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1.
A field experiment was carried out for two consecutive seasons 1994/95 and 1995/96 at ElRwakeeb (a sandy clay loam) to study the effect of Rhizobium sp. (Cicer) inoculation and N fertilization on six chickpea cultivars (Baladi, Gabel marra, NEC 25–27, NEC 2010, ILC 1919, and Flip 85–108). Plants were either inoculated with three Rhizobium sp. (Cicer) strains (TAL 480, TAL 620 and TAL 1148) separately, or N fertilized (50 kg N ha-1). The results of the two seasons indicated the absence of infective strains for chickpea in the soil. Rhizobium inoculation or N fertilization significantly increased the total nodule number per plant, 100 seed weight, yield and protein content of seeds. The results indicated that the three Rhizobium strains are infective and effective in nitrogen fixation. Inoculation with Rhizobium strain TAL 1148 resulted in a significant increment in most of the parameters studied, compared to other strains and untreated control. Cultivar ILC 1919 was the best yielding cultivar, whereas, cultivar NEC 2010 contained the highest protein content, however cultivar Gabel marra showed the highest amount of protein due to inoculation or N fertilization, in the two seasons. Inoculation with Rhizobium strain TAL 1148 increased yield by 72 and 70%, whereas, 50 kg N ha-1 increased it by 70 and 69% in the first and second seasons, respectively. The amounts of protein accumulated (kg ha-1) due to N or Rhizobium inoculation were determined for all cultivars. The results obtained from the inoculation were comparable to those of 50 kg N ha-1.  相似文献   

2.
包膜控释氮肥对玉米增产效应的研究   总被引:13,自引:0,他引:13  
采用包膜控释氮肥在玉米上进行肥效试验研究。结果表明,与普通氮肥(尿素)相比,控释氮肥由于其本身控制释放和缓慢释放的特点,能使耕作层土壤速效氮含量在玉米生育期内维持较高的水平,满足玉米生长对氮素的吸收需求,尤其能满足玉米中后期对养分高强度吸收的需求;显著提高玉米生长中后期植株体内氮素含量,加速氮磷钾向籽粒的转移,从而提高生物产量、经济产量和玉米品质。同等和减半施氮量条件下,玉米产量和氮素利用率都有显著提高。  相似文献   

3.
Comparative evaluation of plant growth promoting rhizobacteria viz. Azospirillum brasilense, Azotobacter vinelandii Khsr1 and chemical fertilizers was made on growth, protein, and oil yield as well as quality of canola (Brassica napus L.) cv. Rainbow. The A. brasilense and A. vinelandii were applied as seed inoculation at 106 cells/mL. The recommended doses of urea (150 kg/ha) and diamonium phosphate (180 kg/ha) were applied as sources of chemical fertilizers. First dose of chemical fertilizers was applied at the time of sowing while other three doses were applied at 45 days interval. The chemical fertilizers were highly effective in increasing leaf chlorophyll content, number of branches per plant, number of siliqua per branch, number of seeds per siliqua, and total seed yield. A. brasilense treatment increased the leaf and seed protein content (32 and 21%) as well as seed size as measured by % increase in 1000 seed weight. A. vinelandii treatment resulted in significant increase (4%) in seed oil contents but the glucosinolate and erucic acid (C22:1) contents of oil was decreased significantly. Maximum oleic acid (C18:1) content was found in seed oil of A. vinelandii treatment; whereas, significantly higher linolenic acid (C18:3) content was recorded in A. brasilense treatment. It is inferred from the present investigation that A. brasilense and A. vinelandii could be highly effective in improving yield and nutritive value of canola oil.  相似文献   

