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1.
The nutritional value of wild underexploited vegetable samples collected in the Argentine Chaco was investigated. Leaves from Hipochaeris sp.-, Coronopus didimus and Portulaca olearacea; fruits from Zyziphus sativa, Brumelia obtusifolia and Eugenia uniflora; and roots of Canna coccinea were included in this work; several separate samples being taken at least during two consecutive harvesting seasons. Values for moisture, protein, total lipids, crude fiber, ash, reducing and total sugars, starch, total pectins and energy are given. Mineral micronutrient contents are reported for calcium, potassium, magnesium, iron and phosphorus, as well as vitamin values (ascorbic acid and beta-carotene). Higher concentrations of macronutrients were found in the leafy vegetables (32-50 Kcal/100 g) than in commercially exploited cultivars (14-30 Kcal/100 g), as shown by an increased energy value, the protein content of Portulaca olearacea (3.74 g/100 g) being highly remarkable. Unusually high micronutrient figures were also determined in Coronopus didimus, with 172.3; 3.98, and 46.7 mg/100 g, for calcium, iron and magnesium, respectively. In general, fruits also showed higher macronutrient contents, with the exception of proteins, with less but constant values (1.58 to 1.74 g/100 g), although contributing more energy than commercial cultivars (70 to 147 Kcal/100 g). Equally important proved to be the provitamin A content in Eugenia uniflora (11.98 mg/100 g). Roots of Canna coccinea revealed the lowest energy value (34 Kcal/100 g) but surprisingly, the highest content of phosphorus of all the species under study.  相似文献   

2.
The investigation studied the optimal fertilizer rates and mixtures for maximum production of smooth cayenne pineapples in the tropical ferrallitic soil.Fertilized pineapples were significantly (P = 0.05) superior in growth and fruit yield to the unfertilized control. Nitrogen and potassium were the most critical nutrients. Nitrogen deficiency manifested within 6 months of planting as reduced, thorny and pink coloured leaves resulting in over 10 months delayed plant crop harvest and over 38% reduction in fruit yield. Less than 20% of pineapples which lacked nitrogen remained productive during the first ratoon crop. However, when nitrogen was increased twofold (100 to 200 kg/ha/year), the fruit of the plant crop doubled with 15-10% increased fruit lodging. Potassium significantly (P = 0.05) reduced fruit lodging and improved fruit yield and flavour.Nitrogen further enhanced the effective utilization of P and K for significant yield increases. Thus, the interaction between high nitrogen (200 kg/ha/year) and low phosphorus (50 kg/ha) or high potassium (200 kg/ha) respectively, significantly (P = 0.05) increased the yield of pineapples, while P and K interaction retarded growth, delayed crop maturity and reduced the fruit yield and quality. Pineapples which received fertilizer mixture of NPK 200-50-200 produced the highest and best quality fruits and was therefore recommended for optimum yield of pineapples in the tropical ferrallitic soils.  相似文献   

3.
Phosphorus management of a rice-wheat cropping system   总被引:1,自引:0,他引:1  
A long term field experiment was conducted on a sandy loam soil from 1983 to 1987 to determine how to best apply phosphorus fertilizer in a rice-wheat cropping system. The treatments included 9 combinations of phosphorus application either to both rice and wheat or to rice or wheat alone. Direct application of phosphorus at 13 kg/ha to both the crops resulted in significantly higher total productivity of the rice-wheat cropping system as compared with 26 kg P/ha applied either to rice or wheat alone. Phosphorus at 13 kg/ha for rice and 26 kg/ha for wheat was as efficient as 13 kg P/ha for rice and 13 kg P/ha for wheat. The higher rate of P (26 kg/ha) applied to both rice and wheat resulted a decline in the total productivity. The residual effects of phosphorus applied to either rice or wheat were significant to the succeeding crop but was inferior to its direct application. Phosphorus increased the leaf area index, chlorophyll content of leaves, and interception of more photosynthetically active radiation (PAR) which resulted in increased grain yield of rice and wheat. Phosphorus status of the surface soil declined markedly, in the absence of P application from 15.4 to 6.4 kg P/ha. Phosphorus applied at 26 kg P/ha to both the crops resulted a build up of the available P status of soil. Phosphorus application at 13 kg/ha to both rice and wheat maintained the phosphorus status of the soil at original level.  相似文献   

