Estimation of Heterosis for Seedling Growth Traits in Gum Arabic Acacia senegal [L.] Wild

Aiming at estimating heterosis and identifying superior Acacia senegal hybrids, six provenances were selected based on their divergence in gum zinc and manganese concentration and were crossed using in 6 x 6 half diallel mating scheme to produce 15 F₁ hybrids. The experiment was conducted in the nursery in Gashua in 2014 and 2015 in a Randomized Complete Block Design (RCBD) replicated three times. Percentage mid-provenance and better- provenance heterosis was estimated for seedling growth traits. Molai x Gajiram1 revealed maximum negative mid-provenance (-71.04%) and better- provenance (-77.17%) heterosis for days to emergence and desirable positive better-provenance heterosis (22.62%) for canopy diameter. Also Gajiram1 x Molai showed maximum positive mid-provenance heterosis (125.11%) for number of primary branches while Kukareta x Molai had maximum positive better-provenance heterosis (88.27%) for the trait. Damaturu x Molai exhibited highest positive heterosis over mid-provenance (65.15%) and better-provenance (47.30%) for bark thickness. No significant positive heterosis was observed for seedling height, stem height at first branching and stem diameter at both levels. The hybrids Gajiram1 x Molai, Kukareta x Molai and Damaturu x Molai could be used for future breeding program.