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991.
高粱314A、13A与苏丹草杂种F1代的农艺特性及细胞学分析 总被引:8,自引:0,他引:8
分析了雄性不育系高粱314A、13A与3种苏丹草杂交组合F1代的生育、株高、穗型、分蘖性、产量、光合性能及细胞遗传学等特性.结果表明各杂交种F1植株高大,平均株高343~369 cm,穗型呈双亲中间型,种子活秆成熟,生育期130~137 d,分蘖性强,单株平均分蘖数6.3~9.0个,花粉可育率91%以上,自然结实率63.88%~67.79%;F1鲜草产量比各自父本苏丹草增加16.17%~32.73%,种子产量增加41.40%~52.97%,杂种超亲优势19.29%~48.68%,茎叶比3.05~3.66;F1净光合速率、气孔导度、胞间CO2浓度均明显超过其各自亲本,CO2固定能力强;F1代PMCMⅠ染色体均能正常配对,平均构型为2n=2x=20(10Ⅱ),但棒状二价体频率明显高于其双亲,原亲本间的遗传组成仍存在着一定的差异;试验证明母本314A、13A的雄不育发生在减数分裂后的小孢子形成期. 相似文献
992.
Heba I. Mohamed Eman M. Fawzi Abdul Basit Kaleemullah Rafiq Lone Mahmoud R. Sofy 《Phyton》2022,91(7):1303-1325
After wheat, rice, maize, and barley, sorghum is the fifth most widely grown cereal on the planet. Due to its high
production, drought resistance, and heat tolerance, this crop is replacing maize in some areas. Sorghum is available in a variety of colors, including cream, lemon-yellow, red, and even black. The principal grain anatomical
components are pericarp, germ or embryo and endosperm. This review provides an overview of key sorghum
grain components, including starches, fiber, proteins, lipids, and vitamins. Also, we summarized phenolic compounds, flavonoids, tannins, carotenoids, vitamin E, amines, Policosanols and Phytosterols in sorghum grains.
Sorghum is used to manufacture bread and porridge, and it provides a significant source of energy and nutrition
for humans; sorghum is extensively farmed for animal feed. However, because the natural components in sorghum are useful in the development of healthy and functional foods, sorghum farming for both biofuel production and human consumption is gaining popularity. Pigmented sorghum grain is high in antioxidants such as
polyphenols, primarily tannins, which have a variety of health benefits, including antiproliferative properties
linked to the prevention of certain cancers, antioxidant activities linked to the prevention of diseases linked to
oxidative stress, and anti-inflammatory effects, as well as improving glucose metabolism. Because these chemicals
cannot be assimilated, their application in the food business has been limited, as sorghum is regarded as a lownutritional grain due to the presence of anti-nutritional components such as strong tannins, which form complexes with proteins and iron, limiting their digestibility. This review aims to show the utilization of sorghum
as a source of bioactive chemicals and the value they bestow on human health due to the general biological potential it possesses. 相似文献
993.
Is an egg-killer present in rice? 总被引:7,自引:0,他引:7
Y. Sano 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(8):1038-1042
The genetic model for hybrid sterility that an allelic interaction at the S
5 locus induces the abortion of megaspores has been proposed as partial clarification of the wide compatibility in Asian rice cultivars; this model predicts the presence of an egg-killer. The present study was carried out in order to confirm that the proposed S
5
i
allele acts as an egg-killer against its counterpart, the S
5
j
allele, in the Indica-Japonica hybrid. A conspicuous feature of an egg-killer is the high rate of its transmission into the progeny through the egg. Backcrossing experiments were conducted using the Indica-Japonica hybrid in which the S
5
i
and S
5
j
alleles were assumed to be involved. Although an egg-killer was easily identified by these backcross experiments, it was not detected in the Indica-Japonica hybrid, which suggests that the proposed genetic mechanism for hybrid sterility in Asian rice should be viewed with caution. 相似文献
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997.
