Genotypic differences for temperature response of leaf appearance rate and leaf elongation rate in field-grown maize

This study aims to evaluate the morphogenetic characteristics of three cultivars of Brachiaria brizantha subjected to nitrogen fertilization. The design was a randomized block in factorial arrangement 4x3; three cultivars of B. brizantha - Marandu, Piatã, Xaraés and four nitrogen levels - 0, 80, 160 and 240 kg/ha, with three replications. The experimental units consisted of plastic pots filled with 5 dm3 of soil. Thereupon the establishment fertilization, varieties were sowed directly in the pots, leaving, after thinning, five plants per pot. Forty-five days after planting, it was done a standardization cut at 10 cm tall. Nitrogen levels were distributed according to the treatments, divided in three applications. The morphogenetic characteristics were evaluated in three tillers per sampling unit and data were submitted to analysis of variance and regression. For all evaluated characteristics there was no interaction between factors cultivar and nitrogen levels, verifying only the effects of nitrogen on the variables leaf appearance rate and phyllochron. The dose 240 kg/ha of N corresponds to the greater leaf appearance rate. Cultivar Marandu shows the higher leaf blade: pseudostem and ratio of leaf elongation rate and elongation pseudostem, which favors higher forage quality.

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The growth dynamics in Brachiaria species according to nitrogen dose and shade

Revista Brasileira de Zootecnia ◽

10.1590/s1516-35982011000200006 ◽

2011 ◽

Vol 40 (2) ◽

pp. 270-276 ◽

Cited By ~ 16

Author(s):

Domingos Sávio Campos Paciullo ◽

Priscila Beligoli Fernandes ◽

Carlos Augusto de Miranda Gomide ◽

Carlos Renato Tavares de Castro ◽

Fausto de Souza Sobrinho ◽

...

Keyword(s):

Leaf Blade ◽

Stem Elongation ◽

Growth Dynamics ◽

Elongation Rate ◽

Leaf Elongation ◽

Light Reduction ◽

Appearance Rate ◽

Leaf Elongation Rate ◽

Leaf Appearance Rate ◽

Leaf Appearance

It was studied the effects of shading (0, 36 and 54%) and of four nitrogen doses (0, 50, 100 and 150 mg N/dm³ of soil) on the morphogenetic traits and on the tillering of grasses of Brachiaria genus (B. decumbens, B. ruziziensis and B. brizantha cv. Marandu and cv. Xaraes), cultivated in pots with 5 kg substrate. It was used a complete random design, in a 3 × 4 × 4 factorial scheme with three replications. Nitrogen promoted increase in leaf appearance rate and in average leaf blade length, whereas shading increased stem elongation rate. Leaf elongation rate and tillering varied with the interaction among shading percentages and nitrogen doses. Shading increased response efficiency of leaf elongation rate to nitrogen doses, but reduced for tillering, evidencing priority existing tillering growth in detriment to appearance of new tillers when there is light restriction for the plants. Phenotypic adjustments, in response to light reduction, indicate that the studied grasses present tolerance to moderate shading.

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

Semina Ciências Agrárias ◽

10.5433/1679-0359.2016v37n4p2099 ◽

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.

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

Revista Engenharia na Agricultura - REVENG ◽

10.13083/reveng.v28i.932 ◽

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.

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Temperature response function for leaf appearance rate in wheat and corn

Canadian Journal of Plant Science ◽

10.4141/p97-148 ◽

1999 ◽

Vol 79 (1) ◽

pp. 1-10 ◽

Cited By ~ 19

Author(s):

Y. W. Jame ◽

H. W. Cutforth ◽

J. T. Ritchie

Keyword(s):

