scholarly journals Morphogenetic and structural characteristics of xaraes palisadegrass submitted to cutting heights

2011 ◽  
Vol 40 (1) ◽  
pp. 53-59 ◽  
Author(s):  
Braulio Maia de Lana Sousa ◽  
Domicio do Nascimento Júnior ◽  
Carlindo Santos Rodrigues ◽  
Hélida Christhine de Freitas Monteiro ◽  
Sila Carneiro da Silva ◽  
...  
Keyword(s):  
Structural Characteristics ◽  
Stem Elongation ◽  
Block Design ◽  
Growth Conditions ◽  
Light Interception ◽  
Elongation Rate ◽  
Cutting Condition ◽  
Leaf Elongation ◽  
Randomized Block Design ◽  
Leaf Elongation Rate

The objective of this work was to evaluate the morphogenetic and structural characteristics of xaraes palisadegrass submitted to three cutting heights (15, 20 and 25 cm) when the sward reached 95% of light interception during regrowth. The experiment was carried out according to a complete randomized block design with three replications. The sward surface height under the cutting condition of 95% of light interception was very homogeneous with values around 30 cm. The increase in cutting height reduced the leaf elongation rate and the number of live leaves but increased stem elongation rate. As the cutting criterion was the same, before the intense competition for light, the variation in the cutting severity had a small influence on the morphogenetic and structural characteristics of this grass. In the summer, due to the better growth conditions, the plants presented a higher tissue renewal, which was characterized by a higher leaf elongation rate, reduced leaf lifespan and leaf senescence rate when compared to the other season of the year. Under intermittent defoliation conditions, the regrowth of xaraes palisadegrass can be interrupted at a sward height of 30 cm (frequency) keeping a residual height of 15 cm.

scholarly journals Morphogenesis and structure of mombassa grass over different growth periods

2017 ◽  
Vol 38 (5) ◽  
pp. 3271
Author(s):  
Márcio Odilon Dias Rodrigues ◽  
Antonio Clementino dos Santos ◽  
Marcos Odilon Dias Rodrigues ◽  
Rubens Ribeiro da Silva ◽  
Otacilio Silveira Junior
Keyword(s):  
Structural Characteristics ◽  
Stem Elongation ◽  
Pearson Correlation ◽  
Block Design ◽  
Elongation Rate ◽  
N Fertilizer ◽  
Panicum Maximum ◽  
Forage Production ◽  
Leaf Elongation ◽  
Leaf Appearance

This study aimed to evaluate the effect of nitrogen (N) fertilizer doses on morphogenic and structural characteristics of mombassa grass (Panicum maximum Jacq.) at three different periods of the lifespan of tillers. The experiment was conducted in Araguaína-TO, Brazil, from December 2014 to February 2015. It was installed in split plots in a randomized block design with four replications. The doses of N-fertilizer (0, 30, 60, 90 kg N.ha-1) were the plots and the periods evaluated (1PER – first period from day 16 to 30; 2PER from day 31 to 45 and 3PER from day 46 to 60 after germination) were the subplots. The evaluated variables consisted of leaf appearance rate (LAR), leaf elongation rate (LER), stem elongation rate (SER), leaf senescence rate (LSR), phyllochron, tiller number, leaf emergence, and total leaf number. A Pearson correlation analysis was used to morphogenic and structural characteristics along with a regression analysis for all the variables. Overall, increasing N-fertilizer doses positively influenced the leaf appearance and leaf elongation rates, tiller density, and the number of live leaves per tiller. The 90-kg N.ha-1 dose enabled the best morphogenic and structural responses of the forage when compared to the other rates. Each period featured differently, with higher values of LSR, SER, and LER in 3PER when compared to those in 2PER and in 1PER. Therefore, the nutritional supply over the first weeks of tiller lives was defining to an increase in forage production in the remaining periods. In light of this, we observed that as LAR raise in the first days after germination, nutritional supplies are required from day 15 on, mainly nitrogen, so plants could continue their development since initial plant growth determines pasture productive vigor and longevity.

scholarly journals Morphogenic and structural characteristics of guinea grass pastures submitted to three frequencies and two defoliation severities

2011 ◽  
Vol 40 (5) ◽  
pp. 947-954 ◽  
Author(s):  
Rodrigo Amorim Barbosa ◽  
Domicio do Nascimento Júnior ◽  
Hélio Henrique Vilela ◽  
Sila Carneiro da Silva ◽  
Valéria Pacheco Batista Euclides ◽  
...  
Keyword(s):  
Structural Characteristics ◽  
Stem Elongation ◽  
Incident Light ◽  
Light Interception ◽  
Experimental Unit ◽  
Leaf Elongation ◽  
Randomized Design ◽  
Leaf Elongation Rate ◽  
Guinea Grass ◽  
Defoliation Frequency

