EVALUATING SYMBIOTIC EFFICIENCY OF Mesorhizobium REDUCING SYMPTOMS OF CHICKPEA YELLOW MOSAIC VIRUS

Chickpea (Cicer arietinum L.) belongs to legumes reducing atmospheric nitrogen symbiotically through Rhizobia Spp. into proteins in a process leaves no carbon footprint. However, chickpea is highly susceptible to viral diseases, which limits productivity. Therefore, the current study is conducted, in two seasons (2015/2016, 2016/2017) to evaluate the symbiotic efficiency of Mesorhizobia in reducing the damage occurs in chickpea if was infected by chickpea yellow mosaic virus (CpYMV). For this aim, One viral (CpYMV) and two Mesorhizobial isolates (MS3All, MS8All) are isolated from open-fields of chickpea plants. Three chickpea experimental lines (F.07-268, F.07-258 and F.0744) and one Egyptian cultivar (Giza195) are dually infected by CpYMV and either of MS3All and MS8All. Then, infected plants are grown in pots in open-air at the cultivation area of the Faculty of Agriculture, Ain-Shams University (Shoubra). The results indicated that the viral infection led to a reduction in the dry weight of root (DWR) and shoot (DWS), the ratio of root-to-shoot (RSR) dry weight, the nodule counts (NN), the photosynthetic pigments and the nitrogen content (N2). Interestingly, the dry weight of nodules (DWN) is significantly increased in dually infected plants. Uniinoculated Chickpea using either of the two isolates of Mesorhizobia showed significant increase in all phenotypic parameters when virus infection is included; except for DWN that decreased com pared to control viral-infected plants but no mesorhizobia. The current study suggests that bacterial inoculation using Mesorhizobia is significantly reduced damaging effects of the virus on chickpea. Moreover, the MS3All isolate is suggested the more effective than MS8All and the experimental chickpea lines F.07-258 and F.07-44 had the highest significant levels of N2 for shoot than F.07-268 and Giza195 lines

MICROPROPAGATION AND START CODON TARGETED CHARACTERIZATION OF FOUR STEVIA CULTIVARS IN EGYPT

calorie crop and commercially used as a non-caloric sweetener for diabetic patients. It is also used as cosmetic ingredient, pickling agent, and dentifrice. Four cultivars (Spantia, Shou2A3, China, and High Sugar) of stevia were included to optimize in vitro micropropagation. Four different combinations of hormonal treatments were investigated [6-benzylamino purine (BAP) + Kinetin (Kin) (0.25 + 0.25 mg/l); Forchloefenuron (Cppu) + Kin (0.25 + 0.25 mg/l); Cppu+ Kin (0.5+0.25 mg/l); and the control medium (hormone-free)]. Out of the different media components, the hormone-free medium produced the best performance of explants. The analysis of variance showed that the control treatment was the most significant for all traits except the number of branches per cutting. Hardening of rooted plants was performed in plastic pots with 70% survival percentage during acclimatization. Molecular characterization, of the four stevia cultivars, was conducted using 11 SCoT primers. The SCoT analysis resulted in 122 amplicons, of which, 62 amplicons (51%) were polymorphic. The range of polymorphism was between 6 % and 91 %. The range of polymorphic amplicons per primer was between one and 12 amplicons. The SCoT-16 produced the highest number of polymorphic bands (12). Meanwhile, the SCoT-24 produced the least polymorphism (6 %). The current study provides a new micropropagation system with low cost, high efficiency, and hormone-free application. Additionally, the study provides the first molecular characterization of stevia using SCoT marker system. Finally, SCoT markers associated with cultivars having high and low contents of stevioside can further be validated by marker-assisted breeding studies