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991.
不同培养基及其元素组成对西洋参愈伤组织悬浮培养物生长和皂苷含量的影响 总被引:5,自引:1,他引:5
对MS、67-V和FOX 3种基本基质对西洋参(Panax quinquefolium Linn.)愈伤组织悬浮培养物生长和皂苷含量的影响进行了比较。在3种基本基质中,培养物的鲜重和干重增加量差异不大,而皂苷含量和产量差异较大,其中MS较高,FOX次之,67-V最低。探讨了MS基质中,KNO3、CaCl2和MgO4对培养物生长和皂苷含量的影响。KNO3浓度在237.5mg/L时有利于培养物生长,而浓度在1900mg/L时有利于皂苷合成;CaO2浓度在55.35mg/L时有利于培养物生长,而浓度在332.1mg/L时有利于皂苷合成;MgSO4浓度为92.50mg/L时培养物生长最好,皂苷产量也最高。 相似文献
992.
Kapil Gupta Sujit Kumar Mishra Shubhra Gupta Saurabh Pandey Jogeswar Panigrahi Shabir Hussain Wani 《Phyton》2021,90(5):1339-1362
Soybean (Glycine max (L.) Merr) is an agro-economic crop growing across the world to cater nutrition for both
human and animal feed due to the high oil and protein content in its edible seeds. The genes and QTLs associated
with important agronomic traits in this crop have already been identified and validated for soybean cyst nematode
(SCN), Phytophthora root and stem rot, Pythium root rot and aphid resistance, seed quality, nutrient values, and
also employed for genetic improvement in soybean. In the last decade, micro RNAs (miRNAs) have been considered the effector molecules, so the detection and characterization of novel miRNAs in soybean have been taken
up by several workers. The advancement in the strategy of sequencing and tools of bioinformatics during last
decade has contributed to the discovery of many soybean miRNAs, thus miRNA can be used as a tool in molecular
breeding studies, and this has opened new vistas for miRNA mediated genetic improvement of soybean to augment
crop productivity as well as nutritional quality. This review addresses the current state of understanding of miRNAmediated stress responses, nutrient acquisition, plant development and crop production processes in soybean. 相似文献
993.
Mohammad Mousa Al-Ansari A. Steevensz N. Al-Aasm K.E. Taylor J.K. Bewtra N. Biswas 《Enzyme and microbial technology》2009,45(4):253-260
Crude soybean peroxidase (SBP), isolated from soybean seed coats (hulls), catalyzes the oxidative polymerization of hazardous aqueous phenylenediamines and benzenediols in the presence of hydrogen peroxide. Experiments were conducted to investigate the optimum operating conditions including pH, hydrogen peroxide-to-substrate concentration ratio and the minimum SBP concentration required to achieve at least 95% conversion of these pollutants in synthetic wastewaters. The substrate conversion and hydrogen peroxide consumption were monitored over the period of the reactions. Polyethylene glycol (PEG) was ineffective as an additive in enhancing the conversion efficiency. The enzymatically generated polymeric products from phenylenediamines could be removed with the aid of a surfactant, sodium dodecyl sulfate (SDS), whereas the polyvalent metal cation salt, aluminum sulfate (alum), was able to remove the products from benzenediols, except hydroquinone. Enzyme-catalyzed polymerization with SBP and subsequent removal of the polymeric products generated can provide an alternative means to the conventional methods for treating many aromatic wastewater pollutants, including the title compounds. 相似文献
994.
大豆异黄酮的微生物转化 总被引:9,自引:0,他引:9
大豆异黄酮是近年来发现的具有多种生物学活性的大豆营养成分。综述了微生物对大豆异黄酮的转化过程,对大豆异黄酮的生物利用和营养成分的影响,指出在富含大豆异黄酮类制品生产过程中合理利用微生物活动的重要意义和可能途径。 相似文献
995.
996.
997.
