JOURNAL OF DEVELOPMENTAL BIOLOGY
Year:2009 | Volume:1 | Issue:4|Papers Count:11

Saintpaulia inonata is a beautiful as well as ornamental plant which is of Generiaceae Species; it is the most important ornamental one among 20 species belonging to Saintpaulia. Saintpaulia inonata is produced for home and in large scales for trading purposes. Saintpaulia Inonata has no seed and is increased utilizing vegetative phase. In this study, leaf and petiole explants have been used in order for much increase by the use of micropropagation techniques. In all done experiments, MS medium has been employed; in MS, BAP hormone treatments of 0, 0.04, 0.08, and 0.12 mgl-1 and NAA of 0, 0.1, 2, 3, and 4 mgl-1 on the basis of latin square table have been applied. The results indicate that in fixed NAA concentrations due to gradual increase of BAP, number of generative leaves in explants samples has a significant growth. It seems that the best induction and the most amount of leaf generation is in 0.08 mgl-1 of BAP and 2 mgl-1 of NAA. In fixed BAP concentration due to gradual increase of NAA concentration, number of generative sprout of leaves has increased but in BAP concentration of 0.12 mgl-1, increase in NAA concentration led to decrease in number of regenerative leaves. In this research, the impact of different concentrations of BAP and NAA on fresh weight and dry weight of regenerative leaves of Saintpaulia Inonata has been examined. Regenerative plants were first in vermicolit and perlite in green house conditions in order to be adapted and then were planted in the soil and were supported to generative phase and then flowering.

In order to study the effects of drought stress on anatomical characteristics in four sunflower cultivars (Azargol, Euroflor, Alstar, Ketil) two separate experiments were carried out. The first experiment was conducted at optimum irrigation whereas the second experiment was considered as drought stress condition.Considering the results of cytohistology in control plants and plants under severe stress showed that drought stress caused decrease in epidermal parenchyma, vascular diameter, length of scelerenchyma cap on phloem and increase numbers of vascular rows and vascular elements in stems. In the leaves of the plants under drought stress, the thickness of lamina and vascular diameter were decreased. In cross sections two layers of palisade parenchyma oa Azargol and Alestar under drought stress reduced to one layer but one layer of palisade parenchyma cells of Euroflor and ketil were denser than those in well irrigated ones. Drought stress caused a decline in vascular diameter, the number of vascular rows and the number of vascular elements. A relative acceleration of embryo development was observed in plant under drought stress except the Euroflor.

The goal of this study is microscopic investigation of unique microstructure in internal structure of birds’ feathers. The investigated samples include pectoral & dorsal feathers selected from the birds belonging to the family of surface feeding ducks (Anas platyr-hynchos), corvidae (Corvus frugilegu), corvus corax, phasinidae (Alectarischukar, partridge, pheasant (Ammoperdix griseogularis, phasianus colchicus) and sterna bergii. After collection from the aforesaid birds, the samples were completely washed by detergent and then dehydration was performed. One-third of middle of barb or one barb was taken from each feather and was sharpen by a sculpel. The obtained samples were fixed on special balls of SEM electronic microscope by liquid glue and then pictures were taken. Each of the magnified pictures was measured. The length of each of the barbiceles located on internal barbules was the ground for our work for explaining the distinction in the performance of feathers of the mentioned birds compared to other birds.

The family Typhaceae L. is aquatic plants that widely distributed throughout the world and is monotypic The genus Typha L. (Typhaceae), comprising 24 species in the world and has the most species diversity in Iran, occur 12 species. Of these: T. latifolia L., T. shuttleworthii W. Koch & Sonder in W. Koch, T. caspica Pobed, T. laxmanniiLepechin., T. azerbaijanensis Hamdi & Assadi, T. angustifolia L., T. domingensis Persl, T. grossheimii Pobed, T. turcomanica Pobed, T. kalatensis Assadi & Hamdi, T. minima Funk in Hoppe, T. lugdunensis Chab. The micromorphological characters of the genus Typha in Iran is discussed. The results obtained confirm the usefulness of leaf surface characters for the identification of most of the species studied as has been traditionally recognized and calyx surface and fruit surface is not variable characters for distance between species. The results of this studies show that our studies SEM ornamentation of leaf can be considered used to separation between species this genus.

