23 research outputs found
<em>Kelussiaodoratissima</em> Mozaff.as a rich source of essential fatty acids andphthalides
Abstract Introduction: The present study is the first assessment of the fatty acids of leaf and essential oil compositions of new three habitats of aerial parts of K. odoratissima. Methods: The aerial parts of K. odoratissima from the three habitats were dried. The essential oils were obtained by hydrodistillation for 3 h in a Clevenger-type apparatus, then the analysis of the components was carried out using gas chromatography–mass spectrometry. To study the oil yield and fatty acids, the dried leaves subjected to extraction in hexane by using Soxhlet Apparatus. To analyze fatty acids from the oil fractions by gas chromatography technique, the oil was subjected to transesterification to obtain the fatty acid methyl esters, which, were dissolved in hexane and subjected to GC analysis. Results: According to the results, a total of 43 components, the major constitutes of essential oil compositions were (Z)-Ligustilide (76.45), Unknown-A (4.47), (E)-Ligustilide (2.57), (Z)-Butylidene phthalide (2.37), 5-pentyl cyclohexa-1,3-diene (1.57) and Kessane (0.77) in K. odoratissima. The sixteen fatty acids were separated from the oil (5 yield per 100 g dry matter). Linoleic acid (25.46), α-Linolenic acid (16.66), Palmitic acid (11.92), Oleic acid (9.33), Stearic acid (4.72), Petroselinic acid (2.53), Arachidonic acid (2.51) and Erucic acid (1.76) were major fatty acids. Conclusion: Generally, K. odoratissima is a rich source of essential fatty acids and phthalide derivatives, specially (Z)-ligustilide. This study was presented valuable information about the phytochemical properties, which can be useful for the future researches on the pharmacological effects of K. odoratissima
Barley stem rust resistance genes: structure and function
Rusts are biotrophic pathogens that attack many plant species but are particularly destructive on cereal crops. The stem rusts (caused by Puccinia graminis) have historically caused severe crop losses and continue to threaten production today. Barley (Hordeum vulgare L.) breeders have controlled major stem rust epidemics since the 1940s with a single durable resistance gene Rpg1. As new epidemics have threatened, additional resistance genes were identified to counter new rust races, such as the rpg4/Rpg5 complex locus against races QCCJ and TTKSK. To understand how these genes work, we initiated research to clone and characterize them. The Rpg1 gene encodes a unique protein kinase with dual kinase domains, an active kinase, and a pseudokinase. Function of both domains is essential to confer resistance. The rpg4 and Rpg5 genes are closely linked and function coordinately to confer resistance to several wheat (Triticum aestivum L.) stem rust races, including the race TTKSK (also called Ug99) that threatens the world's barley and wheat crops. The Rpg5 gene encodes typical resistance gene domains NBS, LRR, and protein kinase but is unique in that all three domains reside in a single gene, a previously unknown structure among plant disease resistance genes. The rpg4 gene encodes an actin depolymerizing factor that functions in cytoskeleton rearrangement
Quality assessment of flax advanced breeding lines varying in seed coat color and their potential use in the food and industrial applications
Abstract Background With the increasing consumer awareness of the strong relationship between food and health, flax became a promising functional food due to its bioactive nutraceutical composition. Intra-specific crosses of eight contrasting flax genotypes were performed previously, and within segregating F6 progeny families, we investigated a close-up composition of phytochemicals derived from whole seeds. Results The considerable genetic variation among the flax F6 families suggested that intra-specific hybridization is essential in flax breeding to obtain and broaden genetic variability and largely affirmed the opportunity for selecting promising lines. Also, significant variations in the targeted metabolite contents and antioxidant properties were observed among brown and yellow-seeded families. Notably, brown-seeded families expressed the highest average values of saturated fatty acids, protein, fiber, tocopherol, phenolics, SDG, and SECO lignans. Yellow-seeded families represented the highest average content of unsaturated fatty acids and mucilage. The cultivation year significantly affects flaxseed’s composition and functional properties, presumably due to temperature, humidity, and sunshine time differences. Interestingly, the seeds obtained in warmer conditions were more potent and had more chemical constituents. The favorable genetic correlations among all evaluated traits suggest the possibility of joint genetic selection for several nutritional and phytochemical characteristics in flax. The current study highlights the importance and utilization of 19 top families as their seeds and oil play imperative roles in the pharmaceuticals and food industries. The antioxidant capacity of the seeds showed that families 84B, 23B, 35Y, 95Y, 30B, 88B, and 78B serve as a natural source of dietary antioxidants beneficial to human health. To increase the oxidative stability of the flaxseed oil, the quality evaluation identified some families with low levels of linolenic acid. Conclusions These findings are essential to improving flaxseed’s nutritional quality and therapeutic properties through a bulk breeding program
Determination of Suitable Cultivar and N-topdress Rates in Corn Planted After Wheat Harvest