Haddish Melakeberhan 《Plant and Soil》2007,301(1-2):111-121
The soybean cyst nematode (SCN, Heterodera glycines) continues to spread in soils receiving many forms of soil nutrient amendments, including small amounts of N although applied
with no particular reference to SCN and/or other stress inducing factors. The objective of this 2-year study was to test if
standard at-planting application of 112.09 kg−1 ha−1 of 06–15–40 (N–P–K) containing urea (+N), or 0–15–40 (N–P–K) (−N) or a no fertiliser check (0) affect yield of SCN resistant
(‘Jack’) and two susceptible (‘CX 252’ and ‘Kenwood-94’) soybean cultivars under high and low SCN and other soil abiotic stresses.
Yield was higher under low compared to high stress during both years, with Jack producing the highest yield and Kenwood-94
the lowest. While not statistically significant, +N tended to decrease nodulation and increase yield under low stress in all
cultivars. Nodulation was correlated positively with yield and negatively with daily nematode population density (DNPD), suggesting
potential problems for N supply under nematode infestation. The susceptible cultivars accumulated significantly more leaf
Ca and Mg than Jack, which was more pronounced in the presence of high rather than low stress, confirming known responses
to stress. At high stress, only CX 252 showed a yield increase in response to N treatment, suggesting possible physiological
adaptation mechanisms. Future research that account for the relationships amongst DNPD, frequency of sampling, and host response
to better understand confounding factors and to conclusively prove or disprove any benefits from supplementary N under SCN
infestation are discussed. 相似文献
998.
999.
Effects of carbonized and dried chicken manures on the growth, yield, and N content of soybean 总被引:2,自引:0,他引:2
The present study was conducted to investigate the effects of nitrogen derived from dried or carbonized chicken manure on
growth, nodulation, yield and N content of soybean. 15N labeled chicken manure used in this study was obtained from the droppings of chicken fed on hulled rice grown under field
conditions and fertilized with 15N-labeled stable isotope ammonium sulphate and potassium nitrate fertilizers. Carbonized chicken manure was made by heat treatment
in a muffle furnace in our laboratory. This study was conducted in pots filled with clay loam soil. Results from the study
show that the application of carbonized chicken manure increased soybean seed yield by 23% and 43% for the 50 and 100 kg N
ha−1 rates respectively. Dried chicken manure application increased soybean seed yield by 7% and 30% for the 50 and 100 kg N ha−1 rates respectively. There was no difference in the N manure yield of both manures when applied at the same rate. The percentage
15N recovery was 17.6% and 8.9% for carbonized chicken manure, 19.2% and 10.5% for dried chicken manure at 50 and 100 kg N ha−1 rates respectively at peak flowering stage of soybean growth. We found high total nitrogen yields of soybean at the rate
of 100 kg N ha−1 for both manures. There was a positive relationship between number of nodules and seed yield of soybean. Total N content
also showed positive relationship with number of nodules and seed yield of soybean. We supposed that the higher P content
of carbonized chicken manure is responsible for the higher seed yield and nodule growth compared to dried chicken manure. 相似文献
1000.
选用6个大豆品种与4个不同的大豆花叶病毒株系,分别组成抗病级别不同的组合,通过对接种叶片与上位叶症状观察、苯胺蓝染色辅以荧光显微镜观察和药物学试验,探讨了不同抗病级别组合中胼胝质(即β-l,3-葡聚糖)积累的特点及其在大豆抵抗大豆花叶病毒侵染过程中的作用。试验结果表明,大豆接种病毒后,在抗病级别分别为0-3的各个组合的叶肉细胞中,在侵染早期(接种后6-72 h)不同的组合在不同时间点分别观察到了胼胝质荧光,且胼胝质荧光出现的时间与抗病级别密切相关,即品种的抗病性越强在侵染点处观察到胼胝质的时间越早;而在抗病级别为5的组合中一直未能观察到胼胝质荧光。另外,在抗病级别为0级和1级的各组合中给叶片预注射2-DDG(2-deoxy-D-glucose,一种胼胝质合成抑制剂)再接种病毒,在上位叶能观察到坏死斑的出现并且通过RT-PCR能够检测到大豆花叶病毒外壳蛋白基因。以上结果表明,大豆被大豆花叶病毒侵染后,品种的抗病性越强就会在侵染点处越早的积累胼胝质,胼胝质的沉积与大豆抗病毒侵染密切相关。 相似文献