Introduction: Vaginal mucus cytology in heifers was determined during different phases of estrus cycle. The aim of this research was to study the alteration in mucosal cytology and percentage of the epithelial cells in external part of uterine cervix during the different stages of estrus cycle in Holstein cows. Material and method: Preparations of vaginal mucus samples were collected from 6 Holstein cows, stained by papsmear technique and then microscopically evaluated. Result: The results showed that the vaginal cytology alterations were associated with the stages of estrus cycle.Conclusion: The results of this study showed that cytological evaluation of vaginal smear can be useful for determination of different phases of estrus cycle. Mucosal epithelial changes are due to the hormonal changes during the estrus cycle. Therefore it can be concluded that vaginal mucus analysis is a useful tool to evaluate the dairy cow reproductive tract physiology.

Self-incompatibility is a widespread mechanism in flowering plants which prevents self-fertilization and promotes out-crossing. In this study, cytochemical staining were carried out on self- and cross-pollinated styles in Petunia hybrida Bravo cool water mix (self-compatible) and P. hybrida Bravo purple star (self-incompatible) cultivars using Toluidine blue, Periodic-acid Schiff`s reagent (for proteins and carbohydrates staining, respectively), Sudan black and Rhodamine B hexyl ester (for lipids staining). The ultrastructure of self- and non-self pollen was also studied in the style tissues of Bravo purple star cultivar by transmission electron microscopy (TEM). Moreover, electrophoresis pattern of proteins was studied using SDS-PAGE method. The content of total protein, phenolic compounds and the activity of polyphenol oxidase (PPO) were studied spectrophotometrically. There was not considerable difference between cytochemical compounds in self- and cross-pollinated styles in both cultivars studied by cytochemical staining. Self-pollination caused to some ultra-structural changes in pollen tube and transmitting tissue of the style of this cultivar. There was a difference between electrophoresis patterns of the styles in two cultivars. Based on our results, it seems that self-pollination affects metabolic processes. These metabolic changes result in ultra-structural abnormalities in the incompatible pollen tubes and consequently self-pollen rejection in the self-incompatible cultivar Bravo purple star.

Background: Hydrocephalus is a condition in which there is an abnormal build-up of cerebrospinal fluid within the ventricles and/or subarachnoid space, which leads to elevated intracranial pressure (ICP). CSF contains growth factors and cytokines secreted from the choroids plexus as well as subcommissural organs which are known as modulators of neurogenesis, differentiation and brain extracellular microenvironment and also show changes associated with neurological disorders and abnormalities of development. VEGF is the prime hypoxia inducible angiogenic factor. We assumed that increased ICP leads to reduced oxygen tension in brain tissue, which triggers VEGF gene transcription.Material and Method: Measurements were performed on CSF and serum aliquots obtained from control (n=16) and hydrocephalic patients (n=14), age- and sex-matched, were collected by lumbar puncture (LP) in the children hospital medical center of Tehran from 2006 to 2008. VEGF and total protein concentrations were determined by enzyme-linked immunosorbent assays (ELISA) and Bradford method, respectively.Results: VEGF and total protein concentrations were significantly elevated in hydrocephalus CSF samples compared with those in controls (p<0.05, p<0.001, respectively). There was only a slight insignificant elevation in serum VEGF concentrations.Conclusion: Under normal conditions there is only diffuse expression of VEGF in the brain, with the exception of some specialized cells of the choroid plexus. In contrast, under local or systemic hypoxia, neurons, astrocytes, and microglial cells all show enhanced VEGF expression. The present study shows that VEGF concentrations are much higher in the CSF of children with hydrocephalus than in control samples and VEGF may be involved in hydrocephalus pathophysiology.

The ongoing way of multiplication in Codiaeum aucobifolium L. is cutting of the leafy stems, which is not completely successful and it could increase the number of infected plants. To proliferation plant tissue technique was used. The explants of leaves and internodes were cultured on 2, 4-D (1 mg/lit) supplemented media including: (Mitra & chaturvedi, Anderson, Murashige & Skoog). The An medium was the best in regard to the production of big and fresh calli. In the other experiment was studied only in An by adding different concentrations of BAP (0, 0.5, 1, 2, and 4 mg/lit) Together various dilutions of one of the auxins including: IAA, 2, 4-D or NAA. Callus induction was greatest in IAA (4 mg/lit)+BAP (1 mg/lit), NAA (2 mg/lit)+BAP (1 mg/lit) and 2, 4-D (1 mg/lit) alone. To evaluate the organogenesis, the greenest cultured Calli were Subcultured in the media supplemented by various concentrations of different cytokinins (2ip, BAP, Kin, and coconut milk) and above auxins. The most excellent organogenesis was achived in coconut milk (20%)+2, 4-D (1 mg/lit). The best combinations for elongation and proliferation of shoots were 2ip (1 mg/lit) + IAA (0.5 mg/lit) and IAA (2 mg/lit) + BAP (1 mg/lit) respectively.