B. Najafi, A.r. Seifi, N.a. Babaeian Jelodar, A.m. Shakib,
Volume 12, Issue 43 (spring 2008)
Abstract
Sorrel (Rumex acetosa L.) is a model dioecious plant in genetic and molecular studies for sex determination. In this research, gus reporter gene transformation to leaf disks of this plant via Agrobacterium tumefaciens was evaluated based on transient expression of this gene. Three strains of Agrobacterium( LBA4404, C58 and EHA101) and two kinds of bacterial suspensions (suspension I: Agrobacterium cells were grown in LB medium with PH 7 and suspension II: the cells were resuspended in MS medium containing 100 mM acetosyringone with PH 5.2) were analyzed in a factorial experiment with 3 replications in Complete Randomized Design (CRD). Also, the effects of three different times of pre-culture of explants (0, 2 and 4 days) were examined. Results showed no significant difference among bacterial strains, whereas suspension I and explants without pre-culture had higher efficiency in gene transformation to this plant. Based on the best treatment, stable transformation with different days of cocultivation was carried out and revealed that the 4-day cocultivation is more efficient than the 2-day cocultivation in gene transformation to Sorrel. The histochemical GUS assay and PCR analysis were done on putative transgenic plants. Results showed that some of these plants contain at least one copy of the transferred gene or genes in comparison with control plants .
M Babaeian, M Haydari, A Ghanbari,
Volume 12, Issue 46 (fall 2009)
Abstract
In order to study the effects of foliar micronutrient application under water stress at three stages of growth on proline and carbohydrate concentrations, grain yield and yield components of sunflower (Alster cultivar), a field experiment in split plot design with three replications was conducted in 2007. Alster cultivar was considered under water stress at three stages of growth (heading, flowering and grain filling) as main plot and seven micronutrient treatments, Fe, Zn, Mn, Fe+Zn, Fe+Mn, Zn+Mn and Fe+Zn+Mn, as sub plots. Results showed, water stress at three stages of growth significantly decreased grain yield, biological yield, 1000 weight seeds, cap diameter and cap weight of sunflower (Alster cultivar). The impact of water stress was more pronounced when applied at grain filling. Use of foliar micronutrient increased grain yield in water stress. On the other hand, use of Mn foliar application had the highest positive effect on yield components and grain yield. Free proline and total soluble carbohydrate concentration were increased under water stress at all of the three stages of growth. The highest concentration of these two components was found on the flowering stage. Foliar micronutrient also increased accumulation of the two components.