In order to find suitable cultivar and N-topdress rates in corn planted after wheat harvest, a field experiment was conducted in Isfahan University of Technology Experiment Farm located at Shervedan, Falavarjan in 1994. The experiment design was a split plot with a randomized complete block arrangement and four replications. Main plots were four N-topdress rates (0, 90, 180, and 270 kg/ha) and the subplots were three corn hybrids (S.C.I08, S.C.301, and D.C.370). N-topdress rates had no effect on the stages of plant development (50% emergence, transition, pollination and physiological maturity). Also there were no significant effects on the number of leaves per plant, LAI, plant height and plant dry weight measured at pollination stage for different N-topdress rates. As expected, plant development stages differed among hybrids except that of time until 50% emergence. Differences in the number of leaves per plant, LAI, plant height and dry weight of plant measured at pollination stage were highly significant among hybrids. D.C. 370 had the highest values for all of these characteristics. Dry matter accumulation during growing season increased as the N-topdress rates were increased for the hybrids. Also N-topdress rates x hybrid interaction was significant for biological yield. Grain yield, number of seeds per ear, 100-seed weight and biological yield were affected by N-topdress rates and hybrid. Higher grain yield of D.C. 370 can be attributed to greater number of seeds per ear. The results of this study suggest that D.C. 370 with 90 kg/ha N-topdress rate can be used after wheat harvest in Isfahan
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Abstract The lpsA gene, a late acting gene in the biosynthetic pathway of ergovaline, a suspected causative agent for fescue toxicosis in cattle, has been cloned from Neotyphodium lolii, an endophytic fungus of Lolium perenne. In this study, a similar gene was detected in several strains of endophytic Neotyphodium spp. isolated from grass hosts endogenous to Iran using direct and nested-PCR assays. Except for Bromus tomentellus, most isolates from other hosts contained this gene. The 747-bp PCR products of the local strains had identical restriction patterns for all tested restriction enzymes. Accordingly, sequence analysis of the nested PCR product amplified from the internal segment of 747-bp band, showed 99% similarity with the corresponding region of the lpsA gene of N. lolii. It therefore appears that prevalence of the lpsA gene with its conserved nature among Neotyphodium isolates is mainly host dependent
Potentials of synthetic hexaploid wheats to improve drought tolerance
Abstract Synthetic hexaploid wheat-derived lines (SHW-DL) offers new hope for breeders to restore genes lost during the evolutionary bottleneck. The study of adaptability, variation, and the possibility of selection in SHW-DL for drought tolerance is poorly understood in arid environments. The potential of 184 SHW-DL and their variation for agro-morphological traits were assessed under normal and water stress conditions for 2 years. The mean values of grain yield (YLD) varied from 683.9 g/m2 (water stress) to 992.1 g/m2 (normal conditions). Grain yield decreased by 64 and 71% under water stress in the two growing seasons. High genotypic variation was found for measured traits and drought tolerance. Heritability ranged from 19 (harvest index) to 47% (spike length), whereas grain yield indicated a moderate heritability (32%). Using the assessment of the interrelationship of traits, hectoliter (a quality trait) was correlated with drought tolerance and stability indices. Therefore, it can be considered as an important trait to select drought tolerant genotypes. In the following, the priority of yield components entering the regression model was different in two moisture conditions suggesting different strategies in indirect selection programs to improve yield. Spike m−2 and grain spike−1 indirectly and negatively affected yield through thousand-grain weight (TGW) under normal and water stress conditions, respectively. Furthermore, SHW-DL compared to ordinary wheat were significantly superior in terms of early maturity, dwarfing, yield, TGW, stem diameter, and harvest index. Overall, our findings suggest that SHW-DL are a valuable source for improving wheat yield and drought tolerance, and indirect selection might be possible to improve these complex traits
Kelussia odoratissima Mozaff. as a rich source of essential fatty acids and phthalides
Introduction: The present study is the first assessment of the fatty acids of leaf and essential oil compositions of new three habitats of aerial parts of K. odoratissima. Methods: The aerial parts of K. odoratissima from the three habitats were dried. The essential oils were obtained by hydrodistillation for 3 h in a Clevenger-type apparatus, then the analysis of the components was carried out using gas chromatography–mass spectrometry. To study the oil yield and fatty acids, the dried leaves subjected to extraction in hexane by using Soxhlet Apparatus. To analyze fatty acids from the oil fractions by gas chromatography technique, the oil was subjected to transesterification to obtain the fatty acid methyl esters, which, were dissolved in hexane and subjected to GC analysis. Results: According to the results, a total of 43 components, the major constitutes of essential oil compositions were (Z)-Ligustilide (76.45%), Unknown-A (4.47%), (E)-Ligustilide (2.57%), (Z)-Butylidene phthalide (2.37%), 5-pentyl cyclohexa-1,3-diene (1.57%) and Kessane (0.77%) in K. odoratissima. The sixteen fatty acids were separated from the oil (5% yield per 100 g dry matter). Linoleic acid (25.46%), α-Linolenic acid (16.66%), Palmitic acid (11.92%), Oleic acid (9.33%), Stearic acid (4.72%), Petroselinic acid (2.53%), Arachidonic acid (2.51%) and Erucic acid (1.76%) were major fatty acids. Conclusion: Generally, K. odoratissima is a rich source of essential fatty acids and phthalide derivatives, specially (Z)-ligustilide. This study was presented valuable information about the phytochemical properties, which can be useful for the future researches on the pharmacological effects of K. odoratissima
