مجله تحقیقات گیاهان دارویی و معطر ایران
سال بیست و هفتم شماره 1 (پیاپی 51، بهار 1390)

Cowpea weevil Callosobruchus maculatus (F.) is one of the serious post-harvest pests of stored products. The damaged seeds are unsuitable for human or animal consumption and also for farm cultivation. To control this pest in warehouses, usage of essential oils is considered as an appropriate alternative to synthetic pesticides. Therefore, a study was conducted to investigate oviposition deterrence and repellency effects of Thymus kotschyanus Boiss & Hohen and Mentha longifolia L. on C. maculatus. These plants were collected from around of Tehran. Essential oils were subjected to hydrodistillation using a Clevenger-type apparatus for 3 h. The experiments were done under dark condition in 27 ± 1 ˚C and 65 ± 5 % R.H. Essential oils significantly reduced oviposition of the adults as 500 µl of T. kotschyanus and M. longifolia essential oils (1800 ppm) caused 87.64 and 86.36% oviposition deterrence respectively. Also, essential oils had repellent activity on C. maculatus. At 800 ppm, repellency of M. longifolia and Thymus kotschyanus was recorded 90% and 73.33 % respectively.

This experiment was conducted to evaluate the effects of Satureja hortensis L., Ziziphora tenuir L., Urtica dioica L. and their different mixtures on yield, egg quality, blood and immunity parameters of laying hens. A 23 factorial experimental design was applied with 8 treatments in 1- control treatment or no medical plants, 2- 2% of S. hortensis, 3- 2% of Z. tenuir, 4- 2% of U. dioica, 5- 2% of (S. hortensis and Z. tenuir), 6- 2% of (S. hortensis and U. dioica), 7- 2% of (Z. tenuir and U. dioica) and 8- 2% of (S. hortensis, Z. tenuir and U. dioica) including 3 replicates in each treatment and 12 hens in each replicate for 12 weeks)25-37 weeks of laying period). The results showed that the use of different medicinal plant mixtures had significant effects on yield, and egg quality of laying hens (P<0.05). Maximum egg yield (86.622%) and egg mass (47.497 g) were recorded for 2% of U. dioica treatment whereas the maximum eggshell weight (5.804g) and unit (94.635%) were obtained by using 2% of S. hortensis. Using 2% of U. dioica also had positive effects on blood biochemical parameters and percentage of immunity cells. According to the results, using 2% of U. dioica in laying hen's diet could have positive effects on their yield, blood biochemical parameters and percentage of immunity cells.

Rosemary (Rosmarinus officinalis L.) is one of the medicinal plants exhibiting potential for secondary metabolite production. In the present study, the interaction effects of zinc nutrition and salinity on growth of Rosemary, total phenolic content, DPPH radical scavenging activity and ferric reducing antioxidant power (FRAP) were studied in a Zn deficient soil. Two zinc levels (0 and 10 mg kg-1 Zn as ZnSO4) and three salinity levels (0, 50 and 100 mM NaCl in irrigation water) were used as treatments in a factorial experiment based on completely randomized design with four replications. According to the results, salinity did not show significant effect on shoot dry weight production which indicates salinity tolerance of Rosemary. 100 mM NaCl salinity increased total phenolic content, DPPH radical scavenging activity and FRAP up to 3, 8 and 5 percent respectively. 10 mg Zn added to the soil also increased total phenolic content (2%), DPPH radical scavenging activity (4%) and FRAP (3%). The results of correlation test showed that increase of antioxidant activity in Rosemary grown under salinity condition was due to the increase of total phenolic content. Our findings suggest that salt stress and suitable Zn nutrition increase antioxidant compounds in Rosemary.

This research was performed in order to investigate flowering shoot yield, morphological characters, percentage and yield of essential oil and relationship between characters of two ecotypes of Mentha longifolia var. amphilema L. at Research Institute of Forest and Rangelands for six years in 1999 to 2004. This experiment was conducted as a split plot on time by using of randomized complete block design (RCBD) with three replications. Main and sub factors were ecotypes and years, respectively. The results showed significant differences between leaf oil yields, flower oil yields and flower yields in different ecotypes. There were also significant differences between all evaluated characters (plant height, leaf long, leaf width, stem diameter, lateral shoot, yield of flower, percentage and yield of flower essential oils, leaf yield, percentage and yield of leaf essential oils, yield of flowering shoots and their oils) at 0.01% level of probability in different years. There was significant relationship between total essential oil with yield of flowers and leaves and their essential oils at 0.01%level of probability. There was significant relationship between yield of flowering shoot with leaf long and lateral stem at 0.05% level of probability, and between yield of flowering shoot with leaf yield, essential oil percentage and yield of flower, leaf yield, essential oil percentage and yield of leaf at 0.01% level of probability. The results of stepwise showed that the model compounded of 4 characters: leaf oil yield, flower oil percentage, flower yield and stem diameter. The results of path analysis revealed that leaf oil yield (0.907) had a high direct effect on the dependent (total essential oil yield) variable. So results of path analysis revealed that flower oil percentage (0.019) had a high direct effect on the dependent variable after, yield of leaf essential oil.

