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1.
[Objective] The historical evolution pattern of nitrogen (N), phosphorus (P) and potassium (K) fertilizer application rate and its effects on lint cotton yield were explored to provide the theoretical basis for reasonable fertilizer management strate-gy in the cotton planting region of the Yangtze River Val ey. [Method] GGE biplot analysis method was adopted to analyze the correlation among N, P and K fertilizer application rate and lint cotton yield with the dataset of national cotton regional trials of the Yangtze River Val ey during 1991-2013. The linear and nonlinear regression analysis method was used to reveal the evolution of the fertilizer applying patterns, and analyze the effects of N, P, K application rates on cotton lint yield. [Result] The application rates of N, P and K fertilizer presented highly significant positive corre-lation with lint cotton yield, among which the potassium fertilizer was the strongest relative factor with lint cotton yield, fol owed by phosphorus fertilizer, while nitrogen fertilizer was the weakest factor. The application rate of nitrogen fertilizer was relat-ed with the test year in the pattern of a quadratic function, while phosphate and potassium had progressive increase linear relation with the test year in the cotton planting region of the Yangtze River Val ey. Meanwhile, cotton lint yield was in re-sponse to nitrogen fertilizer content increase with a quadratic parabola function, and increased with the applying phosphate fertilizer and potassium fertilizer content with linearly increasing function. [Conclusion] The increasing application amount of N, P and K fertilizer was general y beneficial to cotton yield improvements, however, ex-orbitant applying nitrogen fertilizer was unfavorable for cotton production, and a reasonable mixture formula of N, P and K fertilizer was better in terms of cotton yield-increasing effect.  相似文献   

2.
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   

3.
[Objective] This study aimed to investigate the combination effects of ligustrazine and cis-dichlorodiamine platinum (DDP) on anti-proliferation, cell cycle and apoptosis of SGC-7901 cell lines in vitro. [Methed] SGC-7901 cells were treat- ed with ligustrazine and DDP alone or combined for 48 h for morphology assay. Anti-proliferative effects with the same treatment for 24, 48 and 72 h were assayed by MTT method, respectively. Cell cycle distribution and apoptosis assay of treated cells were performed in flow cytometry. Zhengjun Jin's protocol was used to assay the effect of drug combination. [Result] Ligustrazine significantly increased the prolif- eration inhibition rate of DDP on SGC-7901 cells in combination with DDP, com- paring with the effects of ligustrazine or DDP alone, and exhibited synergistic antitu- mor effect. The combination drug treatment induced cell cycle arrest occurred in S and G2 phase of the cell cycle and increased the apoptosis rate significantly. [Conclusion] Our results indicate that ligustrazine, as a low-toxic and natural herbal component, can significantly increase the anti-proliferative effect and apoptosis rate of antitumor drug DDP on human gastric carcinoma SGC:.-7901 cells.  相似文献   

4.
Spatio-temporal relationship of the phytophagons Clania miniscula (Butler) and garden spiders was examined through analysis of their niche and distribution as they occur in sasanqua orchard in Southern Anhui, China from June 2003 to May 2004. The dynamic relationships between Clania minuscula and garden spiders were seasonal in time and space. Spatio-temporal niche breadth was high for the two groups, ranging from 0.57 to 0.98; niche overlap was also high between the two groups from 0.76 to 0.96 during the seasons of June 2003 to May 2004. Geostatistical results indicated that Clania minuscula and garden spiders were aggregated during the emergence periods. The pest Clania minuscula was spatially dependent to a range from 33.48 to 46.84 m while spatial dependence from 30.93 to 51.11 m for garden spiders. The correlation analysis of distribution maps further illustrate the distribution of garden spiders always coincided with that of Clania minuscula. These results showed spatio-temporal synchrony of Clania minuscula and garden spiders at different periods. Adequate knowledge of spatio-temporal correlation between Clania minuscula and garden spiders contributed to provide information for biocontrol at different periods in sasanqua orchard.  相似文献   

5.
Lingwu Changzao (Ziziphus. jujube Mill) is a Ningxia local variety, it has a good table quality despite its short postharvest life. The respiration rate, the weight change of single fruit during growth development and the losing water of postharvest of fruit were studied. The results showed that the curve of fruit growth development was a double sigmoid characteristic. When the surface colour of fruit changed form jade-green to alizarin crimson, the respiration rate tended to fall during a entire growth development of fruit, which showed a fluctuation phenomenon. The respiration rate descended when the surface color changed from coloring to baby red, but after a crimson stage the respiration rate recurred to its original downtrend. With increasing of single fruit weight, phenomenon of respiration climacteric has not happened and the respiration rate curve showed a concavity characteristic at some stages. As a result, there was not a phenomenon of respiration climacteric with a double sigmoid growth development curve characteristic of fruit.  相似文献   

