Effect of the conventional and modified subsoilers and operating depth on pulverization index and volume distribution for soil aggregate

Abstract

A filed experiment was conducted at agriculture college research station, Garmit Ali , Basrah university in ( 2014 ) . The soil texture is clay . Three plow types were used namely modifiled subsoiler , conventional subsoiler and moldboard plow . The first two plows (subsoilers) were used at operating depths of 30 , 40 and 50 cm . The moldboard plow was used at operating depth of 25 cm . The following abbreviations were used for the modified and conventional subsoilers operating depths 30 , 40 , and 50 cm , which are they S1D1 , S1D2 , S1D3, S2D1 , S2D2 and S2D3 respectively . For the moldboard plow depth of 25 cm MT was used . The experiments were conducted using R.C.B.D. design for three replicates . The treatment S1D3 surpassed the other treatments in giving lower soil pulverization index (Pu.I.) , while MT gave the second lower Pu.I. and S2D3 gave the thired lower Pu.I. The highest Pu.I. was recorded for S2D1 . Aggregate size of 2.8 mm dominated the other aggregate sizes while the lowest percentage of sizes was recorded for 45-50 cm . S1D3 treatment significantly surpassed the other treatments in giving the highest percentage of aggregate lower than 2.8 mm .