Effect of mineral fertilizers application combined with rice husk on rice crop and some soil properties of newly reclaimed salt affected soils

A field experiments was carried out in the northern part of Egypt at El-Azdehar village in El-Husienia district, Sharkia governorate Egypt, during summer season of 2013. The soil texture was clay with extreme salinity levels of 7.41dS m-1. The experimental design was a randomized complete block design with three replicates. Eight treatments were assess, namely, control, and different formula of NPK alone or combined with rice husk, T1, (0,0,0), T2 (30, 15, 48), T3 (60, 15, 24), T4 (90, 30, 72), T5 ( T1+rice husk), T6 (T2+rice husk) T7 ( T3+rice husk ) T8 (T4+Rice husk).Rice variety Giza 178 was used in the experiment. Yield and yield-contributing characteristics, N, P and K content and uptake by both straw and grain were determined for all plots. The results indicated that incorporation of mineral fertilizer at formula T4 (90, 30, 72) caused the highest growth parameters, straw, grain yields as well as content and uptake of N, P and K compared to the other rates of mineral fertilizers and control treatments. Application of mineral fertilizers with rice husk was more effective on the above mentioned parameters and the addition of mineral fertilizers as formula (90, 30, 72+rice husk) T8 recorded the highest values of growth parameters, straw, grain yields as well as content and uptake of N, P and K compared to the other treatments. Moreover, the application of mineral fertilizers with rice husk increased the available macro nutrients and improved of some chemical and physical properties i.e., EC, pH, SAR, OM, bulk density and porosity. Furthermore, mineral fertilizers at different rate alone or combined with rice husk succeeded to reduce Na+, higher  N/Na, P/Na and K/Na in straw and grain rice ratio and raised N, P and K + resulted in considerable salinity withstanding.