6.
[Objective] The aim was to study the molecular identification and cultivar fingerprints of Prunus persica (L.) Batsch germplasms.[Method] Sixty peach genotypes,representing China common local cultivars and European samples were screened by microsatellites (simple sequence repeats,SSRs) and Inter-Simple Sequence Repeat (ISSR) markers.[Result] 26 reproducible bands were amplified by Nine SSR primers,and 24 of which were polymorphic; 236 bands were amplified by 30 ISSR primers,and 113 of which were polymorphic.31 genotypes were discriminated with 1-3 distinct polymorphic bands generated from the primers ISSR and SSR.Seven cultivar-specific ISSR fragments and two SSR unique alleles obtained from this study were available to be converted into Sequence Characterized Amplified Region (SCAR) markers.The genetic similarity coefficient (GS) estimated from these molecular data averaged were 0.939 (ranged from 0.856 to 0.983) for ISSR and 0.646 (ranged from 0.240 to 1.000) for SSR,respectively.The combined grouping association indicated that most local Chinese peach cultivars and exotic accessions were clustered together.This could be related to the mode of introduction and maintenance of the peach cultivars involving limited foundation germplasm,exchange of cultivars between plantations,and periodic development of new recombinant cultivars following sexual reproduction.[Conclusion] The results obtained in this work would help to improve the conservation,molecular identification and management of peach germplasm in breeding.  相似文献   

7.
[Objective]The energy productivity potential of Saccharum spontaneum L.germplasm resources as energy plants was discussed in this paper.[Method]The energy productivity potential of Saccharum spontaneum L.germplasm resources collected from the wild was assessed from the aspects of cellulose,semicellulose,lignin and crude ash contents and caloric value.[Result]The total content of cellulose and semicellulose ranged from 41.75%to 69.13%,the lignin content ranged from 2.16%to 11.75%,the crude ash content ranged from 4.79%to 9.34%and the caloric value ranged from 16.00 to 17.69 MJ/kg among the 30 Saccharum spontaneum L.germplasms.Compared to other plants,Saccharum spontaneum L.had higher contents of cellulose and semicellulose,a higher caloric value but lower contents of lignin and crude ash.[Conclusion]From the perspective of producing fuel ethanol with lignocellulose,Saccharum spontaneum L.has a great potential for development as an energy plant.  相似文献   

8.
The use of the power tillers (walking tractors) are increasingly popular in Nigeria among farmers adopting Sawah rice production technology. This study compares the effects of two types of power tillers on physical properties of soil and rice yield. because soil properties determine to a large extents rice yield. Data on soil properties and rice yield were collected and subjected to t-test statistics. The results show that, significant differences exit for all the physical properties of soils rice yields from fields where the two power tiller were used with yields from rice field where SHAKTI was used was higher than KUBOTA. It is important that farmers using these models of power tillers for rice production should not only focus on the purchase cost of these power tillers but their overall efficiency in order to achieve the desired high level of yield.  相似文献   

9.
The purpose of this study is to elicit how investments in agricultural development and food security would safeguard the Virgin Islands (BVI) and the Caribbean, by extension, from future global crisis. History shows that agriculture played a significant role in the rise of civilization globally and was the main contributor to the Caribbean economy before the 1950's. Overall, it was determined that the BVI population, in general, is desirous of more investment opportunities within the agricultural sector, to assist with the alleviation of poverty at the national level, to advance economic development and trade across the region and to make sustainable development more attainable for the Caribbean, as a whole. To do this, agricultural development and food security must become the focal point of the BVI and other Caribbean economies. Accordingly, the paper recommends that investment within the agricultural sector be undertaken more aggressively across the region. The mixed research approach method was used to validate these claims.  相似文献   

