فصلنامه گیاه و زیست فناوری ایران
سال نوزدهم شماره 1 (بهار 1403)

This study was conducted to investigate the growth and physiological responses of tomato (Solanum lycopersicum) plants to long-term foliar application of zinc oxide (ZnO) and salicylic acid (SA) in low concentration. This experiment was carried out under the pot conditions in cocopeat and perlite medium and Hoagland's nutrient solution was used to irrigate tomato seedlings. Tomato seedlings were sprayed with two concentrations (0 and 5 mg/l) zinc oxide and/or two dose (0 and 5 mg/l) of salicylic acid with three-day intervals during two months. Single and combined foliar application of salicylic acid and zinc oxide improved plant growth and fruit fresh weight. The applied treatments increased plant height, shoot fresh weight, root fresh weight, and fruit fresh weight. Individual and combined treatments of salicylic acid and zinc oxide also significantly increased the content of photosynthetic pigments, including chlorophyll a (Chla), Chlb, and carotenoids. A significant increase in the activity of catalase enzyme was recorded due to the foliar spray of zinc oxide and salicylic acid, especially the combined treatment. Peroxidase enzyme activity also showed an increasing trend in response to foliar application of zinc oxide and salicylic acid. Overall, this study provided physiological evidence on how the application of ZnO and salicylic acid in appropriate concentration can improve primary metabolism and antioxidant system. It is obvious that performing further researches, especially at molecular levels, can improve our knowledge in the field.

This study was conducted to investigate the effect of drought stress and plant population on re-transfer of materials and yield and some yield components of wheat cultivars in Dorud and Boroujerd regions located in Lorestan province in the crop year 2019-20. The experiment was performed as a factorial split-plot in a randomized complete block design with three replications. Drought stress treatment (in three levels of control, irrigation to flowering and irrigation to milk development) was plant density treatments (300, 400, 500 and 600 plants per square meter) and cultivar (Mihan and Baharan) were stand in sub plots. The results showed that drought stress, density and cultivar treatments had an effect on grain yield components and the interaction effect of stress * plant density on spike length and leaf area was significant. Also, the interaction effect of location * stress * cultivar on plant height, spike length and 1000-seed weight was significant. The highest plant height was obtained in irrigation treatment up to the milk development stage and Mihan cultivar cultivated in Boroujerd. The spike length in irrigation treatment up to flowering stage and at the level of 600 plants / m2 was higher than other experimental treatments. The highest number of spike per plant was in the control treatment. The highest 1000-seed weight was obtained in Mihan cultivar at the level of complete irrigation treatment in Dorud region and the highest grain yield was obtained in full irrigation treatment.

This study was carried out in order to investigate the effect of chemical fertilizers application on the amount of rapeseed infestation by wax aphid and the agricultural characteristics of rapeseed. Experiment was conducted as a three-factor factorial based on a randomized complete block design in three replications. The experimental factors include the application of nitrogen fertilizer at three levels (175, 250 and 325 kg.ha-1) from the source of urea fertilizer, phosphorus fertilizer at three levels (70, 100 and 130 kg.ha-1) from the source of triple superphosphate fertilizer and sulfur fertilizer in There were two levels (25 and 50 kg.ha-1). The results showed that increasing the application rate of nitrogen fertilizer led to a decrease in the pollution index, the percentage of infected plants and the length of the infected stem, as a result of which the grain yield and biological performance increased. The results showed that the use of higher amounts of chemical fertilizers led to an increase in the components of rape seed yield, so that the highest number of seeds per pod in the treatment of application of 100 kg.ha-1 phosphorus along with 25 kg.ha-1 sulfur and the highest 1000 seed weight was obtained in the application treatment of 130 kg.ha-1 of phosphorus along with 50 kg.ha-1 of sulfur. The increase in the amount of grain yield components led to an increase in grain yield and biological yield, so that the highest amount of grain yield and biological yield was 3804 and 12836 kg.ha-1, respectively, in the treatment of application of 325 kg.ha-1 of nitrogen fertilizer. Based on the results of this study, it was found that the application of 325 kg.ha-1 nitrogen fertilizer reduced the rate of contamination of canola with wax aphid and increased the grain yield, which can be recommended for the farmers of the region in the cultivation of canola