Response Function ◽

Plant Development ◽

Full Range ◽

Beta Function ◽

Temperature Response ◽

Base Temperature ◽

Appearance Rate ◽

Leaf Appearance Rate ◽

Leaf Appearance ◽

Rate Of Leaf Appearance

The ability to predict leaf appearance would enhance our capability of modeling plant development and the rate of leaf area expansion. Many crop models use the constant thermal time for successive leaf tip appearance (which is often termed a phyllochron) as one model parameter to predict total number of leaves and date of anthesis. However, many researchers have found that phyllochron is not constant, but is dependent upon environment. The problem could be related to the simplified assumption that the daily leaf appearance rate is linearly related to temperature (and hence, phyllochron is constant, independent of temperature). In reality, the temperature response function for the development of a biological system is nonlinear. Thus, we fitted daily leaf appearance rate–temperature relationships obtained from growth room studies for both wheat (Triticum aestivum) and corn (Zea mays L.) to a nonlinear beta function with 0 °C as the base temperature and 42 °C as the upper critical temperature. The function described the relationships very well over the full range of temperatures for plant development. Other variables that are used to describe the duration and rate of leaf appearance, such as calendar days, phyllochron, and thermal rate of leaf appearance, are related to the daily leaf appearance rate, eliminating the need to develop various mathematical functions to independently describe the response of these variables to temperature. Because of the nonlinear nature of the temperature response function, we demonstrated that more accurate determinations of daily leaf appearance rates can be achieved by calculating rates over relatively short periods (i.e., hourly) and summing these to get the mean daily rate. Many environmental factors other than temperature also affect leaf appearance rate. However, once the proper temperature response function for leaf appearance rate is determined, it is much easier to determine when and how other factors are involved to modify the leaf appearance rate under a given environment.Key words: Temperature, leaf appearance rate, phyllochron, wheat, corn, beta function

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Morphogenic and structural characteristics of Panicum cultivars during the establishment period in the Brazilian Northeast

Acta Scientiarum Animal Sciences ◽

10.4025/actascianimsci.v43i1.50984 ◽

2020 ◽

Vol 43 ◽

pp. e50984

Author(s):

Ana Beatriz Graciano da Costa ◽

Gelson dos Santos Difante ◽

Antonio Leandro Chaves Gurgel ◽

Emmanuel Lievio de Lima Veras ◽

Jéssica Gomes Rodrigues ◽

...

Keyword(s):

Population Density ◽

Leaf Blade ◽

Structural Characteristics ◽

Stem Elongation ◽

Elongation Rate ◽

Panicum Maximum ◽

Appearance Rate ◽

Leaf Appearance Rate ◽

Leaf Appearance ◽

Brazilian Northeast

This study aimed to evaluate the morphogenic and structural characteristics of six Panicum maximum cultivars during the establishment period. A completely randomized block design with four replicates and six treatments (Tamani, Mombaça, Massai, Tanzania, Aruana and Zuri cultivars) was used. Morphogenic (leaf appearance rate, leaf elongation rate e stem elongation rate), structural (final leaf length, tiller population density e number of leaves per tiller) and productive (forage mass, leaf blade mass, stem mass, senescent material mass and leaf:stem ratio) characteristics were evaluated. There was no difference (p > 0.05) between the cultivars in terms of the number of live leaves per tiller (2.95 leaves/tiller). Mombaça cultivar had (p < 0.05) higher canopy height (50.64 cm) compared with other cultivars. The highest (p < 0.05) tiller population density was observed in Tamani (235.90 tillers m-2) and Massai (201.60 tillers m-2) cultivars. Leaf lifespan (54.18 days), phyllochron (17.40 days/leaf) and leaf senescence rate (0.87 cm tiller day-1) were not different (p > 0.05) between cultivars. However, leaf appearance rate was higher (p < 0.05) in Tanzania (0.07 leaves tiller day-1) than in Aruana cultivar (0.05 leaves tiller day-1). Leaf blade mass was higher (p < 0.05) in Mombaça cultivar (1518.31 kg DM ha-1), whereas Massai showed higher (p < 0.05) leaf:stem ratio (9.25). Panicum cultivars Tamani, Tanzania and Massai establishment after 75 days, while the other cultivars establish at 105 days of sowing in the Brazilian Northeast.

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Morphology and Rubisco turnover characteristics of perennial ryegrass breeding populations after two and four cycles of divergent selection for long or short leaf length

Crop and Pasture Science ◽

10.1071/cp13066 ◽

2013 ◽

Vol 64 (7) ◽

pp. 687 ◽

Cited By ~ 3

Author(s):

Edith N. Khaembah ◽

François Gastal ◽

Serge Carre ◽

Louis J. Irving ◽

Philippe Barre ◽

...