Association analysis revealed loci linked to post-drought recovery and traits related to persistence of smooth bromegrass (Bromus inermis)
Association analysis has been proven as a powerful tool for the genetic dissection of complex traits. This study was conducted to identify association of recovery, persistence, and summer dormancy with sequence related amplified polymorphism (SRAP) markers in 36 smooth bromegrass genotypes under two moisture conditions and find stable associations. In this study, a diverse panel of polycross-derived progenies of smooth bromegrass was phenotyped under normal and water deficit regimes for three consecutive years. Under water deficit, dry matter yield of cut 1 was approximately reduced by 36, 39, and 37% during 2013, 2014, and 2015, respectively, compared with the normal regime. For dry matter yield of cut 2, these reductions were approximately 38, 60, and 56% in the same three consecutive years relative to normal regime. Moreover, water deficit decreased the RY and PER of the genotypes by 35 and 28%, respectively. Thirty primer combinations were screened by polymerase chain reaction (PCR). From these, 541 polymorphic bands were developed and subjected to association analysis using the mixed linear model (MLM). Population structure analysis identified five main subpopulations possessing significant genetic differences. Association analysis identified 69 and 46 marker-trait associations under normal and water deficit regimes, respectively. Some of these markers were associated with more than one trait; which can be attributed to pleiotropic effects or tightly linked genes affecting several traits. In normal and water-deficit regimes, these markers could potentially be incorporated into marker-assisted selection and targeted trait introgression for the improvement of drought tolerance of smooth bromegrass
Effects of Occurrence of Drought Stress in Maternal Environment on Cardinal Temperatures and Germination Responses of Carthamus Species
Safflower (Carthamustinctorius L.) is one of the oldest domesticated crops, mainly grown as an oilseed in the arid and semiarid regions of the world. This study was conducted to investigate the Cardinal temperatures and to identify the effects of occurrence of drought stress in maternal environment on seed germination aspects of some Carthamus species according to a completely randomized design in 2014. To accomplish this, seeds of 13 genotypes from C. tinctorius, C. palaestinus, C. oxyacanthus, C. glaucus and C. lanatus were used which had been harvested from plants grown at normal and drought stress conditions. Seeds were subjected to 9 fixed temperatures (5, 10, 15, 20, 25, 30, 35, 40 and 45°C) for germination in the growth chamber according to a factorial experiment. Results showed that the effects of genotype, species, temperature, pretreatment drought stress and some of their interactions were significant for certain germination characteristics at 0.05% probability level. Significant reductions occurred in the germination rate of seeds at temperatures below 10°C and above 30°C. Although there were significant differences in percent of seed germination among species, seeds harvested from drought stressed plants were not significantly different from the ones harvested from non-stressed plants in terms of cardinal temperatures. Hence, it is more likely that cardinal temperatures will not cause difficulties in the case of inter-specific breeding programs for drought tolerant safflower cultivar development
Evaluation of Drought Tolerance Indices and Physiological Traits in Cultivated and Wild Barley
Drought stress is one the most limiting factors for crop production worldwide. The wide ecological and environmental dispersion of crop wild relatives, generates a high potential of their adaptive diversity to abiotic stresses such as drought. In this study 21 (including 10 cultivated and 11 wild barley (Hordeumvulgaressp. spontaneum))genotypes were evaluated under three soil water conditions for grain yield, drought tolerance indices (STI and YSI) and some physiological traits during two growing seasons(2012-2013 and 2013-12014). High genetic variation was observed for grain yield and STI and YSI indices between and within cultivated and wild barley groups of genotypes. Differences were also observed between the genotypes for physiological traits. Different responses of the genotypes to different levels of drought stress were also observed for all of the measured traits. The high-yielding varieties were more tolerant based on STI index, but the average of yield stability under stressed conditions (YSI) was significantly higher in the wild barley group of genotypes comparing to cultivated ones, indicating a high level of drought tolerance in wild genotypes. Among physiological traits, significant differences were observed for relative water content and proline content between cultivated and wild barley genotypes, showing the importance of these two traits in different response of the two genotypic groups to drought stress. The STI and YSI indices identified the most drought tolerant genotypes at different soil moisture levels. The tolerant genotypes were mostly belonged to wild barley. These genotypes can be used in breeding programs by crossing them with high-yielding varieties such as Reihan 03 for increasing drought tolerance of cultivated barley