10.
Magnetic field effects on different plant species have been subject of many studies in the last decade. Magnetic fields are known to induce changes in plant metabolism, growth and productivity. In this study, effect of magnetic field on date palm weight and water content has been investigated. Seedlings of date palm were treated with two types of magnetic fields in two separate experiments. In the first experiment, seedlings were treated with static magnetic field SMF using electromagnetic circuit set to produce three levels of magnetic field intensities 10, 50 and 100 mT for different durations (0, 30, 60, 120, 180 and 240 min). In the second experiment seedlings were treated with alternating magnetic field AMF, using magnetic resonance imaging providing 1500 mT for 0, 1, 5, 10 and 15 min. After two months of exposure, plants growth parameters (fresh, dry weights and water content for both leaves and roots) were recorded. The measurements revealed that leaf fresh, dry weight and water content increased significantly in response to SMF treatment. Similarly, roots fresh weight and water content were increased significantly; however roots dry weight increasing were insignificant. In the second experiment, AMF has affected plant growth all parameters were increased significantly. Measurements reached the highest level at 15 min of exposure. This study revealed that magnetic fields affect date palm growth parameters by increasing osmotic pressure and water potential which increase water absorption and enhance flesh weight.  相似文献   

11.
Insufficient N supply is an important constraint to productivity of lowland rice. Studies on N nutrition of rice cultivars with different durations representing the north western part of Indo-Gangetic Plains are scanty. A field experiment was conducted during kharif seasons of 2006 and 2007 at PAU, Ludhiana to assess the differences in grain yield and N utilization of three popular rice cultivars at varying N doses. Significant differences among genotypes were observed in grain yield, N uptake, N use efficiency and N utilization efficiency. The cultivar PAU-201 was found to be superior among all the tested genotypes. Total N uptake and grain N uptake was highest in cultivar PAU-201 followed by cultivars PR-115 and PR-113. On an average, the response to applied N for grain yield was observed upto 90 kg N ha1. Grain yield increased significantly up to 90 kg N hal in cultivars PR-115 and PAU-201 and up to 120 kg N ha1 in PR-113. Apparent recovery efficiency (ARE) and Partial factor productivity (PFPN) of N was significantly reduced at higher level of N (150 kg N hal). It was concluded that N uptake is predominant factor in grain yield formation and cultivars differ in NUE suggesting that it may be possible to develop cultivars that are efficient at low nutrient level or are capable of using N more efficiently when applied as fertilizer.  相似文献   

12.
In order to maintain the health and vigour and to sustain the productivity, a pruning experiment was conducted on four year old "Balwant" cultivar of aonla grown in laterite soil, planted at a spacing of 5m×5m. To find out the best pruning method, six levels of pruning was performed i.e., (1) Light judicious pruning, (2) Detopping of primary branches at 8 feet from ground level + removal of all secondary branches, (3) Detopping of primary branches at 8 feet from the ground level + removal of all secondary branches at 2 feet from the base of primary branches, (4) Detopping of primary branches at 8 feet from the ground level + removal of all secondary branches at 1 feet from the base of primary branches, (5) Light judicious pruning + Detopping of plant canopy of at 8 feet from the ground level, (6) No pruning (control). Results of three consecutive years of investigation revealed that light judicious pruning of thin, overlapping, criss-crossed, dead, unproductive and looping branches gave highest fruit yield in all the three years and resulted 64.4 percent yield increment over control when average of three years was considered. Severe pruning of primary and secondary branches caused drastic reduction of yield for two consecutive years after pruning. Judicious pruning helped to produce better sizeable and quality fruits.  相似文献   

13.
Maize-rice cropping systems are expanding in Bangladesh. Hybrid maize has increasing demand and value, particularly for poultry feed, while rice remains the traditional dominant starch staple food. Bangladesh maize yields (with average farm yields around 5.7 t·ha^-1) are among the highest found in Asia. Cool winter (Rabi) season maize followed by T. Aman (monsoon) rice is the major cropping system; however it is now becoming diversified with many other crops including potato. Financially, hybrid maize is far more profitable than boro (irrigated) rice, wheat, or most other competing winter season Rabi crops. Although maize is relatively problem-free in Bangladesh, some constraints are intensifying with increased concern over input supply and soil-related environmental sustainability. An array of new technologies for sustainable intensive maize production systems is emerging in Bangladesh and some are being promoted and adopted. Continued sustainability of hybrid maize production in Bangladesh depends on optimization of planting time, quality seed of appropriate hybrids, balanced use of nutrient inputs along with soil fertility conservation and other management, for which further research would be high priority.  相似文献   

