Morphology and Cytology of Tissue Culture Derived Octoploid of Elymus canadensis and its Selfed Progeny

Thirty five octoploids (2n = 56). two aneuploids (2n = 54), and one hexaploid (2n = 42) were obtained from the self-fertilized octoploid which was regenerated from the immature inflorescence culture of Elymus canadensis. The octoploid regenerant showed gigas leaves and stems but reduced tillering and fertility. The selfed octoploid progeny varied from genotype to genotype for all of the characters investigated. Hexaploid was morphologically superior to other ploidy levels. Its dry matter yield was 34 % to 40 % higher than the octoploids and the tetraploids but fertility markedly decreased to 7.4 %. Chromosome pairing at metaphase 1 in the octoploid regenerant and its selfed progeny — octoploid, aneupioid. and hexaploid — were 2.57IV +0.83III + 21.23II + 0.971; 3.06IV + 1.06III + 19.66II + 1.251; 2.23IV + 0.85III + 16.54II + 4.69I; and 0.41IV + 8.34III + 8.25II ? 3.141 per microsporocyte, respectively. High frequency of trivalents in hexaploid indicated that it is a doubled triploid. Unequal chromosome disjunction, laggards, and chromatid bridges were commonly observed at the anaphase stage in the first and second meiotic division.