فصلنامه زیست شناسی گیاهی ایران
سال دهم شماره 1 (پیاپی 35، بهار 1397)

Mazafati cultivar of date palm (Phoenix dactylifera L.) is one of the most important cultivars cultivated in Kerman province particularly in Bam. Studies of floral ontogenesis are key elements for understanding sex determination and its control, evolutionary relationships within the palm family and with respect to other monocot groups, as well as in angiosperms as a whole. Development of generative structures was studied using cyto-histological methods. Flowering behavior within single shoots is Pleonanthy in which flowering branches appear in leaves axils and continue to be produced as the palm continues its extension. Initial developmental stages occur while spathes are hided in leaf axil. Female spathes are smaller and have brighter flowers compared to male ones. Flowers contain three sepals and three petals that are distinguishable in shape. In staminate flowers, a rudimentary gynoecium and in pistillate flowers, a sterile androecium was observed suggesting a possible evolutionary movement from an ancestral hermaphrodite flower to the situation of unisexuality and dioecy. Secretary tapetum is degenerated during pollen differentiation. Middle layer degeneration occurs after pollen formation and during its development, thus, somewhat later compared to polygonum type. Phenolic idioplasts are observed in anther parachyma especially in connective location. Their size and number increase during maturation, extended to dehiscence place. Pollen grains are prolate, spindle shape and monocolpate. The gynocium is tricarpellate and apocarpous that only one carpel develops and the rudiments of other two may be observed with fruit. Anatropous ovule contains two integuments, sclereids and idioplasts containing calcium oxalates crystals (raphids) and phenolic compounds.

In this research, apical shoots of Achillea wilhelmsii and A. millefolium at three different developmental stages including thevegetative, flowering and fruiting stages from natural habitat, Martyrs Valley, in West Azerbaijan were collected. Essential oil samples were extracted by water - distillation method (Clevenger apparatus) and were analyzed by GC and GC/MS. The results showed that at different harvest times, in addition to yield, quality and quantity of essential oils were also reported to differ. Of the total compounds identified in the essential oil of A. wilhelmsii, 36 and 16 constituents belonged to monoterpenes (69.23 percent) and sesquiterpens (30.76 percent), respectively. So monoterpenes had the highest share in compounds. In the essential oil of A. millefolium, 37 compounds identified as monoterpene (56.92%) and 28 compounds (43.07%) as the sesquiterpene. The most important compounds in the essential oil of A. millefolium, were 1-8 cineole, camphene, borneol and camphor that 1-8 cineole, camphene & borneol and camphor in May, June and July had the highest value, respectively. Among the major constituents of the essential oil of A. wilhelmsii, compounds camphor, camphene, 1-8 cineol, borneol, 3,5 heptadien 2 ol, 2,6 dimethyl and α-pinene were the highest in the vegetative stage. 1-8 cineole, borneol, myrtanol and thujone were the highest in the fruiting stage. α- linalool, ocimenol, borneol, myrtanol and camphor were the highest in the flowering stage. The results showed that quality and quantity of the essential oils vary in different species and phenological stages. As a result, they havedifferent pharmaceutical actions

In order to investigate the effect of planting date and Mycorrhiza fungi on the physiological, growth characteristics and yield of three cultivars of potato tuber, the treatments were planting date as the main plot at three levels (May 15th, June 1st and June 15th) and the consisted of a factorial combination of three potato cultivars (Agria, Santhe and Arinda) and two levels with and without mycorrhiza as subplots. The results showed that the highest yield of potato tuber cultivars achieved with Arinda in the early cultivating date (May 15th) (38 t ha-1). It was determined that the planting date of May 20th due to the interaction of stages of plant growth (especially flowering) with the maximum temperature of the region was affected by environmental stresses that had a negative effect on the physiological characteristics associated with the photosynthetic pigments. As a result, decreased potato tuber yield in Fereydoun Shahr area. Mycorrhiza has a positive effect on root development, improves the pigments and increases the dry weight of the roots, leaves and shoots. It seems that Agria have less tolerance to environmental stresses due to less production of non-enzymatic (carotenoid) and enzymatic (catalase, peroxidase and ascorbate peroxidase) anti-oxidant, resulting in lower tuber yield in all three planting dates in presence or absence of mycorrhiza.

Canola (Brassica napus L.) is known as one of the most important oil-producing plants worldwide that has a high food value. Today, expansion of planting area of this plant has been highly considered. The presence of weeds in canola fields causes a significant loss in crop yield and quality. So far, the most widely herbicide used to manage weeds is the broad spectrum glyphosate that targets 5 enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme. In this study, with the aim of identification of new strategies to develop herbicides-resistant plants, Glyphosate Oxidoreductase (gox) and epsps genes under the control of CaMV 35S promoter were transferred to canola seedlings with pBI121 expression vector, to develop new plants with higher herbicide resistance level. Acquired seedlings were screened and then subjected to herbicide resistance bioassay. Molecular analysis of transgenic lines through PCR and RT-PCR showed successful integration and expression of the transgene, respectively. Result showed the higher relative resistance of the transgenic lines expressing two gene cassettes compared to single gene cassette lines. This study suggests that simultaneous application of two different strategies can lead to more glyphosate-resistance to develop new genetically modified crops specifically in oilseed plants such as canola.

In this study, callus formation of Salvia leriifolia Benth by stem and leaf explants in the combination of NAA and 2,4-D with Kin and the effect of salicylic acid and methyl jasmonate elicitors (50, 100, 150 mM) in callus on some secondary metabolites were studied. NAA in combination with Kin had no callus production in both of stem and leaf explants, while the most appropriate callus produced by leaf explant at a concentration of 1 mg/L Kin with 2 mg/L 2,4-D. The highest fresh and dry weight, total phenol and flavonoids content were observed in calluses treated with 100 μM of methylisammonate, however, with increasing salicylic acid concentration, fresh and dry weight, total phenol content, flavonoids, rosmarinic acid increased, and the highest content of rusamicin acid and caffeic acid was observed in calluses treated with 100 and 150 μM salicylic acid, respectively. According to the results, it is stated that, by optimizing the concentrations of the ellicetors, it is possible to produce the desired secondary metabolites of salvia in in vitro conditions

Cadmium (Cd) is an environmentally polluting metal that has a negative effect on plant growth and yield. In this study, to understand the role of salicylic acid (SA) in alleviating cadmium toxicity in Sage (Salvia officinalis L.), the changes of biochemical and physiological indexes in Sage seedlings exposed to 0, 100, 200 or 300 ppm Cd with or without 0.1, 0.5 and 1 mM SA for 30 days was investigated. The results showed that Cd treatment reduced the growth, photosynthetic pigments, soluble sugars and activity of catalase and peroxidase enzymes, while increased proline content, phenolic compounds, MDA and H2O2. However, SA pre-treatment improved the growth and increased content of photosynthetic pigments, proline, soluble sugars and phenolic compounds at all levels of cadmium. Furthermore, SA pretreatment increased the activity of antioxidant enzymes catalase and peroxidase, and reduced MDA and H2O2, which reduced the cadmium-induced oxidative stress and, consequently, increased Sage tolerance to cadmium. According to our results, it seems SA might regulate the antioxidant defense activities, increase osmolyte and secondary metabolite compound in Cd-treated Sage, thereby improving growth and tolerance of Sage to Cd stress