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1.
A two-year on-farm study was carried out at Eglime in the moist savanna (MS) and Ouake in the dry savanna (DS) of Benin to evaluate the contribution of inoculation of dual-purpose soybean varieties to grain yield of upland NERICA rice fertilized with low N level. In 2005, four dual-purpose, promiscuous soybean varieties (cv. TGx1440-IE; TG×1448-2E; TG×1019-2EB; and TG×1844-18E), and a popular improved variety (cv. Jupiter) were sown in 12 farmer fields with and without Bradyrhizobium japonicum inoculation. There was also land which was left fallow that acted as the control. In 2006, upland interspecific rice (NERICA 1) was sown in all the plots and supplied with 15 kg N haL. Dry matter yield, N accumulation, and net N-balance were significantly enhanced by over 40% with inoculation of cv. TG× 1844-18E than non-inoculation in the DS in comparison to other cultivars. There were no significant effects of inoculation of previous soybean cultivars on soybean grain yield and on the succeeding NERICA rice yield. Averaged over inoculation, previous cv. TG× 1019-2EB plots supplied with only 15 kg N hal gave the highest grain yield, more than twice the yield of control plots in the DS, possibly because of significant production of higher tillers, panicles and harvest index than the other cultivars; and it could be recommended for upland rice-based system for NERICA production.  相似文献   

2.
A pot experiment was conducted to evaluate the efficiency of farm yard manure (FYM) and lime (calcium carbonate) on reducing the uptake of Cd by rice in two Cd contaminated soils of Chittagong. The effects of farm yard manure, lime and farm yard manure mixed with lime (FYM + Lime) on rice (Oryza sativa L.) growth, Cd uptake by rice and 0.1 N HC1 extractable Cd in soil were investigated. Results showed that addition of lime and farm yard manure mixed with lime significantly decreased 0.1 N HCl extractable Cd in the city sewage soil. Application of farm yard manure significantly decreased Cd concentration in rice in the city sewage soil. Lime and farm yard manure mixed with lime significantly reduced Cd concentration in rice m both the contaminated soils. Lime was more efficient than farm yard manure in reducing the uptake of Cd by rice.  相似文献   

3.
Transgenic crops having alien genes from different sources are getting popularity. A Rice (Oryza sativa L.) containing gene from Bacillus thuringiensis, a soil bacterium, was assessed to study the potential risks of transgenic plants on environment. The crop was found resistant to target insect pests. Rice variety Basmati-370 transformed with two insecticidal genes, crylAc and cry2A, was grown under field conditions for several years. Data were collected at different stages of the plant growth. Fate of Cry protein in soil, effect of Bt protein on non-target insects, risks of vertical and horizontal gene flow were evaluated. No potential hazard was found at all levels. Bt protein was unstable and degraded significantly in soil within 30 days after harvesting the crop. No harmful effects were found on non-target insects (insects other than order lepidoptera). Maximum gene flow of 0.02% was observed at close spacing and no evidence of horizontal gene transfer to Rhizobium spp. was found. In conclusion, the transgenic rice plants transformed with Bt genes have no harmful effects on the environment.  相似文献   

4.
【目的】探明非洲新稻与籼稻育性及主要农艺性状表现,为在水稻育种中利用非洲新稻资源提供理论依据和材料基础。【方法】利用非洲新稻Z3与籼稻龙特浦B杂交获得F1群体,再自交获得F2群体,在水稻成熟期调查亲本和各群体的结实率及主要农艺性状。【结果】Z3与龙特浦B杂交F1的自交结实率为70%,F2群体的自交结实率为24%~80%;F2群体中各性状都存在变异,可从中筛选到综合农艺性状优良的单株。相关分析结果表明,杂交F2群体单株产量与株实粒数、株穗数、结实率和穗长之间存在极显著正相关,与株高之间存在显著正相关。【结论】非洲新稻Z3与籼稻龙特浦B杂交后代之间不存在自交不育问题,可在水稻育种中直接利用。  相似文献   

