Study on root density of Picual and Manzanillo olive trees root system at different soil types

Abstract

The present study was conducted on two olive cultivars trees grown in two different soil types at Suez governorate and Katatba area. The variation in fibrous root distribution, density of soil was determined by intensively sampling four years old Picual and Manzanillo trees (planted originally as cutting) and grown at the two locations during 1994 – 1995. Three trees of each cultivar were sampled. Root samples were collected using an auger 8.5 cm in diameter to a depth of 120 cm (in 30 cm increments) ­ from the four different directions of each tree. Fibrous root samples were placed in plastic bags, transported to the laboratory, washed and then root length measured later, fibrous roots were transferred to paper bags and oven dried at 70 C for 48 hr and then weighed. Fibrous root data of the olive cultivars at different soil depths were used to calculate means for root density (root dry weight mg/cm³ soil), root distribution as a percentage of total weight. Main conclusions could be summarized as follows: 1. Fibrous root density (Dry wt. mg/cm³ Soil) of olive trees was significantly affected by cultivar and soil type. 2. Fibrous root density ranged from 2.5 mg/cm³ to less than 0.02 mg/cm³. Mean fibrous root density generally decreased as sampling depth increased, and as the distance from the tree trunk increased, while, the direction had no effect on the fibrous root density.