Morphological characterization of soybean (Glycine max L. Merril) in drought stress condition and P fertilizer application

Drought stress in plants can occur due to an imbalance between the availability of water with the water needs of plants. Drought stress can cause morphological changes. This study aims to identify changes in the morphological character of soybean plants in drought stress conditions and P fertilizer application. This research was carried out at the screen house and laboratory of tissue culture of the Faculty of Agriculture, University of Sumatera Utara, Medan. This study uses a Completely Randomized Design (CRD) with 3 treatment factors. The first factor is the variety consists of 2 types, namely Devon 1 and Dering. The second factor is the field capacity of water content which consists of 3 levels, namely 80, 60 and 40% field capacity. The third factor is the application of P fertilizer consists of 5 levels, namely without P application, 1 recommended dosage of Rock phosphate, ½ recommended dosage of Rock phosphate, 1 recommended dosage of TSP and ½ recommended dosage of TSP. The results showed that drought stress treatment significantly reduced total leaf area (18.99%), root length (23.43%), root dry weight (16.67%) and crown dry weight (30.91%) when the available soil water content was reduced from 80% to 40% KL. Application of 1 dose of TSP resulted in the highest increase in root length, root dry weight and shoot dry weight compared to other treatments.