5.
铅镉复合污染对水稻生长及产量的影响   总被引:4,自引:0,他引:4  
[目的]探讨铅镉复合污染对水稻生长、产量及品质的伤害及机理.采用盆栽试验,研究了不同程度的铅镉复合污染对水稻生长发育及产量品质的影响.[结果]铅镉低浓度胁迫能够促进水稻生长,高浓度抑制水稻的株高;铅镉胁迫显著降低了水稻的分蘖数,随着胁迫浓度增加,分蘖数下降幅度增大;铅镉胁迫显著降低了水稻每盆穗数、结实率、千粒重和产量,低浓度胁迫下每穗总粒数显著增加,高浓度胁迫下每穗总粒数显著降低;铅镉低浓度胁迫下糙米绿和精米率显著增加,高浓度胁迫下糙米率和精米率显著降低,整精米率随处理浓度的增加而显著下降;水稻籽粒中铅镉含量与土壤中铅镉浓度成显著正相关,土壤铅镉含量达到中高浓度时,水稻籽粒铅镉含量严重超标,铅镉最高超标达333%和122%.[结论]该研究为污染地区水稻栽培技术体系的建立提供依据. Abstract: [Objective] The aim was to study the damage and the mechanism of combined pollution of Pb and Cd on rice growth,yield and quality of rice.[Method]Effects of combined pollution of Pb and Cd on the growth and yield of rice were studied by pot experiment with cultivating rice. [Result] Pb and Cd could promote dce growth at low concentration while inhibit plant height at high concentration;Pb and Cd stress reduced the number of rice tillers significantly,with the increasing of stress concentration,the decrease amplitude of the number of tillers was greater;the panicle per pot,seed setting rate,1000-grain weight and yield of rice were reduced significantly by Pb and Cd stress,the grain number per panicle decreased significantly under low concentration of Pb and Cd but increased significantly under high concentration;the brown rice rate and milled rice rate increased significantly under low concentration of Pb and Cd while at high concentration of Pb and Cd,the both two reduced significantly,the head milled rice rate reduced significantly with the decreasing of concentration;The Pb and Cd content of grains were significantly positively related to the concentrations of Pb and Cd content in soil,it had excessively exceeded hygienic standard when the concentrations of Pb and Cd in soil were medium-high and the unqualified rate reached 333% and 122%.[Condusion]The study had provided basis for the establishment of rice cultivation system in pollution areas.  相似文献   

6.
Heading date of rice is a key agronomic trait determining cultivated areas and seasons and affecting yield. In the present study, ifve primary single segment substitution lines with the same genetic background were used to detect quantitative trait loci (QTLs) for heading date in rice. Two QTLs, qHD3 and qHD6 on the short arm of chromosome 3 and the short arm of chromosome 6, respectively, were identiifed under natural long-day (NLD). Nineteen secondary single segment substitution lines (SSSLs) and seven double segments pyramiding lines were designed to map the two QTLs and to evaluate their epistatic interaction between them. By overlapping mapping, qHD3 was mapped in a 791-kb interval between SSR markers RM3894 and RM569 and qHD6 in a 1 125-kb interval between RM587 and RM225. Results revealed the existence of epistatic interaction between qHD3 and qHD6 under natural long-day (NLD). It was also found that qHD3 and qHD6 had signiifcant effects on plant height and yield traits, indicating that both of the QTLs have pleiotropic effects.  相似文献   

7.
Alfalfa (Medicago sativa L.) is an important forage crop in the world and it is of great signiifcance for the improvement of its salt tolerance. To improve salt tolerance in alfalfa, a rice ascorbate peroxidase gene (OsAPX2) was introduced into alfalfa using Agrobacterium tumefaciens-mediated transformation with marker gene bar. The different T-DNA insertions in T1 transgenic alfalfa were identiifed by Southern hybridization. Three independent T2 transgenic lines were selected for stress analysis and the results showed that all of them were salt tolerant compared with wild-type plants. The transgenic plants had low levels of H2O2, malondialdehyde and relative electrical conductivity under salt and drought stresses. Moreover, the contents of chlorophyll and proline, and APX activity were high in transgenic plants under salt and drought stresses. Taken together, the overexpression of OsAPX2 enhances salt tolerance in alfalfa through scavenging reactive oxygen species.  相似文献   

