Effects of three types of organic fertilizers on the growth characteristics and water use efficiency of corn at different levels of soil compaction

Soil compaction is one of the most prevailed limitations for crop growth. The use of organic matters as fertilizer on agricultural soils can reduce the effects of soil compaction and provide the nutrients for the plants. So, a factorial experiment was carried out in a randomized complete blocks design with three replications. The first factor was the source and amount of organic fertilizer (farmyard manure, sewage sludge compost and municipal solid waste compost and each of organic fertilizers at three levels of 0, 15, 30 g/kg soil) and the second factor was two levels of soil compaction (1.2 and 1.7 g/cm3). Results showed that application of all three types of organic fertilizers at both levels of compaction caused an increase in plant dry matter, leaf length and width, stem diameter, leaf chlorophyll index, RWC and WUE, and the maximum of these characteristics was obtained by application of 30 g organic fertilizers. Soil compaction caused a decrease in plant growth and above mentioned characteristics except number of leaves per plant. Application of organic fertilizers and increasing their levels reduced negative effects of soil compaction on corn growth characteristics and WUE; so that at the soil compaction level of 1.7 g/cm3, the corn growth in the 30 g of each fertilizer was greater than the 15 g of them. In order to increasing WUE and corn growth, application of 30 g of farmyard manure or sewage sludge compost or municipal solid waste compost per kg soil can be recommended at similar conditions.