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ABSTRACT The objective this study was to identify differences in the morphogenic patterns of four Urochloa brizantha cultivars (marandu, piatã, xaraés and paiaguás grasses) during the stockpiling period. A completely randomized design was used, with three replications, in experimental plots of 9m². The evaluations took place over 2 years. The grasses were stockpiled for 92 (Year 1) and 95 (Year 2) days. The leaf appearance rate of paiaguás grass was higher, compared to other grasses. In Year 1, the stem elongation rate of xaraés grass was higher than other grasses. At the end of stockpiling period of Year 1, the tiller population density (TPD) was higher in the paiaguás grass, intermediate in the xaraés and marandu grasses and lower in the piatã grass. At the end of the stockpiling period in Year 2, TPD was higher in the paiaguás grass canopy, intermediate in the marandu and piatã grasses canopies, and lower in the xaraés grass canopy. Paiaguás grass has greater leaf growth during the stockpiling period and is therefore suitable for use under stockpiled grazing. Xaraés grass has high stem elongation during the stockpiling period, which is why its use under stockpiled grazing must be accompanied by adjustments in pasture management.

Copyright of Revista Agrotecnologia is the property of Universidade Estadual de Goias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Agrotecnologia is the property of Universidade Estadual de Goias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to evaluate the effect of different concentrations of vermicompost slurry on the growth of leaf cabbage seedlings, applied on a substrate based on the decomposed babaçu stem. The experiment was conducted in a completely randomized design with four treatments and four replicates. The treatments were constituted by four doses of vermicompost slurry in different concentrations, where: T1: 0; T2: 50; T3: 100 and T4: 150 ml L-1, applied directly to the substrate. The following variables were evaluated: leaf number, plant height, neck diameter, plant height / neck diameter ratio, root length, root volume, fresh root and shoot mass, dry root and shoot mass and Dickson quality index. The results of the analysis of variance showed a significant effect (p ≤ 0.05) of the vermicompost slurry concentrations on the results of all variables studied, presenting the best results for the concentration of 100 and 150 ml L-1. The treatments with 100 and 150 ml L-1 of vermicompost slurry are the most indicated to potentiate the growth of leaf cabbage seedlings. The most economical dose of 100 mL L-1 is recommended. [ABSTRACT FROM AUTHOR]

ABSTRACT: Black shading nets are widely used in the protected cultivation of vegetables as a technique for controlling light and temperature, while the colored shading nets, with special optical properties to improve the use of solar radiation, appeared recently in the agricultural plastics market. Light quality transmitted by gray, aluminized, pearl, blue, red and black (control) nets with 30% shade was evaluated, as well as its effects on photosynthetic properties and fruits production of cucumber plants. Treatments (shade nets) were established under a randomized complete block design with four repetitions. The red net transmitted 23.7 and 40.3% more photosynthetic photon flux density (400 to 700nm) and red light (600 to 700nm) and the blue net transmitted 36% more blue light (400 to 500nm) in comparison with the respective transmissions of black net. All nets increased the photosynthetic responses: transpiration, stomatal conductance and CO2 assimilation, observed in plants grown under black net. Leaf greenness (41.6 SPAD units) and foliar area (90dm2) increased 22.8 and 38.9% with the red net, while the dry weight of leaf (52.5g) increased 21.9% with pearl net. Pearl, red, aluminized and blue nets showed to be viable alternatives because the production of fruit increased in 71, 48, 46 and 46%, respectively, in comparison with the conventional black net (52t ha-1).

The water restriction conditions in the Brazilian semiarid region are one of the most limiting factors to the establishment and yield of forage grasses. This study aimed to evaluate the effect of different irrigation regimes on morphogenetic, structural and productive traits of buffel grass. Arandomized blocks design, with five treatments and six replications, was used. Treatments consisted of five irrigation regimes, corresponding to the intervals of 2, 4, 6, 8 and 10 days. The traits analyzed were: leaf emergence rate, phyllochron, leaf and stem elongation rate, leaf senescence rate, final leaf length, number of green leaves per tiller, number of tillers, stem height, leaf/stem ratio, leaf area index, dry mass of green leaf and stem, dry mass of green, dead and total forage, root dry mass, dry mass and green dry mass/dead dry mass ratio. The final leaf length and dead forage dry mass were not affected by the irrigation regimes. The leaf/stem ratio followed a quadratic model, maintaining the value of 0.51 up to the irrigation regime of four days. The other morphological, structural and productive traits decreased linearly with increasing irrigation frequencies. The irrigation intervals promoted reductions in the morphological, structural and productive parameters of buffel grass, when grown under greenhouse conditions. The irrigation regime of 2 days stands out as the least restrictive to the development of buffel grass.