8.
The aim of our study was to better understand the different responses of rice seedling to different species of inorganic arsenic As203 (As(Ill)) and Na2HAsO4 (As(V)). Our results indicate that the biomass of rice seedling decreased as arsenic concentration increased, with the decrease being more significant at higher arsenic concentrations. In addition, the analysis of superoxide dimutase (SOD), peroxidase (POD), and catalase (CAT) in rice roots and leaves showed that the activity of these three enzymes significantly decreased in rice tissues, especially in rice roots, as arsenic concentration was increased,. Further, the uptake and utilization efficiencies of N, P, and K were found to decrease as arsenic concentration was increased. However, the uptake and utilization efficiencies of P and K were mainly affected by As(IlI), whereas those of N were mainly affected by As(V). Inductively coupled plasma-mass spectrometry (ICP-MS) was used to assay arsenic accumulation in rice tissues; the results indicate that the arsenic content in rice tissues was enhanced when arsenic concentration was increased, especially in rice roots after arsenic treatment.  相似文献   

9.
The objective of this study was to evaluate the effects of elemental sulphur (S) and farmyard manure on soil pH, EC and N, S, P concentrations of tomato grown in a calcareous sandy loam soil. For this purpose, a pot experiment was conducted in greenhouse conditions. Sulphur was applied at 0, 50, 100, 150, 200, 400 mg kg~ and farmyard manure at 0, 3 ton da^-1 to the soil. Three weeks after applications, tomato seedlings were planted and 8 weeks later, the plants were harvested to determine N, S, P concentrations and dry matter yield. Soil pH and EC were determined in the soil samples taken at 3 different periods. Effects of sulphur and farmyard manure applications were not significant on N, P concentrations and dry matter yield of tomato plant. S concentration of tomato plant was increased by sulphur alone. Soil pH was decreased and soil EC was increased in both 2^nd and 3^rd soil sampling period by the sulphur applications. As a result of farmyard manure application, soil pH decreased in the 2^nd soil sampling period but increased in the 3^rd soil sampling period. Also, soil EC was significantly increased in 1^st and 3^rd soil sampling period. Farmyard manure had no significant effect on S supply to tomato plant. The N:S ratio of tomato plant was decreased by sulphur alone. However, the sulphur with farmyard manure applications decreased N:S ratio in lesser extend compared to the S applications.  相似文献   

10.
To further utilize bioactive substance such as bovine colostrum sIgA and IgG, sIgA and IgG were isolated and purified simultaneously by salting out, ultrafiltration and gel chromatography, etc. The analysis of results were showed quantitatively by nonhydrogenized SDS-PAGE, and quanlities of sIgA and IgG were respectively detected by Western Blot. The results showed that the purity and yield of bovine colostrum sIgA were 85.3% and 42.8%, respectively, while the purity and yield of bovine colostrum IgG were respectively 97.2% and 64.4%. This preparative method provides theoretical and experimental foundation for sIgA industrial production.  相似文献   

11.
The effect of N levels and sources on the antioxidant components in vegetable is not completely understood. Therefore, greenhouse experiments were conducted to determine the changes in antioxidant capacity diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP), total phenolics, ascorbic acid, total carotene and lycopene contents in edible portions of lettuce, onion and tomato due to different nitrogen levels and sources. The experiment included three N levels (20, 40 and 60 kg/ha for lettuce trial and 60, 120 and 180 kg/ha for either onion or tomato) and four nitrogen sources (calcium nitrate, ammonium sulphate, ammonium nitrate and urea). The antioxidant capacity and phenolic contents in lettuce was enhanced under low nitrogen level, while the antioxidant capacities, phenolics, carotenoids and lycopene in tomato fruits were not significantly affected by the nitrogen dose applied. Application of calcium nitrate caused 50% increase in DPPH and 20% in FRAP of lettuce compared to other nitrogen forms. Tomato treated with calcium nitrate or ammonium sulphate had higher phenolic and ascorbic acid contents than treated plants with ammonium nitrate or urea. Antioxidant tested parameters of onion were not significantly affected by the nitrogen treatments. Nitrogen concentration in tomato fruits significantly correlated with FRAP antioxidant capacity, phenolics, ascorbic acid, carotene and lycopene contents.  相似文献   

