تأثير المحراث تحت سطح التربة الاعتيادي و المطور و عمق الحراثة في دليل التفتيت و التوزيع الحجمي لتجمعات التربة

الملخص EN

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 .