4.
Microplot experiments were conducted at two locations (Lacombe and Eckville) in central Alberta to evaluate methods of application of urea (60 kg N ha–1) on established meadow bromegrass (Bromus biebersteinii L. cv Regar). Urea was surface broadcast and banded 4 cm deep into soil at four row-spacings (15, 22.5, 30 and 37.5 cm). The dry matter and crude protein yield were generally greatest in plots when urea was banded at 15 cm spacing. There was a general decrease in dry matter yield, particularly with the first cut at the Lacombe site when urea was banded at more than 15 cm spacing. The dry matter yield, crude protein yield and crude protein concentration were significantly greater in grass adjacent to the banded fertilizer than in grass from the area midway between the bands at the Lacombe site.  相似文献   

5.
To evaluate alternative fertilizer phosphorus (P) sources in lowland rice, two field experiments were conducted under irrigated conditions in Quezon Province, Philippines during 1990–1991 crop year. In another field experiment fertilizer P recycling through a green manure crop applied in the succeeding rice, was studied. Addition of fertilizer P increased grain yield by 1.5–2.0 t/ha (46%) in 1990 wet season (WS) and by 1.6–2.1 t/ha (56%) in 1991 dry season (DS). However, fertilizer P source and application level did not effect grain yield significantly. Results indicated that the less water-soluble and less expensive partially acidulated phosphate rock (PAPR), phosphate rock (PR) and less reactive PR were as effective as the more soluble but more expensive triple superphosphate (TSP). The relative effectiveness (RE) of local guano was significantly lower than that of other sources of fertilizer P. Fertilizer P applied to a pre-rice Sesbania rostrata green manure increased rice grain yield by 1.5–1.9 t/ha during 1991 DS. Further, S. rostrata fertilized with Morocco phosphate rock (MPR) gave significantly higher rice grain yield than did rice fertilized with MPR applied alone. In the P source experiments Olsen method and Pi correlated better with growth attributes than Bray 2 P. Phoshours uptake did not differ significantly among P sources and levels. Results suggest that P uptake was improved with green manuring. Correlation analyses revealed a close correlation between P uptake and dry matter yield and P uptake and grain yield.  相似文献   

6.
In a fertilizer and manure experiment, millet was grown under four treatments (no fertilizer or manure, farmyard manure, chemical fertilizer, and both). Grain yield and total aboveground biomass production of the unfertilized plot were relatively high. The observed differences in total dry matter production must be attributed to differences in nutrient availability, as amount of rainfall and its distribution were favourable. Results show only small differences in distribution of dry matter among the various plant organs between the best and the non-fertilized treatments.Nutrient supply from natural sources, defined as crop content of N, P, and K at maturity without fertilizer application, amounted to 104, 16 and 103 kg ha–1, respectively, which are very high values.Total uptake of calcium and magnesium is related to that of potassium, as the combined content of these three elements is linearly related to total aboveground biomass production. Minimum removal of nitrogen and phosphorus per ton grain dry matter amounts to 29 and 4kg, respectively, and 9 kg potassium per ton total aboveground dry matter. A possible double function of phosphorus as element of structural biomass and for maintenance of electro-neutrality is discussed.  相似文献   

7.
An analysis of tuber roots yield and nutritional characteristics for 10 lines of jícama (Polymnia sonchifolia Poepp et Endl.) was carried out under the environmental conditions of Santa Catalina Experimental Station (12 degrees C of temperature and 3,100 m above sea level). The following average mean values were obtained: A fresh tuber root's yield from 29,755 to 73,558 kg/ha with 41,547 kg/ha of average, while the yield of the useful part (roots without skin) was from 24,309 to 60,097 kg/ha with 33,944 kg/ha of average. On the other hand, average mean values of 3.7% of protein, 3.5% ashes, 1.5% fat, 3.4% fiber, 2.2% potassium, 0.12% phosphorus, 96 micrograms/100 g iron, and 390 micrograms/100 g zinc, were obtained from the edible root samples. Besides, we obtained average values of 2.47, 2.12, 1.63 and 2.51 g/100 g of fructose, alfa glucose, beta glucose and saccharose, respectively, on edible root samples with skin, for the 10 lines studied. All these analyses were reported on a dry basis.  相似文献   

