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81.
The improvement of sugar-related factors is associated with root traits in sugar beet. The objectives of the present study were to assess variations of sugar- and root yield (RY)-related traits and to estimate general (GCA) and specific (SCA) combining abilities of several lines, testers and hybrids under various environmental conditions. A line × tester mating design was used to develop 28 hybrids from seven lines × four testers. Presently, root- and sugar-related traits were recorded in parental lines, hybrids and five local ('Pars', 'Torbat' and 'Ekbatan') and international ('Kermit' and 'Tous') check varieties in the eight combinations of location and growing season. Mean RY and sugar yield (SY) were 44.81 t/ha and 7.57 t/ha, respectively. Genotypes tested had 16.91% sugar content (SC) and 13.64% white sugar content (WSC) across trials. No one genotype was found to have high levels for all traits, but several had above mean sugar-related or RY traits. L7T2 as the best hybrid for RY and SY yielded 37.0% and 34.4% more than the checks’ mean, whereas ratios for the best hybrid (L7T4) for SC and WSC were 8.2% and 4.3%, respectively. Additive variance was significant for all traits, whereas dominance component was only significant for RY. Several parental lines had stable GCA effects with respect to direction and magnitude for WSC, RY and SC in environments. L7 and T2 for RY and SY and L3 and T4 for SC and WSC were identified as the best combiners with high GCA effects, and their use might increase favourable alleles in further breeding programmes for traits tested. Estimated heritability for the combined environments was lower for sugar-related traits (54.01%–59.39%) compared with those for RY traits (73.68%–74.21%). Overall, given heritability and additive variances estimated the identification of environmentally stable GCA and SCA effects and might help to increase efficiency of selection of superior cultivars with respect to sugar traits. 相似文献
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84.
Maryam Ebrahimiyan Mohammad Mahdi Majidi Aghafakhr Mirlohi Abbas Noroozi 《Euphytica》2013,190(3):401-414
The physiological basis of genetic variation in drought response and its association with yield and related indices is not clear in tall fescue. In this study thirty genotypes of tall fescue (Festuca arundinacea Schreb.) were sampled from a polycross population and evaluated under two levels of irrigation in 2010 (normal and intense stress) and 2011 (normal and mild stress). Physiological traits including relative water content (RWC), total chlorophyll (TChl), chlorophyll a (Chla), chlorophyll b (Chlb), Chla/Chlb, carotenoids (Car), TChl/Car and proline content along with forage yield, agro-morpholgical traits and selection indices (stress tolerance index, STI and drought susceptibility index, DSI) were studied. Large variation and moderate to high heritability was estimated for most of the studied traits. Intense drought condition decreased chlorophyll content while mild stress significantly increased it. In the other hand intense drought stress increased Chla/b while mild stress didn’t change it. Under mild drought stress condition STI was positively correlated with RWC while under intense drought stress condition STI was positively correlated with chlorophyll content. Although proline content was significantly increased in both intense and mild drought stress conditions, no relationship was found between proline accumulation with forage yield and STI. Applications of principle component analysis for screening suitable genotypes are also discussed. 相似文献
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86.
Surur Khorramdel Alireza Koocheki Mahdi Nassiri Mahallati Reza Ghorbani 《Journal of plant nutrition》2016,39(14):2015-2024
The purposes of this study were evaluate the effects of biofertilizers inoculation on growth indices, yield and radiation use efficiency (RUE) in black cumin under Mashhad climatic conditions. This field experiment was carried out based on a randomized complete block design with three replications. This experiment was performed at Agricultural Research Station, Ferdowsi University of Mashhad, Iran, during two growing seasons 2007–2008 and 2008–2009. Treatments were (A) Azotobacter paspali, (B) Azospirillum brasilense, (C) Rhizophagus irregularis, A + C, B + C, A + B, A + B + C and control. In all treatments, except control, 100 g of seeds were inoculated with15 mg of each biofertilizer. Results indicated that leaf area index (LAI) and accumulative dry matter (DM) showed an increasing trend up to 1863°Cd and a short declining trend afterwards. The relation between accumulative DM and absorbed photosynthesis active radiation (PARa) was linear. Radiation use efficiency (RUE) fluctuated from 0.55 gMJ?1 (control) to 0.89 gMJ?1 (B+C). Inoculation with biofertilizers enhanced root development and hence availability of moisture and nutrients, particularly nitrogen and phosphorus. Since these ecological fertilizers produce many growth regulators for the plant which promote LAI and accumulative DM and therefore yield, PARa and RUE enhanced. 相似文献
87.
