The cytological effects of many herbicides have been studied on different plant materials e.g. Ioxynil on roots of Vicia faba and Pisum sativum (Rost et al. 1977), Fluometuron on roots of wheat and broad bean (El-Sadek and Ashour 1978), Stomp on roots of Allium cepa (Mousa 1982), Glean on roots of Allium cepa and Vicia faba (Badr and Ibrahim 1987), Igran and Garlon-4 on roots of Allium cepa (El-Khodary et al. 1987, 1989). It has been found that all of these herbicides were antimitotic and caused various types of mitotic aberrations such as C-metaphase, polyploid cells, multipolars, bridges and laggards. The use of chromosomal aberrations, induced by pesticides in crop plants, is therefore being accepted as indicators of genetic damage (Ma 1982). Tribunil (N-2-benzothiazolyl-N, N-dimethylurea) is a broad spectrum herbicide. It is also known as methabenzothiazuron.

BackgroundWheat is considered the most important cereal crop all over the world. The wheat weevil Sitophilus granarius is a serious insect pests in much of the wheat growing area worldwide and is responsible for significant loss of yield. Avidin proteins has been proposed to function as plant defense agents against insect pests.ResultsA synthetic avidin gene was introduced into spring wheat (Triticum aestivum L.) cv. Giza 168 using a biolistic bombardment protocol. The presence and expression of the transgene in six selected T0 transgenic wheat lines were confirmed at the molecular level. Accumulation of avidin protein was detected in transgenic plants compared to non-transgenic plants. Avidin transgene was stably integrated, transcribed and translated as indicated by Southern blot, ELISA, and dot blot analyses, with a high level of expression in transgenic wheat seeds. However, no expression was detected in untransformed wheat seeds. Functional integrity of avidin was confirmed by insect bioassay. The results of bioassay using transgenic wheat plants challenged with wheat weevil revealed 100 % mortality of the insects reared on transgenic plants after 21 days.ConclusionTransgenic wheat plants had improved resistance to Sitophilus granarius.

Many cytological studies have been carried out to detect the harmful effect of different pesticides on different plants (Grover and Tyagi 1980, Njagi and Goplan 1981, Mousa 1982, Reddy and Rao 1982, Soriano 1984, Amer and Farah 1985, Amer and Ali 1986, EL-Khodary et al. 1987.The herbicide 3, 5, 6 trichloro-2-pyridinyloxy-acetic acid, is also known as Garlon-4 . The active chemical ingredient in Garlon herbicide is triclopyr.In both the laboratory and the field, triclopyr has demonstrated highly effective control of many woody plants and broad leaf weeds.The present investigation was carried out to study the cytological effect of the herbicide Garlon-4 on the process of mitosis in root tips of Allium cepa. Materials and methodsPure strains of bulbs of Allium cepa (variety Giza-6) were used as plant test material. Roots while intact, were treated with different concentrations of the herbicide, Garlon-4, ranging from 28ppm to 38400ppm for 3, 6, 12 and 24 hours. The beakers containing Gest solutions were agitated after every 30 minutes since the chemical left a settling suspension.Roots were fixed immediately in acetic alcohol (1:3) for 24 hours.Examination of the roots was done in permantent root tip squash preparation stained by the Feulgen technique.Three replicates were preformed for each treatment and the control, and scoring was made from three roots of each replicate. The mitotic index was calculated for each treatment as a number of dividing cells/100cell. The data obtained from the different treatments were statistically analysed. Results and discussionThe herbicide in the present study caused a change in the frequencies of the different stages. Their frequencies depend on the duration of treatement and concentration of the chemical ap plied. The frequency of prophase increased after treating the root tips of Allium cepa with low concentrations.With higher concentrations and long periods of treatement, the frequency of prophase dorpped and an increase in the metaphase frequency was noticed (Table 1). These changes in the stages of mitosis indicate that Garlon affects the relative duration of each stage

Background Fabaceae is considered as the third largest family, which includes more than 727 genera and 20,000 species. The genus Vicia has from 180 to 210 species. Vicia species have a great economical and agricultural importance. Karyotype study of chromosomes and SDS-PAGE for seed storage proteins (soluble and non-soluble proteins) were carried out on five Vicia species (Vicia macrocarpa, Vicia sativa, Vicia narbonensis, Vicia ervilia) collected from IPK, Germany, and Vicia faba from Agriculture Research Centre, Giza, Egypt, to find out the phylogenetic relationships among these species. Result From karyotype of studied Vicia species chromosomes, it was found that V. macrocarpa, V. sativa, and V. faba had six pairs of chromosome (2n = 12) while V. narbonensis and V. ervilia had seven pairs of chromosome (2n = 14). The most related species was found between V. ervilia and V. narbonensis (77.8%) depending on seed soluble protein similarity level, but between V. narbonensis and V. macrocarpa was 70.0% depending on seed non-soluble protein similarity level, while between V. ervilia and V. narbonensis, the most related species was 69.0% depending on collective data of both soluble and non-soluble seed storage protein. Conclusion The phylogenetic relationships between the studied species depending on collective data of protein markers and karyotype characteristic were as follows: V. ervilia is closely related to V. narbonensis, while V. narbonensis is related to V. macrocarpa and V. ervilia, but the degree of relation between V. narbonensis and V. macrocarpa is less than the relation between V. narbonensis and V. ervilia. Equally, while V. sativa is closely related to V. macrocarpa, but V. faba is distant from all other studied species.

SummaryThe chromosomal positions of 5S and 25S rRNA genes, as well as of DAPI (4Ј,6-diamidino-2-phenylindole) bands are described for 5 Vicia species (Vicia macrocarpa, Vicia sativa, Vicia narbonensis, Vicia ervilia and Vicia faba) to find out the phylogenetic relationships among studied species. From the results, it was concluded that the phylogenetic relationships among the studied species are as follows: Vicia ervilia is closely related to Vicia narbonensis and Vicia narbonensis is related to Vicia macrocarpa. However, the degree of relation between Vicia narbonensis, and Vicia macrocarpa is less than the relation between Vicia narbonensis and Vicia ervilia, while Vicia sativa is closely related to Vicia macrocarpa, but Vicia faba is far from all studied species.