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Nowadays, using sewage wastewaters in the irrigated agriculture is commune creating hazardous environment impacts. Assessment of these negative effects is vital issue to prevent heavy metals to be introduced in the food chain. Field and laboratory studies were conducted at Arab-El-Madabegh village, Assiut Governorate, Egypt, in order to evaluate the heavy metals concentrations in the edible parts of lettuce and spinach plants which irrigated with sewage water (SW). The obtained results indicated that, the soils of the studied site were contaminated by heavy metals. Zinc, Cu, Pb, Cd and Ni concentrations in the edible portions of the studied vegetables plants ranged between 75-110, 15 -17, 2 -5, 1.0 -3.5 and 1.0 -2.5 mg kg −1 , respectively. The obtained results showed that the concentrations of Zn, Pb, Cd and Ni in the edible parts of the studied plants were higher than the permissible limit levels but those of Cu were within the safe limit levels. It is worthy to mention that the irrigated edible vegetable crops with SW should be avoided. This study highlights the potential hazard for human health due to the uptake of high concentrations of heavy metals especially Zn, Ni, Cd and Pb by the studied vegetable crops .

The population acceleration and better lifestyle submit new challenges for wheat researchers to breed wheat (Triticum sativum) cultivars with upgraded yield, quality, and resistance against abiotic stresses such as drought, so exploiting all available natural relatives of cultivated wheat and introducing even sensitive ones may be a useful approach to save time and efforts. Normally, the seedling stage is highly drought vulnerable, but for sensitive cultivars, the situation is more frustrating. We examine the potentiality of two regulating hormones in the upregulation of two wheat cultivars varying in their drought susceptibility at the seedling stage comparatively evaluated by morpho-physiological traits as indicators of drought tolerance. All the studied traits revealed cultivardependent variation in response to water deficit where cv. Sids 1 was tolerant and cv. Beni-suef 5 was sensitive. Shoot/root ratio, total water content, total dry weight, chlorophyll stability, total osmotic potential, osmoregulatory components, viz., soluble carbohydrates, soluble proteins and proline, membrane damage trait in terms of LOX, antioxidant defense system enzymatically in terms of APX, CAT, POD, SOD, and total antioxidant as drought tolerance indicators were the troubling shot due to water shortage in both cultivars. The damaging impacts of water deficit on these traits were conceived for sensitive cultivar compared with the tolerant one. Exogenous application of jasmonic acid (JA) or kinetin (K) efficiently conferred drought tolerance to sensitive cultivar to withstand harsh conditions in earlier stages and to perform comparably with tolerant ones. Applied hormones prompted unequivocal inversion from a state of downregulation to upregulation regarding all drought tolerance traits via reallocation of photoassimilates to vegetative sinks, thus promoting growth, increasing the accumulation of some osmoregulation compounds and thus increased tissue vigor and regulated the activity of antioxidant enzymes as well as morphological modulation attained by the restoration of shoot/root ratio. The results would promisingly be supportive of research programs seeking to develop antidrought stress practices for sensitive wheat cultivars.

Soil amendments may increase the slate tolerance of plants consequently; it may increase the opportunity of using saline water in agricultural production. In the present pot trial, the effects of biochar (BIC) and compost (COM) on roselle (Hibiscus sabdariffa L.) irrigated with saline water (EC = 7.50 dS m−1) was studied. Roselle plants were amended with biochar (BIC1 and BIC2) or compost (COM1 and COM2) at rates of 1 and 2% (w/w), as well as by a mixture of the two amendments (BIC1+). The experiment included a control soil without any amendments. Biochar and compost significantly enhanced the soil quality and nutrients availability under saline irrigation. Compost and biochar improved the degree of soil aggregation, total soil porosity and soil microbial biomass. BIC1 + COM1 increased the soil microbial biomass carbon and nitrogen over the individual application of each amendments and control soil. BIC1 + COM1 increased the activity of dehydrogenase and phosphatase enzymes. Growth of roselle plants including: plant height, shoot fresh and dry weight, and chlorophyll were significantly responded to the added amendments. The maximum sepal’s yield was achieved from the combined application of compost and biochar. All the investigated treatments caused remarkable increases in the total flavonol and anthocyanin. BIC1 + COM1 increased the total anthocyanin and flavonol by 29 and 17% above the control. Despite the notable improvement in soil and roselle quality as a result of the single addition of compost or biochar, there is a clear superiority due to mixing the two amendments. It can be concluded that mixing of biochar and compost is recommended for roselle plants irrigated with saline water.

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