A study was conducted in Côte d’Ivoire to assess the after-effect of phosphate amendments on rice yields and soil properties. Eight types of amendments, composed of Moroccan phosphate rock (PRM) and triple super...A study was conducted in Côte d’Ivoire to assess the after-effect of phosphate amendments on rice yields and soil properties. Eight types of amendments, composed of Moroccan phosphate rock (PRM) and triple superphosphate were tested in three agroecological zones over three consecutive years of cultivation. This study revealed that the application of Moroccan phosphate rock (PRM) and/or triple superphosphate (TSP) did not significantly affect soil cation exchange capacity (CEC) and organic carbon (Corg) content. However, there was a negative residual effect of PRM-rich treatments on soil pH and K and N content, but the impact varies depending on the characteristics of the soils studied. Furthermore, nutrient losses, notably nitrogen from −17.5 to −267.7 kg/ha and potassium (−0.1 to 0.7 kg/ha), were observed in all treatments. Only phosphorus showed a positive balance of +49.56 to +52 kg/ha in PRM-rich treatments. Treatment T3, composed of 80% RPM and 20% TSP, was the most effective in all zones, with a relative increase in grain yields of over 100% compared to the control. These results suggest that the input of natural phosphate rock can significantly improve rice yields and soil properties in the studied agroecological zones in Côte d’Ivoire.展开更多
To evaluate the effects of different conservation tillage modes on crop yield in various ecological regions, we interviewed peasant households in the Northeast China Plain, North China Plain, Chengdu Plain, and Northw...To evaluate the effects of different conservation tillage modes on crop yield in various ecological regions, we interviewed peasant households in the Northeast China Plain, North China Plain, Chengdu Plain, and Northwest China Oasis, China, to analyze the influencing factors of the tillage methods on crop yield. An index set was determined from seven yield parameters based on expert consultation and relevant literature. A comprehensive evaluation of conservation tillage methods in the various ecological regions was carried out using fuzzy theory. The approaches with the highest scores were identified for each region: wide and narrow rotation planting with high stubble standing retention in the Northeast China Plain; seeding after rotary tilled of wheat under corn straw mulching and no-tillage seeding of corn and other crops under wheat straw mulching in the North China Plain; no tillage with high stubble retention in the Northwest China Oasis; and no-tillage seeding of wheat and other crops under rice straw mulching in Chengdu Plain. These research data provide a useful guide for the selection of conservation tillage methods for optimum yields in different regions of China.展开更多
Mechanized direct sowing of rapeseed is a labor-saving and highly-efficient culture technique. In order to explore high-yield cultivation techniques suitable for Chengdu Plain, effects of several key agronomic measure...Mechanized direct sowing of rapeseed is a labor-saving and highly-efficient culture technique. In order to explore high-yield cultivation techniques suitable for Chengdu Plain, effects of several key agronomic measures', such as sowing date, density and N fertilizers, on development and yield formation were studied by strip and split plot experiment of three factors. The research showed that optimal condi- tions for direct seeding technology can be achieved provided with scientific sowing date, density and appropriate N fertilizers, and the research showed that rapeseed yield reached the peak at 320 g/m2, when sowing date was on September 3th, sow- ing density was 30 plant/m2, and nitrogen fertilizer was 27 g/m2.展开更多
In order to study the effect of salts stress on the growth and yield of wheat (cv. Inqalab), a pot experiment was conducted in the wire-house of the Department of Soil Science, Sindh Agriculture University Tando Jam. ...In order to study the effect of salts stress on the growth and yield of wheat (cv. Inqalab), a pot experiment was conducted in the wire-house of the Department of Soil Science, Sindh Agriculture University Tando Jam. The soil was artificially salinized to a range of salinity levels i.e . EC 2.16, 4.0, 6.0, 8.0 and 10.0 dS·m<sup>-1</sup> with different salts (MgCl<sub>2</sub> + CaCl<sub>2</sub> + Na<sub>2</sub>SO<sub>4</sub>). The salinized soil used for the experiment was sandy clay in texture, alkaline in reaction (pH > 7.0) and moderate in organic matter (0.95%) content. The results showed that with increasing salinity there was an increase in the ECe, Na<sup>+</sup>, Ca<sup>2+</sup>, Mg<sup>2+</sup> and Cl<sup>-</sup> and decrease in the K<sup>+</sup>, SAR and ESP values of the soil Increasing salinity, progressively decreased plant height, spike length, number of spikelets spike<sup>-1</sup> 1000 grain weight and yield (straw and grain). Adverse effects of salts on plants were associated with the accumulation of less K<sup>+</sup> and more Na<sup>+</sup> and Cl<sup>-</sup> in their flag leaf sap, grains and straw. This resulted in lower K<sup>+</sup>:5Na<sup>+</sup> ratio in flag leaf sap, grains and straw of wheat plants. These results indicated that the effects of salts stress were greater at 10 than at 8, 6 and 4 EC dS·m<sup>-1</sup>.展开更多
