Abstract
Root architecture critically influences plant growth and survival. Pistachio plants face challenges because of the limited lateral roots within a taproot system and the poor survival rates if the primary root tip is severed during transplantation. This study investigated the effects of radicle-tip cutting (RC) on lateral root formation and growth of Pistacia vera L. ‘Ohadi’ seedlings. A factorial experiment with varying radicle lengths (L1-L5) and cutting site portions (CS1-CS5) was conducted. Control plants had an intact radicle tip. Following treatment, seedlings were transferred to 2 L pots filled with perlite, and nourished weekly with half-strength Hoagland's solution. After nine weeks, growth parameters and root characteristics were assessed. Results indicated that optimal radicle-tip cutting occurred at a radicle length of 2–3 cm (L3), with an ideal cutting distance of 3 mm from the radicle-tip (CS3). This treatment (L3CS3) led to improved growth (plant height, leaf area, shoot fresh weight (FW), root FW, shoot dry weight (DW), root DW) and root architecture (number of lateral roots (NLR), network depth (NWDP), network volume (NWVL), network convex area (NWCA) parameters, enhancing plant vitality. These findings offer valuable insights for nurserymen aiming to produce pistachio seedlings with robust lateral roots and higher post-transplantation survival rates.