12.
Cowpea (Vigna unguiculata L. Walp.) and tomato (Lycopersicum esculentum L. Karst) are attacked by a wide range of insect pests worldwide. In many cases, pesticides are used to control the pests. In 2010 and 2011, we conducted field experiments to evaluate and compare the effectiveness of a biorational (Agroneem~) and conventional pesticide (imidacloprid or thiamethoxam) on insect pests of these crops. In the first year, two varieties of cowpea (Mississippi Silver and Pinkeye Purple Hull) and two of tomato (Mariana and German Johnson) were used; in the second year, the better performing of each group (Mississippi Silver and Mariana) were used for the study. A split-plot design with four replications in Year 1, and a randomized complete block design with six treatment combinations in Year 2. In the first year, both pesticide groups were applied following manufacturer's recommendation (10-14 d cycles); and in the second year, the application of the pesticides was driven by economic thresholds level (ETL) of insect pests. The most prevalent species of insects recorded in both crops were in the families: Chrysomelidae, Pentatomidae, Cicadellidae, Vespidae, Sarcophagidae, Thripidae and Sphingidae. In both years, the diversity of insects on cowpea was greater than on tomato and more insects were observed in the second year compared to the first, despite the absence of significant difference (P 〉 0.05) between varieties in the treated plots. The yield of cowpea and tomato was comparable in all sprayed plots.  相似文献   

13.
The combined effects of salinity with low root zone temperature (RZT) on plant growth and photosynthesis were studied in tomato (Solanum lycopersicum) plants. The plants were exposed to two different root zone temperatures (28/20℃, 12/8℃, day/night temperature) in combination with two NaC1 levels (0 and 100 mmol L-l). After 2 wk of treatment, K+ and Na~ concentration, leaf photosynthetic gas exchange, chlorophyll fluorescence and leaf antioxidant enzyme activities were measured. Salinity significantly decreased plant biomass, net photosynthesis rate, actual quantum yield of photosynthesis and concentration of K+, but remarkably increased the concentration of Na+. These effects were more pronounced when the salinity treatments were combined with the treatment of low RZT conditions. Either salinity or low RZT individually did not affect maximal efficiency of PSII photochemistry (Fv/Fm), while a combination of these two stresses decreased Fv/Fm considerably, indicating that the photo-damage occurred under such conditions. Non-photochemical quenching was increased by salt stress in accompany with the enhancement of the de-epoxidation state of the xanthophyll cycle, in contrast, this was not the case with low RZT applied individually. Salinity stress individually increased the activities of SOD, APX, GPOD and GR, and decreased the activities of DHAR. Due to the interactive effects of salinity with low RZT, these five enzyme activities increased sharply in the combined stressed plants. These results indicate that low RZT exacerbates the ion imbalance, PSII damage and photosynthesis inhibition in tomato plants under salinity. In response to the oxidative stress under salinity in combination with low RZT, the activities of antioxidant enzymes SOD, APX, GPOD, DHAR and GR were clearly enhanced in tomato plants.  相似文献   