The effect of chemical reaction on free convection heat and mass transfer for a non-Newtonian power law fluid over a vertical flat plate embedded in a fluid-saturated porous medium has been studied in the presence of ...The effect of chemical reaction on free convection heat and mass transfer for a non-Newtonian power law fluid over a vertical flat plate embedded in a fluid-saturated porous medium has been studied in the presence of the yield stress and the Soret effect. The governing boundary layer equations and boundary conditions are cast into a dimen- sionless form by similarity transformations, and the resulting system of equations is solved by a finite difference method. The results are preSented and discussed for concentration profiles, as well as the Nusselt number and the Sherwood number for various values of the parameters, which govern the problem. The results obtained show that the flow field is influenced appreciably by the presence of the chemical reaction parameter γ the order of.the chemical reaction parameter m, the Soret number St, the buoyancy ratio N, the Lewis number Le, and the dimensionless rheological parameter Ω.展开更多
In order to provide scientific basis for rational fertilization of maize under different soil quality and fertility,the effect of combined application of NPK on yield and fertilizer effect of different maize varieties...In order to provide scientific basis for rational fertilization of maize under different soil quality and fertility,the effect of combined application of NPK on yield and fertilizer effect of different maize varieties was studied by using "3414" experimental design scheme in this paper. The results showed that there were significant differences in ear length,ear diameter,barren ear tip length,kernel number per spike,kernel weight and yield among different fertilization treatments. Fertilization can improve the agronomic characters of maize and increase the yield.The yield increase of maize in two experimental plots( MHQ and HZY) was 11. 0%-64. 3% and 0. 2%-61. 9%,respectively. There was obvious interaction effect among nitrogen,phosphorus and potassium fertilizers,the yield of maize was the highest at the level of medium nitrogen,medium phosphorus and medium potassium fertilization,and the fertilizer effect was in the order of N > P_2O_5> K_2O. The results of curve fitting showed that the recommended application rates of N,P2_O_5 and K_2O in MHQ plot were 373. 7,74. 8 and 79. 9 kg/ha,respectively; the recommended application rates of N,P_2O_5 and K_2O in HZY plot were 419. 7,75 and 75 kg/ha,respectively.展开更多
Experiments were conducted to study the effects of density on growth and biomass partitioning of Leucaena leucocephala seedlings.Four plantations with densities of 10,000,20,000,40,000,and 80,000 seedlings ha^-1 were ...Experiments were conducted to study the effects of density on growth and biomass partitioning of Leucaena leucocephala seedlings.Four plantations with densities of 10,000,20,000,40,000,and 80,000 seedlings ha^-1 were evaluated only from 15 to 25 months after planting.At 15 months,crown height and width decreased with increasing density.Seedling height/dbh ratios increased with increasing density.Biomass increased with greater density according to the yield–density effect equation,which was evident for all densities.With increasing age,biomass division to branches and leaves increased,whereas partitioning to roots decreased in the 10,000 and 20,000 seedlings ha-1 plantings.Partitioning to branches and leaves remained relatively steady,while partitioning to roots increased in the 40,000 and 80,000 seedlings ha^-1 plantings.Biomass division into stem and bark components remained relatively steady in all densities.Yield–density and organ yield–density curves shifted upward with increasing seedling age on a log–log graph throughout the experimental period.展开更多
Soybean cultivar Bei 92-28 was tested in this experiment in 2000 to study the coupling effect of water and ferilizer on soybean yield.The results showed that the effect of irrigation varied among the levels of fertili...Soybean cultivar Bei 92-28 was tested in this experiment in 2000 to study the coupling effect of water and ferilizer on soybean yield.The results showed that the effect of irrigation varied among the levels of fertilizer application,and vice versa;pods per plant,seeds per pod.and 100-seed weight had positive correlations with soybean yield,but the degrees of correlations of different treatments were various;LAI and dry matter accumulation could be significantly increased when watered and applied fertilizer with different levels,but high fertilizer application treatment didn't obtain the highest yield;watering could increase the absolute absorption amount of N,P,K in seeds,but the accumulation rates were various.展开更多