8.
Composition of Coconut Testa,Coconut Kernel and its Oil   总被引:1,自引:0,他引:1  
Testa, a by-product from the coconut processing industry is getting wasted. A study was carried out to utilize testa as a source of edible oil. The composition of the oils from testa of wet coconut (WCT) and copra (CT) were evaluated and compared with wet coconut whole, copra whole, wet coconut white kernel and copra white kernel. The samples had fat as a major component ranging from 34 to 63 %. Oils had 90–98.2 % triacylglycerols, 1–8 % diacylglycerols and 0.4–2 % monoacylglycerols. The triacylglycerol composition of oil from WCT had decreased trilaurin and increased triolein. Lauric acid content of CT was 40.9 % and WCT was 32.4 % whereas other oils were 50–53 %. Oils from testa were richer in monounsaturates and polyunsaturates than other coconut oil samples. The phenolics and phytosterols content were 0.2–1.9 % and 31–51 mg%, respectively. The total phenolic acids and tocopherol content of oils from CT (313.9 μg%, 22.3 mg%) and WCT (389.0 μg%, 100.1 mg%) were higher than other samples (94.8–291.4 μg%, 2.5–6.7 mg%). These studies indicated that the oil from coconut testa contained more of natural antioxidants such as tocopherols, tocotrienols and phenolics compared to coconut kernel oil and may confer health benefits.  相似文献   

9.
Six bread formulations were developed, using different proportions of whole-wheat flour, chia seeds and flaxseed flour. All of our formulations were added with folic acid. Sensorial and texture evaluations were performed, showing good acceptance of the products. Proximal chemical analysis was carried out; in addition, the following parameters were determined: calcium, phosphorus, total dietary fiber, folic acid, water hydration capacity, Glucose Dialysis Retardation Index (GDRI) and fatty acids. The results obtained showed higher protein levels in the developed breads (23.23-30.24 (g/100g dry matter) as compared to a control (21.00% of proteins in bread elaborated without chia or flaxseed). Furthermore, the breads contained 10.07-12.15 of lipids (g/100g dry matter) (linoleic acid: 2.43-4.05%; linolenic acid: 1.12-4.46 %; oleic acid: 2.93-6.13 %), GDRI values were between 89.1 and 98.1 % and folic acid was in the range 699.44 - 991.3 (microg/100g dry matter). The same parameters were determined in the chia seed and in the flaxseed flour. It was concluded that; due to their high levels of protein, insaturated fatty acids (omega-3 and omega-6), dietary fiber and folic acid, these breads have a high nutritional value, so they could have special benefits for woman.  相似文献   

10.
Rumex crispus L. seeds harvested in Olavarría (Province of Buenos Aires, Argentina) were extracted with 60–80°C petroleum ether to render 6.0% (dry basis) of a lipid fraction with a 152.4 saponification value and 15.4% unsaponifiable matter. Fatty acid composition obtained by gas-liquid chromatography was: 14:0, 2.7; 16:0, 13.5; 16:1, 1.2; 18:0, 1.2; 18:1, 38.6; 18:2, 36.3; 18:3, 0.5; 20:0, 2.4; 20:2, 0.3; 22:0, 0.9; 22:1, 1.2; and 24:0, 1.2; with traces of 14:1, 15:1, 17:0, and 17:1. Residual meal contained 10.62% crude protein, with a low value of available lysine (3.31 g/16 g N). Ash, crude fiber, sugars, hydrolyzable carbohydrates, total and phytic acid phosphorus, calcium and residual lipids contents are reported here.  相似文献   