O estudo do desenvolvimento foliar é de grande importância para a avaliação do crescimento e desenvolvimento das plantas. O objetivo deste trabalho foi quantificar as consequências dos diferentes níveis do manejo de água de irrigação sobre o crescimento foliar e o número de folhas do Kalanchoe. O delineamento experimental utilizado foi inteiramente casualizado, com oito tratamentos de irrigação (15; 13; 11; 9; 8; 6; 4 e 2mm) e dez repetições. A área foliar das plantas foi calculada por meio do produto do comprimento e da largura de cada folha, multiplicada pelo coeficiente de 1,1134. Os resultados mostraram que as lâminas de irrigação entre 6 e 9mm apresentaram maior crescimento foliar e maior número de folhas por planta. A máxima eficiência técnica foi encontrada com lâminas de 6,68 e 8,59mm, para área foliar e número de folhas por planta, respectivamente. Em condições de déficit hídrico, o Kalanchoe reduz expressivamente sua elongação foliar transversal em relação à longitudinal.The research about the leaf development is very important to evaluate the plants growth and development. The objective of this research was to verify the different level consequences about the irrigation water manner in the leaf growth and the number of the Kalanchoe leaves. The experimental search used was completely randomized, with eight treatments, they consisted in 15; 13; 11; 9; 8; 6; 4 e 2mm irrigation in ten repetitions. The plants leaf area was calculated by the area of each leaf, multiplied by the coefficient of 1.1134. The results showed that the irrigation length between 6 and 9mm showed a bigger leaf growth and more leaves in each plant; the biggest technical efficiency was found with 6.68 and 8.59mm length, to each leaf area and the leaves number in leaf/plant, respectively. In a water condition deficit the Kalanchoe reduces a lot the leaf transversal growth related to the longitudinal.

O experimento foi realizado no período de dezembro de 2002 a abril de 2003, com o objetivo de avaliar, em capim-mombaça, o efeito de duas fontes de fósforo (superfosfato simples + superfosfato triplo e termofosfato magnesiano YoorinÒ), em função dos dias (24) e da época de avaliação (verão e outono), sobre intervalo (IAPF) e taxas de aparecimento (TAPF), alongamento (TALF) e total de folhas senescentes (TFS), altura da primeira (HPLIG) e da última lígula (HULIG) e número de folhas expandidas (NFEX), em expansão (NFE), total de folhas (NTF) e total de folhas vivas (NTFV). O delineamento experimental utilizado foi em blocos ao acaso com três repetições. Entre as variáveis avaliadas, somente a taxa de alongamento foliar foi maior para os perfilhos adubados com o SFS+SFT. Diferenças foram encontradas para a época de avaliação, em que o verão apresentou maiores TALF, HPLIG e HULIG. Os dias de avaliação realizados nos períodos do verão e outono apresentaram efeito para HPLIG, NFEX e NFE, NTF, NTFV, TFS. Para a interação dias × época, somente para o NTFV e TFS houve correlações lineares positivas. As fontes de fósforo não influenciaram a morfogênese do capim-mombaça, exceto o alongamento foliar, no qual o tratamento SFS + SFT - fósforo solúvel promoveu maior aumento que Yoorin ®. No verão, as plantas apresentaram maior crescimento dos perfílhos e de sua taxa de alongamento foliar que no outono.The experiment was carried out from December/2002 to April/2003 and aimed to evaluate the effects of two phosphorus sources (ordinary superphosphate + triple superphosphate and Yoorinâ magnesium thermophosphate), as a function of days (24) and evaluation period (summer and autumn) on leaf appearance interval (LAPI), leaf elongation rate (LER), leaf senescence (TLS), first and last ligule height (FLH; LLH), number of expanded leaves (NEL), number of leaves in expansion (NLE), total number of leaves (TNL), total number of live leaves (TNLL), and grazing return rate (GRR) on mombaçagrass (Panicum maximum Jacq. cv. Mombaça). The experimental design was randomized blocks with three replications. There was no difference between phosphorus sources in all evaluated variables, except for leaf elongation rate, which was higher in tillers fertilized with the SPS+TSP treatment. Differences were found between evaluation periods, with summer showing higher leaf elongation rate and ligule height (first and last). The days evaluated indicated effect on first ligule height (FLH; LLH), number of expanded leaves (NEL), number of leaves in expansion (NFE), total number of leaves (TNL), total number of live leaves (TNLL), total number of senescent leaves (TLS), and grazing return rate (GRR). For days and period interactions only TNLL and TSL had positive linear correlations.

