Journal of Plant Physiology and Breeding
Volume:13 Issue: 2, Summer-Autumn 2023

Strawberry (Fragaria ananassa cv. Gavieta) are infected with several important viral diseases. In vitro culture of the meristem-tip is a valuable method in recovering pathogen-free plants and micropropagation of such crops. In this study, the effects of meristematic dome size, medium type and phenol inhibitors (AC, PVP and ascorbic acid) were investigated on the shoot tip culture of strawberry. Also the effect of plant growth regulators on shoot elongation was investigated. As the base medium, shoot tips were cultured on the MS media supplemented with 1 mg/l 6-benzylaminopurine (BAP) and 0.2 mg/l indole-3-acetic acid (IAA). The highest regenerated shoots were obtained with the meristematic dome with two leaves. The type of medium (liquid, semi-solid, and solid) significantly affected shoot tip proliferation, and the highest percentage of shoots were observed in the semi-solid medium. In the semi-solid medium all meristems were regenerated and produced more shoots with 8.55 mm length. Application of the phenol-absorbing and antioxidant compounds in the culture medium improved shoot induction and shoot performance. The best result was obtained in the medium supplemented with 500 mg/l polyvinylpyrrolidone (PVP) with 5 shoots, in which browning and explant death were avoided by absorbing phenolic substances from the explant.

Willow herb (Epilobium sp.) is a medicinal plant that is used for various purposes in the traditional medicine and food industries. In this research, an attempt was made to assess morphological and phytochemical variations in eight Epilobium species (E. hirsutum, E. Parviflorum, E. roseum, E. algidum, E. anatolicum, E. confusum, E. frigidum, and E. lanceolatum). The species were collected from natural habitats during the flowering period. Analysis of variance showed a significant variation among the studied species for measured morphological and phytochemical traits. Total phenolic content varied from 194.64 ± 1.17 to 309.10 ± 5.59 mg g-1 DW, total flavonoids ranged from 39.03 ±0.21 to 56.14 ±0.67 mg g-1 DW, and antioxidant activity differed from 43.03 ± 2.20 to 101.36 ± 3.68 mg g-1 DW. The results showed that E. frigidum is the richest source of natural antioxidants among the studied species, and also has the highest seed and leaf lengths. Antioxidant activity was significantly correlated with bioclimatic variables. However, the dendrogram based on morphological traits was relatively different from that based on all phytochemical variables. In conclusion, the remarkable variation among species for the morphological and phytochemical traits may be exploited in the breeding programs of the genus Epilobium.

To evaluate the genotype × environment (G × E) interaction and stability of grain yield in the Kabuli type chickpea (Cicer arietinum L.), 15 white chickpea genotypes were evaluated in a randomized complete block design with four replications in Kurdistan, Maragheh, and Zandjan stations during three successive years under spring dryland conditions. Combined analysis of variance showed significant variation (p < 0.05) among the genotypes for grain yield. The results of AMMI (additive main effects and multiplicative interaction) analysis showed that the two first components (PC1 and PC2) of interaction were highly significant (p < 0.01) and accounted for 52% and 34% of the G × E interaction, respectively. The AMMI model determined the best combinations of genotypes and environments for grain yield. FLIP 09-369C had the highest level of stability under the present test conditions, which can be considered as a new cultivar. Also, the interaction effect of GE was studied by the GGE biplot method. According to the singular value decomposition, the first two principal components explained 52% and 34% of the total variation. Based on the GGE biplot method, the genotypes FLIP 09-369c, FLIP 09-365c, and FLIP 09-247c had higher grain yield and stability than other genotypes. The GGE biplot analysis divided the environments into two mega-environments including KURDISTAN-MARAGHEH and ZANDJAN, and for each mega-environment, FLIP 09-369C and FLIP 09-251C lines were recommended, respectively. The study also indicated that FLIP 09-364C, Samin, and FLIP 09-212C were identified as lines with general adaptability.

