EFFECT OF SEED SIZE AND POD BEARING ZONE ON SEED YIELD AND SEED QUALITY IN FABA BEAN (Vicia faba L.)VARIETIES AT HARAMAYA, EASTERN ETHIOPIA

Abstract

The influence of variety and seed size on faba bean seed quality, crop phenology, seed yield and seed yield components in the first experiment, and the effect of these two factors and pod bearing zone (PBZ) on seed quality attributes in the second experiment were studied. The interaction between varieties and seed size had significant influence on speed of germination (SG), seedling dry weight (SDW), number of seeds per POD (SPP), seedling root length (RL), seedling shoot length (SL), seed vigor index-I (SVI-I), seed vigor index-II (SVI-II), and electrical conductivity (EC). In all, large seed by variety interaction showed the higher performance compared with interactions between all other levels of variety and seed size. The discrete effect of variety and seed size were significant on G, RL, SDW, SVI-II, SG and seed germination (AgG). Seed quality attributes preceded with ‘Ag’ are findings of tests under induced-stress conditions. The higher the seed quality attributes under induced-stress conditions, the longer would be storability. Variety also had significant effect on SVI-I, field emergence (FE), number of pods per pod (PPP), SPP and seed yield (SY). Large seeds had high SDW, SVI-II, SVI-I and low EC. The maximum SG, RL, SL, soot length (AgSL) and seed vigor index-I (AgSVI-I) were also observed in medium and large seeds. In addition, seed size had influence on FE and PPP. The interaction of variety, seed size and PBZ showed significant effect on SL, SVI-I, SG, AgSL, root length (AgRL)and AgSVI-I. In general, interaction of large seed, bottom PBZ and variety showed the higher performance in seed quality attributes. The interactions between seed size and PBZ were significant on AgG, AgSL, AgRL and AgSV-I. The large seeds of bottom PBZ had maximum observation in SG, AgSL, AgRL and AgSV-I. Bottom and middle PBZs had nearly equal influence on SDW and SVI-II. Significant correlation was observed between SDW and G, RL,SG, SVI-II, AgG, FE, SPP; SVI-II and AgG, RL; AgG and AgRL, AgSVI-I; AgSL and AgRL; AgRL and AgSVI-I. FE and SL, SG, SVI-II, SVI-I, SY; SPP and SY; and significantly negative correlation between SVI-I and PH. In conclusion, varieties, seed size and PBZ revealed differential effect on faba bean seed quality, phenology and SY. PBZ had less significance on seed quality attributes compared with variety and seed size. Thus, variety and large seed size are indispensable for subsequent growth and development of faba bean. SDW, SG and SVI-II are reliable seed quality test procedures under non-stress conditions. Induced stress test was stringent to identify seed quality differences in seed lots specifically for SL and SVI-I