Keyword(s):

Perennial Ryegrass ◽

Morphological Traits ◽

Dry Matter ◽

Leaf Length ◽

Elongation Rate ◽

Leaf Elongation ◽

Plant Yield ◽

Leaf Elongation Rate ◽

Selection For ◽

Leaf Appearance

Perennial ryegrass populations previously subjected to two or four cycles of selection for short or long leaf length were studied to determine the response of morphological traits to selection and interaction to determine yield. Measured morphological traits were leaf length, leaf appearance interval, ligule appearance interval, leaf elongation duration, leaf elongation rate, tiller number, tiller dry weight, and herbage dry matter. Additionally, Rubisco concentration during leaf development was measured to determine the association of Rubisco turnover with morphological characteristics and yield. Rubisco was measured and modelled as a three-parameter (D, peak Rubisco concentration; G, time of D; and F, curve width measure), log-normal curve. Leaf length, leaf elongation rate, tiller weight, and plant dry matter diverged after two cycles of selection and further divergence occurred, with these traits being, respectively, 35, 28, 53, and 61% greater in the long- than the short-leaved plants after four cycles of selection. Opposite trends were displayed by Rubisco turnover, with selection for long leaves co-selecting for increased Rubisco turnover time and selection for short leaves resulting in increased leaf Rubisco concentration. There was indication of coupling of leaf appearance with Rubisco turnover. Across populations, multivariate analysis indicated that plant yield was associated with Rubisco concentration rather than Rubisco turnover. The association between higher yield and lower Rubisco concentration could be targeted in the breeding of high-yielding, nitrogen-efficient forage grasses. Plant yield was mainly associated with increased leaf area, indicating that yield could be improved by selecting for longer leaves and faster rates of leaf expansion.

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Morphogenesis of stockpiled Marandu, Piatã, Xaraés and Paiaguás brachiariagrass cultivars

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/1678-4162-12332 ◽

2021 ◽

Vol 73 (6) ◽

pp. 1413-1421

Author(s):

M.E.R. Santos ◽

I.C. Ferreira ◽

B.H.R. Carvalho ◽

G.O. Rocha ◽

G.S. Borges ◽

...

Keyword(s):

Leaf Growth ◽

Stem Elongation ◽

Elongation Rate ◽

Pasture Management ◽

Randomized Design ◽

Appearance Rate ◽

Leaf Appearance Rate ◽

Completely Randomized Design ◽

Urochloa Brizantha ◽

Leaf Appearance

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.

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A temperature response function for modeling leaf growth and development of the African violet (Saintpaulia ionantha Wendl.)

Ciência Rural ◽

10.1590/s0103-84782004000100009 ◽

2004 ◽

Vol 34 (1) ◽

pp. 55-62 ◽

Cited By ~ 9

Author(s):

Nereu Augusto Streck

Keyword(s):

Response Function ◽

Growth And Development ◽

Leaf Growth ◽

Temperature Response ◽

Simulation Models ◽

African Violet ◽

Appearance Rate ◽

Leaf Appearance Rate ◽

Leaf Appearance ◽

Cardinal Temperatures

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.

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The Tissue Flow in Brachiaria brizantha Pasture Under Intermittent Stocking

Journal of Agricultural Studies ◽

10.5296/jas.v8i1.15441 ◽

2020 ◽

Vol 8 (1) ◽

pp. 9

Author(s):

Caio Vinicio Vargas de Oliveira ◽

Rodrigo Amorim Barbosa ◽

Raísa Turcato de Oliveira ◽

Emizael Menezes de Almeida ◽

Francielly Paludo ◽

...

Keyword(s):

Phenotypic Plasticity ◽

Structural Characteristics ◽

Abiotic Factors ◽

Structural Variations ◽

Brachiaria Brizantha ◽

Area Index ◽

Appearance Rate ◽

Leaf Elongation Rate ◽

Leaf Appearance Rate ◽

Leaf Appearance

The present work aims to evaluate the morphological and structural characteristics of Brachiaria brizantha cultivars in the system of grazing in the intermittent stocking. The experiment was conducted at EMBRAPA - Beef Cattle. The experimental delineation used was a randomized block with three treatments and three repetitions. The treatments were constituted by grasses of the same species (Brachiaria brizantha) composed by cv. Xaraés, BRS Paiaguás, and the ecotype B4. On the heights of post-grazing, it was observed an interaction between seasons of the year and cultivars. It was observed that the leaf appearance rate (LAR) was higher in the cv. BRS Paiaguás, in relation to the other pastures. The leaf elongation rate (LER) was higher in perforations of the ecotype B4. In the winter, it was registered the lowest values of leaf area index (LAI), LAR, and LER, and, as a consequence, impact in a higher leaf life duration. Although there were some structural variations between tropical climate pastures, it was possible to verify that the phenotypic plasticity of these pastures presented the same behavior, once it suffered a higher influence of abiotic factors. Therefore, all the pastures of B. brizantha converged to the same LAI indicating high phenotypic plasticity.

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