مجله زیست فناوری گیاهان زراعی
پیاپی 40 (زمستان 1401)

Eurygaster integriceps is one of the known pests of wheat fields in Iran and West Asia. The role of neuropeptides in the stages of insect’s growth has led to a promising perspective for the production of a new generation of bio-insecticides based specific application. Insect’s neuropeptides along with their specific receptors are one of the most diverse proteins that control physiological and behavioral activities in insects. Allatostatin is one of the important neuropeptides in insects which, by inhibiting the youth hormone, plays a role in regulating physiological processes such as feed and metabolism in some insects. In this study, using the information obtained from adult Eurygaster integriceps transcriptome, neuropeptides and specific receptors of the allatostatin family were investigated. Bioinformatics and phylogenetic studies of the data led to identify four neuropeptides A, B and C allatostatin family, as well as the neuropeptide receptors of A and B allatostatin. The results showed that the neuropeptides of the allatostatin family identified in Eurygaster integriceps are involved in various physiological processes. Considering the important role of neuropeptides in insects, these neuropeptides can be used to design specific insecticides compatible with the environment for managing control Eurygaster integriceps in future.

Sunflower (Helianthus annuus L.) is an important oilseed crop that is cultivated worldwide because of its high-quality oil and be rich in linoleic acid. The present study is a review of the effects of salinity on morphological and physiological traits, resistance mechanisms, breeding, and agronomic methods to deal with salinity tolerance in sunflower. Sunflower is classified as semi-tolerant species. The negative effects of salt stress on sunflower include browning of root tips, reduction of cotyledons and root proliferation, leaf surface, accumulation of dry matter, yield, and seed oil content. Salt stress also leads to decrease in CO2 absorption, transpiration rate and stomatal conductance, and photosynthetic capacity in sunflower. The resistance reactions to salinity stress in sunflower include: modulating the expression of oubain-sensitive ATPases through calcium, delaying the degradation of membrane proteins of oil bodies, increase serotonin and melatonin, increase the expression of nitric oxide, increase S-nitrosylation of cytosolic proteins, increased content of lipid peroxide, activity of glutathione peroxidase, and the abundance of heme oxygenase-1 (HO-1) in the cells around the secretory channels . Among the important breeding approaches to cope salinity stress in sunflower are the identification of HT089, HT175, HT185, HT215, HT216, and HT227 salinity resistance genes, the identification of H. paradoxus as the most salinity resistant species, the production of HA429 and HA430 lines tolerant to salinity, the transfer of the TaNHX2 gene from wheat to sunflower that improved its salinity tolerance and the identification of genes involved in salinity stress in sunflower by next generation sequencing technology. The results of this extensive study will be important in achieving a comprehensive plan for sustainable improvement of yield and quality of sunflower oil under salt stress conditions.

Yew plant is the main source of Taxol drug production. Paclitaxol with the brand name Taxol is the main drug in the treatment of various cancers. This plant has a long dormancy and difficult germination and due to the, high demand and indiscriminate harvesting in some areas, there is a risk of extinction of this very important plant. According to these conditions, it is necessary to use the biotechnology tools such as tissue culture and embryo culture to produce new seedlings for propagation and use them in other laboratory studies. In this research, first in the form of a completely randomized experiment design with 48 treatments and three repetitions, it was determined that the treatment of 21 days of keeping the seeds in water and growing them on ½ WPM. cultivation environments have the highest germination. In the next step, in order to shorten the germination time, the embryos were isolated in a sterile environment kept in sterile double distilled water on a refrigerated shaker for 5 days at a temperature of 4°C and cultured in two cultivation environments ½ WPM and ½ MS Variance analysis revealed that there is no significant difference between treatments in germination speed, so it can be concluded that young and fresh seedlings can be obtained in less time with this method.

In order to achieve more high- yielding chickpea genotypes than the existing cultivars that have suitable traits such as seed yield, more number of pods per plant, coarseness of seeds , early maturity and other desired agricultural traits, 16 advanced chickpea genotypes selected from advanced tests comparing crop year yield 2015-2016 along with Adel and Azad witness figures for three crop years (2016-2019) in Gachsaran, Gonbad, Khoramabad and Ilam were planted in the form of a completerandomized block design with three replications. Composite variance analysis showed a significant effect of genotype, environment and genotype interaction in the environment (GEI)., Therefore, Biplot method was used to analyze the genotype × environment interaction. The first two principal components explained 32/50 percent (26.12 and 24.2%, respectively) of the total GEI changes. The polygon view of Biplot showed that genotypes 18, 9, 17 and 16 with higher than average performance and near the origin of Bioplate were genotypes with high general stablity. Also genotypes 5, 12 and 11 showed adaptation to many environments. The average tester view of Biplot also showed that genotypes 12, 18 and 9 were the closest genotypes to the ATC axis and therefore the most stable and also had high average yield in different environments. The ideal genotype view of Biplot showed that genotypes 5 and 12 at the closest distance from the Biplot origin were the best genotypes and genotypes 1, 2 and 13 were the most unfavorable genotypes in terms of seed stability and yield.According to the results, genotypes 5, 9, 12 and 16 were selected as promising genotypes and candidates for introduction.