4.
Biodiesel has been recommended as an environmentally benign alternative fuel because it emits a comparatively small amount of air pollutants. Biodiesel can be processed from canola oil, which has a low liquefaction temperature owing to its high unsaturated fatty acid content, which also limits its engine-clogging effects. In this study, optimum conditions such as the amount of methanol, the alkali catalyst, and the reaction temperature were determined for production of biodiesel from canola oil. A maximum biodiesel yield was shown at an oil/methanol mole ratio of 1:6. The optimum amount of catalyst was 1 wt% of potassium hydroxide. The biodiesel yield and the methyl ester content were high when the reaction temperature was 55 °C. The consolute temperature for determining the maximum biodiesel yield was proposed in consideration of the boiling point of methanol. The energy density was analyzed for the final products of biodiesel in comparison to the raw canola oil and other plant oil based biodiesels.  相似文献   

5.
High levels of chlorophyll in harvested canola seed result in loss of revenue to producers and problems for processors. Studies on chlorophyll degradation often require plant material to be stored for some time prior to measuring the chlorophyll content. Storage of unripe canola seed in a freezer for up to one month prior to measuring the chlorophyll content did not alter the chlorophyll level in the seed. Seeds were frozen while still in the pods as well as after removal with no change in chlorophyll content over time.  相似文献   

6.
The increase in the population in Egypt makes it imperative to explore promising approaches to increase food supply, including protein and oil, to meet the needs of the Egyptian people. Cotton is the principal crop of Egyptian agriculture. It is grown mainly for its fiber, but cottonseed products are also of economic importance. Cottonseed is presently the main source of edible oil and meal for livestock in Egypt. Field experiments were conducted in two successive seasons at the Agricultural Research Center (Giza, Egypt) on cotton (Gossypium barbadense L. cv. Giza 75) to determine the effect of nitrogen (N) fertilizer rate (107 and 161 kg of N/ha applied as ammonium nitrate containing 33.5% N in two equal doses at 6 and 8 wk after sowing), together with foliar applications of plant growth retardants (mepiquat chloride “Pix”, chloromequat chloride “Cycocel”, and daminozide “Alar”, each applied once at 288 g active ingredient/ha, after 75 d from sowing) and zinc (Zn) (applied in chelated form after 80 and 95 d from sowing at 48 g of Zn/ha) on seed, protein and oil yields and oil properties of cotton. The higher N-rate, as well as the application of all growth retardants and Zn, resulted in an increase in cottonseed yield, seed protein content, oil and protein yields/ha, seed oil refractive index, unsaponifiable matter, and total unsaturated fatty acids (oleic and linoleic). These treatments tended to decrease oil acid value, saponification value, and total saturated fatty acids. The seed oil content tended to decrease as N-rate increased and increased with the application of all growth retardants and Zn. There were some differences between Pix, Cycocel, and Alar regarding their effects on the studied characters. The highest increase in seed, oil, and protein yields/ha was found with Pix, followed by Cycocel. The Cycocel treatment gave the lowest total saturated fatty acids oil content, followed by Alar.  相似文献   

7.
In northern India, the monsoon rains recede much earlier than the sowing time of post-rainy crops and the seed-zone gets dried. Excess rain water collected in near-farm or on-farm reservoirs permits small presowing and/or postsowing irrigation(s) to increase yield which is also limited by N supplies. Field experiments were conducted to match N application rates with available water supplies to optimise wheat (Triticum aestivum L.) yields. Five rates of fertilizer N (0, 25, 50, 75 and 100 kg ha–1) were combined with five irrigation treatments (no-irrigation; 5 cm and 10 cm presowing irrigation, 5 cm irrigation 30 days after sowing and; equal presowing and postsowing irrigations totalling 10 cm). The yield was regressed over crop water supply inclusive of irrigation (W) or exclusive of irrigation (W1) and applied nitrogen (N). Grain yield increased with increase in both water supply and N-rate. Within certain limits N and W1 substituted each other for yield and so did irrigation and W1. Irrespective of irrigation, the amount of N required to substitute for given W1 to maintain a given yield decreased with increasing W1. At low W1, irrigation substituted for small changes in W1 but with increased W1, irrigation substituted for larger changes in W1. Also with increase in N level given irrigation substituted for smaller amount of W1. These regressions permit recommendations of N in relation to stored water and seasonal rain with or without limited irrigation. The latter was most useful at intermediate W1.  相似文献   

