Nutritional Status and Sufficiency Ranges of Nutrients Based on DRIS Method of Onion Plants (Allium cepa L.) Grown in Sandy Soil

The Diagnosis and Recommendation Integrated System (DRIS) method was employed to monitor the nutrients status of onion plants (Allium cepa L.) grown in sandy soil at winter season in the Nubaria, Behira Governorate. DRIS norms were established for various nutrient ratios obtained from high yield group of onion plants. Seventy two samples of bulb were analyzed for N, P, K, Fe, Mn, Zn and Cu content and bulb yield were recorded of onion farms fromNubaria, Behira Governorate. The forms of expression for different nutrients and their norms were selected, based on the highest variance ratio between low and high yielding group. The results showed that the average yield in the high-yielding group was 16.14ton ha-1, while the average yield in the low-yielding group was 11.18ton ha-1. Theselected DRIS norms of onion plants grown in sandy soil wereP/N: 0.154, K/N: 0.348, N/Fe: 83.45, Mn/N: 0.0015, Zn/N: 0.0017, Cu/N: 0.006, P/K: 0.441, P/Fe: 12.74, P/Mn: 106.5, Zn/P: 0.011, Cu/P: 0.004, Fe/K: 0.035, Mn/K: 0.004, Zn/K: 0.005, Cu/K: 0.002,Fe/Mn: 8.382, Fe/Zn: 7.202, Fe/Cu: 20.34, Zn/Mn: 1.164, Cu/Mn:0.413, Cu/Zn: 0.355. The sufficient ranges for N, P and K were 1.987 - 2.769 %, 0.282 - 0.448 % and 0.704 - 0.944 %, respectively. As well as, the sufficient ranges for Fe, Zn, Mn and Cu were 258.3 - 312.7, 29.72 - 38.64, 34.96 - 44.46 and 11.79 - 16.51 ppm, respectively. Determine the optimum values in bulb are an important indicator of the high quality of the bulbs, becausethe relationship between of those nutrientsand all these vehicleswhich are expressive on bulbquality.