14.
The impact on soil of applying sugarbeet vinasses (V) was analyzed through a field experiment in horticulture greenhouse, arranged in a 23 factorial design. Two levels of three independent variables--application of V, use of polyethylene cover (PC) on the soil. and soil depth (D)---on various dependent variables were studied. Vinasses favoured crop yield and reduced the number of Meloidogyne incognita juveniles in soil. The concentrations ofN. P and K increased with the interaction VxD, with PC also increasing N concentration. The amounts of humic acids and humin decreased with D; fulvic acid concentration increased with V, but decreased with the interaction VxPC. Soil physical factors were improved mainly with D and V. Aromaticity of humic acid-like fractions increased ~'itb V. In general, V showed significant effects mainly on the topsoil, suggesting low leaching risks. The results indicate that the levels of the independent factors improving a group of variables were not the same that those contributing to another group. Therefore, their best combination should be determined for each scenario to achieve optimum agroecological performance.  相似文献   

15.
There are mounting evidences that human consume significant quantities of resources and have a major impact on the environment. Some research indicates that since the 1980 s human demands on the biosphere have exceeded its regenerrative capacity. One way to solve this problem is to minimize the inappropriate exploitation from environment.This essay will focus on energy self-sustained project, which is a specific way to reduce energy requirements. Energy self-sustained project refers to that energy production is equal to the amount consumed. Three concepts are quoted in the following to assess whether the project achieve zero-energy or not. First, ecological footprint, which provides an indication of the human load on the biosphere, is utilized to measure the inputs and outputs of the bioregion, which is also beneficial for defining the potential energy. Another one is life cycle assessment, which evaluates environmental load that relates to the entire life periodic system of a product, is helpful to measure the products used in the energy self sustained project. In addition, net energy, and gross resource abundance, definitions for selection, or hierarchy of different energy resources, can evaluate the new energy resources in project.Geos Neighbourhood, located in colorado, was planned as the largest net-zero energy neighbourhood in the United States. To meet the energy self sustainability,earth and sun power completely sustain the community's energy needs, and replace all fossil fuels. Compared with the traditional communities, Geos Neighbourhood minimize the adverse impact on the environment. As tools for assessment,ecological footprint, life circle assessment, and net energy, are all used to analyse the planning and design principles in the neighbourhood. By the research, the design principles and energy use in Geos Neighbourhood will be re-examined that whether the zero energy project achieves the reduction of ecological footprint, and energy self sustainability. In addition, life circle assessment will re-examine the materials used in the community also. Finally, the concept of ‘net energy' will test solar energy and earth power which is the major energy used in Geos Neighbourhood.  相似文献   

16.
The experiment was conducted using a total of 1392 one-day-old, Cobb commercial male broilers to investigate the effects of a commercial probiotic addition in diet on growth, the development of the small intestine and microbial populations of broilers. Broilers were randomly allotted by BW to 1 of 6 replicate cages (29 chicks per cage) for each of 8 treatments in a randomized block design involving one factorial arrangement of treatments. Dietary treatments included the basal diet (including corn, soybean, rapeseed, cottonseed meal) added with 100 mg/kg antibiotic, 0%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25% or 0.3%. The experiment last 42 d and divided into the starter period (1-21 d) and the finisher period (22-42 d). The results showed that there were significant differences in broiler body weight (BW) (P〈0.001), average daily feed intake (ADFI) (P=0.033), relative length of the duodenum (P〈0.001), jejunum (P=0.008), ileum (P〈0.001) and the populations of lactobacillus (P〈0.001) and coliform (P〈0.001) in the rectum between the probiotics treatments and the control treatment only in the starter period of the trails. No significant differences were observed in intestinal morphology parameters in two periods of the experiment. Our results indicated that the probiotic was able to improve the performance of broiler chickens, and it was better in the starter period to be used than in the finisher period.  相似文献   

17.
The genetic relationships among oakleaf loquat (Eriobotrya prinoides), Daduhe loquat (Eriobotrya prinoides var. dadunensis) and common loquat (Eriobotrya japonica) were studied by RAPD and ISSR markers. The results showed that the similarity coefficient between oakleaf loquat and common loquat was minimal (0.6996 and 0.7219, respectively) and the similarity coefficient between oakleaf loquat and Daduhe loquat was maximal (0.8403 and 0.8211, respectively), while the similarity coefficient between Daduhe loquat and common loquat was always intermediate (0.7195 and 0.7219, respectively). The highest additivity was obtained when Daduhe loquat was regarded as the undetermined hybrid (44.9% and 45.8%, respectively). The specific bands of oakleaf loquat and common loquat were present in Daduhe loquat. Thus, it could be concluded that Daduhe loquat was a hybrid of oakleaf loquat and common loquat.  相似文献   