It was evaluated the morphogenic and structural characteristics of guinea grass under rotational at three grazing intervals and two defoliation intensities. Grazing intervals corresponded to the time needed by the forage canopy to reach 90, 95 or 100% of incident light interception during regrowth and they were evaluated combined to two defoliation severities (post-grazing conditions, 25 and 50 cm of height), being allocated to experimental units according to a complete randomized design, with three replicates and 3 × 2 factorial arrangement. The experiment was conducted from July 2003 to May 2004. For evaluation of morphogenetic and structural characteristics, ten tillers per experimental unit were selected. Morphogenetic and structural characteristics were strongly influenced by seasons of the year inasmuch as leaf elongation rate increased 3.5 fold from winter to summer. In addition to year season effect, there was also an effect of defoliation frequencies on tiller population density, which was greater in the defoliation period corresponding to 90% of light interception, especially if evaluated in relation to the interval corresponding to 100% of light interception. Defoliation frequency is determinant in expression of phenotypic plasticit, acting on the control of stem elongation.

scholarly journals Morphogenetic and structural characteristics of andropogon grass submitted to different cutting heights

2010 ◽  
Vol 39 (10) ◽  
pp. 2141-2147 ◽  
Author(s):  
Braulio Maia de Lana Sousa ◽  
Domicio do Nascimento Júnior ◽  
Sila Carneiro da Silva ◽  
Hélida Christhine de Freitas Monteiro ◽  
Carlindo Santos Rodrigues ◽  
...  
Keyword(s):  
Leaf Blade ◽  
Structural Characteristics ◽  
Stem Elongation ◽  
Block Design ◽  
Growth Conditions ◽  
Leaf Lifespan ◽  
Blade Length ◽  
Sward Height ◽  
Randomized Block Design ◽  
Andropogon Gayanus

This work was performed aiming to evaluate the morphogenetic and structural characteristics of Andropogon gayanus cv. Planaltina species submitted to three cutting heights (20, 27 and 34 cm). The three cutting heights were allocated in experimental units (12 m²) in a complete randomized block design with three replications. The cuts were done when the light interception by the sward reached 95%. At this moment, the sward height revealed itself constant with values close to 50 cm. The lowest cutting height (20 cm) influenced negatively the final leaf blade length, the number of live leaves, the leaf lifespan, the stem elongation rate and the tiller population density, and it influenced positively the phyllochron and the leaf senescence rate. Probably, cuts at 20 cm height caused a high decapitation and death of the tillers. The worst growth conditions in addition to the blossom of this specie occurred during fall resulted in higher stem elongation rates and number of live leaves, and lower phyllochron, final leaf blade length, and leaf lifespan. The sward height can be used as a practical and efficient criterion in the management of andropogon grass. Under intermittent management conditions, the regrowth of andropogon grass must be interrupted when the sward reaches 50 cm height, and the defoliation must be interrupted when the stubble height is close to 27 cm.

scholarly journals Morphogenetic and structural characteristics of signal grass in response to liming and defoliation severity

2018 ◽  
Vol 48 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Lilian Elgalise Techio Pereira ◽  
Valdo Rodrigues Herling ◽  
Junior Cesar Avanzi ◽  
Sila Carneiro da Silva
Keyword(s):  
Soil Acidity ◽  
Structural Characteristics ◽  
Stem Elongation ◽  
Block Design ◽  
Late Spring ◽  
Leaf Elongation ◽  
Tolerance Limits ◽  
Randomized Block Design ◽  
Urochloa Decumbens ◽  
Adequate Management

ABSTRACT The control of soil acidity through liming and the adoption of adequate management are essential to the maintenance of pastures productivity. The morphogenetic and structural characteristics of Urochloa decumbens cv. Basilisk, in canopies with (0.7 t ha-1 and 1.0 t ha-1) or without liming and subjected to severe or lenient cuttings (stubble corresponding to 40 % or 60 % of the pre-harvest height, respectively), were evaluated throughout regrowth, during late spring and summer. Treatments were distributed in a 3 x 2 factorial arrangement, in a completely randomized block design, with 3 replications (80 m2 plots). Increased liming rates do not result in benefits to the herbage mass, tiller population density or a faster canopy recovering. The average tiller weight decreases, while the duration of regrowth linearly increases, with increasing liming rates, particularly in late spring. Stem elongation and leaf senescence rates increase and leaf elongation rates decrease from the 15th day of regrowth, regardless of the liming rates or defoliation severities. Post-harvest heights ranging from 40 % to 60 % of the pre-harvest height showed to be within the tolerance limits to defoliation of U. decumbens. The liming rates adopted had only marginal impacts on the morphogenetic characteristics of U. decumbens.

