What are the genomic consequences for plastids in a mixotrophic orchid (Epipactis helleborine)?

The chloroplast (plastid) controls carbon uptake, so its DNA sequence and function are highly conserved throughout the land plants. But for those that have alternative carbon supplies, the plastid genome is susceptible to suffer mutations in the photosynthetic genes and overall size reduction. Fully mycoheterotrophic plants receive organic carbon from their fungi partner, do not photosynthesize and also do not exhibit green coloration (or produce substantial quantities of chlorophyll). Epipactis helleborine (L.) Crantz exhibits all trophic modes from autotrophy to full mycoheterotrophy. Albinism is a stable condition in individuals of this species and does not prevent them from producing flowers and fruits. Here we assemble and compare the plastid genome of green and albino individuals. Our results show that there is still strong selective pressure in the plastid genome. Therefore, the few punctual differences among them, to our knowledge, do not affect any normal photosynthetic capability in the albino plant. These findings suggest that mutations or other genetically controlled processes in other genomes, or environmental conditions, are responsible for the phenotype.

Paper chromatography of anthocyanins in two species of Aconitum from the Tatry .Mts.: A. variegatum (L.) Rchb., and A. napellus ssp. skerisorae (Gayer) Seitz.

The results of studies on phenolic compounds occurence and variation in the two Aconitum species were reported in our previous paper (Szweykowski, Krzakowa, 1977a and b). A modified extraction method allowed us to get additional data on anthocyanin variation in flowers of the same species. In addition one albino plant of<i> A. variegatum</i> was also investigated in this respect.

The Role of Drought Stress on Anther Culture of Wheat (Triticum aestivum L.)

Drought stress was found to pose a significant effect on anther culture of wheat, namely Barkat, Kanchan and Pavon-76. Regeneration potentials of these varieties were determined by estimating the percentage of anther response, embryo induction, embryo regeneration and production of green and albino plants. It was observed that out of five treatments such as T1 (1 hr), T2 (3 hr), T3 (5 hr), T4 (7 hr) and T5 (9 hr) only T2 showed highest percentage of embryo yield and green plantlets. The T1 and T3 also gave significantly better results compared to the control. All the genotypes produced embryos and green plantlets and of them Barkat showed best performance followed by Kanchan and Pavon 76. Genotypes, under this study, produced green plants in addition to albinos but T4 and T5 showed three - fourfold higher albino plant production in comparison to treatments. Key words: Anther culture, Drought stress, Haploids, Triticum aestivum D.O.I. 10.3329/ptcb.v20i1.5965 Plant Tissue Cult. & Biotech. 20(1): 55-61, 2010 (June)

Anther culture properties of oat x wild red oat progenies and a search for RAPD markers associated with anther culture ability

A study was carried out to improve anther culture ability of the non-responsive cultivated oat, Avena sativa L. cv. Puhti by introgressing favourable alleles from the responsive wild red oat, Avena sterilis L. acc. CAV 2648. Anther culture ability of these parental lines and F2 progenies of their cross and two backcrosses was tested. Genotype effects were significant on all anther culture traits measured. The number of anther culture derived embryo-like structures was highest in acc. CAV 2648, and the number of green regenerants from the Puhti × CAV 2648 progeny. Anther culture response was greatly reduced in backcross progeny and was least in cv. Puhti. Random amplified polymorphic DNA (RAPD) was used to test for marker associations with oat anther culture traits in a population of 38 F2 progenies. Two RAPD markers were putatively associated with improved production of green regenerants (one derived from acc. CAV 2648 and the other from cv. Puhti). One marker putatively associated with decreased albino plant regeneration (derived from acc. CAV 2648). These markers might be useful for selecting alleles for better anther culture ability among progeny of planned crosses. In addition, three markers, derived from acc. CAV 2648, were putatively associated with decreased anther culture response rates.;