11.
The chemical composition, content of antinutritional factors, and the in vitro protein digestibility of grains of the pseudo-cereal Amaranthus were analyzed. The plants were grown in Brazil (without fertilizer), Puerto Rico (100 kg N/ha), and California (200 kg N/ha). The seed analysis gave the following values (%DM): 14.4 - 16.9 protein (N X 6.25), 4.8 - 6.8 fat, 2.5 - 3.9 ash, and 2.3 - 2.9 crude fiber. The trypsin inhibitors, phenolics and saponine contents were low, and the phytohemagglutinin activity, fairly low. The in vitro protein digestibility was 61 - 76%. Digestibility was not correlated to the analyzed proximal composition nor to the antinutritional factors. The grain composition indicates a food value equivalent to that of conventional food grains.  相似文献   

12.
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   

13.
Two field experiments were conducted to compare the fertilizing and liming properties of dried lime-treated sewage sludge with its incineration product (ash). One experiment used a mixture of ryecorn and ryegrass on a relatively fertile soil and the other lucerne on a strongly acidic and phosphorus deficient soil.The first harvest of the ryecorn-ryegrass experiment showed small but significant linear responses in dry matter yield to both ash and sludge. Ash applications did not affect foliage nitrogen and phosphorus concentrations, or uptakes, but sludge applications increased these significantly. Sludge also increased the concentrations of K, S, Mg, Cu and Zn but ash only increased the concentrations of S and Mg. At the second harvest (ryegrass) 5 t ha–1 of sludge increased dry matter yield and foliage nitrogen and phosphorus concentrations whereas ash had no effect. Levels of phosphorus extracted from the soil were increased by both amendments but the sludge was much more effective than the ash. Both ash and sludge raised soil pH.In the lucerne experiment comparisons between sludge and ash were calculated from response surfaces fitted to the data which showed marked increased in soil pH and dry matter yield. Sludge markedly increased extractable phosphorus whereas ash had no effect. The sludge was 22% as effective as ash in raising soil pH to 6.5. The amounts of ash required to obtain the same yield as 10 t ha–1 of sludge were 5.78, 12.78 and 6.39 t ha–1 respectively for three successive harvests. These results and those for foliage concentrations of nitrogen and phosphorus were also ascribed to the much greater availability of the sludge phosphorus than the ash phosphorus, and the presence of nitrogen in the sludge but not in the ash.  相似文献   

14.
The investigation studied the effect of fertilization with four nitrogen levels (0, 100, 150 and 200 kg/ha), four potassium levels (0, 100, 150 and 200 kg/ha) and four irrigation treatments (0, 3, 7 and 14-day interval) on the growth and yield of smooth Cayenne pineapples. Increasing irrigation frequency increased growth parameters of number of leaves, D-leaf length and days to 50% flowering. Fruit weight was highest at N = 150 kg/ha, K = 200 kg/ ha and irrigation once a week. Higher N levels (beyond 150 kg/ha) applied after the plant crop has been harvested did not further enhance yields of the ratoon crop. For K = 200 kg/ha potential and harvested yields were reduced in all irrigation treatments when N > 150 kg/ha.  相似文献   

15.
The chemical composition of green seaweed, Monostroma undulatum, Wittrock, growing in the Southern Argentina coast, was studied. Samples were collected in Puerto Deseado, province of Santa Cruz (47 degrees 45'L.S., 65 degrees 55'L.W.), from October to December 1999 and 2000. It has been analyzed six sample during this period. Algae were washed with sea water and dried at room temperature for 24 hs. Moisture, nitrogen, lipids and ashes were determined according to AOAC; fiber (total, soluble and insoluble), according to Lahaye. After mineralization with nitric acid, sodium and potassium were determined by flame photometry, calcium by complexometric method, and phosphorus by Gomori's method. The ranges expressed per 100 g dry algae were: protein (Nx6.25): 12.89-21.85; ashes (g): 33.92-40.05; lipid (g): 0.32-1.47; total fiber (g): 14.36-19.6; digestible carbohydrates (calculated by difference) (g): 20.86-32.48; sodium (g): 7.39-13.11; potassium (g): 1.38-3.18; calcium (mg): 149-226; phosphorus (mg): 190-447; Vitamin C (mg): 159-455. These results show that this green seaweed is an important source for protein, fiber, macronutrients minerals and vitamin C, during the macroscopic period. There was an important fluctuation that must be taken into account to consider the commercial collection to use it in human nutrition.  相似文献   

