Adams RH, AL Álvarez-Ovando, G Castañón N

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 222-232, 2015, DOI:10.32604/phyton.2015.84.222

Abstract In this study, the relationship between the concentration of extra-heavy crude petroleum in a clayey material and the toxicity, field capacity, temperature, and growth of a tropical forage grass (Brachiara humidicola) was determined empirically. For this type of petroleum the acute toxicity (Microtox^®) was slight (CE₅₀ = 63200 - 76400 mg/kg) even at high hydrocarbon concentrations (29279 mg/kg). Nonetheless, serious impacts were encountered in terms of an increase in soil temperature (+ 1.3 °C), reduction in field capacity (-10.7%) and reduction in aerial biomass (-97%). The relationship between hydrocarbon concentration and biomass resulted in a typical dose-response curve (r =… More >

Hu FL^1,2, B Liu^1,3, ZM Liu^1,3, YT Fang^1,3, CA Busso⁴

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 209-221, 2015, DOI:10.32604/phyton.2015.84.209

Abstract Grasslands are one of the most widespread landscapes worldwide, covering approximately one-fifth of the world’s land surface, where grazing is a common practice. How carbon storage responds to grazing in steppes remains poorly understood. We quantified the effects of grazing on community composition and species diversity, and carbon storage in two typical grasslands of northeastern China, one in Horqin and the other one in Hulunbeier. In both grasslands, grazing did not influence plant species diversity. However, it substantially decreased aboveground carbon by 31% and 54% in Horqin and Hulunbeier, respectively. Fenced and grazing treatments showed a similar belowground carbon at… More >

Montes B^1,2, MG Murray^1,3

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 201-208, 2015, DOI:10.32604/phyton.2015.84.201

Abstract Palynological studies contribute to understanding the taxonomy, phylogeny and ecology of the Asteraceae and other families. In this study, pollen morphology and ultrastructure of the exine of Senecio bergii Hieron. were studied using light, scanning and transmission electron microscopy. The pollen of this species is prolate-spheroidal, it has a Senecioid pattern on the exine and an apertural system composed of three apertures (ecto-, meso- and endoapertures). This pollen type is defined as tricolpororate due to the triple apertural system. This is the first description of the ultrastructure of the apertural system of the pollen of Argentine species of Senecio. The… More >

Morales-Nieto CR¹, C Avendaño-Arrazate², A Melgoza-Castillo¹, M Martinez-Salvador³, P Jurado-Guerra⁴

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 190-200, 2015, DOI:10.32604/phyton.2015.84.190

Abstract Plains bristlegrass (Setaria macrostachya Kunth) is a native grass with forage value. However, due to the lack of grazing management practices, populations and thus genetic diversity, have been reduced. Morphological and genetic variability were analyzed on 44 populations of plains bristlegrass in the State of Chihuahua. Plants were transplanted in a common area under natural conditions. Two years later, morphological characterization was evaluated measuring nine variables, and genetic variability using AFLP molecular markers. The principal components analysis (PC) showed that the three first principal components explained 73.74% of the variation. The variables with the greatest contribution to the variance in… More >

Perissé P¹ y GM Tourn²

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 184-189, 2015, DOI:10.32604/phyton.2015.84.184

Abstract The morphological characteristics of the seeds of Vicia dasycarpa Ten. cv. Tolse FCA were studied in relation to the area of imbibition water entry and were considered the presence of areoles. Seeds were analyzed using a stereo, optical and scanning electron microscope (SEM). The determination of the initial water entry area was carried out by immersing the seeds in a solution of tetrazolium (1%). This study showed that this species has seeds with a halo framing the hilum, an inconspicuous dry aril and a deltoid micropyle. The seedcoat pattern is papillose. The tracheid bar is surrounded by a ring of… More >

Moya ME^1,2, AA Galussi^1,2, MJ Gómez^1,2, FG Marchese^1,2

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 176-183, 2015, DOI:10.32604/phyton.2015.84.176

Abstract The aim of the present work was to analyze the foliar anatomy in lamina transverse section an in epidermis superficial view of Mnesithea selloana. Epidermic preparations and transections were carried out of the medium leaf part of sterile innovations that were conditioned and observed with optic microscope (OM) and scanning electron microscope (SEM).The histofoliar characteristics observed were: epidermic, intercostal, subsidiary, suberose, silicea and bulliform cells; and also guard cells, hairs, waxes, mesophylls, Kranz sheath, vascular bundles, sclerenchyma, colourless parenchyma and leaf margin. Epidermic observations showed that M. selloana presents a panicoid type epidermis presenting silicic cells as halteriforme, longer than… More >

Galussi AA¹, JA Argüello², MM Cerana², M Maximino³, ME Moya¹

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 163-175, 2015, DOI:10.32604/phyton.2015.84.163

Abstract Seeds of alfalfa (Medicago sativa L.) can exhibit seedcoat imposed dormancy, which produces hard seeds within a seed lot. These seeds do not germinate because they do not imbibe water due to a barrier to water entry in the seed coat. The aim of this work was to analyze the anatomical and chemical characteristics of the testa of alfalfa seeds with respect to water permeability levels. The anatomy of seeds of the cv. Baralfa 85 was studied and structural substances, polyphenols, tannins and cutin present in the testa of seeds of different water permeability levels were determined. The anatomical characteristics… More >

Avendaño-Arrazate CH¹, L Iracheta-Donjuan¹, JC Gódinez-Aguilar², P López-Gómez¹, A Barrios-Ayala³

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 148-162, 2015, DOI:10.32604/phyton.2015.84.148

Abstract The agave papalote (Agave cupreata Trelease) which is endemic to the Guerrero state, Mexico, is propagated exclusively by seed, but it is overutilized and knowledge of its diversity is needed for its protection. Therefore, the study aimed to determine the morphological variation in wild and cultivated populations of Agave cupreata in five areas of Guerrero. Ninety one characters were evaluated in situ, and only 51 qualitative and quantitative morphological characters of the plant, leaf spine, flower, fruit, seed and flower stalk were selected. The work was carried out in five different altitudinal zones, according to the level of production of… More >

Turkyilmaz Unal B¹, A Esiz Dereboylu²

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 144-147, 2015, DOI:10.32604/phyton.2015.84.144

Abstract The aim of the study was to investigate some physiological effects of an insecticide (Akira 20-SP) with acetamiprid agent on Cin misir Adapop 10 and Sert misir Adapop 2 cultivars of corn plants in different concentrations [0 g/L, 0.6 g/L (recommended concentration), 1.2 g/L]. Photosynthetic pigment substances, total soluble protein and proline contents were determined. Analysis of treated leaves showed that the recommended concentration resulted in higher chlorophyll value in Cin misir Adapop 10 and Sert misir Adapop 2. Carotenoid amounts increased in Cin misir Adapop 10 and decreased in Sert misir Adapop 2 to the control. Total protein contents… More >

Lazos-Monterrosa FA, C Orantes-García, O Farrera-Sarmiento, AG Verdugo-Valdez, MS Sánchez-Cortés, LE Ruíz-Meza

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 138-143, 2015, DOI:10.32604/phyton.2015.84.138

Abstract The tempisque (Sideroxylon capiri) is a tree native to Mexico used by the rural population for housing construction, poles and hedges, as fuel (wood) and also for fodder and ornamental purposes, among others. It is considered an endangered species. In order to contribute to its preservation and sustainable management, it was considered important to determine the proportion of viable seeds, the loss of viability due to storage period and the germination process by applying pregerminative treatments. We found that freshly collected seeds showed 100% viability, which decreased to 0% after 5 months of storage. According to the cumulative germination significant… More >