[Objectives] This study was conducted to further explore the yield increasing potential of Codonopsis pilosula, and to seek seedlings suitable for efficient production of C. pilosula. [Methods] The effects of C. pilos...[Objectives] This study was conducted to further explore the yield increasing potential of Codonopsis pilosula, and to seek seedlings suitable for efficient production of C. pilosula. [Methods] The effects of C. pilosula seedlings of different sizes on root yield and commercial quality under different cultivation densities were studied. [Results] The fourth-grade seedlings had the least input, the highest yield of 6 948 kg/hm^2, the largest output-to-input ratio at 18.3, the highest root weight proportion of the second-grade product at 58.1%, and the lowest root weight proportion of the first-grade product at 17.6%. Considering the yield, quality and economic benefits comprehensively, the treatment of the fourth-grade seedlings(seedling diameter≤4 mm) is the best choice, and the suitable plant spacing is 8 cm×22 cm. [Conclusions] The study provided a reference basis for the cost saving and efficiency improvement of C. pilosula production.展开更多
Two genetic linkage maps, constructed by DH and RILs populations derived from the same parents, were carried out for the identification and comparison of QTLs controlling yield traits across different years in rice (...Two genetic linkage maps, constructed by DH and RILs populations derived from the same parents, were carried out for the identification and comparison of QTLs controlling yield traits across different years in rice (Oryza sativa L.). A total of 194 SSR and STS markers were used in two maps, of which 114 markers were same. The distribution of Samgang allele was higher in RILs population than it in DH population. Comparing with DH population, RILs population has more lines with higher yield and wider phenotypic transgressive segression for yield traits. Although most of QTLs for the same trait were different in two populations across different years, 8 QTLs (including gwp 11.1, spp5.1, spp 10.1, spp 11.2, ssrl. 1, ssrl 1.1, tgw9.1 and tgwl 1.1) were detected over 2 yr. It is important to note that pppl0.1, sppl0.1 and tgw9.1 were identified in two populations, while sppl 0.1 and tgw9.1 were simultaneity observed across different years. Epistatic effects were more important than additive effects for PPP, SPP, yield in DH population and TGW, yield in R/Ls population. Epistatic effects of DH and RILs populations were different on the same genetic background in the present study, which illuminated the QE interaction played an important role on epistatic effect. Identification and comparison of QTLs for yield traits in DH and RILs populations should provide various and more precise information. The QTLs identified in present study would be valuable in marker-assisted selection program for improving rice yield.展开更多
In order to study the effect of 30% Tiange multifunctional pesticide-fertilizer on sugarcane pests and sugarcane yield,the field test was conducted with conventional compound fertilizer and 3% carbofuran fertilizer gr...In order to study the effect of 30% Tiange multifunctional pesticide-fertilizer on sugarcane pests and sugarcane yield,the field test was conducted with conventional compound fertilizer and 3% carbofuran fertilizer granules as control. The results showed that 30% Tiange multifunctional pesticide-fertilizer could effectively suppress some pests such as sugarcane borer,thrip,aphid and cockchafer. 90 d after pesticide-fertilizer application,the sugarcane withered heart rate was 1. 55% and 2. 55% in the two test points,respectively,significantly lower than the rate of 15. 40% and 19. 40% under control. Before harvest,the sugarcane borer damage rate in the two test points under pesticide-fertilizer treatment was 8. 70% and 9. 47%,respectively,significantly lower than the rate of 34. 50% and 33. 50% under control,and the sugarcane yield was 21. 16% and 22. 14% higher than under control,respectively. 30% Tiange multifunctional pesticide-fertilizer had nutritional and insecticidal effect,which could help to achieve sugarcane pesticide-fertilizer integration and save labor and costs.展开更多
This work is concerned with the estimation from the outside of effective yield strength for the stage II consolidated material package of axisymmetric solid particles. Once an appropriate simple representative axisymm...This work is concerned with the estimation from the outside of effective yield strength for the stage II consolidated material package of axisymmetric solid particles. Once an appropriate simple representative axisymmetric unit cell is chosen, the kinematical approach of the yield design homogenization method is used in order to obtain external estimates which has been found depending on the loading history (isostatic and closed die compactions) as well as on the relative density of the material powder. For comparison purpose, finite element simulations that describe the behavior of spherical elastic plastic particles uniformly distributed inside the material powder are carried out.展开更多
