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31.
In cereals, chromosome doubling of microspore-derived haploid plants is a critical step in producing doubled haploid plants.
This investigation was undertaken to study the effect of incorporation of colchicine in the induction medium for anther culture,
and the effect of colchicine on anther culture-derived plants of triticale grown under controlled greenhouse conditions. In
the latter case, chromosome doubling of adult sterile plants derived from anther culture of fourteen triticale populations
was attempted, where androgenetic plants with non-dehiscent anthers were cloned and subjected to the colchicine treatment,
and then grown with the aid of hydroponics. The hydroponic system provided optimal conditions for recovery of the affected
haploids from the toxic effects of colchicine treatment and all colchicine-treated plants survived. A topcross-F1 (TC1F1) population with timopheevii cytoplasm produced the highest percentage of plants with seed-set either due to chromosome doubling
by colchicine (98%) or spontaneous doubling of chromosome number (15%). Colchicine-treated anthers performed inferior than
control in both induction and regeneration phases. One of the key observation of this study was the reversal from reproductive
stage back to the vegetative stage which in turn enabled further cloning of haploid plants under hydroponic conditions once
they were identified as sterile. The one hundred percent survival rate of in vitro-derived plants, 100% survival rate of colchicine treated haploid plants and the high chromosome doubling success rate (X
= 82.3) observed in this study imply that a temperature-controlled greenhouse with an hydroponic system provides an efficient
environment for inducing chromosome doubling of haploid plants in cereals.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
32.
One myrsinol-type diterpene ester (1) isolated from Euphorbia decipiens was evaluated for analgesic activity in the acetic acid induced writhing test in mice. Different dose (5-20 mg/kg i.p.) of the compound showed significant antinociceptive activity, which was comparable to standard analgesic drugs, aspirin and ibuprofen (100 mg/kg i.p.). 相似文献
33.
Haitham Sayed Gunter Backes Hamed Kayyal Amor Yahyaoui Salvatore Ceccarelli Stefania Grando Ahmad Jahoor Michael Baum 《Euphytica》2004,135(2):225-228
A partial genetic linkage map was constructed on 71 doubled-haploid lines derived from a cross between the barley lines Tadmor
and WI2291 with 181 molecular markers. The segregating population was used to detect markers linked to the gene Mlg conferring resistance to powdery mildew (Erysiphe graminis f. sp. hordei) and to genes for quantitative resistance to scald (Rhynchosporium secalis). The gene Mlg on chromosome 4H was flanked by two AFLP markers at a distance of 2.0 and 2.4 cM, respectively. QTLs for resistance to scald
were detected on chromosomes 2H and 3H. This association of molecular markers with qualitative and quantitative disease resistance
loci represents a valuable starting-point for marker-assisted selection.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
34.
Dynamic oxygen mapping in the root zone by fluorescence dye imaging combined with neutron radiography 总被引:1,自引:0,他引:1
Nicole Rudolph Hanna G. Esser Andrea Carminati Ahmad B. Moradi André Hilger Nikolay Kardjilov Stefan Nagl Sascha E. Oswald 《Journal of Soils and Sediments》2012,12(1):63-74
Purpose
The rooted zone of a soil, more precisely the rhizosphere, is a very dynamic system. Some of the key processes are water uptake and root respiration. We have developed a novel method for measuring the real-time distribution of water and oxygen concentration in the rhizosphere as a biogeochemical interface in soil. This enables understanding where and when roots are active in respect to root respiration and water uptake and how the soil responds to it. 相似文献35.
Barkha SHARMA Kailash Chand KUMAWAT Shalini TIWARI Ajay KUMAR Rouf Ahmad DAR Ummed SINGH Massimiliano CARDINALE 《土壤圈》2023,33(4):534-555
Silicon (Si) is the second most abundant element in the Earth’s crust and has numerous roles in both soils and plants, although it is inaccessible to plants in its native state (insoluble silicate minerals). This inaccessibility can lead to insufficiency, which induces anomalies in plant growth and development.Specifically, Si alleviates various biotic and abiotic stresses in plants by enhancing tolerance mechanisms at different stages of uptake/deposition as a monosilicic acid. Exclusive utiliz... 相似文献
36.
Summary Eight grain pearl millet (2n=14) accessions were crossed as male to hexaploid spring wheat cv. Fukuho (2n=6x=42). An average of 80% wheat pistils showed pearl millet pollen tube entry in the ovules, compared to 56% in wheat x maize cv. Seneca 60 cross. Of the 15 embryos, obtained through in vitro immature seed culture from wheat x pearl millet crosses, 3 plantlets were produced and grown to maturity. These three were of the somatic chromosome constitution 2n=42, 21 and 22, respectively. Haploid wheat plant (2n=21) apparently originated from pearl millet chromosome elimination during embryogenesis. The 22 chromosome plant had retained a single pearl millet chromosome at tillering stage, but this chromosome was eliminated from pollen mother cells prior to and also during gamete formation. The significance and potential uses of this wide cross is discussed. 相似文献
37.
