Eurasian Journal of Soil Science

Yazarlar: Abdolrahman Barzegar, Abdolamir Yousefi, Nazanin Zargoosh

Konular:Fen

DOI:10.18393/ejss.2016.2.139-145

Anahtar Kelimeler:Water stress,Compaction,Water use efficiency,Clover growth,Nutrient concentration

Özet: Soil compaction and insufficient water supply generally decrease crop performance. The effects of varying compaction and water availability levels on the growth of Berseem or Egyptian clover (Trifolium alexandrimum L.), water use efficiency and nutrient concentration were investigated under greenhouse conditions. Treatments consisted of three soil compaction levels (bulk density of 1.2, 1.4 and 1.6 Mg m-3), and four water availability treatments (40%, 60%, 80% and 100% of soil field capacity) in a factorial combination. Soil compaction had a significant effect on water use efficiency with the highest (0.32 g l-1) at bulk density of 1.4 Mg m-3 and the lowest at the other bulk densities. Soil compaction had no significant effects on leaf area, shoot, root and total dry masses. Water stress resulted in lower leaf area (from 231 to 153 mm2 pot-1), and the stem lengths were 7.6 cm and 4.3 cm for 80% and 60% of field capacity, respectively. Likewise, the highest (0.47 g pot-1) and lowest (0.33 g pot-1) total dry masses were observed at 80% and 60% field capacities. Water use efficiencies were 0.32 and 0.20 g l-1 for 100% and 60% field capacities, respectively. The accumulation of N, P and K per unit length of roots increased with soil compaction. As the water supply increased, the root and shoot dry weight and water use efficiency increased. Treatment of 100% field capacity resulted in the highest accumulation of N, P and K. Results indicated that the treatment of 80% field capacity and bulk density of 1.4 Mg m-3 provided the best conditions for clover performance, among the applied treatments. This study suggests that sufficient water supply can moderate the adverse effects of soil compaction on clover performance.

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