This study aimed to investigate the response of cow cockle (Vaccaria hispanica (Mill.) Rauschert) ecotypes from northwest Iran to salinity stress at the germination and adult plant stages via a factorial experiment based on a completely randomized design with three replications in 2021. The results showed significant differences among the ecotypes regarding the germination components and morpho-physiological traits, indicating the existence of genetic diversity among them. Germination percentage and its components decreased with increasing salinity levels. So, at the NaCl concentrations greater than 120 mM, seed germination was inhibited in all studied ecotypes. This indicated that the cow cockle is a salinity-sensitive species and does not tolerate high salt concentrations. At the adult plant stage, salinity decreased plant height, root and stem dry weights, chlorophyll a and b content, and increased shoot sodium content and sodium to potassium ratio. The estimation of the multi-trait genotype-ideotype distance index (MGIDI) for different ecotypes based on various traits showed that the E3, E8, and E6 ecotypes having the lowest MGIDI values under salt stress conditions at both germination and adult plant stages, were the most tolerant ecotypes. Moreover, the E7 and E1 ecotypes had the highest MGIDI values at both growth stages and showed a higher sensitivity to salt stress. The more tolerant ecotypes selected based on the MGIDI indicator can be used for further research and selection in the breeding programs of this plant.

Expressed sequence tags of simple sequence repeats (EST-SSRs) are used to investigate genetic diversity and develop molecular markers for plants under biotic and abiotic stresses. However, there are a limited number of molecular markers based on the ESTs in rice to cope with the abiotic stresses including salinity, for use in breeding programs. Among 8299 ESTs, available in the NCBI database for salinity stress, 525 contigs, and 1139 singleton sequences were obtained. Twenty EST-SSR markers could be introduced for the selection of tolerant varieties to salt stress in rice by analysis of contigs and singletons. In contigs and singletons, significant common gene ontology terms are mainly related to the single-organism cellular process and response to abiotic stresses. The highest percentage of transcription factors for contigs and singletons was related to ERF, Dof, MYB, C2H2, BBR-BPC, bZIP, and WRKY. Moreover, the HSP81-2 (heat shock protein 81-2) and regulators of complement activation were identified as proteins of hub genes that were related to the salt stress tolerance mechanisms. Three uncharacterized hub genes (OS02T0161900-01, OsJ_19443, and OsJ_04035) including EST-SSRs for function identification were investigated by the 3D protein structure homology-modeling. OS02T0161900-01 as tetra ubiquitin, OSj-19443 as a serine/threonine-protein kinase/endoribonuclease, and OSj-04035 as a triosephosphate isomerase were identified. Most of the hub genes were related to environmental stresses and our findings provided candidate genes and transcription factors involved in salinity stress. The development of functional markers associated with abiotic stress tolerance will be helpful to facilitate rice breeding programs. However, before using these markers, laboratory confirmation is necessary.

Information about the amount of genetic diversity in the germplasm and genetic relations of genotypes is essential for analyzing and designing breeding programs and could be used for assisting in genetic identification and improvement of the germplasm. In this research, the genetic diversity of 48 genotypes of the flue-cured, burley, and oriental types of tobacco was investigated by 12 ISSR, 10 SSR, and five IRAP primers. The maximum number of bands was observed in the UBC825, RTR-10, and mixed primer UBC817 + UBC826 with 17 bands, UBC817 with 16 bands, and RTR-8 with 15 bands. UBC824 with 10 and UBC823 with 11 bands showed the minimum number of bands among ISSR and IRAP primers, and PT30044 and PT30046 primers with two alleles showed the minimum number of alleles among SSR markers. In ISSR and IRAP, the observed percentage of polymorphism ranged from 76.92% for RTR-1 and RTR-7 to 94.11% for RTR-10, and in SSR markers, it was 100%. The average polymorphism percentage was 90.7%, which indicated suitable genetic diversity among the tobacco genotypes. The polymorphism information content ranged from 0.31 to 0.5 with an average of 0.42. The average diversity of Nei and Shannon indices were 0.39 and 0.58, respectively. Cluster analysis by the UPGMA method classified the 48 tobacco genotypes into five groups, containing 5, 12, 10, 6, and 15 genotypes, respectively. Principal coordinate analysis showed that the 14 first components could explain 51.49% of the total variance. The primers used in this study had high efficiency, which can be used to study the genetic diversity in tobacco.

