الفهرس 
INTRODUCTION
Effect of compost application on plant growthOnly 14 pages are availabe for public view
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Abstract
The investigation was conducted to evaluate three types of plant residues, rice straw (RS), maize stalks (MS) and cotton stalks (CS) as organic fertilizer by using poultry manure as a source of nitrogen. Also three types of microbial inocula, (Effective microorganisms (EM), nitrogran + nitrocompostal (German inocula) and Local inoculum, were tested as activators for activating the decomposition process. The composting mixtures with twelve heaps were prepared. Two pots experiments were conducted to evaluate the product composts 1st experiment with pea plant to study the effect of compost on plant and soil and 2nd experiment with wheat plant to study the residual effect of compost on palnt and soil. There were 5 levels of compost additions according to nitrogen percentage (100%, 75%, 50%, 25% and 0) before sowing, then pots were irrigated and left for 3 days before sowing. A split plot design with three replicates was adopted. The main plots were inocula [Effective microorganisms (EM), nitrogran + nitrocompostal (German inocula) and Local inoculum], while the sub plots were compost application rates for pea and wheat. The obtained results could be summarized as follows: 1. Composting process of plant residues: Temperature: The start of composting and highest temperature was observed after 724 days of composting which rose up to 66, 59 and 66.66 C in treatment with cotton stalks, maize stalks and rice straw, respectively, and then declined gradually. pH: The obtained results showed low pH values at the start of decomposition, then increase gradually. Organic matter and total carbon: The decrease was rapid during the first 28 days then continued to decrease slowly by the end of the composting period, with control (without any inocula), German, Local and inocula, respectively with rice straw, maize stalk and cotton stalk. Total nitrogen: Increases gradually throughout the composting period with control, German, local and EM inocula, with rice straw, maize stalk and cotton stalk, respectively. C/N ratio: The C/N ratio decreased with composting period. Biological changes during composting of different organic wastes: The maximum population of mesophilic bacteria was recorded after 30 days of composting process. The counts of thermophilic bacteria were maximum at 14 days of composting and then decline was observed. Similar trend for mesophilic bacteria was observed with respect to mesophilic fungi population.The maximum counts of colony forming units CFU for thermophilic fungi was found after 14 days of composting in maize stalks inoculated with EM. 2 Greenhouse experiment: Plant measurements: Height of wheat increased with application of compost rates. The effect of compost rates on dry shoot of pea were non proounced, but wheat straw increased with application of compost. Chemical composition in pea and wheat: Total N and its uptake by pea were non pronounced, but with wheat plant total N and its uptake increased with application of compost rates. Total P and its uptake by pea and wheat increased with addition of compost. Total K and its uptake increased with application of compost. Effect of compost on soil properties: Physical properties of soil SP% increased with compost applied as compared with control (without compost). Bulk density decreased with application of compost rates. Compost application increased total porosity of soil. Chemical properties of soil: Soil pH decreased due to compost addition. EC decreased with application of compost rates. Available N after pea and wheat harvesting increased with application of compost. Available P after pea and wheat harvesting increased more than untreated treatment. Available K after pea and wheat harvesting increased with compost application. CONCLUSION: Results indicated that usage of local inoculum was useful for activating the decomposition process with various plant residues as rice straw, maize stalks, and cotton stalks. Also results show that usage of compost (organic fertilizer) became necessary in agriculture process because of compost supply plants with essential nutrients and reduce pollution which caused by using mineral fertilizers.