Pomza uygulamalı pamuk ekim tekniği

61 SUMMARY The aim of this research is to determine the possibilities of pumice application in avoiding adverse effects of soil crust in cotton production.Trial were made by covering in top of the seeds with pumice instead of soil. A fertilizer -hopper was attached on to sowing machines for the purpose of pumice flow.Seeding performances of the sowing machines and the pumice flow rates were determined by the laboratory experiments.At the field experiments, two different sowing machines were used for sowing with and without pumice application. Throughout the trials; -Precision drilling machine with perforated rubber seedbelt (Stanhay) and -Cotton planting machine with perforated plate (John Deere) were used. During the laboratory experiments for the determination of the performance of planting machines and amount of pumice flows, the most suitable adjustment of the planting machines were also determined. Field experiments were carried out on the plots which were prepared by classic seedbedpreparation method and Nazilli-84 delinted cotton seed variety was used. Random blocks experimental desing were used in preparing the plots, sowing with and without pumice application were done by four repetitions by two different kinds of planting machines. After sowing, crust was formed on the soil surface by simulated rainfalLFollowing this, the crust formed on the without pumice plots were destroyed by a crust braeker implement.No crust breaking operation was carried out on plots with pumice application. The percentage of field emergence, the average emergence time, the real leaves values and the time62 of real leaves values relating to each variant were calculated by monitoring the emerged seedlings daily. Research results can be summarized as follows: -The percentage of field emergence was higher on the variant of seeding with pumice application. -The average emergence time was shorter on the seeding with pumice application. -The sowing method with pumice application was more successful in terms of the real leaves values. -The time of real leaves values shortened on the seeding rows by pumice application.