Polyploidy, a common phenomenon in the evolution of plant species, plays an imperative role in plant diversification. Bride rose poppy (Papaver fugax Poir.) is a valuable medicinal plant due to its various alkaloids, such as fugapavin, mecambrin, romerine, salutaridine, protopine, and thebaine. In this study, we used quantitative polymerase chain reaction (qRT-PCR) to study the differential expression of four key genes, including CYPB80B1 ((S)-N-methylcoclaurine-3’-hydroxylase), MLP (major latex protein), 6OMT ((S)-norcoclaurine-6-O-methyltransferase), and salAT (7(S)-salutaridinol-7-O-acetyltransferase), involved in the biosynthesis of poppy alkaloids. The assessment of extracted RNA samples on 1% agarose gel electrophoresis and NanoDrop showed the proper quality and quantity of isolated RNA samples for cDNA synthesis. Gene expression analysis through qRT-PCR revealed increased expression of CYP80B1, MLP, and SalAT genes and decreased expression of 6OMT in tetraploid plants compared with diploids. Our results indicated that autotetraploidy induction could be applied, as a useful method, to increase morphine production in P.  fugax.

Stem rust or black rust is one of the most important fungal diseases that widely affect wheat yield and quality in the world. Therefore, the selection of genetic materials resistant to stem rust in the breeding programs is necessary. In this study, 24 winter wheat genotypes including eight varieties and 16 elite lines were evaluated at the adult plant and seedling stages using a randomized complete block design under the influence of local stem rust race TKTTF. Disease indices including the type of infection, the severity of infection, the coefficient of infection, the area under the disease progress curve (AUDPC), the relative area under the disease progress curve (rAUDPC), and genotype reaction were recorded. Significant differences were observed among the genotypes for all disease indices. Based on all indices, MV-17 and C-98-17 were resistant and C-98-14, C-98-9, Bolany, and Morocco were susceptible. Pearson’s correlation coefficients revealed a significant positive correlation between field type of infection, the severity of infection, the coefficient of infection, AUDPC, and rAUDPC at the field, and between greenhouse type of infection and genotype reaction at the greenhouse. Based on cluster analysis by Ward’s method, all the genotypes were classified into four groups (R, MR, MS, and S) in the adult plant stage and into two groups (R and S) at the seedling stage. The resistant genotypes can be used in the breeding programs for improvement of the stem-rust-resistant genotypes.

Folates are a vital necessity for the retention of normal cellular activity. In contrast to humans, other organisms including plants gain folate coenzymes via de novo synthesis. GTP cyclohydrolase I (gtpch I, EC 3.5.4.16) catalyzes the first step of the biosynthesis of tetrahydrofolate (FH4) in plants by the conversion of GTP to dihydroneopterin triphosphate and formic acid. In this research, the expression pattern of the Vvgtpch I gene was assayed in different organs of the grape by the semi-quantitative RT-PCR. The analyses demonstrated that the Vvgtpch I gene was expressed in all grape organs. The highest amounts of expression were obtained in berry and leaf, whereas the lowest amount of Vvgtpch I transcript was related to the cluster. The response of Vvgtpch I gene to abiotic stresses was also investigated under the alkali and cold stresses by the semi-quantitative RT-PCR. Under the alkali stress, the transcript level of Vvgtpch I gene decreased considerably. Similar to the alkali stress, the transcript level of Vvgtpch I gene decreased under cold stress as well. To analyze the Vvgtpch I gene expression under oxidative stress, different treatments were applied such as chemical inducers, heavy metals, and plant growth regulators to trigger the production of reactive oxygen species. The Vvgtpch I showed a strong increase and a moderate increase in the transcript amount with Cu2+ and H2O2, respectively. Whereas, its transcript level was relatively down-regulated by the heavy metals and hormonal treatments, and almost disappeared by diamide.