According to the analysis of 654 soil samples collected from 45 counties in Zhejiang Provence, 73.7% of paddy field showed Si deficient. During 1991 and 1993, in Lishi, Longquang, Qingtian and Tonglu Counties, field e...According to the analysis of 654 soil samples collected from 45 counties in Zhejiang Provence, 73.7% of paddy field showed Si deficient. During 1991 and 1993, in Lishi, Longquang, Qingtian and Tonglu Counties, field experiments were conducted to test the effects of basal or additional Si-fertilizer on rice. Si-fertilizer was produced by Nanjing Inorganic Chemical Manufacture, containing 50% water solu展开更多
Field experiments were conducted to determine the effect of composts prepared from different organic materials with rock phosphate (RP) on yield and P uptake of berseem and their residual effect on maize crop (cv. Aza...Field experiments were conducted to determine the effect of composts prepared from different organic materials with rock phosphate (RP) on yield and P uptake of berseem and their residual effect on maize crop (cv. Azam) during 2011-2012. Composts prepared from RP fed farm yard manure (FYM), simple FYM, organic waste and city garbage were applied at the rate based on their P concentrations. Composts significantly (P ≤ 0.05) increased total dry matter weight of Berseem in first and second cut over control. Residual effect of the prepared composts was determined on yield and plant P uptake of maize in the same layout of Berseem. Maximum and significantly (P ≤ 0.05) higher maize grain yield, total dry matter yield and stover yield of 3161 kg·ha-1, 9633 kg·ha-1 and 6472 kg·ha-1, respectively were recorded by the residual effect of compost of organic waste with half dose of SSP. Thousand grains weight of 220 g was noted in the treatment of residual effect of compost of RP fed FYM with half dose of SSP. Post harvest soil N and P concentrations improved with composting. Significant (P ≤ 0.05) increases in N and P uptake by berseem and maize plants were observed with added composts. Results suggest that the use of composts prepared from different organic materials with RP is environmental friendly and has potential to improve crops yield and plants N and P uptakes for a prolonged time.展开更多
A field experiment was conducted to examine the residual influence of biochar applied previously to an established experiment at the Agriculture University Research Farm, Peshawar on soil properties and yield of maize...A field experiment was conducted to examine the residual influence of biochar applied previously to an established experiment at the Agriculture University Research Farm, Peshawar on soil properties and yield of maize crop during summer 2016. The experiment was established in RCB design with split plot arrangements having cropping systems (CS) in main plots and biochar (BC) in sub-plots. Cropping systems were: 1) wheat-mung bean;2) wheat-maize;3) chickpea-maize;and 4) chickpea-mung bean. During the past three seasons, each cropping system received biochar at 0, 40, 60 and 80 t·haǃ along with recommended dose of NPK in each season. For this study, maize was planted after chickpea and wheat in summer 2016. The results showed that grain yield, cobs weight and total N uptake of maize was significantly greater for chickpea-maize than for wheat-maize cropping system. Soil organic C was also significantly higher in soil under chickpea-maize than under wheat-maize cropping system. However, other yield components such as stover yield, harvest index and N concentration in grain and stover of maize and soil properties such as pH, EC and mineral N were non-significantly affected by cropping systems. With respect to residual effect of biochar grain yield of maize and bulk density of soil were maximum for treatment receiving biochar at 40 t·haǃ whereas cobs weight soil pH and mineral N were highest receiving biochar at 60 t·haǃ. Moreover, N concentration in stover, N uptake and soil organic C were maximum for treatment receiving biochar at 80 t·haǃ. However, stover yield, harvest index, N concentration in grain, and soil EC were non-significantly affected by biochar treatments. However interactions between CS × BC were significant for yield and yield parameters of maize and for soil properties (bulk density mineral N), while non-significant for harvest index, soil organic C, pH and EC. It was concluded that chickpea-maize cropping system performed better in terms of improving yield and yield components of maize and in improving soil properties. Application of biochar to previous crops also improved yield and yield parameters of the following maize as well as soil properties. Thus we recommend that legumes must be involved in cropping system for sustainable and higher productivity and improved soil properties. However, further studies are suggested to find out suitable dose of biochar for sustainable and economic crop productivity and soil fertility.展开更多