scholarly journals MORFOLOGIA FOLIAR DE SORGO SACARINO CULTIVADO EM DIFERENTES ESPAÇAMENTOS ENTRELINHAS E ÉPOCAS DE SEMEADURA

2018 ◽  
Vol 17 (1) ◽  
pp. 63
Author(s):  
ANDRIELI HEDLUND BANDEIRA ◽  
SANDRO LUIS PETTER MEDEIROS ◽  
BEATRIZ MARTI EMYGDIO ◽  
JEAN CECCHIM BIONDO ◽  
LINEU TRINDADE LEAL
Keyword(s):  
Sorghum Bicolor ◽  
Sweet Sorghum ◽  
Block Design ◽  
Shoot Elongation ◽  
Elongation Rate ◽  
Leaf Elongation ◽  
Sowing Time ◽  
Leaf Elongation Rate ◽  
Line Spacing ◽  
Sorghum Genotypes

RESUMO - O objetivo deste trabalho foi avaliar as características morfogênicas do colmo principal de genótipos de sorgo sacarino, em diferentes espaçamentos entrelinhas e épocas de semeadura. O experimento foi conduzido em Santa Maria-RS, em delineamento experimental de blocos ao acaso em esquema trifatorial (2x2x3), com dois genótipos de sorgo sacarino (BRS 506 e Fepagro 19), dois espaçamentos entrelinhas (0,50 m e 0,70 m) e três épocas de semeadura (outubro, novembro e dezembro), quatro repetições e dois anos de cultivo. Foram avaliadas a taxa de alongamento das folhas, o número final de folhas no colmo, a taxa de surgimento de folha, filocrono e taxa de elongamento de colmo. As variáveis não apresentaram interação tripla significativa entre genótipo, espaçamento de entrelinhas e época de semeadura. O genótipo BRS 506 apresentou número de folhas acumuladas, taxa de alongamento de folhas nas épocas de semeaduras constante. O atraso na época de semeadura resulta em menor número de folhas acumuladas e taxa de elongação do colmo para o Fepagro 19. O filocrono para o espaçamento entrelinhas 0,70 m é inferior ao de 0,50 m. Os genótipos estudados estão aptos para a produção na região, desde que a semeadura ocorra no mês de outubro. Palavras-chave: alongamento foliar, filocrono, graus-dia, índice Haun, Sorghum bicolor. LEAF MORPHOLOGY OF SWEET SORGHUM CULTIVATED IN DIFFERENT ROW SPACINGS AND SOWING DATES ABSTRACT - The objective of this work was to evaluate the morphogenic characteristics of the main stem of sweet sorghum genotypes in different spacing between lines and sowing times. The experimental was carried out in a randomized complete block design in a trifactorial scheme (2x2x3), with two sweet sorghum (BRS 506 and Fepagro 19), two spacing between lines (0.50 m and 0.70 m) and three sowing seasons (October, November and December), four replications and two years of cultivation. The leaf elongation rate, the final number of leaves in the stem, the leaf appearance rate, phyllochron and shoot elongation rate were evaluated. The variables did not present significant triple interaction between genotype, spacing between rows and sowing time. The genotype BRS 506 presented a number of accumulated leaves, leaf elongation rate at constant sowing times. The delay in sowing seasons results in a lower number of accumulated leaves and the elongation rate of the stem for genotype Fepagro 19. The phyllochron for the 0.70 m line spacing is less than 0.50 m. The genotypes studied are suitable for production in the region, as long as sowing occurs in October.Keywords: leaf elongation, phyllochron, degree-days, Haun index, Sorghum bicolor.

scholarly journals Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures

2016 ◽  
Vol 37 (4) ◽  
pp. 2043
Author(s):  
Wilton Ladeira Silva ◽  
Ana Cláudia Ruggieri ◽  
Ricardo Andrade Reis ◽  
Américo Garcia Silva Sobrinho ◽  
Euclides Braga Malheiros
Keyword(s):  
Structural Characteristics ◽  
Stem Elongation ◽  
Light Interception ◽  
Climatic Conditions ◽  
Leaf Length ◽  
Elongation Rate ◽  
Area Index ◽  
Structural Variables ◽  
Senescence Rate ◽  
Leaf Appearance

