M. Taherian, M. Basafa, A. Nicfetrat, A. Jafari , S. A. Tabatabayi,
Volume 4, Issue 12 (8-2014)
Abstract
For decreasing the effects of Genotype ×Environment (GE) interaction and having more precise selection, the yield and yield stability of selected lines should be evaluated simultaneously. YSi statistic is one of the applied methods for simultaneous selection of yield and yield stability. The objective of this study was to compare result of YSi statistic with other statistics approach such as S2i, CVi, S2di and R2i.Twenty hulless barley lines were evaluated in a randomized complete block design with three replications and in three locations (Neyshabour, Isfahan and yazd) during 2007-2009 crop seasons. Results of combined ANOVA indicated significant effects for Ggenotype ×Environment × year interaction (p= 0.01). Nine lines were selected by YSi method with overall mean of 5.89 t ha-1 grain yield. Overall mean yield of selected lines using only grain yield, yield plus environmental variance (or environmental coefficient of variation) and yield plus coefficient of regression and deviations from regression mean squares were 5.86, 6.01 and 5.85 t ha-1, respectively. Based to the LSD value (LSD=0.87 t ha-1, p=0.05), differences among mean yield (or different selection approaches) were not significant. As a result, with using the YSi statistic (with more emphasis on stability), the cultivar selection process can be done with more confidence.
R. Bayani, A. Saateyi, E. Faghani,
Volume 6, Issue 19 (5-2016)
Abstract
The effect of drought stress and mycorrhizal symbiosis on the colonization, root and leaf phosphorous content, root and leaf phosphatase activity, root volume and area as well as shoot dry weight of a variety of hulless barley were evaluated using a completely randomized experimental design (CRD) with 3 replications. Treatments were three levels of drought stress of 30, 60 and 90% field capacity and two levels of mycorrhizal with and without inoculation. According to the results, the highest value of leaf phosphorous (1.54 mg/g) was observed at mycorrhizal symbiosis against severe drought treatment. Root phosphatase activity was highest (297.9 OD min -1 FW-1) at severe drought stress with mycorrhizal symbiosis which in comparison with mild stress in the presence of mycorrhiza showed 16.6 fold increasing. The control and non-mycorrhizal symbiosis treatments had highest root dry weight (0.091 g). The lowest root volume (0.016 cm2) observed at mycorrhizal symbiosis × severe drought treatment. Generally, Inoculation of barley seed with mycorrhiza at severe water stress could transport more phosphorous to shoot, especially leaf via inducing of leaf and root phosphatase activity. Also, in addition to supply of nutrient sources especially phosphorous for plant, mycorrhizal symbiosis could play an important role in withstanding water stress in plant via increasing of root dry weight and area.