In many countries, wastage of agricultural products is due to oxidative processes and microorganisms activity in warehouses. On the other hand, many plants are the sources of compounds with high antioxidant and antifungal activities that might be used as natural preservatives. To investigate the antioxidant and antifungal properties of pomegranate, a factorial experiment based on completely randomized design with 5 replications was conducted. In this study, the effect of 3 different pomegranate parts (peel, seeds and leaf) and 2 different kind of extracts (aqueous and methanolic) with 4 concentrations (0, 500, 1000 and 1500 ppm) were investigated on 2 post-harvest fungi (Alternaria citri and Aspergillus niger). According to the results, the methanolic peel extract showed the highest inhibitory effects on the mycelia growth (IMG) and spore germination (ISG) with 47.6 and 37.7 percent respectively. Also, phenolic compounds of peel extract were 1.8 times higher than that of pomegranate leaf extract. Antioxidant capacity of peel, seeds and leaf extracts was respectively 55.3, 35.7 and 16.4%. Therefore, it seems that high antifungal and antioxidant activity of peel and seeds of pomegranate are because of high percentage of phenolic compounds in these plant parts extracts.

After water, tea is the most consumed beverage around the world. Phenolic compounds constitute 50-70 % of tea water extract that Theaflavins (TF) and Thearubigins (TR) among them are of most important polyphenols as quality parameters of black tea. Agroclimatic conditions, tea variety and geographical origin are of effective factors on tea quality. This study was undertaken to quantify seasonal variations in quality- related, biochemical, and sensory parameters in manufactured orthodox Iranian tea over various months (June, July, August, September and October). TF, TR, TRSI and TRSII, total color, total polyphenols and brightness were measured by spectrophotometer method and the tea quality was estimated and scored by professional tea tasters. According to the results of ANOVA, phenolic compounds significantly differed in different tea plucking seasons (P<0.05). Drink obtained from green leaves in July tea plucking season had the highest total polyphenols (15.83%), Theaflavins (22.33 µmol/g), total color (3.01%) and brightness (28.85). Results of Pearson's correlation coefficients showed that correlation of total TR and TRSII with brightness was not significant while other measured parameters showed a significant correlation to each other. In view point of tea tasters, tea obtained from July and August had the highest total sensory scores while tea obtained from June received the highest tea aroma score. Spearman rank correlation coefficients indicated that there was no significant correlation between tea aroma and other sensory attributes while mutual correlation of other sensory attributes was positive and significant. This suggests that tea with high chemical quality should have good individual tea sensory attributes.

Thymus species are well known as medicinal plants because of having biological and pharmacological properties. Thymus daenensis is an endemic aromatic medicinal plant to Iran. Essential oil of Thymus daenensis is a rich source of thymol which gives high antimicrobial and antioxidant activity to this plant. In this research, the aerial parts of Thymus daenensis were collected at full flowering stage from Alborz Research Station in Karaj. For finding the effect of drying methods on essential oil yield and composition, the plant material were dried in four different conditions (oven 30°C, 40°C, 50°C and shade). After drying the samples, their essential oils were obtained by water distillation in three replications and were analyzed by GC and GC/MS. Oil yield and percentage of main components were statistically compared by Duncan's test in SAS software. Oil yields (w/w) of the oven-dried 30°C, 40°C, 50°C and shade-dried samples were 1.42%, 1.12%, 1.24% and 1.29%, respectively. Thymol (75.3%, 75.7%, 72.0% and 67.2%), allo-aromadendrene (5.7%, 5.2%, 5.4% and 3.9%), γ-terpinene (2.9%, 2.8%, 5.9% and 10.2%), p-cymene (4.2%, 4.1%, 5.1% and 5.5%) and carvacrol (2.2%, 4.1%, 1.6% and 2.4%) were identified as the main components in oven-dried 30°C, 40°C, 50°C and shade-dried samples, respectively. Statistical analysis showed a significant difference between oil yields of oven-dried 30°C sample with other samples. The highest percentage of thymol was obtained from oven-dried 30°C and 40°C that showed a significant difference with other drying methods.

