The agricultural policy in Egypt supports sugar beet farmers to increase the cultivated area and thus increase sugar production and reduce the gap between sugar production and consumption. Therefore, the sugar beet crop occupies an important place in the Egyptian crop cycle as a winter crop not only in fertile soils, but also in poor, saline, alkaline and calcareous soils. A field experiment was conducted at Shandaweel Agricultural Research Station, Sohag governorate, Egypt (latitude of 24.54o N and longitude of 32.94o E) during 2019/2020 and 2020/2021 successive winter growing seasons. The objective of this investigation was to find out the optimal levels of nitrogen and boron to get the maximum productivity and quality of sugar beet. Randomized Complete Block Design (RCBD) using a split-plot arrangement with three replications was used in both growing seasons. Three levels of nitrogen (60, 80 and 100 kg N/fed.) were allocated in the main plots and four boron concentrations (0, 80, 160 and 240 ppm/fed.) were sprayed twice on the beet foliage, grown in the sub-plots at 70 and 100 days after sowing. The results revealed that boron and nitrogen levels had a significant effect on vegetative traits, i.e., chlorophyll a and b, root length and diameter, quality characteristics (sucrose%, Na, K, α-amino N, quality index%) and productivity parameters of sugar beet (root and sugar yields/fed) in the two growing seasons. The highest root diameter and root yield, recoverable sugar yield was produced by applying 80 or 100 kg N/fed. with 240 ppm boron, in both growing seasons. Application of 80 kg N /fed. with 240 ppm of boron gave the highest values of sugar lost to molasses %. On the contrary, Na, K and αamino N were decreased. Supplying sugar beet with 80 kg N/fed. with foliar application of 240 ppm boron is recommended under conditions of the present works in Sohag governorate to obtain the highest recoverable sugar yield, sucrose and quality index of sugar beet.

This study was carried out at Tag Al-Ezz Agricultural Research Station, in 2018/2019 and 2019/2020 seasons to find out the impact of two kinds of water (magnetic and field canal water); number of irrigation (5, 4 and 3 irrigations) and foliar transactions (without, spraying with water, salicylic acid at 300 mg/l and potassium sulphate at 4%) on sugar beet yield and quality characteristic. Each kind of irrigation water was achieved in a separate experiment. In each experiment, a strip-plot design was used with three repeats. Maximum growth, quality traits and yields/fed were recorded by irrigating beets with magnetized water. Supplying plants with 5 irrigations produced the highest values of root and foliage fresh weight, root length and diameter, as well as root and top yields/fed. Irrigating beets four times/season attained highest gross sucrose, extracted sucrose and quality index percentages, as well as corrected sugar yield/fed. Spraying plants with K2SO4 at 4% resulted in the highest values of growth, quality characteristics and yields/fed. Under condition of this study, irrigate sugar beets four times with magnetized water and spraying it with K2SO4 at 4% can be recommended to raise its production and quality traits.

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Stevia (Stevia rebaudiana Bertoni.) leaves have been used in many countries. It called as sweet herb. Stevia leaves have been used as either a sweetener or as a medicinal plant. The aim of this work was to study its mutagenic and antimutagenic potentiality using bacterial assays (prophage induction and transduction). The results showed that the survival percentages of bacterial cells tested with stevia extract at concentration 10% did not changed greatly. The obtained results showed a minor increase in prophage F 116 induction assay, wherease pfu/ml ranged from 1.58 up to 2.34 × 10 4 as a result of using the concentrations from 0.00 up to 20.00% respectively. When applying the Heinemann (1971) equation on transduction analysis, it was noted that the increase than control ranged from 1.03 up to 1.34 folds only when 20% of stevia extract was used. In order to assay antimutagenic response of stevia to a mutagenic compound (EMS), whereas mutagenic index (MI) dropped from 12.06 at 20.00% of EMS up to 3.36 when 10% of stevia extract was added. The results proved that stevia leaves ethanol extract has no mutagenic activity and it has an antimutagenic activity.

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