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Callus Induction (callus + induction)
Selected AbstractsEvaluation of tissue culture response from mature seeds of Panicum spp.GRASSLAND SCIENCE, Issue 3 2008Mi-Suk Seo Abstract The genus Panicum contains important warm-season forage grasses and species with potential as biomass crops. We selected Panicum genotypes with high response to tissue culture for genetic improvement. The highest frequency of callus induction from mature seed of Panicum maximum cultivar Natsukaze was obtained on MS medium containing 4.0 mg L,1 2,4-dichlorophenoxyacetic acid and solidified with 0.3% Gelrite. We compared germination frequencies and callus induction capacities among 24 genotypes of 11 Panicum species on this medium. Callus induction frequencies varied among genotypes. Those with high germination frequencies generally had high callus induction frequencies. On the other hand, especially in P. maximum, the callus induction ratio (callus induction frequency/germination frequency) depended on the reproductive mode and ploidy. The callus induction ratio of three sexual accessions of P. maximum were very low compared to apomictic accessions, and besides, a tetraploid sexual accession Noh PL1 had very low germination and callus induction frequencies. Callus induction and regeneration capacities were independent of each other. For shoot regeneration, we transferred callus derived from the 24 genotypes onto MS medium supplemented with 1.0 mg L,1 kinetin and 0.4% Gelrite. Six of the genotypes regenerated plantlets. Among them, Panicum meyerianum produced the highest shoot regeneration frequency of 61.6% and the maximum number of shoots callus,1 in the shortest time. The callus of P. meyerianum also showed vigorous proliferation. We thus selected high-response genotypes of P. meyerianum. [source] The effect of genotype and culture medium on somatic embryogenesis and plant regeneration from mature embryos of fourteen apomictic cultivars of buffel grass (Cenchrus ciliaris L.)GRASS & FORAGE SCIENCE, Issue 1 2006E. L. Colomba Abstract Buffel grass (Cenchrus ciliaris L.) is an important apomictic grass used as forage for ruminant livestock. Biotechnological methods provide opportunities for producing new germplasm. Mature embryos of fourteen buffel grass apomictic cultivars (2n = 4x = 36) were used to induce embryogenic callus formation using a basal medium supplemented with 3% sucrose and with the testing of five concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and four concentrations of 6-benzylaminopurine (BAP). The effects of cultivar and culture medium on callus induction and plant regeneration were evaluated. Significant differences were observed among the fourteen cultivars and the five concentrations of 2,4-D (P < 0·01). Values for embryogenic callus production varied from 0 to 86·7. Most cultivars showed the highest level of embryogenic callus production on the medium with the concentration of 3 mg L,1 2,4-D. The addition of different BAP concentrations in combination with 2,4-D in the medium inhibited embryogenic callus growth and did not permit plant regeneration. The data clearly demonstrated that the genotype and concentrations of 2,4-D had significant effects both on the frequency of embryonic callus formation from mature embryos and on the subsequent efficiency of plant regeneration of apomictic cultivars of buffel grass. Cultivars Biloela and Nunbank showed the greatest efficiency in in vitro culture response. [source] Evaluation of tissue culture response from mature seeds of Panicum spp.GRASSLAND SCIENCE, Issue 3 2008Mi-Suk Seo Abstract The genus Panicum contains important warm-season forage grasses and species with potential as biomass crops. We selected Panicum genotypes with high response to tissue culture for genetic improvement. The highest frequency of callus induction from mature seed of Panicum maximum cultivar Natsukaze was obtained on MS medium containing 4.0 mg L,1 2,4-dichlorophenoxyacetic acid and solidified with 0.3% Gelrite. We compared germination frequencies and callus induction capacities among 24 genotypes of 11 Panicum species on this medium. Callus induction frequencies varied among genotypes. Those with high germination frequencies generally had high callus induction frequencies. On the other hand, especially in P. maximum, the callus induction ratio (callus induction frequency/germination frequency) depended on the reproductive mode and ploidy. The callus induction ratio of three sexual accessions of P. maximum were very low compared to apomictic accessions, and besides, a tetraploid sexual accession Noh PL1 had very low germination and callus induction frequencies. Callus induction and regeneration capacities were independent of each other. For shoot regeneration, we transferred callus derived from the 24 genotypes onto MS medium supplemented with 1.0 mg L,1 kinetin and 0.4% Gelrite. Six of the genotypes regenerated plantlets. Among them, Panicum meyerianum produced the highest shoot regeneration frequency of 61.6% and the maximum number of shoots callus,1 in the shortest time. The callus of P. meyerianum also showed vigorous proliferation. We thus selected high-response genotypes of P. meyerianum. [source] Plant regeneration through callus initiation from mature embryo of TriticumPLANT BREEDING, Issue 1 2007R. M. Bi Abstract The behaviour of diverse Triticum genotypes in the tissue culture response of mature embryo callus was compared, and factors affecting tissue culture response were studied in this paper. Significant differences were detected in callus induction, embryogenic callus differentiation, plantlet regeneration and culture efficiency when mature embryos of 31 plants of different Triticum species were compared. These were the main wheat cultivars of the Chinese northern winter-type wheat region and breeding lines (Triticum aestivum L.), durum wheat (Triticum durum Desf.), cultivable emmer wheat (Triticumdicoccum Schuble) and the common wheat progenitors Triticum dicoccoides and Triticum aegilopides. The genotype dependency was particularly high in tissue culture of mature embryos of these Triticum genotypes. The efficiency of induction, differentiation and regeneration of mature embryos callus was high in genotypes selected out. Mature embryo-derived callus of HB341, TS021, SN2618, T. dicoccum, HB188, and T9817 showed better tissue culture response than the other genotypes. Plantlets can be regenerated from mature embryo-derived callus of 31 genotypes, saving on growth facility resources and time required for the collection of other explants, and providing a solid basis for the genetic transformation and molecular plant breeding of Triticum plants. [source] In vitro chromosome doubling of Miscanthus sinensisPLANT BREEDING, Issue 5 2002K. K. Petersen Abstract The aim was to develop an efficient chromosome doubling method for Miscanthus sinensis to enable the production of triploids and so avoid seed dispersal to the environment. Antimitotic treatments with colchicine or oryzalin were tested in M. sinensis cl. MS-88-110 on: (1) in vitro shoots and plants established in soil; (2) during propagation of embryogenic callus; and (c) during the initial stages of callus induction. All systems produced chromosome-doubled plants. A higher percentage of tetraploids was found after antimitotic treatment at the explant or callus level compared with treatment of in vitro shoots or plants established in soil. In general, oryzalin was more toxic to plant material than colchicine. A higher frequency of chimeras was found among plants with altered ploidy level when the target was formed shoot buds compared with adventitious shoot formation from callus. Antimitotic treatment of embryogenic callus from shoot apices also resulted in a high degree of albinism. [source] |