Roghayeh Shahriaripour Ahmad Tajabadipour Isa Esfandiarpoor Vahid Mozafary 《Journal of plant nutrition》2019,42(11-12):1277-1282
Developing a fast and reliable soil testing method is critical for improving soil testing efficiency and ensuring reliable fertilizer recommendation. The objectives of this study were to evaluate sodium ethylene diamine tetra acetic acid (Na2-EDTA) as a replacement for ammonium bicarbonate-diethylenetriaminepentaacetic acid (AB-DTPA) to extract phosphorus (P) to determinate the relationships between extractable P and its uptake by crop in calcareous soils. Na2-EDTA and AB-DTPA was compared by the amounts of extracted P by analyzing soil samples collected from agricultural production areas. There were significant correlations between Na2-EDTA and AB-DTPA for soil test P based on soils collected from the agricultural field. Soil test P by both extractants was significantly correlated with plant P concentration. Na2-EDTA was identified as an alternate improved extraction method instead of AB-DTPA in calcareous soils based on this study. However, more work will be needed to identify the correlation of the two extractants and crop responses under a field condition. 相似文献
38.
Shankar Reddy Kolle T. H. Shankarappa Basir Ahmad Rahimi M. V. Satish 《Journal Of Agricultural & Food Information》2019,20(1):25-38
A review of publications on “Strawberry” was done by using the Scopus database for the period 1960–2016. A total of 10,400 articles were found in the database and analyzed using a variety of measures. Results show that publication increased exponentially from 1960 to 2016. Multiple authors are collaborating in strawberry research. Acta Horticulturae was the most productive journal. The United States of America was the most productive country. The greatest portion of the research was concerned with medicinal benefits of strawberries to humans. This work will be useful to researchers in identifying trends in strawberry research. 相似文献
39.
Rashid Ahmad 《Water, air, and soil pollution》2005,163(1-4):169-183
Cr(III) ions sorption onto sawdust of spruce (Picea smithiana) has been studied thoroughly using radiotracer technique. Maximum sorption (94%) of Cr(III) ions (8.98×10?5 M) onto sorbent surface is achieved from deionized water in 20 min agitation time using 200 mg of sawdust. The sorption data followed the Freundlich, Dubinin-Radushkevich (D-R) and Langmuir isotherms. Freundlich constants l/n = 0.86 ± 0.07 and C e = 85.0 ± 25.8 mmole g?1 have been estimated. Sorption capacity, X m = 0.82± 0.3 mmole g?1, β = ?0.00356± 0.00017 kJ2 mole?2 and energy, E = 11.9± 0.3 kJ mole?1 have been evaluated using D-R isotherm. The Langmuir constants Q = 5.8± 0.2 μmole g?1 and b = (7.4± 0.5)×104 dm3 mole?1 have been calculated. The variation of sorption with temperature yields thermodynamic parameters Δ H = ?11.6± 0.3 kJ mole?1, Δ S = ?16.2± 0.9 J mole?1 K?1 and Δ G = ?6.8± 0.3 kJ mole?1 at 298 K. The negative value of enthalpy and free energy reflect the exothermic and spontaneous nature of sorption respectively. Among the anions studied oxalate, citrate, carbonate and borate have reduced the sorption. The cations Y(III), Ce(II) and Ca(II) suppressed sorption. The sawdust column can be used to separate Cr(III) ion from Cs(I), I(I),Tc (VII) and Se (IV). 相似文献
40.
Exogenous application of thiamine (vitamin B1) during imbibition improved germination and seedling development of bean (Phaseolus vulgaris L. cv. Lasso) seeds, which were exposed to soaking injury by submergence. Leaching of the vitamin into the incubation medium was not increased in submerged seeds. However, translocation of the thiamine reserves from the cotyledons to the seedling axis was reduced in response to soaking injury. After exogenous application of free thiamine to the seeds, thiaminedi-phosphate (TDP), which is the physiologically active coenzyme form of thiamine, accumulated in the seedling axis of submerged seeds, suggesting an increased demand for thiamine-dependent metabolic reactions in these tissues. Limited oxygen supply of the seeds during the soaking period induces a shift from respiration to fermentation of carbohydrates. Neither thiamine-dependent ethanolic fermentation, nor ATP production or adenylate energy charge (AEC) of the seedling axis were affected by exogenous thiamine application, suggesting that there is no limitation of thiamine-dependent reactions in the energy metabolism of the seedlings. Thus the physiological mechanisms improving germination and seedling development of submerged seeds in response to thiamine seed treatment are still not clear. 相似文献