Rivera-Reyes¹ JG, FA Peraza-Luna², JC Serratos-Arévalo², P Posos-Ponce³, SH Guzmán-Maldonado⁴, E Cortez-Baheza¹, G Castañón-Nájera⁵, M Mendoza-Elos^1*

Phyton-International Journal of Experimental Botany, Vol.78, pp. 37-42, 2009, DOI:10.32604/phyton.2009.78.037

Abstract Oats cereal is a worldwide significant crop. It is grown in restrictive climates and in rainy regions of temperate areas. Cultivation of oats produces high forage yields and grain quality, which gives it a wide variety of uses as animal feed and human food. However, the physiological quality of oat seeds in Mexico faces problems, which impact both their import and export. Phytic acid concentration in the oat seed plays a very important role since it affects seed viability, its germination capacity and potential seedling vigor. The objective of this study was to determine the effect of chemical fertilization on… More >

Lagoutte¹ S, M Divo de Sesar², F V ilella³

Phyton-International Journal of Experimental Botany, Vol.78, pp. 31-36, 2009, DOI:10.32604/phyton.2009.78.031

Abstract Annual floral plant crops are produced in cells or pots of various sizes. Varying container size alters the volume which plant roots can explore, which in turn affect plant growth. This work assesed the effect of the initial container size on growth of Petunia x híbrida cv Dream Mix, supplemented with cytokinins after potting. Seedlings obtained in trays of 90 or 288 cells, were transplanted to 1l pots. They were then supplemented with 6-bencyladenine (BA). The assay consisted of 4 treatments: two container sizes by two BA conditions (with and without). Cell size conditioned growth above ground and below ground;… More >

Ochoa-Fuentes YM¹, E Cerna², J Landeros², O Vazquez¹, V Olalde³, A Flores²

Phyton-International Journal of Experimental Botany, Vol.78, pp. 25-30, 2009, DOI:10.32604/phyton.2009.78.025

Abstract Forty two Mexican isolates of Phytophthora cinnamomi Rands were examined for genetic diversity by the random amplified polymorphic DNA assay. The amount of genetic variation was evaluated by polymerase chain reaction amplification with a set of twenty one random 10-mer primers. All amplifications revealed scorable polymorphisms among the isolates, and a total of 23 band positions were scored for the 21 primers tested. Genetic distances among the isolates were calculated, and cluster analysis was used to generate a dendogram which showed relationships between them. These results suggest that the geographic groups were strong. More >

Peláez¹ DV, RM Bóo², MD Mayor³, OR Elia⁴, SA Martínez⁵

Phyton-International Journal of Experimental Botany, Vol.78, pp. 17-24, 2009, DOI:10.32604/phyton.2009.78.017

Abstract Plant growth in semiarid rangelands may be affected by time grazing is excluded during the post-fire regeneration period. The objective of this field work was to study the effect of post-fire defoliation at different phenological stages [vegetative (early-season defoliation) and internode elongation (late-season defoliation)] on growth of Piptochaetium napostaense and Poa ligularis, two very important perennial native grasses in the temperate semi-arid region of central Argentina (Caldenal). In general, the post-fire defoliation treatments did not affect the number of green leaves on tillers of P. napostaense. Early-season post-fire defoliation generally reduced the number of green leaves on tillers of… More >

Sánchez E¹, G Ávila-Quezada¹, AA Gardea¹, E Muñoz¹, JM Ruiz², L Romero²

Phyton-International Journal of Experimental Botany, Vol.78, pp. 11-16, 2009, DOI:10.32604/phyton.2009.78.011

Abstract The objective of this work was to determine the effect of different P doses on nitrogen assimilation in roots and leaves of green beans plants (Phaseolus vulgaris L. cv. Strike). Phosphorus was applied in the nutrient solution as H₃PO₄, at the nutrient doses of: P1 = 0.40 mM; P2 = 0.80 mM; P3 = 1.60 mM; P4 = 3.20 mM; P5 = 4.80 mM, and P6 = 6.40 mM P. Our results indicate that both P toxicity and deficiency gave similar responses to N assimilation. Phosphorus and NO3 - interacted on the absorption and translocation processes affecting N assimilation. The… More >

Chan RL

Phyton-International Journal of Experimental Botany, Vol.78, pp. 5-10, 2009, DOI:10.32604/phyton.2009.78.005

Abstract Transcription factors (TFs) are proteins able to specifically recognize DNA sequences in the regulatory regions of their target genes. They bind these specific sequences, an event that leads to the activation or repression of whole signal transduction pathways. In plants about 1500 TFs were informatically identified; identification was mainly based in the presence of DNA-binding domains in the translated sequences. They were classified in families and subfamilies according to several features, including the conservation of the DNA binding domain, the genes structures and the functions they exert. Among transcription factors, several seem to be potential powerful biotechnological tools to improve… More >

Busso CA

Phyton-International Journal of Experimental Botany, Vol.77, pp. 327-350, 2008, DOI:10.32604/phyton.2008.77.327

Abstract Advantages, disadvantages and precautions of using the pressure chamber and thermocouple psychrometers for determinations of plant water potential, and osmotic and turgor pressures are discussed. Comparison of results obtained with both instruments will be influenced by the sampling technique, consistency in both sampling and measurement procedures, and errors inherent to the method itself. In-situ readings of either plant or soil water potential with thermocouple psychrometers are perhaps worthless, or worse (they may even be misleading). Use of thermocouple psychrometers is strictly limited to the laboratory where isothermal conditions can be obtained. The method to determine the water relations of plant… More >

Pincheira-Ulbrich¹ J, JR Rau², E Hauenstein³

Phyton-International Journal of Experimental Botany, Vol.77, pp. 321-326, 2008, DOI:10.32604/phyton.2008.77.321

Abstract We sampled the diversity of trees and shrubs, and built the rarefaction and accumulation species curve in 10 native forest fragments in southern Chile. Results indicated that: (1) there were 23 species in all sampled fragments, (2) species richness increased significantly with fragment size, (3) all fragments require a minimal sampling from 40 to 170 individuals to reach the maximum theoretical species richness, and (4) sampling richness was greater than that theoretically expected (20 species). More >

Castellanos-Pérez¹ E, AG de Soyza², GB Donart³

Phyton-International Journal of Experimental Botany, Vol.77, pp. 297-320, 2008, DOI:10.32604/phyton.2008.77.297

Abstract The study was conducted in the Chihuahuan Desert Rangeland Research Center, 32 km north of Las Cruces, NM, USA. Physiological responses of the shrub Larrea tridentata (DC) Cov. and the perennial grass Muhlenbergia porteri Scribn were determined from the summer 1997 to the winter 1998-99 when they grew together. In the summer 1997, Larrea tridentata competed for water with M. porteri, as shrubs growing alone showed higher integrated photosynthesis than shrubs in competition with M. porteri following a heavy rainfall event. Larrea tridentata had lower water use efficiency (WUE) than M. porteri plants. In the summer 1998, M. porteri had… More >

Bucciarelli A, VN Cambi, CB Villamil

Phyton-International Journal of Experimental Botany, Vol.77, pp. 283-295, 2008, DOI:10.32604/phyton.2008.77.283

Abstract Araujia hortorum (“tasi”) is a native species of South America, invading crops in several countries. It is used as food and in medicine due to its galactogenic properties. Morphoanatomical and micrographic characters of leaves, stems and roots were studied to determine diagnostic characters that allow its identification in the vegetative state. Stomata and palisade parenchyma indexes, stomata location, the proportion and characteristics of palisade and spongy parenchyma and the scarce quantity of idioblasts, resulted in the most relevant, differential characters. More >