Growth and yield component analysis of durum wheat as an index of selection to terminal moisture stress. (363)

Authors

  • B. Simane Department of Plant Science, Alemaya University of Agriculture, P.O. Box 138, Dire Dawa, Ethiopia
  • P.C. Struik Department of Agronomy, Wageningen Agricultural University, Haarweg 333, 6709 RZ Wageningen, The Netherlands
  • R. Rabbinge Department of Theoretical Production Ecology, P.O. Box 430, Bornsesteeg 65, 6700 AK Wageningen, The Netherlands

Keywords:

Durum wheat, Drought susceptibility index, Path-coefficient, Relative growth rate

Abstract

Durum wheat (Triticum turgidum L.) yields in Ethiopia are primarily limited by water deficiency. Field and greenhouse studies were conducted using five cultivars (Tob-2, DZ, Boohai, Omrabi-5, and Po) under moisture stress during the terminal period of growth and non-stress conditions to evaluate growth and some components of yield. Analysis of the relative growth rate (RGR) and its components showed significant differences between varieties. Drought-tolerant cultivars had a high RGR during favourable periods of the growing season and a low RGR during moisture stress. Path-coefficient analysis revealed that longer vegetative periods were associated with reduced grain-filling periods (GFP) and negatively associated with drought resistance. The direct effect of number of spikes m-2 (Sm-2) on grain yield (GY) was positive and significant. However, the indirect effect via kernels per spike (K/S) and kernel weight (KW) was negative. Grain-filling period had a strong influence on GY via KW. Kernels per spike had the largest direct effect on GY. Variation in drought susceptibility index among cultivars was significant. This study concluded that lower RGR, longer GFP, increased number of K/S, and limited Sm-2 can be used as selection criteria under water-limited environments for drought resistance.

Issue

Section

Research Papers