Salinity is the major limiting factor for forage productivity in southwestern coastal region of Bangladesh. Some introduced forage cultivars have been shown promising adaptability in saline conditions. The objective o...Salinity is the major limiting factor for forage productivity in southwestern coastal region of Bangladesh. Some introduced forage cultivars have been shown promising adaptability in saline conditions. The objective of this study was to assess the productivity and measure the agronomic characteristics of several introduced grass species with different created soil salinity levels. This study was conducted at the net house of Dr. Purnendu Gain Field Laboratory, Agrotechnology Discipline, and Khulna University during the period from December 2017 to February 2018. The experiment was laid out in a factorial randomized complete block design with seven replications. The experiment consisted of two factor viz. soil salinity levels (S<sub>1</sub> = 0.48, S<sub>2</sub> = 5.8, S<sub>3</sub> = 7.9, S<sub>4</sub> = 9.4, S<sub>5</sub> = 15 d<span style="white-space:nowrap;">·</span>Sm<sup><span style="white-space:nowrap;">−</span>1</sup>) and thirteen forage genotypes. Salinity levels and forage genotypes significantly (p < 0.05) influence all the growth parameters and biomass yield. The growth parameters and yield gradually decreased with the advance of soil salinity level. The tallest plant height (109.85 cm) was found in S<sub>1</sub> at 90 DAS while the shortest plant (24.53 cm) was obtained in S<sub>5</sub> at 90 DAS. Soil salinity had a significant difference (p < 0.001) on plant height at 90 DAS. The highest numbers of tillers (3.36) were found in S<sub>1</sub>, whereas the lowest (0.48) was in S<sub>5</sub> at 75 DAS. Soil salinity had a significant difference (p < 0.001) on Number of tillers at 75 DAS. The highest biomass wt. (29.14 g) was found in S<sub>1</sub>, while the lowest biomass wt. (3.52 g) was obtained in S<sub>5</sub> at 60 DAS. Soil salinity had a significant difference (p < 0.001) on biomass wt. at 60 DAS. The highest dry matter% (DM%) (21.24%) was found in S<sub>4</sub>, while the lowest DM (18.74%) was obtained in S<sub>1</sub> at 60 DAS. Soil salinity had a significant difference (p < 0.001) on dry matter% (DM%) wt. at 90 DAS. The tallest plant height (81.93 cm) was found in Pakchong, while the shortest plant (20.13 cm) was obtained in Endropogan at 60DAS. Soil salinity had a significant difference (p < 0.001) on plant height at 60 DAS. The highest numbers of tillers (3.07) were also found in Napier-3, whereas the lowest (0.80) was in H. Jaumbo at 75 DAS (S<sub>1</sub> + S<sub>2</sub> + S<sub>3</sub> + S<sub>4</sub> + S<sub>5</sub>). Soil salinity had a significant difference (p < 0.001) on Number of tillers at 75 DAS. The highest biomass wt. (38.60 g) was found in Pakchong, while the lowest biomass wt. (4.49 g) was obtained in Oats at 60 DAS. Soil salinity had a significant difference (p < 0.001) on biomass wt. at 60 DAS (S<sub>1</sub> + S<sub>2</sub> + S<sub>3</sub> + S<sub>4</sub> + S<sub>5</sub>). The highest (DM%) was found in Endropogan (24.68%), while the lowest DM (18.37%) was obtained Spelindida. Soil salinity had a significant difference (p < 0.001) on DM at 90 DAS. It can be concluded that Pakchong appears to be highly salt tolerant.展开更多
A pot experiment was conducted to investigate the effect of coconut peat on growth and yield response of Ipomoea aquatica for Pirojpur soil series during the period of 24th May to 25th June, 2017. The experiment was l...A pot experiment was conducted to investigate the effect of coconut peat on growth and yield response of Ipomoea aquatica for Pirojpur soil series during the period of 24th May to 25th June, 2017. The experiment was laid to fit a completely randomized design (CRD) with five treatments [control (T0), 1000 kg coconut peat ha-1 (T1), 1500 kg coconut peat ha-1 (T2), 2000 kg coconut peat ha-1 (T3) and 2500 kg coconut peat ha-1 (T4)] each having three replications for this experiment. After plant harvesting, the laboratory investigation was carried out in the Soil, Water and Environment Discipline, Khulna University, Khulna, Bangladesh. Yield contributing characters like number of leaves, fresh weight and dry weight were significantly (P < 0.05) influenced by different treatments. By contrast root length and shoot length were insignificantly varied compared to control (T0) treatment but from the eye observation and analytical data confirm increasing trend for the application of coconut peat. Among the five treatments applied T4 treatment (2500 kg coconut peat ha-1) has shown highest response to plant growth due to nutrient availability of the soil. The sequence of response was in the order T4 > T3 > T2 > T1 > T0 and significantly (P 0).展开更多