In order to investigate the effect of drought stress on the physiological and biochemical traits of six grape cultivars, a factorial experiment was conducted based on a completely randomized design with three replications under greenhouse conditions. In this experiment, the treatments included six Khorasani and shirazi grape varieties (Askari, Khalili, Yaquti, Pikami, Turkmen 4 and Suzak) and four levels of drought stress (normal conditions (100% of the farm capacity), low stress (75% of the farm capacity), medium stress ( 50% of farm capacity) and severe stress treatment (25% of farm capacity). The results showed that physiological and biochemical traits increased significantly with increasing stress intensity. On the other hand, the traits of relative leaf water content, membrane stability index, amount of photosynthetic pigments, and total phenol content decreased significantly with increasing stress intensity. Among the cultivars studied, the Yaqouti cultivar showed more resistance to drought than other grape cultivars in terms of the studied indices. According to the results of this research, it seems that Yaghuti cultivar is more drought tolerant than other cultivars. Since this tolerance located in leaf via active mechanisms, it is necessary to carry out additional tests when using Yaghuti as rootstock for scion of grapevine.

Considering the similarity of morphology and properties of different populations of savory (Satureja spp.), the separation of its species from each other requires additional and more detailed studies. Accordingly, S. avromanica and S. edmondi, two endemic species of Iran, were studied for their karyotypic and phytochemical characteristics. For cytogenetic studies, several traits such as total chromosome length (TL), long-arm length (LA), short-arm length (SA), centromeric index (CI), overall chromosome shape (%TF), relative length difference (DRL), intrachromosomal asymmetry index (A1), interchromosomal asymmetry index (A2), dispersion index (DI), and karyotypic formula (KF) were measured and calculated for populations 48 and 55 from Edmondi savory and 63 and 67 from Oramani savory. Based on the results, the basic chromosomal numbers in Oramani and Edmondi populations were x=12 (2n=2x=24) and x=15 (2n=2x=30), respectively. In cluster analysis based on complete linkage method, populations 63 and 67 were located in one cluster, however, 48 and 55 were placed in another cluster. Furthermore, the populations of the two species had statistically significant differences with each other for all the karyotypic traits (P<0.01). Based on GC-MS analysis, 21 and 25 different compounds were detected in Edmondi and Oramani savory essential oils (EOs), respectively. The main compounds in the EO of Oramani savory were piperitone (19%) and piperitenone (26.3%), while the main components in Edmondi savory EO were p-cymene (63.2%), thymol (5.7%), and γ-terpinene (8.8%). The highest (1.36%) and lowest (0.42%) EO yields were calculated for populations Oramani 63 and Edmondi 48, respectively. Therefore, these two mentioned species are considered as independent and distinct species from each other. Additionally, conducting additional studies to investigate the genetic diversity of these two species by different molecular markers can be important in confirming the present results.

Werrie PY, Durenne B, Delaplace P, Fauconnier ML. 2020. Phytotoxicity of essential oils: Opportunities and constraints for the development of biopesticides. A review. Foods. 9: 1291. Zhang J, An M, Wu H, Li Liu D, Stanton R. 2012. Chemical composition of essential oils of four Eucalyptus species and their phytotoxicity on silverleaf nightshade (Solanum elaeagnifolium Cav.) in Australia. Plant Growth Regulation. 68: 231–237. Biological herbicides based on extracts and essential oils of medicinal plants Abstract The use of herbicides has long been considered the most efficient method of weed control in agricultural production all over the world. However, the long-term use of agrochemicals has several negative effects on crops and the environment. In recent years, the development of new products based on bioactive compounds for the biological control of weeds has become important because it helps to reduce the use of synthetic compounds and herbicides in agriculture. Synthetic herbicides can lead to adverse effects such as human diseases and also disrupt the environment due to their movement in the air and persistence in different environments. It seems that the use of natural molecules is a very good alternative to maintain sustainable agriculture without the negative side effects of synthetic herbicides. In this context, extracts and essences of medicinal plants and their components are known thanks to their biocidal activities. Essential oils are an important source of biologically active compounds, oxygenated terpenes, and mono and sesquiterpenes play the main role in the phytotoxicity of essential oils. Essential oils and their components, mainly terpenoids, as pure or mixed natural compounds, can be good candidates for new biological herbicides or as raw materials for new synthetic herbicides due to their structural diversity and strong phytotoxic activity. Keywords: horticulture, biological properties, phytotoxicity, sustainable agriculture, secondary metabolites