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1.
Measurement of root reductant levels developed during plant Fe stress was tested as a possible assay for sorghum cultivar Fe‐efficiency screening. Iron‐stressed sorghum was shown to release reductants into CaCO3 buffered nutrient solution; however, considerably more plants could be tested by extracting reductants from excised roots of Fe‐stressed sorghum in 35 ml of pH 3 nutrient solution and 1 mM glucose. An Fe‐efficient cultivar, RT×2536, and an Fe‐inefficient cultivar, BT×378, could be separated by measurement of reductants released into CaCO3 buffered nutrient solution and by an excised root extraction method; however, neither method was as effective as visual rating methods.  相似文献   

2.
Sorghum [Sorghum bicolor (L.) Moench] cultivars were planted in 8 cm × 8 cm × 8 cm pots filled with ‘white quartz flintshot’ sand containing 0, 0.25, 0.50, 1.0, or 2.0 mg/kg metolachlor [2‐chloro‐N‐(2‐ethyl‐6‐methylphenyl)‐N‐(2 methoxy‐1‐methylethyl)acetamide] and the pots were watered on alternate days with 100 mL 0.1 M sodium acetate at pH 6.0, 5.5, 5.0, 4.5, or 4.0 to determine the influence of excess H+ and metolachlor concentrations on sorghum root growth. Cultivars utilized were Funk G522DR, SC574, SC283, GP‐10, 58M, and 38M. At pH 4.5 and 4.0 (0 metolachlor), root lengths of Funk G522DR and SC574 were significantly decreased compared to roots from plants grown at pH 6.0. The other four cultivars had decreased root growth at pH 4.0 (0 metolachlor). Metolachlor influence on sorghum cultivar root growth was dependent on pH, cultivar, and metolachlor concentration. None of the cultivars showed increased metolachlor activity which was influenced by pH. Metolachlor (0.25 mg/kg) reversed the influence of excess H+ concentration (pH 4.0) in SC574. Metolachlor (0.5, 1.0, and 2.0 ppmw) reversed the excess H+ concentration inhibition of root growth at pH 4.0 in Funk G522DR.  相似文献   

3.
The relationship between the slow digestion property of cooked maize starch and its molecular fine structure was investigated. Results of the in vitro Englyst assay showed a range of rapidly digestible starch (RDS) (70.1-98.9%), slowly digestible starch (SDS) (0.2-20.3%), and resistant starch (RS) (0.0-13.7%) among the tested maize mutant flour samples. Further analysis showed that amylose content was significantly correlated ( R = 0.763, P < 0.001) with RS amount but not with that of SDS, indicating that amylopectin is the starch molecule associated with SDS. Total starch debranching analysis revealed a parabolic relationship between SDS content and the weight ratio of amylopectin short chains (DP < 13, named SF) to long chains (DP >/= 13, named LF), which means amylopectin with a higher amount of either short chains or long chains can produce relatively high amounts of SDS. Furthermore, debranching analysis of the SDS materials from samples with the highest and lowest weight ratios of SF/LF (both had a high amount SDS) showed significantly different profiles, indicating there is not a uniform molecular structure for SDS. Thus, genetic mutants of maize samples have a good potential to provide raw starch materials of high nutritional quality. An additional finding showed that a simple and comparably high-throughput technique of Rapid Visco-Analyzer (RVA) can be used to screen genetic mutants on the basis of their RVA profiles.  相似文献   

4.
5.
Moisture deficit, poor soil fertility and lack of improved varieties constrained sorghum production in north-eastern Ethiopia. An experiment was conducted in 2002 at Kobo and Sirinka in north-eastern Ethiopia to study the possible effects of seedbed, nitrogen fertilizer and cultivar on the yield and N use efficiency (NUE) of sorghum. The experiment was carried out in a split–split plot design with seedbed (tied-ridge vs. flatbed planting) as main plots, N fertilizer (0, 40 and 80 kg N ha?1) as subplots and sorghum cultivars (Jigurti, ICSV111 and 76T1#23) as sub-sub plots, with three replications. At Kobo, the seedbed by cultivar interaction affected all parameters. Nitrogen fertilization increased biomass yield and NUE at both locations and grain yield at Sirinka. Cultivars showed different performance where ICSV111 and 76T1#23 were superior in grain yield, N uptake and concentration, N harvest index and NUE of grain (NUEg) compared with Jigurti. Thus, planting ICSV111 and 76T1#23 in tied-ridging and with N fertilization at Kobo and in flatbed and with N fertilization at Sirinka is recommended. This study revealed that tied-ridging is not a solution in all areas where moisture deficiency is a problem. Its effectiveness is affected by rainfall amount and soil type.  相似文献   

