EFFECT OF TILLAGE SYSTEM AND MULCHING ON GROWTH AND YIELD COMPONENTS OF TWO RAPESEED CULTIVARS (Brassica napus L.) UNDER DRY LAND FARMING.

Abstract

The experiment was conducted out at the field of college Agriculture andForestry at two agricultural seasons 2009 – 2010 and 2010 – 2011 in clay loam soil.The aim of the present research is to study the effect of two varieties: RPG902 andBristo, and two tillage systems: minimum tillage (at the depth 8 – 10 cm) using adisk harrow and convential tillage (at the depth 18 – 20 cm) using mold board plow,and three mulching levels: control (without mulching), mulching with 2000 and4000 kg.ha-1 wheat straw, on the growth and yield of rapeseed. The experiment waslaid out as factorial experiment in split – plot design with three replicates. Thetillage system engaged the main – plots, whereas two varieties and mulchingconsidered as sub – plots. The result of two seasons reveled that minimum tillageand mulching with wheat straw showed a greater water retention capacity with lowbulk density and high soil porosity compared with convential tillage and withoutmulching treatments, this led to improved soil structure and plant growth. Thefollowing characters were significant surpass: no. siliqua / plant, 1000 seed wt. ,seed yield and oil percentage affected by RPG902 variety. The previous characterswere also surpass at the minimum tillage except for 1000 seed wt. . using mulchingwith wheat straw led to significant increase in most of characters studied. Thehighest no. Siliqua / plant, seed yield and oil percentage were achieved byinteraction RPG902 variety with minimum tillage for both seasons, whereasinteraction minimum tillage with straw mulching gave a significant increase in theNo. siliqua / plant and seed yield for the first growing season only.