Luján-Rangel R¹, E Olivares-Sáenz², RE Vázquez-Alvarado², L Garza-Ocañas¹, O Torres-Alanís^1(†), HJ Garza-Ulloa¹

Phyton-International Journal of Experimental Botany, Vol.81, pp. 247-253, 2012, DOI:10.32604/phyton.2012.81.247

Abstract Karwinskia parvifolia Rose synthesizes a toxin (PA1), which might be used to treat some types of tumors. Variability from 16 plants of K. parvifolia and the effect of nitrogen was evaluated on its dry fruit yield. The experiment was carried out using a crossover design, two treatment sequences and two production cycles. Collected data were: dry fruit yield (DFY), dry fruit weight (DFW) and dry endocarp weight (DWE) per plant. During Cycle 1, the group of plants that received additional nitrogen (CN) produced higher yields than the group that received no additional nitrogen (SN). Ratios of CN/SN were 1.68 (DFY),… More >

Liu ZG^1,2, YL Cai^1,2, K Li^2,3

Phyton-International Journal of Experimental Botany, Vol.79, pp. 81-86, 2010, DOI:10.32604/phyton.2010.79.081

Abstract Induced responses to herbivory are physical, nutritional, and allelochemical traits that change in plants following disturbances, and reduce the performance and/or preference of leaf tissues on herbivores. This study gave evidence to the induced defense theory through the simulated herbivory in Schima superba, one of common dominant trees in subtropical evergreen, broadleaf forests in southern China. Results showed that leaves damaged at the beginning of leaf expansion would develop into having a larger area, higher toughness and higher tannin concentrations, but a lower water content compared with control leaves. As a result, they experienced lower herbivory rates than controls. These… More >

Rui Yu-kui, Zhang Fu-suo, Shen Jian-bo

Phyton-International Journal of Experimental Botany, Vol.78, pp. 101-104, 2009, DOI:10.32604/phyton.2009.78.101

Abstract Nitrogen fertilization has played a significant role in increasing crop yield, and solving problems of hunger and malnutrition worldwide. However, excessive nitrogen inputs do not significantly increase crop yields but may lead to many serious environmental problems. The effects of nitrogen fertilization rate were studied on heavy metal content of corn grains. Our results show that nitrogen fertilization management is beneficial for reducing production costs, protecting the environment, and improving the quality of farm products. More >

Brevedan¹ RE, MI Aveldaño², MN Fioretti¹, MA Varillas², SS Baioni¹, HR Mirassón³, IR Palomo¹

Phyton-International Journal of Experimental Botany, Vol.78, pp. 49-52, 2009, DOI:10.32604/phyton.2009.78.049

Abstract Two experiments were conducted under greenhouse conditions to study the influence of P deficiency on nitrogen nutrition of non-nodulated soybean. There was a reduction of N and P content in P deficient (P-) plants of almost 50% after 50 days. During this period, dry matter of these plants was reduced by 33%. Nitrate reductase activity and shoot nitrate content were lower in Pthan in P+ plants. Seventy five percent of nitrates in P- plants were in the roots. Nitrate accumulation in roots would be due to the lower nitrate reductase activity in this organ and a reduced water flux to… More >

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 >

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 >

Brevedan RE, MN Fioretti, SS Baioni, IR Palomo, H Laborde

Phyton-International Journal of Experimental Botany, Vol.76, pp. 153-167, 2007, DOI:10.32604/phyton.2007.76.153

Abstract A long-term study was conducted at different locations of Southwestern Buenos Aires to evaluate the effects of N fertilization at different growth stages of soybean on yield, plant nitrogen concentration and seed protein and oil concentrations. Yields were increased in six out of ten trials, and the response was highest with N fertilization at the beginning of grain development (R5). Different nitrogen sources were applied at seeding which gave higher yields and increased seed protein content than the non-fertilized, non-nodulated treatment. Urea was the most effective N source. More >

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

Phyton-International Journal of Experimental Botany, Vol.76, pp. 143-152, 2007, DOI:10.32604/phyton.2007.76.143

Abstract The objective of this work was to determine the effect of deficiency versus toxicity of N on biosynthesis of proline in fruits of green bean plants (Phaseolus vulgaris L. cv. Strike). Nitrogen was applied to the nutritive solution in the form of NH₄NO₃ at 1.5 mM (N1), 3.0 mM (N2), 6.0 mM (N3, optimal level), 12.0 mM (N4), 18.0 mM (N5), and 24.0 mM (N6). Nitrogen deficiency (N1 and N2) was characterized by having lower proline accumulation in pods and seeds, mainly because proline degradation was stimulated by the enzyme proline dehydrogenase. On the other hand, N toxicity (N4, N5,… More >

Luján-Rangel¹ R, E Olivares-Sáenz², RE Vázquez-Alvarado², L Garza-Ocañas³, O Torres-Alanís³

Phyton-International Journal of Experimental Botany, Vol.76, pp. 61-77, 2007, DOI:10.32604/phyton.2007.76.061

Abstract Karwinskia parvifolia (Kp) and Karwinskia humboldtiana (Kh) are poisonous plants of the rhamnacea family. Toxicological and clinical studies performed with one of the compounds present in the fruit [peroxisomicine A1 (PA1)] suggest its possible pharmacological usefulness in the treatment of certain types of cancer. This is why these plants are cultivated: to increase their productivity of PA1. We studied the effects of nitrogen and species on seed viability. The germination curve was determined for Kp with (Kp-WN) and without (Kp-NN) nitrogen, and for Kh without nitrogen (Kh-NN) using the probit model. This is characterized by the probability of germination in… More >

Wang XG¹, Wuyunna^1*, CA Busso², YT Song¹, FJ Zhang¹, GW Huo¹

Phyton-International Journal of Experimental Botany, Vol.87, pp. 123-132, 2018, DOI:10.32604/phyton.2018.87.123

Abstract Chemical elements, such as carbon (C), nitrogen (N) and phosphorus (P), are major limiting nutrients in arid and semiarid grasslands and their stoichiometry (C:N:P) is a very important ratio to determine. In addition, it is critical to understand how plant stoichiometry responds to multiple environmental factors at the species level. In this study, we conducted a greenhouse experiment to investigate the effects of salt stress (4 g NaCl/kg soil), drought (35% of the soil water holding capacity) and N addition (10 g N/m²), as well as their interactions, on C, N and P concentrations and C:N:P ratios in two dominant… More >