el-Khaimah, Qalyubiah Governorate. The aim of the current investigation was to study the impact of three planting dates (18-Dec, 7-Jan and 27-Jan), three irrigation levels at 60, 80 and 100% of irrigation water requirements (IR) and their interaction on potato crop productivity. 9 treatments were obtained by combination of different planting dates and irrigation levels.Planting dates were arranged as the main plots, while, irrigation levels were arranged in the sub plots, The obtained results indicated that the highest tuber yield was obtained by the first planting date (18 Dec.) during both studied seasons, While, The highest plant growth parameters and tuber yield per plant were obtained by 100% followed by 80% irrigation level during both seasons. However, the interaction effectindicated that first planting date (18-Dec) combined with 100 % irrigation level gave the highest potato tuber productivity than the other treatments, whereas the interaction of first planting date 18-(Dec) combined with 80% irrigation level gave the best for water use efficiency compared to the other treatments during both tested seasons.

The present study was carried out at Farm of Agricultural Research Center in Gemmeiza Agricultural Research Station, Egypt, El-Gharbia Governorate during the two consecutive winter seasons of 2016/2017 and 2017/2018.To evaluate effect of intercropping garlic bulbs on black cumin plants on microbial community of soil, productivity and quality of both crops. And there are 4 levels of intercropping as main plots (50%, 66%, 99%) intercropping, solocropped plants) and the 3 nitrogen fertilization levels were as subplots (50%, 75%, 100% nitrogen) were considered. The obtained results showed the importance of intercropping black cumin plants on garlic plants in improving the growth and yield of black cumin seeds, fixed oil and of volatile oil black cumin plants compared to solocropped plants. The treatment (T6) is increased the weight of (the seeds of one capsule, 1000 seeds, of the capsules / plant, the seeds / plant, the seeds / plot, the seeds / fedd.) and the number of capsules / plant, for black cumin plants and increased the fresh and dry weight both of the head (gm) and dry weight (Kg) / fedd. for garlic bulbs, while the treatment (T5) is resulted in an increase in the volatile oil%, the weight of (the volatile oil and the fixed oil) L/ fedd. on both seasons for black cumin plants and increase the organic acids in the fixed oil and increased the volatile oil % and the weight of volatil oil L/fedd. for garlic bulbs. The treatment (T9) is increased the fixed oil % for black cumin, while (T4) is increased total carbohdrates % in bulbs.