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This work is part of a larger research project studying the immune responses of a variety of plants. Once image-based (unpublished data) and another time, as in this study, biochemical parameters based. Plant models included three metabolically different plants, Vica faba L. (C3), Zea mays L. (C4), Mesembryanthemum L. (CAM). Pathogen models had Alternaria alternate and Pseudomonas syringe. All of which, along with the control treatment, represent nine plant-pathogen systems applied with three replicates of each studied species. To investigate the extent to which the immune response is transferred from infected leaves to uninfected leaves on the same plant, several physiological and biochemical immune responses were examined, including: two plant hormones, abscisic acid and Salicylic acid, and two active enzymes, Catalase enzyme and Peroxidase enzyme, two free radicals, ROS and H2O2. Results show that The studied hormones were significantly affected by the type of plant metabolism and the type of pathogen, sometimes by an increase and sometimes by a decrease in which ABA and SA increased in C3 and CAM plants when infected by Alternaria and varied when infected by pseudomonas syringe. At the same time, both ABA and SA decrease in C4 plants. The studied enzymes did not follow a specific pattern of increasing and decreasing response to a bacterial or fungal infection. Still, they differed significantly between plants of different metabolism according to the type of pathogen causing the infection. Infection of all three studied plants by Alternaria alternate and Pseudomonas syringae did not cause any significant changes at p≤ 0.05 in the free radical production of the leaves for both ROS and H2O2.

This work is part of a scientific project that aims to study the effect of adding yeast (Saccharomyces cerevisiae) on growth, productivity and nutritional value of two varieties of lettuce (Lactuca sativa), planted in a hydroponic system. Here we extend experimental approaches to detect the Rhizophagy process induced by added S.cerevisiae to hydroponic nutritive solution. An Laboratory anatomical study was conducted to detect and investigate the occurrence of Rhizophagy phenomenon induced by yeast cells. Results showed that the yeast cells aggregate around the root cells of lettuce, and then enter the cells, followed by digestion and disappearance.

A field study was conducted in Diwaniyah city at the winter season 2017-2018 for studying the effect of the set size and Nanocarbon compounds on the growth and yield of onion plant Allium cepa L. three set sizes (small, medium and large ) and two Nanocarbon concentrations(0 and 500 mg / L) were used in the experiment. A range of vegetative traits including plant height and number of leaves, total leaf area, chlorophyll rate and number of roots were studied. In addition to yield characteristics that includes number of bulbs, fresh and dry weight and productivity. The results showed that set size and Nanocarbon compounds significantly affected the vegetative growth of the studied plants. plants planted with large sets and treated by 500 mg/L Nano-carbon scored the best results for plant height, chlorophyll rate and leaf area. In which, it recorded the highest plant height (70.1 cm), and the maximum chlorophyll content (80.18 mg/ml), and the maximum leaf area (5.21 cm2), compared to control treatment which scored (26.5 cm), (47.59 mg/ml), (2.21cm2) for the same parameters above. The number of leaves/plants increased with the increase in set size while it decreased when treated by all Nano-carbon concentration. The large set gave the highest number of leaves/plants when not treated by Nanocarbon as it reached 8.5 leaves, in comparison with those treated by Nanocarbon and the comparison treatment which reached 7.1and 7.5 respectively. The plants planted with medium sets and treated by (500 mg/L) of Nanocarbon gave the largest number of roots/plant reached 90.1 root, compared to control plants, which have 68 root only. large set plants treated by 500mg/L. carbon nanotubes increased The number of double bulbs, fresh weight, dry weight and productivity increased to 7.9, 31.01g, 9.0 g and 70.017respectively in compare to control plants which scored 1.8, 27.59g, 2.531g and 64.636 for the same parameters respectively.