growth fast with potash treatment, plant was normal and has less disease. Conclusion: Potash treatment is beneficial to seed germination and seedling growth, so as to effectively improve the seedlings yield and quality. Potash treatment could be widely used in C. pilosula field seedling production.

3.
J Environ Biol ; 2010 Nov; 31(6): 939-944
Artigo em Inglês | IMSEAR | ID: sea-146518

RESUMO

This study assesses the effect of NaCl (80 and 160 mM) and CaCl2 (10 mM) solutions, alone and in combination, to 30-day-old seedlings of Cichorium intybus L. Observations were made at 30 day intervals from the time of treatment till harvest (180 days after sowing). Application of NaCl resulted in significant decreases in lengths of root and stem, in dry weights of root, stem and leaves and in the leaf area, as compared with control. The reduction was less with the combined application of NaCl and CaCl2 than with the NaCl treatment alone. On the contrary, treatment of CaCl2 alone promoted the above variables. Proline content in the leaves was enhanced with NaCl and CaCl2 alone as well as with the NaCl + CaCl2 treatments; the maximum (six-fold) enhancement was observed with the combined treatments, compared with NaCl (four-fold increase) and CaCl2 (two-fold increase) alone. The sodium (Na+) and Chloride (Cl) contents in different plant parts increased both with NaCl and with NaCl + CaCl2 treatments. The maximum accumulation was observed in leaves, followed by that in stem and root. The potassium (K+) and calcium (Ca2+) contents decreased under NaCl stress, but increased with CaCl2 treatment. Thus, calcium ameliorated the deleterious effects of NaCl stress and stimulated the plant metabolism and growth.

4.
Bol. latinoam. Caribe plantas med. aromát ; 9(4)jul. 2010. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-613279

RESUMO

Diamides are a class of metabolites that occurring in some Meliaceae plants, in Aglaia spp for example, with an ample body of biological activities, being insecticidal and herbicidal two of the most important. In our program of search for botanical pesticides, a series of N,N´-di-(4-R-phenyl)-alkanediamides was evaluated for its herbicidal activity. Many of the analogues tested exhibited moderate to good herbicidal activity both pre-emergence and post-emergence and have been found to inhibit energetic metabolism of pre-emergence weeds. The structure-activity relationships were probed by substitution on the benzene ring. Among the variations investigated, it was found that maximal herbicidal activity was obtained by substitution of –F, -CN and -Br at the aromatic portion and by n=2 of the aliphatic long chain. This last number of carbons (n=2) substitution was the key for the inhibitory activity.


Diamidas son una clase de metabolitos que estan presentes en plantas perteneciente a la familia de la Meliaceas, en Aglaia por ejemplo, poseen un amplio cuerpo de actividades biologicas, siendo la insecticida y la herbicida dos de las mas importantes. En nuestro programa para la busqueda de pesticidas botanicos, una serie de N,N’-di-(4-R-phenyl)-alkanodiamidas se evaluo para su actividad herbicida. Muchos de los analogos exhibieron desde buenas a moderadas actividades, tanto como pre-emergentes como post-emergentes y ademas se encontro que inhiben el metabolismo pre-emergente energetico de malezas. La relacion estructura-actividad fue probada por sustitución sobre al anillo aromatico. Entre las variaciones investigadas, se encontro que la maxima actividad herbicida se obtuvo por sustitución de F, CN y Br en la porcion aromatica y por n=2 del largo de la cadena alifatica. Este ultimo numero de carbonos de sustitución (n=2) fue clave para la actividad inhibitoria.


Assuntos
Diamida/farmacologia , Meliaceae/química , Plantas/crescimento & desenvolvimento , Plantas , Aglaia/química , Herbicidas/farmacologia , Lolium/crescimento & desenvolvimento , Lolium , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas , Reguladores de Crescimento de Plantas/farmacologia , Sementes/crescimento & desenvolvimento , Sementes
5.
Interciencia ; 33(7): 523-527, jul. 2008. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-630656