This study aimed to evaluate the variation in agronomic traits of 361 cultivated oat genotypes and to identify superior genotypes for oat breeding programs. The experiment was conducted as a simple square lattice design with two replications for two growing seasons (2018-2019 and 2019-2020) in Kermanshah, Iran. There was a significant difference among oat genotypes. The highest grain yield (GY) was obtained in the “OX87:080-2” and “LA Prevision” genotypes. Furthermore, genotypes “Rubida” and “VDO-931-1” were superior regarding the biomass. Several analyses were performed using the best linear unbiased prediction estimates. The correlation coefficients showed a significant positive relationship between GY and biomass, 1000-kernel weight (TKW), and the number of panicles per plot. Biomass was positively and significantly correlated with all studied traits, except TKW. The number of grains per panicle (NGPP) and TKW had the highest positive direct effects on the GY and NPPP imposed the highest positive indirect effect through TKW. While the highest negative indirect effect was exerted by the NGPP through the TKW. The results of pseudo-F for cluster analysis grouped genotypes in five separate groups. The fifth group had the highest values ​​for GY, biomass, TKW, and NPPP. So, these genotypes could be considered as qualified parents to produce superior lines in breeding programs.

Estimates of combining ability are useful in determining the value of watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) lines in producing new hybrids with high yield and better quality. This research was conducted to estimate the general combining ability (GCA), specific combining ability (SCA), and heterosis for five inbred lines chosen for watermelon breeding at the University of Guilan, Iran. Analysis of variance indicated significant differences among hybrids for fruit weight and the number of lateral branches per plant. The GCA and SCA effects were significant for fruit weight and the number of lateral branches, which indicates the existence of both additive and dominance effects in controlling these two traits. The low narrow sense heritability indicated the smaller impact of additive gene action on fruit weight and the number of lateral branches in watermelon. However, broad sense heritability was high for fruit weight (0.69) and the number of lateral branches (8.88). The large gap between the broad sense heritability and narrow sense heritability indicated the importance of dominance effects in controlling the fruit weight and the number of lateral branches compared to additive effects. These results justify the development of hybrid varieties to exploit the dominance genetic effects in watermelon. The highest fruit weight and the number of lateral branches belonged to the S × Red cross. The highest SCA for the fruit weight was associated with the cross An × S. The cross S × Red had the highest SCA for the number of lateral branches. The high-parent heterosis was also higher in the cross S × Red for these traits. In conclusion, the hybrid S × Red may be proposed for the production of a hybrid variety in watermelon. However, crossing among various genotypes to produce new inbred lines seems necessary for the hybrid breeding program of watermelons in Iran.

In this study, a pollination experiment on almond species was conducted about the pollen tube penetration in the pistil with a fluorescence microscope and the rate of fruit formation by the controlled pollination in the orchard. These species included two new almond genotypes of KD 13 and K11-8 as pollen receptors, and two almond cultivars Tuono (self-compatible) and D5 (self-incompatible), a peach cultivar HolouYazdi, and GN15 (hybrid between almond and peach) as donor pollen sources. This experiment was conducted in an almond orchard with six-year-old trees at Kamal-Shahr Horticulture Research Station in Karaj, Iran. The results showed a significant difference among pollen sources for in vitro pollen grain germination. The pollen germination percentage ranged from 45 to 86% in the cultivars and genotypes under study. There were significant differences among crosses for the rate of pollen tube penetration in different parts of the style. KD13 × D5 (self-incompatible (with 9.6% and K11-8 × D5 (self-incompatible) with 7.63% showed the highest percentage of pollen tube penetration but KD13 × Tuono and K11-8  ×Tuono with 1% and 2.12%, respectively, had the lowest pollen tube insertion into the style. Ninety days after pollination, the crosses of KD13 × KD5 and K11-8 × D5 showed the highest percentage of fruit set (48.90 and 42.45%, respectively) as compared to other pollinizers. It was determined that the fruit formation was mainly influenced by the pollen source and therefore the source of pollen had a decisive role in the final fruit set. As a result, it is important to choose the right pollen source in the breeding programs before recommending the cultivation of new almond varieties.

