Seed priming improves vigor, but priming agents may differ greatly in their effectiveness. The present study was performed to unravel the physiological basis of vigor improvement by priming sunflower achenes with pre-optimized levels of hydrogen peroxide (H2O2), salicylic acid (SA), thiourea (TU), gibberellic acid (GA3), ascorbic acid (AA), sodium chloride (NaCl), freezing and heating. Most of ...

Many changes in development, growth, hormone activity and environmental stimuli responses are mediated by mitogen-activated protein kinase (MAPK) cascades. However, in plants, studies on MAPKs have mainly focused on MPK3, MPK4 and MPK6. Here, a novel group B MAPK gene, GhMPK11, was isolated from cotton (Gossypium hirsutum L.) and characterized. Both promoter and expression pattern analyses reve...

The genetic control of dormancy is poorly understood in most plant species, but dormancy is a prominent feature for the potato industry. We used the microtuber system, in which tubers were produced in vitro and stored at 20°C, to perform quantitative trait locus (QTL) analysis for dormancy and gibberellic acid (GA3) content in an F1 population consisting of 178 genotypes derived from an intersp...

The accumulation of a considerable quantity of gibberellin fermentation residue (GFR) during gibberellic acid A3 (GA3) production not only results in the waste of many resources, but also poses a potential hazard to the environment, indicating that the safe treatment of GFR has become an urgent issue for GA3 industry. The key to recycle GFR is converting it into an available resource and removi...

Effect of sodium arsenate (Na2HAsO4.7H2O) on the growth and activity of few oxidizing enzymes of mungbean seedlings was investigated and it was found to have drastic effects on the growth and biochemical metabolism of germinating mungbean (Vigna radiata (L.) Wilczek cv. B-105) seedlings. With the increase in concentration of sodium arsenate (5μM, 10μM and 20μM) significant decrease in seedling ...

Xyloglucan endotransglycosylase (XET) activity extractable from internodes of tall and dwarf varieties of pea (Pisum sativum L.) was assayed radiochemically using tamarind seed xyloglucan as donor substrate and an oligosaccharidyl-[3H]alditol as acceptor substrate. Internodes I and II showed little elongation during the period 15 to 21 d after sowing; XET activity remained relatively constant a...

Gibberellins (GAs) are involved in the regulation of numerous developmental processes in plants including zygotic embryogenesis, but their biosynthesis and role during somatic embryogenesis (SE) is mostly unknown. In this study we show that during three week- long induction phase, when cells of leaf explants from non-embryogenic genotype (M9) and embryogenic variant (M9-10a) were forming the ca...

Prolonging the marketing period of peach fruits in Egypt through introducing new cultivars, breaking dormancy early or delaying maturity of some cultivars by safe compounds would increase the growers' profits. This study was conducted during two successive seasons 2005 and 2006 by using "Desert Red" peach cultivar (Prunus persica L.) grafted on Nemaguard rootstock. Trees were grown at El-Noubar...

Submerged aquatic macrophytes such as Potamogeton crispus can absorb large quantities of nutrients from sediment and water, and therefore mitigate pollution and improve water quality of polluted lakes. Turions are the main propagules of P. crispus; their formation is an important process in the life cycle of the plant and relates closely to the population dynamics of the species in lakes. The c...

Inflorescence development of the 'Hass' avocado (Persea americana Mill.) was investigated at the macro and microscopic level. Near the end of shoot extension, two secondary axis meristems were present in the axils of inflorescence bracts. The primary axis meristem changed shape from conical to flattened to conical followed by the initiation of additional bracts and associated secondary axis inf...