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Chromosome doubling of microspore‐derived plantlets and calli is a critical step in haploid breeding programs. For anther culture experiments, colchicine, (S)‐N‐(5,6,7,9‐tetrahydro‐l,2,3,10‐tetramethoxy‐9‐oxobenzo[a]heptalen‐7‐yl)acetamide, is the most commonly used compound in doubling the chromosomes of seedlings derived from such experiments. Colchicine, however, is carcinogenic and expensive. We evaluated three antimitotic agents (colchicine; trifluralin, 2,6‐dinitro‐N,N‐dipropyl‐4‐(trifluoromethyl)benzenamine; and oryzalin, 4‐(dipropylamino)‐3,5‐dinitrobenzenesulfonamide) at two treatment durations (48 and 72 h) and two concentrations [colchicine at 0.0125% (313 μM) and 0.025% (626 μM), and both trifluralin and oryzalin at 5 and 10 μM each for their effects on the production of double haploids from anther‐derived calli of two wheat [Triticum aestivum (L.) em. Thell.] cultivars, Pavon and Kitt. Calli from Pavon were more responsive to the three agents than those from Kitt. Colchicine was the most effective in double the chromosome number. for Pavon, 89% of the plantlets from calli treated with colchicine were double haploids (2n = 6x = 42). However, treating calli for 72 h with colchicine at either concentration had a deleterious effect. No significant differences were observed between concentrations of any of the antimitotic agents. All the plantlets produced from the control treatment (without antimitotic agents) were polyhaploids (2n = 3x = 21). These results indicated that colchicine is still the most ffective compound for chromosome doubling, and colchicine treatment of anther‐derived calli is an effective method of obtaining a high frequency of double haploid plantlets through anther culture systems.

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Abstraet t-lomozygous doubled-haploid plantlets derived from anther eulture of wheat {Triticum aestivum L.) and triticale (X Tritieoseeale Wittmack) nre usetui breeding materials. However, effieiency of androgenesis needs improvement. We used media (basic components are the same as 85Df2) each eontaining one of the seven auxins [2,4,5-triehlorophenoxyacetie acid (2,4,5-T), f-chloroptienoxyaeetic acid (pGPA), 3,6-dichtoro-o-anisic aeid (dicamba), 4-aiiiino-3,5,6-trichloropicolinic acid (picloram), indolc-3-hutrytie acid (tBA), iiido!e-3-acetie aeid (lAA), and 2,4-dichtorophenoxyacetie aeid (2,4-D) as a control] m combination with 6-furfurylaminopurine (kinetin). In addition, each of the four cytokinins [6-benzylaininopurine (6-BA), 2-isopentylnyt adenine (2-ip), 6-(4-hydroxy-3-methytbiit-2-enylamino) purine (zeatin), and kinetin as a control] was tested in eombination with t-naphthatene acetic acid (NAA). Anthers containing microspores at inid-uninucteate stage from five wheat cuttivars (Angus, Genturk, Ghris, Kitt, and Pavon 76) and two oetoptoid tritieate lines (T8t, T82) were tested mainly for eatlus induction and polyhaploid production on eaeh of the 11 media. The cultivar X medium interaction was not significant. When averaged over all growth regulators, Pavon was the best cultivar which produeed 14.4 % ealli and 23 % polyhaploid plantlets. Averaged over alt cultivars, the medium containing 2,4-D produced the highest ealli (t3.9 %). Undifferentiated ealli were regenerated on S7T1 medium, which contained lAA (1 mg/1) and kinetin (2 mg/1).

