The main objective of this research is to promote the reuse of wastes resulting from different manufacturing processes such as fruit peels (e.g. banana and orange peels) as substitutes (at least partially) of mineral fertilizers. This might have positive effects in maintaining human health and reducing environmental pollution. Moreover, to compare the use of these wastes with commercial organic fertilizer i.e., compost made by Nile Company to meet the needs of tomato plants from nitrogen (N) and potassium (K) elements. To achieve the goal, two experiments were conducted. The first was an incubation experiment, which was designed to compare the organic fertilizer compost of Nile Company and the powdered banana and orange peels. The second was a field experiment achieved at the Faculty of Agriculture, Ain Shams University. Obtained results of the incubation experiment showed increases in nitrogen content by 16 to 31% and potassium by 12 to 24% due to using grinded banana and orange peels as compared to the compost treatment. Moreover, in the field experiment the concentration of nitrogen (N) and potassium (K) at different plant growth stages whether in soil or plant did not differ significantly between soil plots fertilized with mineral fertilization and those fertilized with banana and orange ones. On contrary, potassium concentration was found higher in the soil fertilized with organic fertilization than that fertilized with mineral fertilization. It has also been found to us that there are no clear significant differences between tomato fruits resulting from mineral fertilization of the ground and those that were fertilized by the mixture of banana and orange peels in terms of the ratio of nitrogen and potassium, weight, size and density of the fruit and other characteristics except for the total salts percentage, which was less Fruits fertilized with a mixture of banana and orange peels

Two field experiments were carried out during two summer seasons of 2013 and 2014 years at the Experimental Farm of Kaha Station, Qalubia Governorate to study the effect of using three irrigation intervals (7, 15 or 21 day) and five treatments of water absorbent substrates as adding to soil before transplanting ,i.e. (without substrates (control), SAP at 15 kg/fed., SAP at 20 kg/fed., compost at 5 t/fed. and compost at 10t/fed.) on sweet  pepper plants c.v. Mohanad and the effect of that on growth, yield, physical and chemical characters of sweet  pepper fruits. The results indicated that, the highest values of all vegetative growth parameters, yield and yield components were registered by the treatment of 7 days or 15 day irrigation intervals. Concerning of using water absorbent substrates, it was found that, pepper plants grown in the soil fertilized at 10 t/fed. or treated with super absorbent polymer (SAP) 20 kg/fed., respectively gave the highest values of vegetative growth parameters, yield and yield components.It is obvious that the plants fertilized at 10 t/fed. and irrigated every 7 days gave the highest values of fruit length, fruit diameter, fresh fruit weight and total yield. While, plants treated with SAP at 20 kg/fed. and irrigated every 15 day gave the highest values of fruit diameter and fresh fruit weight, but the differences did not reach to significance level for fruit length and early yield in both growing seasons. On the other hand, compost at 10 t/fed., compost at 5 t/fed. and SAP at 20 kg/fed. with irrigation every 21 day were the best treatments for yield and yield components of pepper plants. Generally, it can recommend by using compost at 5 t/fed., or super absorbent polymer (SAP) at 20 kg/fed. with irrigation every 15 days and this mean that increased the irrigation period without any injury or statistical effect on the fruit crop to obtain high pepper fruit yield  with height quality and height net income to the growers.

Two field experiments were conducted on clay loam soil during the two successive seasons, summer season 2017 using maize plants and winter season 2017/2018 using barley plants at El-Gemmeiza Agricultural Research Station, El-Gharbia Governorate to evaluate the direct and residual effects of compost rates mixed with the surface soil layer to 10 cm or added in 30 cm mole depth, arranged in parallel orientation with respect to one another and spaced at 3 m apart besides the nitrogen fertilizer rates on improving some soil chemical properties. Furthermore economical analysis was done by calculating the net income for every treatment to determine the economical treatment. The rates of compost were 0.0, 2.5, 5.0 and 7.5 Ton fed-1, while the nitrogen rates were 0.0, 50, 75 and 100 % of the recommended dose for every growing crop. The experiments were conducted in a split-split plot in a randomized complete block design (RCBD) with three replicates. Results can be summarized as follows: 1- All treatments slightly decreased the soil reaction (pH) in the two growing seasons. 2- Soil salinity (EC), soluble cations and anions and total soluble salts (TSS) significantly increased by increasing nitrogen or compost rates and significantly decreased by increasing application depth. On the other hand, SAR values were significantly decreased with all treatments. 3- All treatments led to significant increases in Ex. Ca, Mg, K and cation exchange capacity (CEC), whereas Ex. Na and ESP were significantly decreased with all treatments in the two seasons. 4- All treatments clearly enhanced total nutrients (N. P and K) of the investigated soil. Also, Organic carbon (O.C, %) and C/N ratio were significantly increased with all treatments. 5- According to the economical analysis, the application of 5 ton compost fed-1 in 30 cm mole depth with 100 % the recommended dose of nitrogen fertilizer for every crop was the best treatment compared with the other treatments, since it gave the highest net income (16809.80 L.E fed-1). 6- Therefore, it is more useful to use those treatments (compost rates at 30cm mole depth with nitrogen fertilizer) to get a markedly improve in chemical properties which reflect on higher yield.