8.
The effect of row space (RS) and irrigation (IR) on total protein, total oil, and fatty acid composition of Harran-grown sesame seed was studied. Total oil content of sesame varied from 46.4 to 51.5%. The oil and protein contents were significantly different among treatments (P<0.01) in 1998 and 1999. IR affected oil content significantly (P<0.01) in both years, and RS had no significant effect. The protein content was significantly influenced by RS and IR at P<0.05 and P<0.01, respectively. RS 70 cm had the highest protein content followed by RS 60, 50, and 40 cm, respectively. IR every 24th day resulted in the highest level of protein, followed by 18th-, 12th-, and 6th-day irrigation, respectively. Correlation coefficients between protein and oil content were −0.34 in 1998 and −0.59 in 1999. RS (P<0.05) and IR (P<0.01) influenced oleic and linoleic acid contents significantly. Interactions of RS and IR were also found to be significant (P<0.05) over the oleic and linoleic acid levels.  相似文献   

9.
In an effort to establish an optimum combination of water and nitrogen for winter wheat a field investigation was carried out on a coarse loamy sand soil during 1984–85 and 1985–86 to assess effects of irrigation regime (IR) and N application on yield, water use and N uptake. The treatments compromised all combinations of three irrigation regimes (IR) based on ratios of irrigation water to cumulative pan evaporation viz.1.2 (I-1), 0.9 (I-2) and 0.6 (I-3) and four rates of N, viz. 0, 60, 120 and 180 kg ha–1. Grain yield increased with increase in frequency of irrigation. In spite of wide differences in weather during the two years, scheduling of irrigation at IW/CPE = 1.2 gave the highest wheat yield on the coarse-textured soil. During 1984–85, the rainless year, grain yield under I-1 was 20 and 32 per cent higher than I-2 and I-3, respectively. With increasing N rate the yield and water use efficiency increased progressively upto 180 kg N under I-1 and upto 120 kg N ha–1 under I-2 and I-3 regimes. During 1985–86, the wet year, grain yield response to IR was relatively low. Irrespective of IR, yield increased progressively upto 180 kg N ha–1 during the wet year. Irrigation water regimes and N application also influenced leaf area index and root growth of wheat. The yield of unfertilized wheat was relatively less affected by seasonal rainfall and IR.Both N uptake and grain yield of wheat were found to increase linearly with increase in water use. Water use efficiency was highest under I-1 regime at all levels of N in the dry season of 1984–85 and under I-3 regime in the wet season of 1985–86. Increase in N uptake with increasing N rates was significantly higher under I-1 than I-2 and I-3 regimes. The N use efficiency being maximum at 60 kg N ha–1, decreased at higher N levels irrespective of IR.  相似文献   

10.
钙镁磷肥复式包膜尿素对冬小麦产量和氮肥效率的影响   总被引:3,自引:0,他引:3  
通过连续 3年 ( 1999~ 2 0 0 0年 )大田试验 ,研究了钙镁磷肥复式包膜尿素对冬小麦产量、氮效率〔包括 :氮素效率比 ( NER) ,氮吸收效率 ( NUp E) ,氮素使用效率 ( NUE)和氮肥利用效率 ( Nf UE)〕的影响。结果表明 ,钙镁磷肥复式包膜尿素与普通尿素的生物量、籽粒和秸秆量均显著大于对照处理 ;氮素使用效率 ( NUE)和氮肥利用率均显著高于对照。包膜尿素处理的产量和氮效率最高 ,其籽粒、秸秆、生物量平均值比普通尿素处理分别高 9.0 9%~15 .0 6 %、13.11%~ 14 .96 %、11.73%~ 14 .99% ,氮肥利用率高 15~ 16个百分点。在本试验条件下 ,相对于通常氮肥施用量 ( 15 0 kg N/hm2 ) ,少量增加氮肥施用量 (氮肥用量增加 8% )对产量和氮效率 ( NE)没有显著影响 ;而大量增加氮肥施用量 (增加 2 0 % ) ,能明显增加小麦产量、吸氮量和氮肥利用率  相似文献   