Response functions used in crop simulation models are usually different for different physiological processes and cultivars, resulting in many unknown coefficients in the response functions. This is the case of African violet (Saintpaulia ionantha Wendl.), where a generalized temperature response for leaf growth and development has not been developed yet. The objective of this study was to develop a generalized nonlinear temperature response function for leaf appearance rate and leaf elongation rate in African violet. The nonlinear function has three coefficients, which are the cardinal temperatures (minimum, optimum, and maximum temperatures). These coefficients were defined as 10, 24, and 33ºC, based on the cardinal temperatures of other tropical species. Data of temperature response of leaf appearance rate and leaf elongation rate in African violet, cultivar Utah, at different light levels, which are from published research, were used as independent data for evaluating the performance of the nonlinear temperature response function. The results showed that a generalized nonlinear response function can be used to describe the temperature response of leaf growth and development in African violet. These results imply that a reduction in the number of input data required in African violet simulation models is possible.

Copyright of Agricultural Research in the Tropics / Pesquisa Agropecuária Tropical is the property of Pesquisa Agropecuaria Tropical and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The characterization of the developmental phases of agricultural crops is important for management practices and for gladiolus in the field this characterization has not been made in Rio Grande do Sul State. The goal of this study was to determine the duration of vegetative and reproductive phases of the developmental cycle, and the relationships between them and with leaf appearance in gladiolus cultivars. Two field experiments were conducted in Santa Maria, RS, Brazil, one during the Spring/Summer 2010/11 with the cultivars 'Priscila', 'Peter Pears', 'Sunset', 'T704', 'Traderhorn', 'Rose Supreme' and 'Jester', and another during the Fall/Winter 2011 with the cultivars 'T704', 'Traderhorn' and 'Jester'. The experimental design was a completely randomized with two replications of five plants per cultivar. The date of heading and end of flowering was determined and the developmental cycle was divided into vegetative (from planting to heading) and reproductive (from planting to and of flowering). Results showed that the duration of the vegetative phase determines the duration of the developmental cycle and the duration of the vegetative phase is affected by leaf appearance rate and by final leaf number. Thus, early cultivars have greater leaf appearance rate and lower final leaf number than late cultivars. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of increasing doses of potassium silicate on the leaf growth of sugarcane under controlled conditions. The experiment was conducted in a completely randomized design, with six replications and six treatments consisting of doses of potassium silicate (0, 40, 80, 160, 200 and 240 g L-1). The leaf application of potassium silicate quadratically increased the leaf growth of sugarcane. The maximum growth of the leaf area and dry matter production of leaves were obtained with doses of 66.6 and 40.0 g L-1 of potassium silicate, respectively. With a dose of 51.0 g L-1 of potassium silicate, the maximum estimated value of leaf area ratio was obtained. The content of potassium (K) present in the dry matter of the leaf +1 responded linearly to the doses of potassium silicate. However, the high concentration of K in function of the application of high doses of potassium silicate reduced the leaf growth of sugarcane. Therefore, to obtain the maximum leaf growth of sugarcane the dose of potassium silicate to be applied should be between 40.0 and 66.6 gL-1. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The research about the leaf development is very important to evaluate the plants growth and development. The objective of this research was to verify the different level consequences about the irrigation water manner in the leaf growth and the number of the Kalanchoe leaves. The experimental search used was completely randomized, with eight treatments, they consisted in 15; 13; 11; 9; 8; 6; 4 e 2mm irrigation in ten repetitions. The plants leaf area was calculated by the area of each leaf, multiplied by the coefficient of 1.1134. The results showed that the irrigation length between 6 and 9mm showed a bigger leaf growth and more leaves in each plant; the biggest technical efficiency was found with 6.68 and 8.59mm length, to each leaf area and the leaves number in leaf/plant, respectively. In a water condition deficit the Kalanchoe reduces a lot the leaf transversal growth related to the longitudinal. [ABSTRACT FROM AUTHOR]

The research about the leaf development is very important to evaluate the plants growth and development. The objective of this research was to verify the different level consequences about the irrigation water manner in the leaf growth and the number of the Kalanchoe leaves. The experimental search used was completely randomized, with eight treatments, they consisted in 15; 13; 11; 9; 8; 6, 4 e 2mm irrigation in ten repetitions. The plants leaf area was calculated by the area of each leaf, multiplied by the coefficient of 1.1134. The results showed that the irrigation length between 6 and 9mm showed a bigger leaf growth and more leaves in each plant; the biggest technical efficiency was found with 6.68 and 8.59mm length, to each leaf area and the leaves number in leaf/plant, respectively. In a water condition deficit the Kalanchoe reduces a lot the leaf transversal growth related to the longitudinal. [ABSTRACT FROM AUTHOR]