Effects of incubation temperature and developmental stage of microspores on polyhaploid production in three wheat cultivars 'Pavon 76', 'Kitt', and 'Chris' and one tnticale cultivar, 'T8r, were studied using a one-step medmm. Calh failing to differentiate on the one-step medium were placed on a medium containing 1 mg/1 indole-3-acetic acid (IAA) and 2 mg/I 6-furfurylaminopurine (KIN). Anthers containing either early-or late-uninucleate microspores were incubated in dark at 26, 28 or 32 °C for 3 days prior to transfer to 26 °C. Averaged over temperatures and microspore stages, frequency of calli and green plantiets were 8.9 % and 3.4 %, respectively, for wheat cultivar 'Pavon 76', 8.4% and 1.6% for cultivar 'Kitt', 4.5 % and 0.25 % for cultivar 'Chris', and 2.9 % and 0.12 % for the triticale cultivar 'T8r. However, cultivar-by-developmentalstage interaction was significant for frequency of callus induction. Temperature had no significant effects on callus induction and plantlet regeneration. Anthers containing early-uninucleate microspores produced no polyhaploids. Key words: Triticum aestivum -anther cultureculture conditions -temperature response -stage of microspores. Contribution No. 89-283-J from the Kansas Agricultural Experiment Station; Kansas State University, Manhattan.Among the conditions and variables used in an anther culture system, incubation temperature and stage of microspore development are important factors. Since wheat requires cool conditions for germination and initial growth, early research on anther culture generally was carried out at relatively low temperatures (20 to 27 °C) (OuYANG et al. 1973). Culture temperature for inducing microspore callus in wheat ranges from 26 to 30 °G, but 28 to 30 °C was reported best for most cultivars (OUYANG et al. 1983). The responses of anther culture to culture temperature were also affected by growth conditions of anther-donor plants; highest yield of green pollen piantlets appeared at a culture temperature of 30 ^G when the anther-donor plants had been grown in the greenhouse, but was at 32 °G when the donor plants were grown in field (OUYANG 1986, OUYANG et al. 1987. Two wheat cultivars produced 40 % more microspore calli and green plantiets at 30 than at 25 °C (HUANG 1987). High yields of wheat pollen calli and piantlets were obtained at 2% to 32 °G for the cultivar 'Ghris' (Ho et al. 1978). For spring wheat, callus yield was increased when anthers were incubated at 32 °C for 6 days prior to incubation at 26 °G (LI et al. 1988). Variation in intensity and duration of low-temperature U.S. Copyright Clearance Center Code Statement: 0 1 79-954 1 /90/0504-0332$02.50/0

Helicobacter pylori is the causative agent of most cases of gastritis. There is no established gold standard for the diagnosis of H. pylori infection. A reliable diagnosis is crucial to confirm that eradication therapy has been successful. Eighty gastric biopsy and blood samples were obtained from fasting Jordanian patients with Esophago-Gastro-Doudenoscopy (EGD). Several diagnosis tests for H. pylori infections were used and compared including: Culture, microscopic examination, histopathology, Rapid Urease Test (RUT), serology, biochemical tests, antibiotic susceptibility test and molecular method. Forty two patients were considered H. pylori positive in both histopathology examination and RUT test. On the other hand, 57 patient were detected to have anti-IgA, IgG H. pylori antibody positive by ELISA test. Ten patients had equivocal results but not in both tests. A total of 19 biopsy samples were positive for H. pylori according to culture test. This result was confirmed by endoscopic examination, urease, catalase and oxidase. A high percentages of resistance to vancomycin, polymyxin B and amoxicillin was observed (100, 100 and 94.7%, respectively) with various degree of sensitivity to all of the first line of antibiotics. Molecular technique (PCR) was used to detect CagA gene which appeared positive in 14 patients. We conclude that the histopathology and RUT tests are reliable invasive diagnosis for H. pylori. However, culture test appear to be the most important (if the therapy failed) to detect antibiotic susceptibility to H. pylori strains.

Abstract. The honeybee (Apis mellifera L.) has a large number of geographic subspecies distributed across Europe, Africa and Asia, many of which have been described. This identification is important for bee breeding and preserving honeybee biodiversity. To investigate the origin of Jordanian honeybees, 32 samples collected from different locations in Jordan were analyzed using four different enzyme systems: Bg/II site in cytochrome oxidase b (Cytb), EcoRI site in large ribosomal (lsRNA) subunit, XbaI site in cytochrome c oxidase I (COI) subunit and HinCII site in cytochrome c oxidase I (COI) subunit. The first three enzymes were found to be polymorphic. The DNA banding pattern analyses revealed that Jordanian honeybees belong to the East Mediterranean and Middle Eastern mitochondrial lineages.