11.
The emphasis of this study was to investigate the effect of enzymes on aqueous extraction of canola (Brassica napus L.) seed oil and protein. Four enzymes, Protex 7L, Multifect Pectinase FE, Multifect CX 13L, and Natuzyme, were tested for their effectiveness in releasing oil and protein during aqueous extraction. The enzyme‐extracted oil content of canola seeds (22.2–26.0%) was found to be significantly (p <0.05) higher than that of the control (without enzyme) (16.48%). An appreciable amount of protein (3.5–5.9%) originally present in the seed was extracted into the aqueous and creamy phases during aqueous extraction of oil. The physicochemical properties of oils extracted from canola seed by conventional solvent extraction, and aqueous extraction, with or without enzyme addition were compared. Significant (p <0.05) differences were observed in free fatty acid content, specific extinctions at 232 and 270 nm, peroxide value, color (1‐inch cell) and concentration of tocopherols (α, γ, and δ). However, no significant variation (p <0.05) was observed in iodine value, refractive index (40 °C), density (24 °C), saponification value, unsaponifiable matter and fatty acid composition. A better oil quality was obtained with aqueous extraction (with and without enzyme) than with solvent extraction. While the enzymes enhanced the oil extraction, the oil yield was still significantly (p <0.05) lower than that obtained by solvent (hexane) extraction.  相似文献   

12.
Canola meal is highly regarded as a component of animal feed with a high protein content and a desirable amino acid profile. The presence of some components, in particular glucosinolates, sinapine and fibre, affects the value of the meal and reduces the amount that can be used in animal feed formulations. Glucosinolates in traditional cultivars (rapeseed) had very high amounts and this severely limited the usefulness of the meal. Canola breeding programs have successfully reduced glucosinolate content to trace amounts. However sinapine remains at levels sufficiently high to cause problems, particularly in poultry feed. The relatively high fibre level in canola also reduces the value of the product for animal feed. This study has determined the level of sinapine, glucosinolates and fibre in current cultivars of canola in Australia to illustrate advances made by breeding programs and limitations which still remain to raise the usefulness of a potentially valuable feedstock. Although glucosinolate levels in meal were shown to have been reduced to 11 μmol/g in some cases, sinapine remained at traditional levels of about 12–15 g/kg and neutral detergent fibre levels were about 30–40%. These issues are important priorities for canola breeders.  相似文献   

13.
Virgin olive oils were obtained in Egypt from fruits of olive trees irrigated with waters of different salinity concentration (control, 1800, 3600 and 6000 ppm) during the 1992 season. The effect of water salinity on olive oil fatty acid, fatty acid location in triacylglycerol moiety, triacylglycerol, sterol and tocopherol composition was determined. Oleic acid slightly increased and linoleic decreased in the total fatty acid composition, as well as on glycerol carbon-2 and-1(3), with increased water salinity. Trioleoyl, stearoyldioleoyl and palmitoyldioleoyl glycerols are slightly increased with increased water salinity. Total tocopherol was 87.7 mg/kg in the control and increased to 147.0 mg/kg for water with 1800 ppm salinity. At higher salinity concentration, total tocopherol decreased to 107.2 and to 89.1 mg/kg for water salinities of 3600 and 6000 ppm, respectively. The same trend was observed for α, β and γ-tocopherols. Campesterol and β-sitosterol were increased with water salinity of 1800 ppm and decreased when water salinity increased further. Stigmasterol increased at water salinity of 3600 ppm and decreased sharply when the salinity was increased to 6000 ppm. These olive oil composition studies showed that although water salinity may have some compositional effects, there was no major adverse effect on fatty acid, triacylglycerol, triacylglycerol fatty acid location, sterol and tocopherol composition for oil from olives of trees grown with water with a salt composition of up to 6000 ppm.  相似文献   