6.
7.
Abstract

Fertilizer phosphorus (P) use on Vertisols of the semi‐arid zone in India is becoming more common, so it is important that for developing P management strategies the residual value of P is allowed. Little information is available on this aspect for crops such as sorghum under rainfed cropping. A field experiment was conducted for three years to study the response of sorghum to fertilizer P (0, 10, 20, and 40 kg P ha‐1) in the absence and presence of P residues from the preceding year on a Vertisol (Typic Pellustert), low in extractable P (0.4 mg kg‐1 soil Olsen‐P). Despite the variable rainfall received during the cropping season (June‐September), P applied in the previous season had strong residual effects. Sorghum yield and P uptake in treatments in which P was applied at 20 or 40 kg P ha‐1 once in two years was at par with or higher than in treatments in which 10 kg or 20 kg P ha‐1 was added every year. Ninety percent relative grain yield was achieved at about 20 kg ha‐1 of fresh P and the results presented show that application of 40 kg P ha‐1 once in two years can satisfactorily meet the P requirement of sorghum on the Vertisol.  相似文献   

8.
驻芝15号是河南省驻马店市农业科学研究所以驻81043为母本、驻92701优系为父本,经有性杂交,后代在多元病圃连续鉴定选育而成的高产、优质、早熟、多抗的芝麻新品种,2005-2006年参加了全国(江淮片)芝麻品种区域试验和生产试验,2007年4月通过全国芝麻品种鉴定委员会鉴定.  相似文献   

9.
A bioassay-guided fractionation of water extracts from Helianthus annuus cv. SH-222 was carried out. Ten lignans and a phenylpropanoid were isolated from the polar bioactive fractions of H. annuus. This study is the first to report lignans as constituents of sunflower and is the first time that tanegool has been isolated as a natural aglycone. Additionally, we report biological activities of the isolated compounds. The general bioactivity has been evaluated using the wheat coleoptiles bioassay. The phytotoxic activities of compounds pinoresinol, lariciresinol, dihydro-dehydrodiconiferilic alcohol, and l-(4'-hydroxy-3'-methoxyphenyl)-2-[4' '-(3hydroxypropyl)-2' '-methoxyphenoxy]propane-l,3-diol were also evaluated in a bioassay on the standard target species. The structure-activity relationships are discussed.  相似文献   

10.
酶法制备玉米缓慢消化淀粉的工艺条件优化   总被引:2,自引:1,他引:1  
缓慢消化淀粉是一种新型功能性淀粉,具有多种生理功能。该文以蜡质玉米淀粉为原料,采用酶控制降解技术及湿热-冷却技术制备缓慢消化淀粉,确定其优化工艺条件。研究结果表明:普鲁兰酶用量9 U/g,酶作用时间7 h,淀粉乳浓度12.5%,热处理时间50 min,热处理温度110℃,储藏温度1℃,储藏时间2 d,烘干温度60℃,并在此条件下进行3次重复试验,缓慢消化淀粉得率为27.33%。  相似文献   

11.
A survey of compositional characteristics of the aerial part of sheep's burnet (Sanguisorba minor ssp. muricata) growing in Mediterranean French pastures has been undertaken. Investigations with scanning electron microscopy gave the morphological structure of this plant, in particular for akene ornamentation. Taxonomic characters confirmed the identification of the muricata subspecies. Moisture, ash, free sugars, cellulose, amino acids, and fatty acids of the whole aerial part were determined. Besides the major component, cellulose (20.4%), amino acid analysis showed that proteins contained mainly glutamic acid plus glutamine (0.67%) and aspartic acid plus asparagine (0.56%). The main fatty acids were palmitic (29.1%), linoleic (22.6%), and linolenic (21.4%).  相似文献   

12.
Aluminum toxicity is an important limitation to crop yields in the acid soils of southeastern U. S. and other parts of the world due to its detrimental effects on roots. Soluble organics in soil solution ameliorate Al toxicity, a phenomenon which can be studied employing synthetic chelates. Theoretical models predict that Al will be complexed on nearly a one to one molar basis by nitrilotriacetic acid (NTA) at toxic pH levels found in acid soils (4.0 to 4.5). A series of growth chamber experiments were conducted with NTA at various Al and pH levels to test equilibrium models using sorghum [Sorghum bicolor (L.) Moench] as a bioassay for the uncomplexed Al. At pH 3.5 neither Al nor NTA affected root growth which was very poor, probably because of H+ toxicity. At pH 4.0 and 4.5 root growth was reduced by Al levels, and NTA ameliorated toxicity as predicted by the theoretical model. Root length was reduced at pH 4.0 relative to pH 4.5 indicating that H+ ion was toxic at pH 4.0. The bioassay method was successful in confirming the model for Al-chelate equilibria for NTA. Differential pulse polarography was found to be sensitive to the uncomplexed Al and may have potential in determining toxic Al in soil solution.  相似文献   

