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1.
Thirty-three peanut cultivars were examined for their alpha-1,6 and beta-1,4 galactosidase activities and oligosaccharide contents along with proximate compositions. The average moisture, protein, fat, ash, and carbohydrate contents were: 4.9%, 26.6%, 43.1%, 2.3% and 23.1%, respectively. The corresponding coefficients of variation were: 5.2%, 10.1%, 7.2%, 7.8% and 15.7%, respectively. Raffinose and stachyose contents (%) ranged from 0.05 to 0.12 and 0.31 to 0.61, respectively. The specific activity (micromol product/min/mg protein) of crude preparation of alpha-galactosidase for the 33 cultivars ranged from 1.096 to 2.784 for the non-germinated seeds and from not being detected in some samples up to 2.432 for the germinated seeds; the mean values for non-germinated and germinated seeds were: 1.781 and 1.410, respectively. The specific activity of beta-galactosidase ranged from 0.101 to 1.727 in the non-germinated seeds and from not being detected in some samples up to 0.898 in the germinated seeds. Germination decreased the activity of both galactosidases significantly (p < or = 0.05).  相似文献   

2.
The ultrastructure of the leaves of rice(Oryza sativa)and barnyardgrass(Echinochloa crus-galli)in their milking stage were studied withelectron microscopy.The content of chloro-  相似文献   

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Prof YUAN Longping, Director of Hunan Hybrid Rice Research Center (HHRRC). won the Alan Shawn Feinstein World Hunger Awards for his research and education in Brown University of America Apr 14, 1993.  相似文献   

4.
Magnesium(Mg)affects various critical physiological and biochemical processes in higher plants,and its deficiency impedes plant growth and development.Although potassium(K)-induced Mg deficiency in agricultural production is widespread,the specific relationship of K with Mg and especially its competitive nature is poorly understood.This review summarizes current knowledge on the interactions between K and Mg with respect to their root uptake,root-to-shoot translocation and distribution in plants.Their synergistic effects on certain physiological functions are also described.The antagonistic effect of K on Mg is stronger than that of Mg on K in root absorption and transport within plants,indicating that the balanced use of K and Mg fertilizers is necessary for sustaining high plant-available Mg and alleviating K-induced Mg deficiency,especially in plant species with high K demand or in highavailable-K soil.The relationship between Mg and K in plant tissues may be antagonistic or synergistic depending on plant species,cell type,leaf age,source-and sink organs.There are synergistic effects of K and Mg on photosynthesis,carbohydrate transport and allocation,nitrogen metabolism,and turgor regulation.Definition of optimal K/Mg ratios for soils and plant tissues is desirable for maintaining proper nutritional status in plants,leading to a physiological state supporting crop production.Future research should concentrate on identifying the physiological and molecular mechanisms underlying the interactions between K and Mg in a given physiological function.  相似文献   

5.
Beta-galactosidase and peroxidase are enzymes reported to have roles in pepper maturation. Fertilizer rate may affect activity of these enzymes in fruit maturing on the plant. Nine pepper cultivars, five non-pungent and four pungent, were fertilized at two rates in field plots in 1997 and 1998 at Lane, OK, USA. Fruit were harvested at mature green, turning, and red color developmental stages, and assayed for beta-galactosidase and peroxidase activity. Overall fruit beta-galactosidase activity increased as fertilizer rate increased, and was highest in red fruit. Fertilizer rate and fruit developmental stage did not affect peroxidase activity in 1997, but peroxidase activity was highest in red fruit in 1998. Enzyme activity appeared to be cultivar dependent, and patterns differed in both years. Activities of both enzymes were higher at the red stage in many of the non-pungent peppers than in pungent peppers. These data suggest that increased fertilizer affects the activity of at least one enzyme in fruit maturing on the plant. Cultural practices affecting enzyme activity may be used to modify concentrations of components in plants that are important for human consumption.  相似文献   