14.
Defined relationships among grain yields, water-use efficiencies (WUE) and nutrient uptake of different genotypes under varied irrigation and nitrogen (N) regimes would be invaluable for optimizing production of corn (Zea mays L.). Our objective was to evaluate these factors for six popular corn hybrids grown in Nebraska. The procedure involved measuring the effects of three supplemental irrigation rates and two N rates on yields, consumptive water use (ET), water-use efficiency, and nutrient uptake of these hybrids in one field experiment. A second field experiment evaluated effects of irrigation timing on the same characteristics of the six hybrids. Soils employed for the field experiments were Sharpsburg sicl, a typic Argiudoll, and Zook sicl, a cumulic Haplaquoll. In addition, two greenhouse experiments measured above-ground and root yields, water use, and nutrient uptake of the six hybrids under limited and high soil moisture levels.From 30–40 percent reductions in grain and stover yields occurred by limiting moisture supply in the greenhouse but with no reduction in root yields. There was only a small benefit to grain and stover yields from the higher soil moisture levels provided in the field experiments because of very favorable rainfall amount and distribution in 1979. Light, frequent irrigation was advantageous to yield and WUE over the same total amount of water applied in larger, less frequent intervals explainable in part by a N use efficiency factor. Genotype B73xMo17 produced significantly higher grain, stover, root and total yields than the other hybrids under all moisture and N regimes. Amounts of water consumed by the six hybrids in the field experiments were similar, but because of higher yields B73xMo17 had the highest WUE values. This hybrid had greater root development in the field and took up disproportionately more P, Ca, S, Fe, Cu, and Zn and less Mn and Cl than the other hybrids suggesting that its superior yielding capacity may be related to efficiency in mobilizing and utilizing certain nutrients.Contribution of the Nebraska Agric Exp Stn, Lincoln, NE as paper No. 7041 Journal Series.  相似文献   

15.
A field experiment with the winter wheat cultivar Donata was carried out on a fine-textured river clay soil in 1978. The rates of nitrogen dressing ranged from 0 to 160 kg N per ha and were split over from one up to three application times: autumn, early spring and late spring.Total above-ground dry matter and grain dry-weight yields ranged from 9.1 to 13.7 tons per ha and from 4.17 to 6.35 tons per ha, respectively. Late top-dressings increased the harvest-index, whereas an autumn dressing had the opposite effect. Number of culms per m2, grain weight (mg) and grain number per m2 increased from 350 to 430, from 35.5 to 36.8 and from 11 680 to 16 980, respectively, as the nitrogen dosage was raised from 0 to 160 kg N per ha.The linear rate of grain growth ranged from 111 to 172 kg dry matter per ha per day with nitrogen doses from 0 to 160 kg N per ha. Differences in rate of grain growth per unit area were mainly related to number of grains per m2. The association between grain number and grain yield was reflected by a correlation coefficient of 0.97 (n = 32). A higher level of nitrogen dressing enhanced the leaf area index and leaf area duration. However, we could not derive an effect of nitrogen on the duration of grain growth.Total nitrogen yield ranged from 71 to 166 kg N per ha and grain nitrogen yield from 54 to 122 kg N per ha with nitrogen dosages of 0 and 160 kg N per ha, respectively. The nitrogen concentration of the grains varied between 1.3 and 2.0 N.An autumn dressing of 40 kg N per ha generally showed only minor effects on yield and yield components. Top dressings during spring resulted in a higher recovery and efficiency of the applied nitrogen. Therefore, it may be concluded from this experiment and literature that on fertile soils an autumn dressing of nitrogen will not be economical, but split-dressings in spring are very beneficial. In particular, a late nitrogen application during the boot stage increased grain number, harvest-index and grain yield as well as protein concentration of the grain.  相似文献   