In plants, melatonin (N-acetyl-5-methoxytryptamine) contributes to various environmental stress responses and developmental processes. Accordingly, the effect of seed priming with melatonin (1250 µM) on increasing salt tolerance at 40 dS m-1 NaCl was studied in Chenopodium quinoa var. Titicaca (quinoa) using a factorial experiment based on a completely randomized design at Shahrekord University in 2019. In the present experiment, different levels of NaCl and melatonin were first applied and according to the obtained results, 1250 μM melatonin and 40 dS m-1 NaCl were selected for the main study. The measured traits and indices included the fresh and dry weight, the content of photosynthetic pigments, hydrogen peroxide (H2O2), malondialdehyde (MDA), as well as the activity of catalase, ascorbate peroxidase, and guaiacol peroxidase. Seed priming with melatonin reduced the adverse effects of NaCl in the salt-stressed quinoa plants by increasing the dry weight (two-fold) and the level of photosynthetic pigments (1.2-fold) compared to the salinity stress alone. Also, the application of melatonin by changing the activity of antioxidant enzymes, reduced the content of H2O2 by 25% and MDA by 42%, which resulted in the reduction of oxidative stress in the quinoa plants under salinity conditions. Overall, it can be concluded that seed priming with an optimal level of melatonin can be a proper technique to increase salt tolerance in quinoa under highly saline conditions by reducing the harmful effects of salinity-induced oxidative stress by reducing the H2O2 and lipid peroxidation levels. It also protects the photosynthetic machinery by reducing the degradation of photosynthetic pigments which leads to the increased growth of the quinoa plants under salinity conditions.

Quinoa (Chenopodium quinoa Willd) is a plant with high nutritional value and has good adaptability to different growing conditions. To investigate the effects of planting date and density on the seed quality of three quinoa genotypes (Q29, Titicaca, and Red Carina), a field experiment was conducted in 2019-2020 at the research field of Agriculture and Natural Resources Campus, Razi University, Kermanshah, Iran. The seeds were sown on three dates (15th March, 15th April, and 15th May) under two planting densities (40 and 60 plants/m2). The experiment was conducted as a split-plot factorial design based on the randomized complete block design with three replications. The results revealed that both sowing date and plant density influenced the nutritional composition of the quinoa genotypes. The grain yield varied between 1642 and 2351 kg/ha, and the amino acids profile varied according to planting date and planting density. The amino acids histidine, glutamic acid, leucine, and lysine increased with delaying sowing date whereas threonine, tyrosine, arginine, methionine, glycine, proline, isoleucine, valine, serine, alanine, aspartic acid, asparagine, cysteine, phenylalanine, and glutamine decreased with delaying the sowing date from 15 March to 15 May. The Titicaca genotype produced maximum grain yield under the third sowing date while in the case of the first sowing date, all studied genotypes were more responsive regarding most amino acids. Also, the most suitable plant density to result in the highest grain yield was 60 plants/m2. The mineral content of the quinoa seeds was not influenced significantly by the sowing date, plant density, genotype, and their interactions, except for calcium which was affected significantly by the genotype. The lowest saponin content was observed in Titicaca under the planting density of 40 plants/m2. These results indicated that both sowing dates and plant densities influence the nutritional composition of quinoa genotypes.

A field experiment was laid out as a split-plot design based on the randomized complete block design with three replications in 2018, to assess the responses of oilseed rape (Brassica napus L.) plants to the foliar treatment of nanoparticles (ZnO and MgO) under different watering levels (I1, I2, I3, I4: Irrigation after 70, 100, 130, and 160 mm evaporation as normal irrigation, and mild, moderate, and severe stresses, respectively). Water shortage increased leaf temperature and decreased leaf water content, membrane stability, chlorophyll content, and plant biomass, which resulted in the reduction of the grain yield per unit area. Foliar application of nanoparticles enhanced grain and oil yields of oilseed rape by reducing some detrimental impacts of water limitation on leaf temperature, chlorophyll content, membrane stability, plant height, plant biomass, grains per plant, and 1000-grain weight. Therefore, foliar spray of these nanoparticles could be a superior treatment for alleviating some of the adverse effects of drought stress on the physiology and productivity of oilseed rape plants in the field.