18.
Carrot (Daucus carom) is a valuable source of health promoting ingredients such as anthocyanin, carotenes, phenolic compounds etc. These substances are important to man as a source of pharmaceuticals, fragrance, agrochemicals as well as food additives and used for prevention of many chronic diseases. Since these activities may be correlated with the presence of antioxidant compounds, extract of carrot and carrot callus were evaluated for their anthocyanin, flavonoids and total phenolic content as well as total antioxidant activity. Anthocyanin content was measured by spectrophotometric method. Total phenols and flavonoids were analyzed according to the Folin-Ciocalteu method and total antioxidant activity was assessed by ferric reducing/antioxidant power (FRAP) assay. Anthocyanin, flavonoids and total phenolic content were estimated to be 9.36 mg%, 46.96 mg% and 57.01 mg% for callus and 6.82 mg%, 32.96 mg% and 42.69 mg% for carrot, respectively, on fresh weight basis. The total antioxidant activity for the callus and carrot was found to be 51.13 mg, 118.77 mg, 91.08 mg and 140.08 mg equivalent and 79.40 mg, 184.44 mg, 141.43 mg and 217.52 mg equivalent to gallic acid, vitamin C, butylated hydroxyanisole (BHA) and trolox, respectively, when expressed per 100 g on fresh weight basis. The antioxidant activity of fresh carrot was found to be higher compared to its callus.  相似文献   

19.
Plant stress caused by exposure to magnetic fields (MF) induces modifications at molecular level, particularly in DNA synthesis, structure, and function. The objective of this study was to determine the effect of various doses of non-ionizing radiation of magnetic field on date palm (Phoenix dactylifera L.) based on DNA content. Date palm seedlings (cv. Khalas) established for 2 weeks on filter paper were subjected to static magnetic field and alternating magnetic field. Static magnetic fields (SMF) were applied at 10, 50 and 100 mT for 30, 60, 120, 180, 240 and 360 min; while alternating magnetic field applied by magnetic resonance imaging (MRI) at 1500 mT for 1, 5, 10 and 15 min. The seedlings were grown in potting soil following exposure for 4 weeks after which DNA was extracted from leaves and its content was determined. Generally, the exposure to magnetic field caused reduction in the content of DNA. The lowest exposure time tested, 30 rain, was sufficient to induce reduction in DNA content. This was true even at the lowest intensity, 10 mT. This dosage caused the DNA content to decrease from 49 ~tg/g to 45 pg/g. Further, increase of the exposure duration to 60 min caused significant reduction in the DNA content, 36 μg/g. At intensities higher than 10 mT, DNA content decreased significantly even at the shortest exposure of 30 min. At 50 and 100 mT, significant decrease in DNA content was also noticed in response to 30 min exposure; whereas the level of DNA increased after 1 min of MRI exposure to 52 ~g/g, then decreased after 5 min to 46 ~g/g. However, longer durations caused no further decrease in the DNA content. These observations indicate that magnetic fields interact with DNA processes, probably by inhibiting synthesis or stimulating degradation of DNA. This response merits further exploration as a mutational agent for date palm genetic manipulation.  相似文献   

20.
A field experiment was conducted for intercropped winter wheat (Triticum aestivum) in 2002/2003 to evaluate the effects of limited supplemental irrigation on photosynthetic characteristics of intercropped winter wheat in semiarid environment. The result indicated that significances occurred in grain yield between the intercropped wheat treatments and sole wheat control (CKW), and in yield between the irrigated intercropped wheat plots (WC2W, WC3W, WC5W) and not irrigated (WC1W) except for WC4W plots with nearly the same yield as WC1W. In comparison with CKW, 11.8%, 18.5%, 23.6%, 11.5%, and 30.7% of yield increase in the intercropped wheat plots were obtained in WCIW, WC2W, WC3W, WC4W, and WC5W respectively. Compared to the intercropped wheat plots without irrigation, yields in WC2W, WC3W, and WC5W were improved by 5.9%, 10.5%, and 16.9%, respectively. The dynamics of CGR and NAR in both intercropped (WC1W-WC5W) and solely cropped wheat (CKW) showed a type of "single peak" curves, with both the maximum CGR and NAR occurred during jointing to heading (14/4-6/5) of wheat. In addition, soil water potential (SWP) fluctuated as a function of the precipitation and limited supplemental irrigation.  相似文献   

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