16.
Effect of nitrogen and water uptake on yield of wheat   总被引:6,自引:0,他引:6  
For 2 years, field experiments were conducted to study the direct and interactive effects of water and nitrogen uptake at different growth stages on grain yield of wheat, grown on coarse textured alluvial soil of Ludhiana. Twelve treatments comprising 3 irrigation regimes and 4 rates of N were imposed. The N and irrigation regimes showed significant interaction, especially during the drier year. Grain yield was better explained with water uptake and N uptake, when partitioned over different growth stages than with total uptake. The sensitivity factor for water uptake was higher at the reproductive stage ( = 1.60) than at the vegetative ( = 1.05) and maturation ( = 0.38) stages. Contrary, yield was more sensitive to N uptake during the vegetative stage than the reproductive and the maturation stages. Sensitivity of grain yield to water uptake was higher at higher N application rates. Yield predictability was much better (R2 = 0.98) when N and water uptake at different growth stages were combined.  相似文献   

17.
The influence of temperature during seed development on the fatty acid composition of oilseed rape (Brassica napus L.) was studied in one low-linolenic and one conventional canola cultivar. The cultivar Regent produces seed oil with ∼20% linoleic acid (C18:2) and ∼8% linolenic acid (C18:3), whereas Stellar is relatively high in C18:2 (∼25%) and low in C18:3 (∼2.5%). Both cultivars were grown in the field, and the fatty acid compositions of the seed oils were monitored throughout the period of seed development. In the field, the content of saturated (C16:0+C18:0) and monounsaturated (C18:1) fatty acids in the seed oil increased when seed developed under high temperatures. C18:3 levels were higher in seed harvested at sites with lower average daily temperatures. The low C18:3 trait of the cultivar Stellar was relatively stable over environments. Both temperature and duration of exposure to the temperature during seed development affected the fatty acid composition of the seed in a controlled environment study. Plants subjected to a high-temperature treatment (30/25°C day/night) for 40 d produced seed with the lowest C18:3 content and the highest levels of C16:0+C18:0 and C18:1. This was observed in both cultivars.  相似文献   

18.
19.
肥料组合对茎瘤芥产量和硝酸盐含量的影响   总被引:8,自引:0,他引:8  
采用田间试验研究不同肥料组合对茎瘤芥(俗名榨菜)产量和硝酸盐含量的影响。结果表明:有机无机型专用肥〔166820(有机质)〕对茎瘤芥增产和降低其硝酸盐含量的作用最佳,其次为无机型专用肥 (1979);过磷酸钙对茎瘤芥增产效果优于磷酸一铵,但降低其硝酸盐含量不及磷酸一铵;硫酸钾的增产作用优于氯化钾,但氯化钾降低硝酸盐含量的效果较好;钙镁磷肥对其增产和降低硝酸盐含量的效果均差。  相似文献   

20.
The shortening of fallow period in several areas in tropical Africa has reduced soil fertility and exposed soils to erosion and run-off. Fertilizer application and crop conservation practices are needeed to sustain high crop yield and to conserve the natural resource base for upland crop production in the continent. Field trials were carried out to evaluate the effect of fertilizer application and soil and crop residues management practices on yield of maize (Zea mays L.) planted on a Plinthudult soil at Bertoua, Eastern Cameroon. Maize yields increased significantly with nitrogen and phosphorus fertilizer application. Under the rainfall pattern prevailing in the area, the amount of nitrogen required for maximum yield was higher in the second season. On the other hand, the amount of phosphorus required for maximum yield appeared to decrease with time. The burning of crop residues and weeds prior to planting together with no-till practive gave higher yield of maize than other soil and crop residues management practices.  相似文献   

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