Maryam Rezashateri Sayed Jamaleddin Khajeddin Mohammad Mahdi Majidi Sayed Hamid Matinkhah 《Archives of Agronomy and Soil Science》2017,63(7):984-997
The effects of super absorbent polymers (SAPs) on growth characteristics and seedlings survival of Artemisia sieberi (under two soil textures, three irrigation levels and seven hydrogel compositions with three replications) were investigated. The studied traits were shoot height, shoot dry weight, root dry weight, ratio of root/shoot, root length, root perimeter, root area and root volume. SAPs successfully enhanced growth capability of A. sieberi in two soil textures compared to the controls. Ideally, 5 g kg?1 Aquasorb? (SNF Company, France) with 100% irrigation and 10 g kg?1 Stockosorb® (Evonik Corporation, Germany) with 75% irrigation in a sandy loam texture and 10 g kg?1 Boloorab A? (Boloorab Company, Iran) with 75% irrigation in a loamy texture significantly affected all traits, resulting in 100% survival for A. sieberi seedlings. Aquasorb? and Stockosorb® showed the best results in the sandy loam texture and preferable outputs were obtained by Boloorab A? application in the loamy texture. In other words, because of the basic differentiation among soils in terms of mineralogy, temperature and moisture content, different SAPs should be applied. Production of dense root network and root aggregation stimulated by SAPs increased root contact with moisture. Therefore, improving the growth and survival of the plants is accessible using SAPs under water stress condition. 相似文献
88.
ABSTRACTThe effects of combined infrared-vacuum drying parameters, including infrared power (300–400 W), pressure (5–25 kPa) and time (0–140 min) on the drying kinetics of grapefruit slices were investigated. Both the infrared lamp power and vacuum pressure influenced the drying time of grapefruit slices. The regression results showed that the quadratic model satisfactorily described the drying behavior with highest R and lowest SE values. The effective moisture diffusivity increases as power increases and range between 5.83 × 10–10 and 2.13 × 10–9 m2/s. The color scale parameters, including redness (a*), yellowness (b*) and lightness (L*) values of dried grapefruit slices increased during drying. The rise in infrared power has a negative effect on the color change intensity (?E) and with increasing in infrared radiation power it was increased. Different kinetic models were used to fit the experimental data and the results revealed that the power model was the most suitable to describe the ?E. 相似文献
89.
Shirani D Nassiri SM Aldavood SJ Seddigh HS Fathi E 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(4):389-393
Dysplastic features of erythroid and megakaryocytic lineages were observed in a cat with acute erythroid leukemia. We demonstrated that flow cytometry analysis of the expression of glycophorin A and CD71 by neoplastic cells can be helpful in the diagnosis of this type of feline leukemia. 相似文献
90.
Fatemeh Saeidnia Mohammad Mahdi Majidi Aghafakhr Mirlohi Marziye Manafi 《Plant Breeding》2017,136(2):270-278
This study was conducted to evaluate drought tolerance and persistence in a germplasm of smooth bromegrass and association of forage productivity with different traits. Thirty‐six genotypes of smooth bromegrass were clonally propagated and evaluated under two soil moisture environments for three years (2013–2015). High genotypic variation was observed among genotypes for all the measured traits. Drought stress decreased mean values for traits related to productivity. Also, the long‐term stress for three years reduced the persistence of plants. Results indicated that indirect selection based on components of forage yield, which had high heritability and high correlation with yield, would be more effective to improve drought tolerance in this germplasm. The results of principal component analysis showed that there was a negative relationship between phenological traits with the persistence‐related traits and yield production. This suggests that selection for earliness may indirectly promote persistent genotypes. The results showed that some Hungarian genotypes are valuable gene sources for persistence. The most persistent genotypes from both groups (Iranian and foreign) were identified using the biplot method. These genotypes may be useful for the development of populations for future studies. 相似文献