14.
The study was conducted in four states of the Southwest geo-political zone in Nigeria and four regions in Ghana.. The results showed that the existing forest, agricultural and land use decree/policies in Nigeria and Ghana indicated lack of integration between Forestry and Agricultural land uses. The main conflicting areas were obsolete land use decree in Nigeria and lack of national land use policy in Ghana. The causes and effects of the conflicts had policy enunciation, stakeholders, and institutional and managerial dimensions. Some of the causes of the conflicts were lack of national land use policies for coherent and integrated forest and agricultural sectors; high population growth, de-reservation of forest reserves, unsustainable agricultural practices and technologies, land hunger, encroachment of forest reserves with cash crops and stakeholders' litany of demands and other diverse interests. Consequences of conflicts in the study locations included disharmony between forestry officials and farmers, antagonism between timber concenssionnaires and communities, wanton destruction of economic trees and seedlings, extinction of tree species, expansion of illegal farm lands and an attendant poverty. The logistic regression model for conflicts between forestry and agricultural land uses in Nigeria and Ghana indicated significant fit to the data judging from chi square value (df, 9) = 3174.1 that is significant at P 〈 0.05. The final loss of the model indicated a value of 92.47.  相似文献   

15.
The effects of different tillage systems and poultry manure on soil physical properties, performance and nutrients in sorghum were studied for three years at Owo, southwest Nigeria. There was factorial combinations of herbicide-based zero tillage (ZT), manual clearing (MC), disc ploughing (P), ploughing plus harrowing (P+H) and ploughing plus double harrowing (P+2H), and two rates of poultry manure at 0 and 7.5 Mg ha^-1. Herbicide-based zero tillage and manual clearing reduced soil temperature and conserved more water than mechanized tillage techniques. Poultry manure reduced soil bulk density and temperature and increased soil water and porosity. There was a percentage decrease of leaf N, P, K, Ca and Mg concentrations, plant height, leaf area, stem girth, root dry weight, dry matter and grain yield in ascending order for herbicide-based zero tillage, manual clearing, ploughing, ploughing plus harrowing and ploughing plus double harrowing while percentage increases were recorded in a descending order for all the various combinations of tillage with poultry manure in that order. Poultry manure in combination with tillage increased dry matter and grain yield by 33.1 and 39.5%, respectively in comparison with tillage only. The manure-zero tillage methods increased dry matter and grain yield by 8% and 15%, respectively when compared with manure-mechanized tillage methods. Zero tillage or manual clearing in combination with 7.5 Mg ha^-1 poultry manure was most suitable for sorghum cultivation.  相似文献   

16.
English grain aphid (EGA) is a destructive insect pest of wheat. To identify the loci associated with EGA resistance and tolerance, 70 bread wheat accessions mainly from central Asia were evaluated for EGA resistance and tolerance traits at two locations, and genotyped with 51 SSR markers. Totally, three accessions showed high or moderate levels resistance and 17 genotypes displayed highly or moderately tolerate to EGA. Genetic diversity of these lines was investigated also. After 97 SSR loci which evenly covered all wheat chromosomes were scanned for association, four SSR loci were significantly associated with EGA resistance and four with EGA tolerance. After association analysis was conducted with dynamic aphid densities, we found four loci Xgwm192b, Xgwm391, Xbarc98, and Xgwm613b were detected continuously at different growing stages of wheat. In addition, the loci of EGA resistance/tolerance and Russian wheat aphid resistance were compared. The results generated in this study would be helpful for utilization of the EGA resistance/tolerance germplasm, and for development of mapping populations in EGA resistance breeding programs.  相似文献   

17.
The study aimed at evaluating the nutrient and nutraceutical potentials of the selected seaweed biomass namely Ulva lactuca and Kappaphycus alvarezii. The selected seaweeds were found to be rich in macro and micronutrients. Kappaphycus contained high amount of ash when compared to U. lactuca. It is revealed that the mercury level in U. lactuca was 0.017 ppm and it was not detected in K. alvarezii. The heavy metal concentration in the selected seaweeds was within the tolerable value reported as quality criteria for edible seaweeds. These seaweeds were also found to be rich sources of vitamin antioxidants namely Vitamin C, total carotenoid, beta carotene, total chlorophyll and polyphenol. The phytochemical screening of the selected seaweeds showed that both seaweeds contained carbohydrates, protein, gums and mulicage, phenols, starch and quinones. Alkaloids was absent in Kappaphycus, saponins was moderate in U. actuca when compared to Kappaphycus. Glycosides, flavonoids, tannins and terpenoids were absent in both the species. The selected seaweeds also possess antibacterial activity. The selected biomass could be recommended for use in dietaries to combat protein energy malnutrition and in particular micronutrient deficiencies.  相似文献   

