The adverse effects of sea water salinity on number of nodules, nitrogen content, nitroginase activity, Chlorophyll a and b content, proline accumulation and protein pattern of faba bean plants (Vicia faba commercial cultivar Nubaria 1) were investigated. Faba bean plants were irrigated with sea water at 20, 25, 30, 40 and 50% concentrations and inoculated with rhizobial isolate ARC307 or with gamma rays treated isolates namely; ARC1, ARC2, ARC3, ARC4, ARC5, ARC6 and ARC7. Nodules number, nitrogen content, nitroginase activity and chlorophyll a and b content parameters were decreased by increasing sea water salinity with all used isolates, while proline accumulation parameter increased. At the same time, ARC2 isolate showed the highest values for these parameters above all isolates including the parental isolate ARC307 at all studied concentrations except for proline accumulation parameter, it was the least. Therefore, ARC2 considered as a promising isolate for salt tolerance. Salinity enhanced the occurrence of particular novel proteins in faba bean plants infected with ARC2 isolate.

Thirteen Rhizobial isolates were recovered from the root nodule of Faba bean (Viciae faba L.) grown in different geographic locations and soil properties in Egypt. The tested isolates were identified as R. leguminosarum sv. Viciae on the bases of morphological, biochemical characteristics and sequences of the gene encoding 16s rRNA. Rhizobium isolates were tested for their ability to utilize different carbon sources. Mannitol and Glucose were the best source of carbon. All tested isolates from Vicia faba differ in IAA production. The maximum amount of IAA production was in the range of (2.04 μg/ml) for Al Arish isolate to (7.5 μg/ml) for Ismailia isolate among the studied isolates. A great ability to degrade Roundup herbicide among the tested isolates was observed. Sues City isolate was the best active degrading Roundup herbicide on plates. All of the tested isolates showed resistances to (25 and 50 mg/ml) expect isolate RL7 was sensitive at high Roundup herbicide concentration, while isolates RL5, RL6, RL8, RL10 and RL13 were the most tolerance at 50 mg/ml herbicide. South Sinai, Zefta, Rafah, El-Menia, Cairo and Ismailia isolates shared a common band with mol. wt. of 70 KDa. New protein types were detected due to the differential response of the five isolates to the effects of the environment stress.