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Two starch-branching enzyme (SBE) in rice, is known to be a key enzyme in amylopectin biosynthesis. The cDNA of two SBE(starch-branching enzyme) genes SheI and Shed encoding SBE Ⅰ and SBE Ⅲ (two major isoforms in rice) were cloned by an improved RT-PCR technique, from a template cDNA libray, derived from the total mRNAs extracted from the immature seeds of a japonica rice Wuyunjing 7. DNA sequence analysis showed that the size of the cloned SheI and Shed cDNAs were 2490 and 2481 bp long, respectively, including their entire coding sequences. Comparison analysis indicated that the nucleotide sequence of She3 was the same as that of shed (Genbank Accession No. D16201) as reported previously. There were only four base-pairs difference,which resulted in changes of two deduced amino acids between the cloned She1 cDNA and the reported she1 (Genbank Accession No. D11082). The cloned SheI and Shed cDNAs make it possible to improve rice starch quality through genetic engineering.  相似文献   

8.
Zeatin(Z)and zeatin riboside(ZR)are natu-rally-occurring and predominant transportablecytokinins in some higher plants.In thisstudy,the total contents of Z and ZR weremeasured in grains and roots,respectively,and their relationship with grain filling wereanalyzed.The grain filling percentage(GFP)and fertilized-grain filling percentage(FGFP)of rice cultivars IR72,IR 65600-42-5-2,IR65600-127-2-3,and IR 65598-112-2 grown infield and cultivars IR72,IR57298-174-1-1R,  相似文献   

9.
Due to the mining, smelting, sewage irrigation, agricultural runoff, and development of rural enterprises, combined pollution of Cd and Zn in soil-rice systems has frequently oceurred. This problem was studied by using the pot-culture imitative method combined with heroical analysis and mathematical models. Tested soil was brunisolic paddy soil and the tested concentrations of Cd and Zn were selected as follows: Cd (mg/kg) 0.0 0.5 1.0 1.5 2.0 3.0 Zn (mg/kg) 0.0 100 200 400 The results showed that the Cd-Zn combined pollution was more complicated than the single-factor pollution of Cd or Zn in soil-rice system: Influences of the Cd-Zn combined pollution on biological yield of rice, accumulation and distribution on Cd and Zn in tissues of rice were not only dependent on the concentration of Cd and Zn added into the tested paddy soil, but also related to their ratio. Under the condition of the Cd-Zn combined pollution, interrelationship between biological yield (Y) of rice and exponential logarithmic value  相似文献   

10.
Toprovidephysiologicalbasisforthegeneticimprovementofhybridricewithphotoinhibitionorphotooxidationtolerance,wemeasuredphysiologicalindexesrelatedtoPSⅡlightenergyconversionefficiency (Fv/Fm)andmembranelipid peroxidation.Vari etiesusedwerejaponica02428a…  相似文献   

11.
《Field Crops Research》2001,69(2):93-132
Rice (Oryza sativa L.) and wheat (Triticum aestivum L.) are now grown in sequence on the same land in the same year over 26 Mha of South and East Asia to meet the food demand of a rapidly expanding human population. This rice–wheat (R–W) system brings together conflicting and complementary practices. Much of the system operates at low yield because of inadequate nutrients and inappropriate water management. The challenge to research is to understand crop responses to the required combination of practices so that management systems can be devised for high and sustainable combined yield. The repeated transitions from anaerobic to aerobic to anaerobic growing conditions affect soil structure, nutrient relations, the growth of the component crops, and their associated pests and diseases. This review establishes realistic yield targets and discusses strategies and tactics to improve complementarity of the two crops by choice of cultivar, sowing time, mechanization, soil and water management, choice and combination of organic and inorganic fertilizers, management of weeds, pests and diseases, and the inclusion of other crops into the system, especially legumes. While research must attend to existing problems and improve resource-use efficiency of existing practices, the review suggests the need to look for new production strategies that might avoid existing constraints in some areas of the R–W region. In particular, soil, water and nutrient management strategies, such as reduced tillage and use of raised beds, that avoid the deleterious effects of puddling on soil structure and fertility, improve water- and nutrient-use efficiencies, and increase crop productivity, may be appropriate.  相似文献   