16.
Long-term experiments have been undertaken to investigate the effects of various types of phosphorus fertilizers on yields, phosphorus uptake and fertilizer conversion in the soil. Optimum effects were obtained from water-soluble phosphate, whereas finely ground soft rock phosphate had little effect even with large amounts of phosphorus fertilizers and with a pH value of the soil of around 5.4. Partially decomposed and sintered phosphates performed well, as did NPK fertilizers (100% water soluble) and Thomas phosphate. The addition of large amounts of phosphorus fertilizers (to cereals, 26.4 kg/ha, to other crops 44 kg/ha) led to yields being increased by 7% and phosphorus extraction being increased by 11%. Smaller amounts of phosphorus fertilizers (13.2 and 17.6 kg/ha) did not have this effect. Increases in the amount of double-lactate-soluble phosphorus in the soil depended on the level of fertilization and did not differ significantly according to the type of phosphorus fertilizer used.  相似文献   

17.
针对冷冻法硝酸磷肥副产粗硝钙液中的磷进入滤渣难以回收利用导致硝酸磷肥装置产能低、胶磷矿富集技术浸取工段氨逃逸率低致使浸取液中硝酸铵含量高造成下游无法使用的问题,开展了粗硝钙液用于磷矿脱镁的研究。实验方法及最优反应条件:原矿经破碎、煅烧(煅烧温度为900~1 100 ℃,煅烧时间为1.5~3.0 h),用粗硝钙液浸取,利用粗硝钙液的热能和化学反应热控制反应温度为60~70 ℃(不需加热,节省了蒸汽消耗),反应pH为4.5~6.5,反应过程中无磷析出。在此条件下制取的磷精矿中五氧化二磷质量分数≥35%、氧化镁质量分数≤1.0%,磷回收率为100.49%~100.60%。将制取的磷精矿进行酸解,提高了酸不溶物的分离效率,可满足下游生产白色硝酸磷肥对原料的要求,副产的浸取液可用于生产氨基酸液体肥和中量元素营养母粒。该方法无尾矿产生,绿色环保,为磷矿的高效利用提供了新的研究思路。  相似文献   

18.
A glasshouse experiment was conducted to examine the comparative growth and P uptake response following P fertilizer application in lupins (Lupinus angustifolius L. cv. Chittick) and chickpeas (Cicer arietinum cv. Tyson) compared to wheat (Triticum aestivum cv. Sunstar). Measurements of dry matter, phosphorus uptake and nodule numbers were made at 50 and 100 days after sowing. At the 50 day harvest, the two legume crops produced less dry matter and accumulated less plant P than wheat but no such species interactions were present at the 100 day harvest. Chickpeas showed strong positive responses in nodule numbers with increasing rates of P fertilizer while such effects were less and more variable with lupins.  相似文献   

19.
Tropical varieties of sesame grown in California exhibit lush vegetative growth and could serve as sources of leaf protein concentrates. Green sesame plants were harvested in late August and, following 3 months of vegetative growth, produced 18.5 tons of fresh material per hectare, 543 kg/ha of protein. It is expected that these yields could be increased with breeding of better varieties and improvement of cultural practices. Amino acid composition of sesame leaves was comparable to alfalfa; 17 amino acids make up 21% of dry leaf weight.  相似文献   

20.
Twenty cassava cultivars (Manihot esculenta Crantz) were analyzed for fatty acids, nonstructural carbohydrates and crude protein contents. The main constituent fatty acids were myristic, palmitic, stearic, oleic, linoleic and linolenic. Trace amounts of lauric, myristoleic and palmitoleic acids were detected. Saturated acids ranged from 26.58 to 58.05%. Acid-digestible carbohydrates ranged from 11.82 to 40.70% of the green matter. Reducing and non-reducing soluble oligosaccharides also were determined. Crude protein ranged from 1.39 to 4.70% of the dry matter. Linear regression analyses were made, but no significant correlations were found. Some possible genetic relationships are proposed for certain cultivars.  相似文献   

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