Plants are able to acquire thermotolerance to the subsequent lethal stress through memorizing previous heat stress (HS) (Priming). A priming effect that can be sustained for several hours, days, or even generations after reverse heat stress, is called heat stress memory. The aim of this study was to identify effective key genes in establishing and maintaining heat stess memory. To achieve this, microarray data of the expression profile of Arabidopsis samples were retrieved from the GEO (Gene expression omnibus) database and differentially expressed genes (DEGs) were identified based on their higher transcriptional activation following recurring stress (in P+T/P treatment comparison) and their sustained induction even 52 hours after stress relief (during memory phase).The identified genes were further analyzed by bioinformatics tools for gene ontology (GO) classification and protein-protein interaction (PPI) networks. GO terms analysis disclosed that the up-regulated DEGs were mainly associated with cellular response to heat, heat acclimation and protein folding. By clustering of PPI networks in the term related to response to heat (in P+T/P treatment comparison), several candidate genes involved in thermomemory were identified including HSP70T-2, HSP91, AR192, HSP60, HSP70, BIP2, J2, CLPB4, HOP3, HSP101, ROF1, HSFA3, HSFA2, HSP70B, CLPB3, FES1A, MBF1C. Also, based on the sustained differential expression of genes even 52 hours after the priming phase, it was determined that genes responsible for maintaining heat stress memory were mainly members of the small heat shock protein family (sHSPs) such as HSP17.6, HSP21, HSP17.6II, HAS32, HSP17.4, HSP18.2 and HSP22. KEGG (Kyoto Encyclopedia of Genes and Genome) pathway analysis revealed that the HS memory genes were mainly involved in protein processing in the endoplasmic reticulum (ER) and oxidative phosphorylation. Furthermore, the analysis of cis-regulatory elements in the promoter regions of the thermomemory genes revealed that the transcription factors families of bZIP, AP2;B3;RAV, MYB/SANT, HD-ZIP and GATA; tify had the highest binding sites in their upstream regions. In summary, these findings provide useful information about functional and regulatory analysis of genes involved in the establishment and maintenance of heat stress memory, as well as their protein network interactions. This information can be used to improve the heat tolerance capacity of plants under extreme heat stress.

To study the effect of different levels of melatonin on the biochemical properties and the amount of expression of genes related to the activity of antioxidant enzymes in bread wheat, a split plot experiment was conducted based on a randomized complete Triticum aestivum block design. Irrigation levels (normal (FC = 80%)), mild stress (FC = 60%), and severe stress (FC = 40%)) were allocated to the main plots and melatonin foliar spray (zero, 50, 100, 150, and 200 μM) were assigned to subplots. The results showed that the flavonoid content and ascorbate peroxidase enzyme activity increased with the intensification of dehydration stress. The level of 100 µM melatonin had the highest flavonoid content, ascorbate peroxidase enzyme activity. The mean comparison interaction treatments showed that the highest content of proline, phenol, superoxide dismutase and catalase was assigned to the 100 µM melatonin foliar spray under conditions of extreme stress of dehydration. Also, the lowest amount of malondialdehyde was observed for the 50 μM melatonin foliar treatment under normal irrigation conditions. The highest content of chlorophyll a, chlorophyll b, carotenoid and grain yield were recorded in the treatment of foliar spray of 100 μM melatonin and normal irrigation conditions. In this investigation, the maximum expression of superoxide dismutase, ascorbate peroxidase, polyphenol oxidase and catalase genes were determined in the foliar spray of 100 and 150 μM melatonin levels under conditions of extreme stress. . The foliar spray of melatonin, especially at the level of 100 μM, could moderate the effect dehydration stress on grain yield by improving biochemical and antioxidant properties.

Nitrogen is one of the most important components of biomolecules, amino acids, nucleotides, proteins, chlorophyll, and many plant hormones, which are essential and necessary for plant growth and development. In the condition of nitrogen deficiency very different responses such as yield reduction, leaf chlorosis, plant growth and root structure formation appears in phenotypes of plants. In the last decade, to increase the amount of biomass and as a result the yield of plants, a wide use of nitrogen has attracted the attention of researchers. In this study, the expression analysis of seven nitrate transporter genes (NRT2) was investigated in Arabidopsis in response to nitrogen deficiency stress at 4 and 7 days after this stress. The expression analysis of NRT2.3 and NRT2.4 genes showed increased expression at 7 days after applying nitrogen deficiency stress. But all the genes did not show a significant increase in expression at 4 days after N stress application. NRT2.4 gene showed a significant increase in 4 and 7 days after applying nitrogen stress compared to other genes. Overall, our results showed that increased nitrate transporter gene expression in leaves contributes to nitrogen uptake for plant growth and nitrogen accumulation in response to long-term low nitrogen stress. These findings can lead to a better understanding of the mechanism of low nitrogen tolerance and therefore the increase of other cultivars with nitrogen deficiency stresses.