18.
Some engineering properties of sunflower seed and its kernel, Shahroodi variety as a case study, were investigated at various moisture content levels (3-14% d.b.) for three size categories (large, medium and small). With increase of moisture content from 3 to 14% d.b., all the main dimensions (length, width and thickness), geometric mean diameter, porosity, true density, terminal velocity and static coefficient of friction increased while bulk density and rupture force for both sunflower seed and its kernel decreased for all size categories. The results showed that the highest value of static coefficient of friction for both seed and kernel was on the rubber surface, followed by plywood, polyethylene, galvanized iron, and finally aluminium surfaces. The seeds required less compressive force to dehull when loaded under the horizontal as compared to the vertical orientation. But for kernels, the trend was the opposite. Also, the compressive forces needed to initiate rupture of sunflower seed hulls were higher (47.1-94.72 N) than those required to rupture the kernel (8.5-13.4 N) in both orientations.  相似文献   

19.
Carbon and nitrogen are the most important elements in the terrestrial ecosystem. Studying carbon and nitrogen distributions in plant and soil is important for our understanding of the ecosystem dynamics and carbon cycle on arid lands. A study was conducted in a typical arid area, the Yanqi Basin, Northwest China. Carbon and nitrogen distributions in plant tissues and soil profiles were determined at 21 sites with typical native plants and crops. Our results indicated that carbon content was similar between crops and native plants, and the average carbon contents in aboveground (42.4%) and belowground (42.8%) tissues were almost the same. Average nitrogen contents in crops were nearly the same (~0.7%) in aboveground and belowground tissues whereas mean nitrogen content was approximately 100% higher in aboveground (2.2%) than in belowground (1.2%) tissues for native species. Soil organic carbon (SOC) and total nitrogen (TN) in cropland (9.4 and 0.9 g kg^-1) were significantly higher than those in native land (6.2 and 0.7 g kg^-1). Multiple regression analyses indicated that carbon content in belowground tissue and nitrogen content in aboveground tissue were key factors connecting plant and soil in native land. However, there was no significant relationship for carbon or nitrogen between soil and crop, which might reflect human disturbance, such as plowing and applications of various organic materials.  相似文献   

20.
This study was carried out at the Genetic Engineering Lab, College of Agriculture, University of Basrah. DNA was extracted from samples containing meat of commercial products in the Basrah markets. The products subjected to analysis using polymerase chain reaction (PCR) with species specific repeat (SSR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques based on the sequence of the mitochondrial DNA cytochrome b gene (mtDNA cyt b gene). Then digestion with the Alu l restriction enzyme to establish a differential diagnosis detects and discriminates between meat species and adulteration in the products. SSR primers were applied, has been detected amplification of the encoded gene product, generated 221 bp in some imported minced and canned meat samples. The results show that SSR analysis produced a pattern that allowed a direct identification of horse and donkey meats in some imported minced and canned meat samples (Hana, Monde and Bavaria). The amplified 359 bp gene of mtDNA cyt b gene from samples in different product was cut using Alu 1 restriction enzyme resulting in restriction fragment length polymorphism (RFLP). Alu 1 was used to distinguish between the animals meat that belong to the family or one species. The digestion of the PCR product showed differences between products. Where the fragment length generated were 74, 76 and 189 bp. It belonged to horse meat. The fraud was detected in Hana, Monde and Bavaria products available in Basrah markets showing the presence of horse meat in these products that labeled as beef meats 100%. This revealed mtDNA cyt b gene as highly conserved and consequently a good molecular marker for diagnostic studies. Thus, this technique can be applied to food authentication for the identification of different species of animals in food products.  相似文献   

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