Igor A Topol Raul E Cachau Alexander V Nemukhin Bella L Grigorenko Stanley K Burt 《Biochimica et Biophysica Acta - Proteins and Proteomics》2004,1700(1):125-136
We present results of the modeling for the hydrolysis reaction of guanosine triphosphate (GTP) in the RAS–GAP protein complex using essentially ab initio quantum chemistry methods. One of the approaches considers a supermolecular cluster composed of 150 atoms at a consistent quantum level. Another is a hybrid QM/MM method based on the effective fragment potential technique, which describes interactions between quantum and molecular mechanical subsystems at the ab initio level of the theory. Our results show that the GTP hydrolysis in the RAS–GAP protein complex can be modeled by a substrate-assisted catalytic mechanism. We can locate a configuration on the top of the barrier corresponding to the transition state of the hydrolysis reaction such that the straightforward descents from this point lead either to reactants GTP+H2O or to products guanosine diphosphate (GDP)+H2PO4?. However, in all calculations such a single-step process is characterized by an activation barrier that is too high. Another possibility is a two-step reaction consistent with formation of an intermediate. Here the Pγ-O(Pβ) bond is already broken, but the lytic water molecule is still in the pre-reactive state. We present arguments favoring the assumption that the first step of the GTP hydrolysis reaction in the RAS–GAP protein complex may be assigned to the breaking of the Pγ-O(Pβ) bond prior to the creation of the inorganic phosphate. 相似文献
998.
Chrysovalantou Antonopoulou Kortessa Dimassi Ioannis Therios Christos Chatzissavvidis Ioannis Papadakis 《Acta Physiologiae Plantarum》2007,29(6):559-561
The objective of this research was to study the effect of the chelated form of the iron salt of ethylenediamine di-o-hydroxyphenylacetic acid (Fe-EDDHA) (6% Fe) on in vitro rooting of the rootstock GF-677. The iron salt of ethylenediamine
tetraacetic acid (Fe-EDTA) (12% Fe) of the MS basic medium was replaced by Fe-EDDHA, which was applied in three concentrations:
93.5, 187.0 and 280 mg l−1 (5.6, 11.2 and 16.8 mg l−1 Fe, respectively). For each treatment of Fe-EDDHA, the effect of ascorbic acid added in four concentrations (0, 0.1, 1.0
and 10 mg l−1) was studied. After 4 weeks of culture, the explants growing on the medium with 280 mg l−1 Fe-EDDHA gave the best rooting results. Regarding ascorbic acid, no clear stimulating effect on rooting was found. 相似文献
999.
Amber Welk Friedrich Recknagel Hongqing Cao Wai-Sum Chan Anita Talib 《Ecological Informatics》2008,3(1):46-54
In the context of this study two concepts were applied for the development of rule-based agents of algal populations: (1) rule discovery by means of a hybrid evolutionary algorithms (HEA) and rigorous k-fold cross-validation, and (2) rule generalisation by means of merged time-series data of lakes belonging to the same lake category. The rule-based agents developed during this study proved to be both explanatory and predictive. It has been demonstrated that the interpretation of the rules can be brought into the context of empirical and causal knowledge on chlorophyll-a dynamics as well as population dynamics of Microcystis and Oscillatoria under specific water quality conditions. The k-fold cross-validation of the agents based on measured data of each year of similar lakes revealed good forecasting accuracy resulting in r2 values ranging between 0.39 and 0.63. 相似文献
1000.
Two new Sicilian stick-insects have been discovered within the genus Bacillus. Evidence concerning the subspecific differentiation of Bacillus grandii benazzii and the hybrid constitution of B. rossius-grandii benazzii by means of allozyme analysis is given, and is consistent with morphological and karyological data on the differentiation of these two north-west Sicilian morphs from south-eastern B. g. grandii and B. whitei. B. g. benazzii is more polymorphic than B. g. grandii and B. rossius-g. benazzii embodies its genetic variability, thus differing sharply from the south-eastern parallel hybrid B. whitei ( = B. rossius × B. g. grandii). Reproductive mechanisms also appear to be different in the two interspecific hybrids, involving parthenogenesis in the latter and hybridogenesis in the former. Finally, the phyletic relationships among all Sicilian Bacillus taxa are summarized in a revised scheme, which also takes into account new evidence that B. atticus has contributed to hybrid constitution of the triploid B. lynceorum. 相似文献