13.
In an effort to characterise and select promising sweet stem sorghum genotypes with enhanced biofuel productivity, the present study investigated phenotypic variability present among diverse sweet stem sorghum genotypes based on ethanol production and related agronomic traits. One hundred and ninety genotypes were evaluated. Data were subjected to variance, cluster, correlation, path coefficient and principal component analyses. Significant differences (P?<?0.01) were detected among tested genotypes for all measured traits. Days to flowering varied from 62 to 152 with a mean of 93. Plant height varied from 90 to 420?cm with a mean of 236?cm. Stem diameter ranged from 7 to 31?mm with a mean of 16?mm. Biomass yield varied from 6.668 to 111.2?t?ha?1 with a mean of 30?t?ha?1. Stalk dry matter content ranged from 17.2% to 44.2% with a mean of 29.8%, while fibre content varied from 8.92% to 34.8% with a mean of 17.2%. The stalk brix yield varied from 3.3% to 18.9% with a mean of 12.1%. Ethanol productivity ranged from 240.9 to 5500?l?ha?1 with a mean of 1886?l?ha?1. The best ethanol producing genotypes were AS203, AS391, AS205, AS251 and AS448. Days to flowering, plant height, stalk brix and stem diameter exerted the greatest indirect effects on ethanol production through higher biomass production. Biomass yield had the greatest direct effect on ethanol production. Therefore, the above traits should be considered during breeding sorghum for bio-ethanol production. Also, the traits had high heritability values, hence selection should provide for good genetic gains. Overall, the above sweet stem sorghum genotypes are useful genetic resources for breeding of sorghum with enhanced bio-ethanol production.  相似文献   

14.
本试验研究不同的日粮电解质平衡值(dEB值)对银香麻鸡生产性能和血液理化指标的影响。结果表明:(1)第一个阶段(小鸡阶段),对于日增重而言,日粮中适宜的dEB值范围为50~300 mmol/kg,其中以200 mmol/kg为最佳;第二个阶段(大鸡阶段),日增重较好的dEB值范围为150~300 mmol/kg,其中以250 mmol/kg为最佳。(2)在日粮中添加NaHCO3和CaCl2来调节dEB值时,对于血清中的各种无机成分(钠、钾、氯、钙、磷、HCO3^-)的浓度都有不同程度的改变,但并未引起血清中相应的Na^+、HCO3^-、Ca^2+和Cl^-的含量发生正相关的变化。不同的dEB值对血清pH值也无显著影响(P〉0.05)。  相似文献   

15.
Four-day-old seedlings of spring wheat (Triticum aestivum L. cv. Marvdasht) can tolerate severe dehydration and recover after re-watering. In order to clarify tolerance mechanism, in a completely randomized design, the seedlings were exposed to drought by complete water cessation for 10 and 20 days, followed by re-watering for 3 and 7 days. Upon dehydration, the activity of α-amylase increased whereas growth parameters; photosynthetic pigments; and the activities of lipoxygenase, indole acetic acid (IAA) oxidase, and ascorbate peroxidase (APX) decreased. The activity of APX and the expression of its gene, however, increased after re-watering. Prolonged dehydration was also accompanied by increase in sucrose, soluble proteins, fructans, and certain amino acids, e.g. proline, glutamine, and valine. The results indicated that during dehydration, 4-day-old wheat seedlings shifted their energy expenditure from basal metabolism to withstand water deficiency via lowering the activity of membrane-damaging enzymes and enhancing the production of osmoprotectants.  相似文献   

16.
Butterfly assemblages were used to characterize and evaluate the conservation value of the main habitat types in the Aiguamolls de l’Empordà Natural Park (north-eastern Spain), an important protected wetland area on the Mediterranean coast. Butterfly data were obtained from a number of transects walked as part of the Catalan Butterfly Monitoring Scheme, which uses a standardized methodology for monitoring butterflies. A Mantel test indicated a strong association between habitat types and the composition of butterfly assemblages and a principal component analysis ordinated individual butterfly species along a gradient from woodland to open areas, thereby indicating various degrees of shade tolerance. In addition, cluster analysis distinguished two main groups of habitats based on the similarities of their butterfly fauna: woodland and bramble clumps and a group of three different kinds of grasslands (traditionally hay meadows, pastures, and alfalfa fields). Hay meadows flooded in winter (the so-called closes) appeared always as the highest ranked habitat in terms of conservation evaluation: they have more butterflies and a slight tendency to harbor more and generally rarer species. This conclusion coincides with that of previous investigations that have indicated that the most diverse and rare plant communities in the whole Natural Park are present in the closes, and highlights the importance of traditionally managed hay meadows for wildlife. However, these hay meadows - one of the rarest habitats in the Mediterranean region - are in alarming decline and have become the most threatened habitat in this protected area: no longer profitable, we believe that the future of the closes will depend ultimately on the existence of agri-environmental schemes.  相似文献   

