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• Effects of methyl jasmonate, salicylic acid and phenylalanine on aloe emodin and aloin in diploid and tetraploid Aloe barbadensis

  S. Shafighi

  A. Moieni

  S. Rashdi Monfared

  Views:

  253

  Aloe vera is one of the most famous medicinal plants. Aloin and aloe emodin are the most important active compounds in this plant. The purpose of this research was the comparison of aloin and aloe emodin production after the elicitation by methyl jasmonate, salicylic acid, and phenylalanine in diploid and tetraploid Aloe vera plants in greenhouse conditions. The plants were treated with the concentrations of 25, 50, and 100 µM. The amounts of aloin and aloe emodin were determined 24 and 48 hours after application of the treatment. HPLC analysis showed that the leaves of the control diploid plants (without applying elicitors) had more aloin (1.20 fold) and aloe emodin (1.14 fold) than the control tetraploid plants. The maximum concentration of aloin (1.15 ± 0.07 µg mg-1 dry weight) was obtained after the elicitation by 25 µM methyl jasmonate, 24 hours after treatment, in diploid plants) 6.36 fold compared to the control (0.18 µg mg-1 dry weight (. In addition, the maximum concentration of aloe emodin (0.28 µg mg-1 dry weight) was obtained after the elicitation by 25 µM salicylic acid, 24 hours after treatment, in diploid plants) 6.18 fold compared to the control (0.04 µg mg-1 dry weight)). The long-term effect of three studied elicitors (after 240 days) on plant health and survival was also studied. This investigation showed that only methyl jasmonate at a concentration of 100 µM was resulted in the death of Aloe vera plants.

• Self-(in)compatibility in sour cherry (Prunus cerasus L.). A minireview

  117-120.

  A. Hegedűs

  Views:

  185

  Sour cherry (Prunus cerasus L.) is an allotetraploid species derived from hybridisation of the diploid sweet cherry (P avium L.) and the tetraploid ground cherry (P. fruticosa Pall.). Although numerous self-incompatible cultivars exist, the most sour cherry cultivars are self-compatible, which might be due to their tetraploid nature. This review is dedicated to show the limited information on the genetics of self-incompatibility in sour cherry accumulated during the last five years. Two different hypotheses (genomic arrangement of the alleles or the accumulation of non-functional S-haplotypes) are discussed. Heteroallelic sour cherry pollen was shown to be self-incompatible, which is counter to the Solanaceae where heteroallelic pollen frequently self-compatible due to a kind of competitive interaction between the two different alleles. This review highlights some inconsistencies in the hope that clarification will be achieved in the near future.

• Aminoglycoside antibiotics affect the in vitro morphogenic response of chrysanthemum and tobacco

  93-104.

  Da Silva Teixeira

  S. Fukai

  Views:

  119

  Broadly the success of genetic transformation of plants requires non-chimeric selection of transformed tissues and its subsequent regeneration. With rare exceptions, most plant transformation protocols still heavily utilize antibiotics for the selection of transgenic cells containing an antibiotic-degrading selectable marker gene. The morphogenic capacity of in vitro chrysanthemum and tobacco stem and leaf explants change with the addition of aminoglycoside antibiotics (AAs). Of 6 antibiotics tested, phytotoxicity occurred at 10-25 and 50-100 pgml^-I in chrysanthemum and tobacco explants, respectively, depending on the size of the explant and the timing of application. The presence of light or darkness also had a significant effect. The use of transverse thin cell layers (tTCLs) in conjunction with high initial AA selection levels supported the greatest regeneration of transgenic material (adventitious shoots or callus) and the lowest number of escapes. Flow cytometric analyses demonstrate that regeneration can be predicted in both species, depending on the ploidy level of the callus. Endoreduplication was not observed in chrysanthemum, even at high AA levels, but occurred (8C or more) in tobacco callus, even at low AA concentrations (5-10 pgml^-1). The higher the AA level, the greater the DNA degradation and the lower the 2C and 4C values.