Comparative study of poplar yield of different cultivars as influenced by irrigation interval in Karaj

Abstract

Poplars are associated with variations in the yield which are influenced by their variable requirements. Due to restrictions in water availability across the country as caused by long-lasting drought periods, the amount and duration of irrigation has been continuously changed. Thus, the qualitative and quantitative growth properties of poplar cultivars is necessary be quantified in association with different irrigation regimes. Furthermore, seedlings and mature trees have different requirements. Therefore, we carried out a survey in Karaj to study 9 species of selected cultivars in a split plot design with 3 replications which we treated with two 4-day and 8-day irrigation regimes. For each treatment, the incoming water were measured by installing WSC flume type 3 which was used to determine section levels and timing of water through the flume by using standard curves for each flume. Data analysis resulted in significant differences observed amongst diameter growth of the clones. However, height volume growth did not show any significant difference between two treatments. The 4-day treatment spent 4500 m3 year-1 water more than the 8-day treatment. The P.e.561/41 clones were strongly affected by varying amounts of water, and the volume of produced wood from 4-day treatment was substantially higher than that of 8-day treatment. The P.e.561/41, P.e.vernirubensis, P.n.62/154 and P.n.betulifolia clones were concluded to excess other investigated clones in volume, diameter and height growth.

Keywords

• Irrigation
• poplar
• Clone