Pollen embryos were obtained from eight genotypes and viable green plants were regenerated from four genotypes in an anther-culture experiment with 165 genotypes of Phleum pratense L. Formation of proembryos inside the cultured anthers during the first 10-12 days was significantly influenced by genotypes and by the type of nutrient media. Primary embryos developed into multiple secondary embryos before regeneration of plants. Among a total of 62 plants regenerated, only 13 were albinos. Of the green regenerants, 11 were triploid while 35 were hexaploid when DNA-content was measured by flow cytometry. Eight plants with a triploid DNAcontent did possess the triploid chromosome number of 21. Triploid and hexaploid regenerants from two different parents showed simplified isozyme (GPI and PGD) banding patterns relative to that of their parents.Timothy is the main forage grass in areas north of the 62nd parallel for sown and semi-permanent pastures, because of good winter hardiness and high yield (SIMONSEN 1985). Improved dry matter production via breeding has been reported to be promising (SCHJEDLERUP 1982), with efforts being directed towards the development of cultivars with a good general performance and increased persistence (ROGNLI 1987). Breeding of quantitative traits in timothy, however, is generally hampered by the out-crossing and auto-hexaploid nature of the species (JONSSON et al. 1992).During recent decades, haploid formation, through androgenesis from pollen during anther culture, has been reported for a number of different grass species (ANDERSEN et al. 1991). In timothy, NIIZEKI and KATI (1973) have reported callus formation from cultured anthers and we now provide the first evidence for the regeneration of complete plants from pollen.Plant material for experiment I consisted of 51 different breeding clones of timothy {Phleum pratense L.) kindly provided by Danish Plant Breeding, Ltd. For experiment II, 114 seed plants from 19 different varieties of timothy were raised to the 3-4 tillering stage and divided into two ramets each. Plants for both experiments were vernalized at 1-3 °C for 10 weeks. Plants were subsequently re-potted with peat (Finnpeat B2) in 13 mm plastic pots before being grown for flowering under glasshouse conditions with 10-15°C night and 15-25°C day temperature during May to August. Spikes were harvested when they had emerged 3-4 cm above the sheath, from which those with pollen in mid-to late-uninucleate development were selected after squashing a few flowers in carmine acetic acid. These were surface-sterilized by immersing in 70 % ethanol with one drop of tween/litre, followed by 8 min in 3 % Korsolin (GmbH & Co., Hamburg) and rinsing three times with sterile water. For induction of embryos, anthers were cultured on R2M and FW U.S.
The study was carried out, in the laboratory of Plant Virology, Plant Protection Department, College of Agriculture, University of Kerbala, to isolate and identify six isolates of the fungus Cladosporium sphaerospermum isolated from different environments (seeds, air, plant residues, and soil) in Al-Najaf province, Iraq. The fungal isolates were identified using the polymerase chain reaction (PCR) and determining the nucleotide sequence products of DNA using ITS1 and ITS4 primer pair. Results of analysis of the nucleotide sequences using BLAST (Basic Local Alignment Search Tool) showed that all the identified isolates of the fungus belong to C. sphaerospermum. A comparison of the nucleotide sequences with those available in the National Centre for Biotechnology Information (NCBI) revealed that all the identified C. sphaerospermum sequences were previously registered in NCBI.
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