Asparagus (Asparagus officinalis L.) is a perennial vegetable crop with different ploidy levels. The translocation of assimilates in diploid (2X) and octoploid (8X) asparagus between rhizome and fern needs to be understood. Transfer of soluble sugars, pigments, and invertase activity were studied in the two-year-old asparagus from May to November 2019. Sucrose and glucose were the major soluble carbohydrates in the asparagus rhizome. In the case of 2X asparagus, there was a balance of total sugars in the fern and rhizome, as opposed to anthocyanin. May and September were critical stages in the consumption or storage of substances in 2X asparagus. Sucrose transferred from fern to rhizome from August to October in 2X and 8X. Total sugars in rhizome decreased from May to June in 2X and 8X. Invertase activity increased from May to June and after that declined in both 2X and 8X. The growth of fern was dominant to the rhizome until August and the loading of glucose in the rhizome was low. The discriminant analysis indicated the difference in the response pattern of the 2X and 8X asparagus, where the rhizome fructose, fern carotenoid, and rhizome glucose in 2X but the rhizome sucrose, rhizome total sugars, fern fructose, fern anthocyanin, fern invertase, and fern sucrose were the most influential variables in these two types of asparagus. The total sugars, sucrose, glucose, and fructose transfer patterns in diploid and octoploid asparagus can be used for nutrition management by asparagus growers.

One of the strategies for efficiently using agricultural water resources and preserving them is to use absorbent materials such as pumice in soil. The present research aimed to evaluate the effects of different levels of pumice on soil water content and Russian olive seedling growth. For this purpose, an experiment was designed and conducted as a randomized complete block design with four treatments and three replications from 2017 to 2018 in the Khajeh Research Station. Treatments included control (no pumice), and 10%, 20%, and 30% pumice. During the experiment, the average soil moisture content was measured by TDR every 10 days. The growth characteristics of the Russian olive seedlings, including seedling height, collar diameter, and leaf area were measured. Minimum soil water content was recorded for the control treatment and then a significant increase was observed by increasing the use of pumice. In the control treatment, seedling height, collar diameter, and leaf area were 56 cm, 6.2 mm, and 108 cm2, respectively, while in the 30% pumice treatment, the same characteristics were significantly increased to 105 cm, 11.4 mm, and 201 cm2, respectively. So, by increasing the amount of pumice from 0 to 30%, seedling height, collar diameter, and leaf area increased by 87, 84, and 86%, respectively. Therefore, we can conclude that pumice by retaining soil water during the growing season, especially in rainfed conditions, prevents plant water-deficit stress and enhances its growth and development.

Greenhouse vegetable production faces challenges in regions prone to drought and water shortages. Grafting offers opportunities to enhance performance under stress conditions. This study evaluated the growth and biochemical responses of Daphnis tomato grafted onto different rootstocks under different irrigation levels. In a greenhouse experiment, seven Solanaceous rootstocks were used and the plants were subjected to three irrigation regimes (3-day interval as control, and 6-day and 9-day intervals as moderate and severe drought stresses) for four months. Results showed significant effects of irrigation intervals and rootstocks on growth and biochemical characteristics. Increasing irrigation interval led to the reduction in shoot fresh weight (SHFW), root length (RL), and yield. Certain rootstocks (Solanum cheesmaniae, S. lycopersicum var. cerasiforme) outperformed others in SHFW, RL, and yield. Also, rootstocks influenced the accumulation of total phenolic compounds (TPC), total soluble carbohydrates (TSC), and total flavonoid content (TFC). S. lycopersicum var. cerasiforme and S. cheesmaniae showed the lowest levels of these compounds. The interaction of irrigation intervals with rootstocks was significant for root fresh weight, shoot-to-root ratio, and leaf proline content. S. lycopersicum var. cerasiforme and S. cheesmaniae maintained root biomass under severe drought stress, while S. nigrum exhibited efficient resource allocation to the shoots under severe drought stress. Leaf proline content increased under severe drought stress in specific rootstocks. In conclusion, the type of rootstock influenced the growth and biochemical characteristics of the Daphnis tomato under water-deficit stress conditions. S. cheesmaniae, and S. lycopersicum var. cerasiforme demonstrated better growth, while certain rootstocks exhibited higher levels of biochemical compounds. These findings emphasize the importance of rootstock selection for enhancing drought tolerance in tomato cultivation and show the significance of some biochemical compounds in determining the water status of the greenhouse tomato.