Amelioration of Desert Soil Productivity by Organic Matter Dressing and Arbuscular Mycorrhi-zal Inoculation

摘要

A field experiment was conducted in desert soil to investigate the effect of chicken manure (2.5 and 5 tons fed_(-1)) on some chemical properties and biological activity of the soil as well as on the growth of maize plants (Zea may L.). The main plots were uninoculated (-AMF) and inoculated with arbuscular mycorrhizal fungi (+AMF). The subtreatments were as follows (1) untreated soil (control); (2) fertilized with NPK; (3) fertilized with 5.0 ton fed_(-1) chicken manure (CM) and (4) fertilized with 1/2 NPK +1/2 CM. Application of CM alone or with NPK markedly increased the amount of organic carbon, total-nitrogen (N), total and available phosphorus (P) in soil. The CM with AMF inoculation improved soil organic matter status and enhnaced the microbiological activity, which in turn led to increases in CO_2 evolution, enzymatic activities (invertase, phosphatase and dehydrogenase). Nevertheless, those values in amended soil with CM alone or with NPK were higher than in fertilized soil with NPK or control soil. This indicates that the improvement of soil biological acitvity has been brought about by the organic amendment. This favorable effect on soil biological activity was more noticeable with the addition of 5 tons fed_(-1) CM than with other treatments. Also, CM induced significant increase in grain yields and their nitrogen and phosphorus contents relative to mineral fertilizer treatments. Percentage of mycorrhizal infection was increased by organic amendment where AMF formation was higher with 5 tons followed by the combined treatment (1/2 NPK + 1/2 CM).