RESUMO

Different doses of Paclobutrazol (PBZ) combined with KNO3 were evaluated in order to determine their effect on flowering and fruit quality on two mango clones. The experiment was carried out at the INIFAP’s Cotaxtla Experimental Station in Veracruz, Mexico. A 14-year old orchard of Manila Cotaxtla 1 and Manila Cotaxtla 2 clones planted in 8×8m plots without irrigation was used. The experimental design was of random blocks in split plots. The eight treatments applied were: a) 0.0, b) 0.5, c) 1.0, d) 1.5, e) 2.0g a.i. PBZ per meter of canopy diameter, all combined with the application of 2% KNO3, f) 4% KNO3 without PBZ, g) 1.5g. a.i. PBZ, without KNO3, and h) control with neither product added. PBZ was applied on the soil and KNO3 in two applications on the foliage. The variables considered were number of panicles, fruit weight, fruit weight loss, total soluble solids (TSS), titratable acidity (TA) and firmness. PBZ and KNO3 application induced a larger number of advanced panicles in relation to the control, with higher values observed as PBZ dose increased. However, in total flowering there was no significant difference between treatments (p<0.05). PBZ did not have negative effects in the quality of fruit of neither cultivar. The treatments with higher doses of PBZ had higher content of TSS, less TA, less firmness and greater weight loss. Both cultivars were different in TA of the ripe fruits.


Se evaluaron diferentes dosis de paclobutrazol (PBZ) combinadas con KNO3 para determinar su efecto sobre floración y calidad de fruta en los clones de mango Manila Cotaxtla-1 y Manila Cotaxtla-2. El experimento fue realizado en el Campo Experimental Cotaxtla del INIFAP, en Veracruz, México. Ambos clones, de 14 años de edad, fueron plantados a 8×8m, sin riego. El diseño experimental utilizado fue de bloques al azar en parcelas divididas. Se aplicaron ocho tratamientos: a) 0,0; b) 0,5; c) 1,0; d) 1,5; y e) 2,0g i.a. por metro de diámetro de copa de PBZ, todos junto con aplicación de KNO3 al 2%; f) 4% KNO3 sin PBZ; g) 1,5g i.a. PBZ sin KNO3; y h) testigo sin PBZ ni KNO3. El PBZ fue aplicado al suelo y el KNO3 al follaje en dos aplicaciones. Las variables consideradas fueron número de panículas, peso de fruto, pérdida de peso del fruto, sólidos solubles totales (SST), acidez titulable (AT) y firmeza. La aplicación de PBZ y KNO3 promovió mayor número de panículas adelantadas con relación al testigo, con mayores valores al incrementar la dosis de PBZ; aunque en floración total no hubo diferencia significativa entre tratamientos (p<0,05). Los niveles de PBZ no tuvieron efecto negativo en la calidad de fruto en ambos cultivares. A mayor dosis de PBZ, hubo mayor contenido de SST, menor AT, menor firmeza y mayor pérdida de peso. Los cultivares mostraron diferencias en AT de los frutos maduros para consumo.


Avaliaram-se diferentes doses de paclobutrazol (PBZ) combinadas com KNO3 para determinar seu efeito sobre floração e qualidade de fruta nos clones de manga Manila Cotaxtla-1 e Manila Cotaxtla-2. O experimento foi realizado no Campo Experimental Cotaxtla do INIFAP, em Veracruz, México. Ambos os clones, de 14 anos de idade, foram plantados a 8×8m, sem regar. O desenho experimental utilizado foi de blocos aleatórios em parcelas divididas. Aplicaram-se oito tratamentos: a) 0,0; b) 0,5; c) 1,0; d) 1,5; e e) 2,0g i.a. por metro de diâmetro de copa de PBZ, todos junto com aplicação de KNO3 a 2%; f) 4% KNO3 sem PBZ; g) 1,5g i.a. PBZ sem KNO3; e h) testemunha sem PBZ nem KNO3. O PBZ foi aplicado ao solo e o KNO3 na folhagem em duas aplicações. As variáveis consideradas foram; número de panículas, peso do fruto, perda de peso do fruto, sólidos solúveis totais (SST), acidez titulável (AT) e firmeza. A aplicação de PBZ e KNO3 promoveu maior número de panículas adiantadas em relação à testemunha, com maiores valores ao incrementar a dose de PBZ; embora em floração total não houvesse diferença significativa entre tratamentos (p<0,05). Os níveis de PBZ não tiveram efeito negativo na qualidade do fruto em ambos os cultivares. Com maior dose de PBZ, houve maior conteúdo de SST, menor AT, menor firmeza e maior perda de peso. Os cultivares mostraram diferenças em AT dos frutos maduros para consumo.

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