The ideal time to start grazing is when pastures reach 95% light interception. The use of residual leaf area index (rLAI) to time the interruption of grazing under intermittent grazing has recently been studied in forage species in different climatic conditions in Brazil. However, studies evaluating the formation and development of leaves and tillers through morphogenetic and structural variables in functional rLAI are still lacking for Tifton 85 pastures. Therefore, the objective of this study was to evaluate the effects of varying rLAI in successive grazing cycles on morphogenetic and structural characteristics of Tifton 85 pasture grazed intermittently by sheep. Morphogenetic and structural characteristics were evaluated in three grazing cycles under three rLAI conditions (0.8, 1.6, and 2.4). The regrowth interval (time taken to return to 95% light interception) of pastures increased from 21.33 to 29.66 days with decreasing rLAI. The leaf appearance rate increased at a rate of 0.02 leaves tiller-1 day-1 and the number of live leaves per tiller increased by 0.41 with decreasing rLAI. Phyllochron, leaf elongation rate, final leaf length, leaf senescence rate, and stem elongation rate decreased linearly with decreasing rLAI. The number of live leaves per tiller was lower (7.97) in the third grazing cycle, probably owing to the higher senescence rate observed that same cycle, while the other variables had higher values. The 2.4 rLAI condition promotes excessive stem elongation, reduced leaf appearance, lower number of live leaves per tiller, and increased senescence of leaves, while the 0.8 and 1.6 rLAI conditions promote desirable morphogenetic and structural characteristics, which correlate directly with forage quality. In order to avoid excessive forage losses, grazing must occur preferentially by the end of March, when climatic conditions still support the appropriate development of the plants.

scholarly journals Morphogenetic, structural and production traits of marandu grass under nitrogen rates in Neo soil

2021 ◽  
Vol 73 (3) ◽  
pp. 658-664
Author(s):  
A.B.G. Costa ◽  
G.S. Difante ◽  
B.A.M. Campelo ◽  
A.L.C. Gurgel ◽  
C.M. Costa ◽  
...  
Keyword(s):  
Stem Elongation ◽  
Block Design ◽  
N Fertilization ◽  
Leaf Length ◽  
Elongation Rate ◽  
Natural Fertility ◽  
Production Traits ◽  
Brachiaria Brizantha ◽  
Randomized Block Design ◽  
Leaf Appearance Rate

ABSTRACT Most sandy soils have low natural fertility and low levels of organic matter, making nitrogen (N) fertilization essential. Thus, five doses of N were applied (0, 75, 125, 175 and 225mg dm-³) in a randomized block design to evaluate the effects of nitrogen fertilization on the morphogenetic, structural and production characteristics of Brachiaria brizantha cv. Marandu in a Quartzarenic neosoil. The doses of N did not affect the height of the canopy. The leaf elongation rate, final leaf length and number of live leaves increased linearly at the doses of N. Leaf appearance rate, stem elongation rate, leaf lifespan, phyllochron, leaf senescence rate and tiller density showed a quadratic response to the rates There was also an effect of N rates in herbage mass, leaf mass, stem mass, which increased linearly. Brachiaria brizantha cv. Marandu cultivated in Quartzarenic neosoil requires higher doses of N, 175 and 225mg dm-³. Under these conditions, increases in its morphogenetic, structural and productive characteristics are observed. These findings may not be repeated in the most fertile soils with the greatest capacity to supply N.

scholarly journals Morphogenetic and structural characteristics of clones of elephant grass managed under intermittent stocking

2016 ◽  
Vol 37 (4) ◽  
pp. 2099
Author(s):  
Priscila Beligoli Fernandes ◽  
Carlos Augusto Brandão de Carvalho ◽  
Domingos Sávio Campos Paciullo ◽  
Carlos Augusto De Miranda Gomide ◽  
Mirton José Frota Morenz ◽  
...  
Keyword(s):  
Structural Characteristics ◽  
Stem Elongation ◽  
Elongation Rate ◽  
Leaf Life Span ◽  
Elephant Grass ◽  
Leaf Elongation ◽  
Appearance Rate ◽  
Randomized Experimental Design ◽  
Leaf Appearance Rate ◽  
Leaf Appearance

