Effect of planting distance on the root system of peach trees

Root weight and distribution in four-year-old peach trees planted at three spacings, viz. 6 x 6 m, 3 x 3 m and 6 x 1.5 m were assessed. Total root weight per core was the maximum in the 6 x 1.5 m planted trees followed by those at 3 x 3 m and 6 x 6 m distances respectively. The maximum root weight per core was recorded at a distance of 30 cm and the minimum at a distance of 120 cm from the tree trunk. The root weight increased significantly with depth up to 60 cm in all the planting distances. Below 60 cm soil depth, the concentration of roots decreased. But in the trees planted at 3 x 3 m, 24.05% of the total roots were found below 60 cm profile depth. The grades of peach root were also affected significantly by the planting distances. In 6 x 1.5 m planted trees, the maximum root weight per core fell in grade IV (>10 mm diameter) and minimum in grade I (<2 mm diameter) and they constituted 61.32 and 7.46% of the total root weight respectively. In the 3 x 3 m planted trees, grade III (4–10 mm diameter) and grade IV (>10 mm diameter) roots were statistically at par with each other and significantly more than grade I (<2 mm diameter) and grade II (2–4 mm diameter) roots. However, in 6 x 6 m planted trees, grade III (4–10 mm diameter) roots were maximum which accounted for 41.28% of the total root weight, followed by grade I (<2 mm diameter) roots which contributed 28.33% to the total root weight.