In order to evaluate the effect of biofertilizers on the yield and quality of Dracocephalum moldavica L. essential oil, a field experiment was conducted at the Western Azarbaijan Agricultural Research Station in 2008. Randomized Complete Block Design was used including 9 treatments and 4 replications. Treatments were nitroxin, biological phosphorus, bio-sulfur, nitroxin + biological phosphorus, biological phosphorus + biosulfur, nitroxin + biosulfur, nitroxin + biological phosphorus + bio-sulfur, chemical origin of nitrogen + phosphorus + potassium and control (no fertilizer treatment). According to the results, the effect of treatments on dry matter yield (leaves), seed and biological yield, percentage and yield of essential oil and thousand seed weight was significant (P<0.01) while it was not significant on harvest index of leaves and harvest index of seed. Means comparison showed that applying chemical fertilizer (NPK) resulted in highest leaves dry matter, seed and biological yield. The highest essential oil content and essential oil yield respectively obtained from nitroxin + biological phosphorus + bio-sulfur and nitroxin biofertilizer. Considering the fact that no significant difference was observed between applying nitroxin and chemical NPK, it can be concluded that applying nitroxin may result in maximum seed and essential oil yield. In all studied traits, application of some biofertilizers was significantly better than control treatment (no fertilizer).

To investigate variations in the essential oil content and composition, leaves of three Eucalyptus species named E. melliodora, E. kingsmilli and E. dundasii were collected in the middle of four seasons during two years from two warm regions, Dezful and Shushtar in South of Iran. The essential oils were obtained by hydrodistillation and the oils were analyzed by GC and GC/MS. The maximum oil yield of E. melliodora was obtained in winter (3.1-3.9%) and spring (2.6-2.7%) from Shushtar samples, and in autumn (1.7-2.0%) from Dezful samples. The highest percentage of 1,8-cineole was found in winter and autumn in both regions. The maximum oil yield of E. kingsmilli was obtained in winter (2.8-3.1%) from Shushtar samples, and in authumn (2.7-3.2%) from Dezful samples. The highest percentage of 1, 8-cineole was found in winter and autumn in Shushtar and autumn, spring and winter in Dezful. The maximum oil yield of E. dundasii was obtained in winter (2.8-4.7%) from Shushtar samples, and in summer (0.9%) from Dezful samples. The highest percentage of 1, 8-cineole was found in spring and autumn in Shudhtar and spring in Dezful. There were also some variations in the amounts of other major and minor components. According to the results and to achieve a suitable quality and quantity of Eucalyptus essential oil, cultivation of E. melliodora in Shushtar and Dezful is recommended. For obtaining the highest oil yield and 1,8-cineole content from the mentioned Eucalyptus species, the best harvesting time for E. melliodora is spring and winter in Shushtar and autumn in Dezful. Cultivation of E. kingsmilli in Dezful is more suitable than that in Shushtar and the best harvesting time is spring and autumn in Shushtar and autumn in Dezful. Cultivation of E. dundasii is also recommended in Shushtar while not in Dezful due to its low yield and quality of essential oil. The best harvesting time for E. dundasii in Shushtar is winter (the highest oil yield) and spring (the highest 1, 8-cineole percentage).

Field studies were conducted over two growing seasons to study the effects of foliar application of cycocel (CCC) at early growth stage on grain yield and its components of (Carthamus tinctorius L.) cv. Isfahan, at Agricultural Research Station of Kerman University, using randomized complete block design with three replications. In the first year, the effects of 0, 1000 and 2000 mgL-1 was studied. Compared with control treatment, CCC had no effects on stem diameter and length, but significantly increased total branches, leaf number, flower head biomass, flower head number, 1000-grain weight, seed yield and biological biomass, with no effect on seed oil, seed protein percentage and harvesting index. In the second year, the effects of 0, 1000, 2000, 3000 and 4000 mgL-1 was studied. Compared with control treatment, cycocel up to 3000 mgL-1 increased total and lateral branches, flower head number, flower head biomass, 1000-grain weight, grain yield and biological biomass. In some cases, 3000 mgL-1 CCC was more effective than other concentrations. However, it can be concluded that, 1000 mg/lit cycocel applied at early growth stage significantly increases grains in safflower.