This work was carried out to evaluate the morphogenetic and structural characteristics of basal and aerial tillers of two dwarf elephant grass clones (BRS Kurumi and CNPGL 00-1-3) managed under intermittent stocking in six grazing cycles. A completely randomized experimental design with three replications (paddocks) in split-split-plot arrangements was used. The clones were allocated to the plots, tiller classes were assigned to the subplots and grazing cycles to sub subplots. Higher values for basal tillers than aerial tillers were seen for the following characteristics: leaf elongation rate (12.8 and 5.1 cm/tiller/day), leaf appearance rate (0.26 and 0.19 leaves/tiller/day), stem elongation rate (0.38 and 0.16 cm/tiller/day), senescence rate (0.98 and 0.47 cm/tiller/day), total number of leaves (9.3 and 7.1 leaves/ tiller), number of live leaves (7.7 and 5.8 leaves/tiller) and final length of leaf blades (33.5 and 20.0 cm). Phyllochron was lower for basal (4.0 days/leaf) than aerial tillers (5.5 days/leaf). The leaf life span increased with the advance of the grazing cycles, averaging 31.2 days. The tiller density increased with the advance of the grazing cycles showing an average increase of 167% of aerial tillers and 62% of basal tillers for both clones. The morphogenetic and structural characteristics of dwarf clones were influenced jointly by the clones and the availability of the environmental factors of growth during the spring and summer. The high leaf elongation rates, associated with high leaf appearance rate, reveal the potential of high production dry matter of leaves and restoration of leaf area after grazing.

scholarly journals GROWTH AND DEVELOPMENT OF MOMBASSA GRASS GROWN IN FULL SUN AND SHADE UNDER NITROGEN LEVELS

2020 ◽  
Vol 28 ◽  
pp. 11-23
Author(s):  
Tiago Barbalho André ◽  
Leonardo Bernardes Taverny de Oliveira ◽  
Antonio Clementino dos Santos
Keyword(s):  
Average Length ◽  
Stem Elongation ◽  
Elongation Rate ◽  
Panicum Maximum ◽  
Leaf Elongation ◽  
Area Index ◽  
Nitrogen Levels ◽  
Leaf Elongation Rate ◽  
Leaf Appearance Rate ◽  
Sun And Shade

The objective of this work was to evaluate the effects promoted by full sun and natural shading (25%) enviroemnts , under the productive components of Panicum maximum cv. Mombasa grown in diferent levels of nitrogen (0, 25, 50, 100 kg ha-1 cycle-1 ). Urea was used as nitrogen source, applied on the surface. This study evaluated the following variables: number of total leaves (NTL), number of green leaves (NGL), number of dead leaves (NDL), leaf lifespan (LLS), sheath length (SL), stem elongation rate (SER), Phyllochron (PHYL), leaf appearance rate (LApR), leaf elongation rate (LElR), leaf senescence rate (LSR), average length of leaf blade (ALLB), leaf area index (LAI) and tiller population density (TPP). The shaded environment provided better conditions for sheath length and leaf elongation rate, however in full sun the tiller density was higher.

scholarly journals Morphogenesis and tiller density of Aruana grass managed at different heights under sheep grazing

2019 ◽  
Vol 40 (5Supl1) ◽  
pp. 2341
Author(s):  
Renata Negri ◽  
Guilherme Batista dos Santos ◽  
Vicente de Paulo Macedo ◽  
Magali Floriano da Silveira ◽  
Leticia Wlodarski ◽  
...  
Keyword(s):  
Stem Elongation ◽  
Block Design ◽  
Leaf Length ◽  
Elongation Rate ◽  
Leaf Life Span ◽  
Sheep Grazing ◽  
Randomized Block Design ◽  
Leaf Appearance Rate ◽  
Representative Area ◽  
Tiller Density

This study aimed to assess the morphogenic characteristics and tiller density of Aruana grass managed at different heights under sheep grazing. Aruana grass was managed at four mean heights (12, 15, 20, and 25 cm) distributed in a randomized block design with three replications, totaling 12 paddocks of 250 m² each. Twenty-four crossbred Dorper x Santa Inês lambs, with mean age and weight of 60 ± 15 days and 16.69 ± 2.70 kg, respectively, were randomly distributed in the treatments. Five tillers were demarcated per paddock for measuring morphogenic variables. A representative area in the paddock was used for counting the number of tillers. No differences (P > 0.05) were observed for leaf appearance rate, leaf elongation rate, stem elongation rate, leaf senescence rate, final leaf length, and leaf life span between the assessed heights. Phyllochron was longer at the height of 25 cm when compared to 15 and 20 cm (19.35, 12.11, and 12.75 days, respectively). The number of live leaves was higher at heights of 12, 15, and 20 cm when compared to 25 cm (3.99, 4.35, 4.15, and 2.86, respectively). The number of basal and aerial tillers presented no variation (P > 0.05) between canopy heights. Management heights from 15 to 20 cm allowed a higher number of live leaves and a shorter phyllochron in Aruana grass pastures managed for sheep. Canopy height management did not influence other morphogenic characteristics and tiller density.

Sign in / Sign up

Export Citation Format

Share Document