[Effect of tillage implements type ,tillage depths and time of nitrogen fertilizer application on some soil properties and peanut growth]

A field experiment was conducted for two years 2011 and 2012 to evaluate the effect of various tillage implements , tillage depths and nitrogen fertilizer timing application on some soil properties, peanut growth. Different implements were used those are: moldboard (MP) , disk ploughs (DP) and chisel (CP). Tillage depth D1 (8-10) cm, D2 (18- 20) cm and D3 (28- 30) cm . Timing nitrogen application are: T1 all nitrogen fertilizer applied at planting ,T2 half nitrogen applied at planting and half at flowering ,T3 all nitrogen fertilizer applied at flowering . The experiment is (split- split plots) designed: tillage implements are main plots tillage depth treatments(split-plots), timing nitrogen application (split-splitplots). The study shows : all tillage implement decreased soil bulk density until, lowest bulk density were(1.30,1.29)g/cm3 for two years respectively at (0-10)cm depth by using moldboard (MP), increasing tillage depth decreased bulk density which associated with increasing soil's moisture . moldboard (MP)facilitate seeds emergence , There was no effect of previous treatments on main branches, but timing of nitrogen fertilizer application T2 increased secondary branches Moldboard increased leaf area , leaf area index three and four months after planting, so that for deep tillage D3(28-30) cm , timing of nitrogen fertilizer application T2 increased leaf area , leaf area index two months after planting. Moldboard plowing(MP) increased matured pods/ plant, so that pods/ plant and seeds/pod increased in the treatment of deep tillage D3(28-30) cm, weight of pods/plant and dry matter accumulation reached best values by using Moldboard plowing(MP) and deep tillage D3(28-30) cm so that for time of applying nitrogen fertilizer T2 ( half at planting and half at flowering). Type of plowing instrument didn't affect crop index nor harvest index those have highest values in treatment of deep tillage D3(28-30) cm and time of applying nitrogen fertilizer T2 ( half at planting and half at flowering), Moldboard plowing(MP) , deep tillage D3(28-30) cm and time of applying nitrogen fertilizer T2 ( half at planting and half at flowering) increased seed index so that for pods productivity which were (3501,3318) kg/h respectively for two season. Deep tillage increased chlorophyll concentration significantly in peanut leave at all growth stages ,but timing application (T1,T2) increased chlorophyll concentration at early growth stage (40 day after planting) . Applying nitrogen fertilizer T2 ( half at planting and half at flowering) increased seeds content of protein , and oil content in the seed increased when nitrogen fertilizer applied at flowering stage T3. moldboard (MP) , disk ploughs (DP) decreased weeds number /m2 so that deep tillage D3(28-30) cm has done at all growing stages , soil nitrogen content 237 increased by using moldboard (MP) , disk ploughs (DP) at (0-10) cm depth , while available K and P increased at this depth by using chisel (CP) , those increased at (10-20) cm depth by using moldboard (MP) , disk ploughs (DP), nitrogen, phosphorus ,potassium decreased at (20-30) cm by using all tillage instruments