Effects of root pruning to growth and root growth potential of Benguet pine

The country faces the dreaded consequences of its massive, deforested areas. To rehabilitate, restore, and preserve these areas, reforestation projects are needed and one of its essential activities is producing quality seedlings that could survive in harsh conditions. Thus, it is vital to consider a nursery management practice like root pruning that relatively assess nursery seedling quality and performance. The study was carried out to evaluate the effects of root pruning on the growth and root growth potential (RGP) of Benguet pine seedlings which is commonly used in the Cordillera Region, Philippines. The study was laid out following a completely randomized design with 4 treatments replicated 3 times: T0 - Control (not root pruned), T1 - root pruned (5cm from root collar), T2 - root pruned (7cm from root collar), and T3 - root pruned (10cm from root collar). The result showed that in terms of height growth, root pruned seedlings at 5cm from root collar (T1) obtained the highest value with 16.70cm. While relative to root collar diameter, number of lateral roots, root length, root and shoot dry weights, root-shoot ratio, sturdiness quotient, and seedling quality index, not root pruned seedlings relatively showed higher and favorable results with 0.78mm, 44.47, 51.53cm, 11.10g, 32.83g, 0.34, 14.16, 13.33, respectively. With the proper management, care, and maintenance, 100% survival rate has been observed in the study. Statistically, the results showed significant difference on the number of roots, root dry weight, root-shoot ratio, and seedling quality index, while comparable results on the height, root collar diameter, root length, shoot dry weight, and sturdiness quotient. Thus, it is relevant to consider some factors like frequency of root pruning treatment, age of the seedlings, duration of conduct, number of nodules, and soil and water management for seedlings for more reliable assessment of plant quality and performance.