Spatial root distribution of apricot trees in different soil tillage practices

Abstract

Root and soil water distribution was studied in a mature drip-irrigated apricot (Prunus armeniaca L. cv. Bu´lida) orchard with different soil tillage practices, in a loamy textured soil with a 7% slope, located in Murcia (SE Spain). Three treatments were applied between tree rows: control (no-tillage), whereby, following the common practice in the area, weeds were cut back to ground level by a blade attached to a tractor; perforated treatment, where the soil surface was mechanically perforated with an adaptedplough; and mini-catchment treatment, consisting of mini-catchments with low banks manually raised perpendicular to the line of emitters. Almost all of the apricot root system was located in the first 0.75 m of soil depth, with 91% in the first 0.50 m. More than 75% of the roots corresponded to thin roots, with a diameter less than 0.2 mm. Both tillage treatments decreased runoff compared with the control treatment, while the mini-catchment treatment showed the highest change in soil water content after rainfall events. The mini-catchment treatment was performed in an attempt to reduce the rainwater running down the slope, leaving the accumulated water near plant roots, an effect which was responsible for the higher root length density (RLD) values found in this treatment. In addition, roots were distributed over a wider area, providing higher RLD values up to 1 m from the emitter, meaning that a higher soil volume was explored. For these reasons, the mini-catchment treatment was seen to be the most beneficial soil tillage treatment for optimising water use in semiarid conditions.

Effect of tillage and water pressure head on the hydraulic properties of a loamy soil surface

“…This led to an increase in infiltration due of the increase in hydraulic conductivity. Thus, soil surface tillage treatments might facilitate infiltration during rainfall events, reducing runoff (Ruiz-Sánchez et al, 2005). Under the present experimental conditions, the flux of water entry into the soil was characterised by the relative dominance of gravity over the capillary forces, independent of the water pressure head imposed.…”

“…It is important to note that the low hydraulic conductivity values measured in the control treatment (Table 2), together with the slope of the orchard (» 7%), could be a cause of notable runoff under non-tilled conditions (Ruiz-Sánchez et al, 2005). Angulo-Jaramillo et al (1997) reported similar hydraulic conductivity in sandy-loam and sandy soils Effect of tillage and pressure head on soil hydraulic properties 183 Table 2).…”

Effects of salinity and nitrogen on cotton growth in arid environment

“…Roots were collected after the soil was passed through a 0.5-mm sieve with the aid of a water jet. Debris, weeds and dead roots were sorted by hand from the 'live' roots during washing, based on visual observation that the 'live' roots appeared light in colors (Oikeh et al 1999;Qu et al 2003;Ruiz et al 2005). Each plant component was washed with distilled water, dried in an oven at 70°C for 72 h, and weighed.…”

Root and aerial growth in early-maturing peach trees under two crop load treatments

“…Root studies under field conditions are labour intensive and the destructive methods involved make repeated measurements at the same site virtually impossible (Böhm, 1979;Ruiz-Sánchez et al, 2005). Recent studies describe the use of ground-penetrating radar (GPR) as a non-invasive means for field root investigations, although the technique is limited to coarse roots (Guo et al, 2013).…”