12.
The competitive adsorption of bisphenol A (BPA) and17α-ethinylestradiol (EE2) with different endocrine disrupting compounds (EDCs), such as estrone (E1), β-estradiol (E2), and estriol (E3) was investigated in the water-sediment system. The primary and interaction effects of coexisted EDCs on the adsorption of BPA and EE2 were studied in binary and multiple systems. The adsorption selectivity of sediment at different initial concentrations of EDCs was also considered, based on the distribution coefficient (β). In binary systems, coexisted EDCs exhibited a positive effect on the adsorption of BPA, while E3 showed a negative effect on the adsorption of EE2. In ternary systems, the interaction of E1*E3 and E2*BPA showed a synergistic effect on the sorption of BPA and EE2, respectively. In quaternary systems, the interaction of E1*E2*E3 showed a synergistic effect on the adsorption of both BPA and EE2. In the quinary system, coexisted EDCs all showed an antagonistic effect on the adsorption of BPA and EE2, which indicated that the coexisted EDCs competed for adsorption with BPA and EE2. EDCs in the E2-EE2-BPA system presented a superior selectivity of sediment with β values of 43.48–87.86. The order of sediment selectivity (E1 > EE2 > E2 > E3 > BPA) in binary systems was in agreement with EDCs’ adsorption capacity, which suggested that the adsorption was dominated by partition adsorption.  相似文献   

13.
正Using the trade data from the General Administration of Customs of China between January 2011 and December 2020, we estimated the index for China’s pesticide import and export, including annual import and export pesticide price index, quantity index and value index. We also calculated the terms of trade (TOT) of pesticide in total and by trade regions.  相似文献   

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A growing interest in oat (Avena ssp.) soluble fibre (β-glucan) is related to its role in the promotion of human health, and to its utilization in the production of functional foods with increased health benefits. Genetic variability and environmental conditions can exert significant effects on the grain β-glucan content. In this study 658 European oat genotypes grown in different environments in 2008 or 2009 within the European Project “Avena genetic resources for quality in human consumption” were analysed for total β-glucan content; the soluble fraction of β-glucan was also determined in a sub-set of 165 samples. Total β-glucan content ranged from 2.85 to 6.77% d.m. and the soluble fraction from 2.05 to 5.29% d.m. The estimated percentage of the soluble fraction ranged from 50.7 to 87.0%. β-glucan content and solubility were significantly influenced by both genotype and growing environment. Hierarchical cluster analysis allowed accessions with similar β-glucan compositions to be grouped. The accessions with the highest contents of both fractions included Avena sativa varieties from several countries and wild species. Finally, the data obtained were used to develop a NIRS calibration equation to predict the contents of total and soluble β-glucan in both naked and husked genotypes.  相似文献   

16.
The marine habitat has produced a significant number of very potent marine-derived agents that have the potential to inhibit the growth of human tumor cells in vitro and, in a number of cases, in both in vivo murine models and in humans. Although many agents have entered clinical trials in cancer, to date, only Cytarabine, Yondelis® (ET743), Eribulin (a synthetic derivative based on the structure of halichondrin B), and the dolastatin 10 derivative, monomethylauristatin E (MMAE or vedotin) as a warhead, have been approved for use in humans (Adcetris®). In this review, we show the compounds derived from marine sources that are currently in clinical trials against cancer. We have included brief discussions of the approved agents, where they are in trials to extend their initial approved activity (a common practice once an agent is approved), and have also included an extensive discussion of the use of auristatin derivatives as warheads, plus an area that has rarely been covered, the use of marine-derived agents to ameliorate the pain from cancers in humans, and to act as an adjuvant in immunological therapies.  相似文献   

17.
This paper presents the synthesis of metal complex acid dyes obtained from the reaction of o,o′-dihydroxyazo dyes and chromium and cobalt sulfate. The 1H-NMR, FT-IR and UV/Visible Spectrophotometer, TLC (Thin Layer Chromatography) and ICP (Ion Chromatography) of the intermediates and the metal complexes were studied and compared. Their properties such as dyeing, fastness and toxicity on nylon were also assessed according to standard methods.  相似文献   

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Plant Foods for Human Nutrition - Selenium supplementation in humans has been suggested for the prevention of chronic diseases including cardiovascular disease, cancer, and neurodegenerative...  相似文献   

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