17.
The phenolic composition of wine depends on, among other factors, the grapes used to make it. In this sense, knowledge of the chemical composition of grapes and its association with the resulting wines is an important tool to determine if there is a relationship between the phenolic composition of grapes and the price that these wines obtain in the market. For this purpose, grape skins and seeds from the cultivar Cabernet Sauvignon from the central region of Chile, in 2009 and 2010 vintages from two ripening points, were subjected to chemical and phenolic analyses, as were the wines made from these grapes. Grapes and the corresponding wines from three retail price wine categories, U.S. $6-8, U.S. $28-30, and U.S. $150-160, were evaluated. No differences were found across the price categories in the chemical analysis of grapes. Berry skins and wines from the higher price categories presented a higher concentration only of total tannins, and the differences in their concentrations were only among the different fractions of proanthocyanidins in the skins, seeds, and wines; there were no differences in their proportions. A seasonal effect influenced the concentrations of certain compounds in grapes and led to a decrease in the concentration of total phenols, total tannins, and total anthocyanins between sampling dates as harvesting moved toward the common commercial grape harvest in Chilean viticulture.  相似文献   

18.
A sorghum core collection representing a wide range of genetic diversity and used in the framework of a sorghum breeding and genetics program was evaluated by near-infrared reflectance spectroscopy (NIRS) to predict food grain quality traits: amylose content (AM), protein content (PR), lipid content (LI), endosperm texture (ET), and hardness (HD). A total of 278 sorghum samples were scanned as whole and ground grain to develop calibration equations. Laboratory analyses were performed on NIRS sample subsets that preserved the core collection racial distribution. Principal component analysis performed on NIRS spectra evidenced a level of structure following known sorghum races, which underlined the importance of using a wide range of genetic diversity. Performances of calibration equations were evaluated by the coefficient of determination, bias, standard error of laboratory (SEL), and ratio of performance deviation (RPD). Ground grain spectra gave better calibration equations than whole grain. PR equation (RPD of 5.7) can be used for quality control. ET, LI, and HD equations (RPD of 2.9, 2.6, and 2.6, respectively) can be used for screening steps. Even with a small SEL in whole sample analysis, a RPD of 1.8 for AM confirmed that this variable is not easy to predict with NIRS.  相似文献   

19.
Sorghum is one of the water- and nutrient-use efficient crops raised in dry regions worldwide. A 3 × 3 split-plot experiment in randomized complete block design was conducted to study the effects of petroleum refinery waste aqueous ammonia (NH3) on irrigated fodder sorghum for two consecutive growing seasons. The main plots consisted of 0 (control), 40, and 80 kg N ha?1, respectively, and the injection depths (surface 15 cm, and 20 cm depth) were assigned to sub-plots. A significant effect of NH3 on both fresh and dry biomass production was observed where the highest yield was recorded from the 80 kg N ha?1 than the control and 40 kg N ha?1, respectively. Sorghum biomass yield increased most when NH3 was injected at 20 cm depth as compared to other depths. Biomass nutrient content and nitrogen-use efficiency were increased when 80 kg N ha?1 was applied as compared to the control. The critical limit of K:(Ca+Mg), above which the tetany risk increases, did not exceed in sorghum biomass by NH3 fertilization. Results suggested that industrial waste NH3 equivalent to 80 kg N ha?1 injected at 20 cm depth can be a sustainable approach to fertilize irrigated sorghum growing as a forage crop.  相似文献   

20.
采用体外透析法测定了19种植物性饲料和2种混合饲粮磷的透析率,考察了饲料总磷、植酸磷和植酸酶与透析率之间的关系,建立了体外法预测饲料可消化磷的数学模型。结果表明:外源植酸酶的添加可以显著提高磷的透析率,且这种作用对内源植酸酶含量低的饲料效果更加明显;从绝对值看,体外法测得的透析率比真消化率低,但体外法可以较准确地比较不同饲料有效磷的高低;用于预测饲料可透析磷的方程为:Y=-0.725+0.566×总磷(g/kg)-0.35×植酸磷(g/kg)+0.0044×植酸酶(g/kg)(R2=0.918,RSD=0.207,P<0.001);可以通过体外法与体内法建立的回归模型来预测饲料真可消化磷的含量,预测方程为:真可消化磷(g/kg)=0.542+1.017×可透析磷(g/kg)(R2=0.899,RSD=0.261,P<0.0001)。  相似文献   

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