Composting technique is considered as one of the environmentlly friendly methods used for recycling the excess residues of rice straw ( RS) and solving the environmental problems of olive pomace (OP) by-product of the olive oil industry. For this purpose, three compost piles were made from mainly rice straw, different ratios of olive pomace and some agricultural wastes viz. tomato hallum, banana residues and farmyard manure to evaluate the stability and maturity of composted materials during 90-day composting period. The first pile (A) was made of 60% RS+10% OP+10% tomato hallum+10% banana residues+10% farmyard manure, the second pile (B) wase made of 50% RS +20% OP+10% tomato hallum+ 10% banana residues+ 10% farmyard manure while the  third pile (C) was made from 40% RS + 30% OP10% tomato hallum+ 10% banana residues+ 10% farmyard manure. Representative compost samples were taken after 15, 30, 45, 60 and 90 days of the composting process. The results revealed that slight increase in temperature occurred through the first 2-3 days of composting to reach  the maximum values at 30 days of composting (thermophilic stage). All the composts showed a more pronounced increase in pH, EC, bulk density and total nitrogen, while total organic carbon significantly declined with composting progress. Consequentially, the C/N ratios became narrowed during composting process where they reached 18.80 for pile C. At maturity stage, the greatest values of humification parameters (Humification index, Humification degree and Humification rate) were obtained by pile C followed by pile B. Meanwhile, the ratio of  NH4+/NO3- as an indicator to nitrification process, Extinction coefficient (E4/E6) as well as CO2 rate decreased gradually to reach the minimum values. Finally, the highest values of germination index (92.22 and 95.39%) were achieved with pile C for cress and barley seeds, respectively

The aim of this research is to investigate the influence of balance between organic and mineral fertilizers on morphological and predictive charac-teristics of potato for two seasons, through the application of averages: (25 – 50 – 75 and 100) Ton / Hectare from compost of wheat and peanut which mixed successively with the percentage from mineral typical fertilizers (75 – 50 – 25 – 0 %). The results showed the distinguished effect of mineral fertilizer on morphological and prodictive characteristics of tubers in comparison with mixed or single organic fertilizer. The results showed also the positive effect of increasing the percent-age organic manure or its single use in the soil on the examined variables. However, the specific effect of organic fertilizer varied, so the compost of wheat produced an increase of examined varia-bles. This divergence of results was agreed with certain modifications of soil variables

A field experiment was carried out in a newly cultivated soil at Falouga, El-Tahrir province, Behira governorate during the summer season (Spring plantation)of 2003 to investigate the effect of different organic manures (i.e. compost, F Y Mor town refuse) each at rate of 20 ton/fed combined with the half recommended doseof mineral fertilizer (NPK) or 2 tons of chicken manure compared with the additionof the recommended dose of N P K at rate of 900, 400 and 200 Kg/fed ammoniumsulphate, calcium superphosphate and potassium sulphate respectively. Applicationof organic manures, i.e. compost, FYM or town refuse each at the rate of 20tons/fed combined with half amount of mineral fertilizer or 2 tons of chickenmanure, increased total microbial count in soil at 60 days after planting compared toboth uncultivated soil and chemical fertilized treatments. In this regard, the highestbacterial count was noticed in case of using FYM + chicken manure, while thehighest count for total fungi and actinomycetes were recorded in the treatment of 20tons compost + half amount of chemical fertilizer (NPK). In addition, using 20 toncompost + 2 tons of chicken manures/fed, reflected the highest dry matter yield,total nitrogen, phosphorus and potassium content in plant foliage as well as totaltuber yield of potatoes compared with other tested treatments.

Superior grapevines fertilized with compost, biofertilizers namely (Bacillus megatherium, Bacillus curculanse and Azotoacter Chroococcum), humic acid and two slow release fertilizers namely ( rock phosphate and feldspar ) as a partial replacement of mineral N fertilizers during 2013 and 2014 seasons. Using all substitutes of mineral N fertilizers was favourable than using mineral N alone in enhancing all growth characters, total chlorophylls, nutrients, yield and berries characteristics. Both nitrite and nitrate in the juice were greatly declined in all N management treatments that included the application of all N sources. The best results with regards to yield and berries characteristics of Superior seedless grapevines were recorded on  vines that received 60g N, 60g P and 120g K/ vine/ year ( mineral sources) plus compost II ( 40% cattle manure + 60% rice straw ) at 16 kg./ vine+ the three biofertilizers namely Bacillus megatheium, Bacillus circulanse and Azotobacter chroococcum  + humic acid each at 10ml./ vine/ year.

Pot trials were conducted under plastic house condition during two successive seasons of 2013/2014 and 2014/2015, at the experimental site of Central Laboratory for Agricultural Climate (CLAC), Agricultural Research Center, Giza, Egypt. The present study aims to determine the partial replacement of mineral nitrogen fertilization of tomato by nitrogen fixing bacteria with or without adding compost in sandy soil. Tomato seedlings (Lora F1Hybrid) were transplanted during the first week of October into plastic pots (30 cm diameter) filled with 10 kg of sandy soil. Three rates 25, 50 and 75% of the recommended mineral nitrogen in the nutrient solution for tomato with adding compostat 2% and nitrogen fixing bacteria (Azotobacter chroococcum and Azospirillium brasilense) at 20 ml/plant either individually or in combinationswere investigated on growth, mineral composition and yield of tomato plants compared to 100% of recommended nitrogen only (control). The plants were irrigated daily by drip irrigation and received 200 ml/plant of nutrient solution twice a weekly. The results showed that using 50 or 75% of N-mineral fertilizer + compost + nitrogen fixing bacteria gave the highest values of growth, mineral composition and yield of tomato. It is recommended that 50% of nitrogen mineral fertilizers for tomato plants could be replaced by nitrogen fixing bacteria in presence of compost, which in earn, reduce environment pollution caused by extensive application of mineral nitrogen fertilizers.