Nowadays, in response to the consequences of herbicide application and gradual reduction of farm crops, suitable biological methods have been identified to control the weeds. This research was conducted to evaluate the allelopathic effect of harmel (Peganum Harmala L.) on seed germination of oat (Avena fatua L.), fat hen (Chenopodium album L.) and pig weed (Amaranthus retroflexus L.) in laboratory and greenhouse conditions using hydroalcoholic extracts of harmel dried fruit powder. The treatments were 0.1, 0.25, 0.5, 1, 2.5 and 5% extract of harmel and distilled water (control). Laboratory results indicated that germination percentage and radicle and plumule lengths of weed species were significantly reduced by different harmel extracts in comparison with control. According to the results of greenhouse experiments, germination percentage, fresh and dry weight and height of weed species were significantly reduced by using hydroalcoholic extracts. Greenhouse results also showed that seed germination percentage of Chenopodium album, Amaranthus retroflexus and Avena fatua at concentration of 1% was reduced 60%, 50% and 40% respectively in comparison with control. Our results showed that harmel extract had strong allelopathic effects and inhibited seed germination of weeds recommended in production of natural herbicides.

In order to study callus induction, somatic embryogenesis and plant regeneration in fenugreek (Trigonella foenum-graecum L.) an experiment was conducted in Sari Agricultural Sciences and Natural Resources University during 2008. In the current experiment, different explants including stem segments, embryos, hypocotyls, etc. were cultured on two basal culture media viz. B5 and MS. Moreover, 2, 4-D, Kin, NAA, BAP and IBA were used as plant growth regulators. Result showed that the medium containing 2mgl-1 2, 4-D in combination with 0.5mgl-1Kinetin was the best treatment for callus induction in both MS and B5 media. Combination of 0.5mgl-1 NAA and 2.5mgl-1 BAP was the best treatment for somatic embryogenesis in both basal media. Also, combination of 1.5mgl-1 BAP and 0.5mgl-1 NAA was the best hormonal treatment to shoot regeneration in both basal media. According to the results, the treatment containing 1 mgl-1 IBA was optimum for root induction from regenerated shoots on MS medium.

In order to investigate the germination factors of two improved cultivars and one Iranian landrace of cornflower (Centaurea cyanus) under salt stress conditions a factorial experiment based on completely randomized design with two factors in three replications was conducted at experimental laboratory of department of horticulture, Ferdowsi University of Mashhad during 2009. The main factor included two improved cultivars of cornflower (Ball blue and Ball junge) and one Iranian landrace and second factor included seven salinity levels (0, 50, 100, 150, 200, 250 and 300 milli molar NaCl). Measured characteristics were germination percentage, germination velocity, vigor index, radicle and plumule length. According to the results of ANOVA, different levels of salt stress had significant effects on all measured characteristics while the effect of cultivar type was only significant on germination percentage, germination velocity and vigor index. The interaction between salinity and cultivar type had significant effect on all measured characteristics. The results showed that with increase in salinity level, all measured characteristics were significantly decreased. The most germination percentage and germination velocity (51.04 percent and 11.82 seed/day respectively) were obtained from Ball blue in control treatment and the lowest (9.32 percent and 0.5 seed/day respectively) was obtained from Iranian landrace and Ball junge cultivar in 300 mili molar NaCl. Decrease of plumule length was more than that of radicle length under salinity stress. In this study, improved cultivars of cornflower and Iranian landrace showed different responses to salt stress due to the diversity in their genotypes. Generally, Ball blue was identified as the most salt tolerance cultivar in germination stage.

In order to study the effects of irrigation time and nitrogen fertilizer on growth period, essential oil and chamazulene yield of German chamomile (Matricaria chamomilla L.), Bodegold variety, an experiment was conducted in a cold and semi-arid region, Tabriz, Iran, as split factorial with irrigation times (after 60, 120, 180 mm evaporation from pan), urea rates (50, 100, 150 kg ha-1, equivalent with 23, 46 and 69 kg ha-1 pure nitrogen) and urea splitting (100% in planting time, equally in planting and stem elongation stages, 25%:50%: 25% in planting, stem elongation and early flowering stages). Analysis of flower essential oil was done by GC/MS. Results showed that emergence of flower bud in treatments irrigated after 180 and 60 mm evaporation from pan, happened after 70 and 78 days respectively. Increasing of urea application delayed full flowering of chamomile. Delay in irrigation from 60 to 120 mm evaporation reduced dry flower yield up to 2.3%. Application of nitrogen fertilizer at two stages of planting and stem elongation increased flower yield up to 351 kg ha-1. Shoot dry weight of chamomile increased from 76 g m-2 in the third level of irrigation to 126 g m-2 in average of first and second levels of irrigation. The highest essential oil yield (2.82 l ha-1) was obtained when urea was equally applied at planting and stem elongation stages. After applying 50, 100 and 150 kg ha-1 urea, chamazulene content was respectively calculated as 0.31, 0.44 and 0.36 l ha-1. According to the results, for chamomile cultivation in this region and also other similar areas it is recommended that irrigation is done after 120 mm evaporation from pan and 46 kg ha-1 nitrogen is equally applied at planting and stem elongation stages.