The ecological and physiological water require-ment of rice and rice yield was studied underthree irrigation patterns, which were A: moistirrigation, remains 70-90% of saturated soilwater content except 3-4 cm deep wa...The ecological and physiological water require-ment of rice and rice yield was studied underthree irrigation patterns, which were A: moistirrigation, remains 70-90% of saturated soilwater content except 3-4 cm deep water layerin tillering stage in paddy; B: flood irrigation,remains 4-5 cm deep water layer except 80%relative water content in the late tillering stage展开更多
文摘A study was conducted in Côte d’Ivoire to assess the after-effect of phosphate amendments on rice yields and soil properties. Eight types of amendments, composed of Moroccan phosphate rock (PRM) and triple superphosphate were tested in three agroecological zones over three consecutive years of cultivation. This study revealed that the application of Moroccan phosphate rock (PRM) and/or triple superphosphate (TSP) did not significantly affect soil cation exchange capacity (CEC) and organic carbon (Corg) content. However, there was a negative residual effect of PRM-rich treatments on soil pH and K and N content, but the impact varies depending on the characteristics of the soils studied. Furthermore, nutrient losses, notably nitrogen from −17.5 to −267.7 kg/ha and potassium (−0.1 to 0.7 kg/ha), were observed in all treatments. Only phosphorus showed a positive balance of +49.56 to +52 kg/ha in PRM-rich treatments. Treatment T3, composed of 80% RPM and 20% TSP, was the most effective in all zones, with a relative increase in grain yields of over 100% compared to the control. These results suggest that the input of natural phosphate rock can significantly improve rice yields and soil properties in the studied agroecological zones in Côte d’Ivoire.
基金funded by the Achievements Trans- form of Agricultural Science and Technology, Chinathe Extension of Major Production Technology of Advantageous Agricultural Productions from Ministry of Agriculture, China
文摘To evaluate the effects of different conservation tillage modes on crop yield in various ecological regions, we interviewed peasant households in the Northeast China Plain, North China Plain, Chengdu Plain, and Northwest China Oasis, China, to analyze the influencing factors of the tillage methods on crop yield. An index set was determined from seven yield parameters based on expert consultation and relevant literature. A comprehensive evaluation of conservation tillage methods in the various ecological regions was carried out using fuzzy theory. The approaches with the highest scores were identified for each region: wide and narrow rotation planting with high stubble standing retention in the Northeast China Plain; seeding after rotary tilled of wheat under corn straw mulching and no-tillage seeding of corn and other crops under wheat straw mulching in the North China Plain; no tillage with high stubble retention in the Northwest China Oasis; and no-tillage seeding of wheat and other crops under rice straw mulching in Chengdu Plain. These research data provide a useful guide for the selection of conservation tillage methods for optimum yields in different regions of China.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(200903050-4)National Public Science and Technology Research Funds Project(201303129)~~
文摘Mechanized direct sowing of rapeseed is a labor-saving and highly-efficient culture technique. In order to explore high-yield cultivation techniques suitable for Chengdu Plain, effects of several key agronomic measures', such as sowing date, density and N fertilizers, on development and yield formation were studied by strip and split plot experiment of three factors. The research showed that optimal condi- tions for direct seeding technology can be achieved provided with scientific sowing date, density and appropriate N fertilizers, and the research showed that rapeseed yield reached the peak at 320 g/m2, when sowing date was on September 3th, sow- ing density was 30 plant/m2, and nitrogen fertilizer was 27 g/m2.
文摘In order to study the effect of salts stress on the growth and yield of wheat (cv. Inqalab), a pot experiment was conducted in the wire-house of the Department of Soil Science, Sindh Agriculture University Tando Jam. The soil was artificially salinized to a range of salinity levels i.e . EC 2.16, 4.0, 6.0, 8.0 and 10.0 dS·m<sup>-1</sup> with different salts (MgCl<sub>2</sub> + CaCl<sub>2</sub> + Na<sub>2</sub>SO<sub>4</sub>). The salinized soil used for the experiment was sandy clay in texture, alkaline in reaction (pH > 7.0) and moderate in organic matter (0.95%) content. The results showed that with increasing salinity there was an increase in the ECe, Na<sup>+</sup>, Ca<sup>2+</sup>, Mg<sup>2+</sup> and Cl<sup>-</sup> and decrease in the K<sup>+</sup>, SAR and ESP values of the soil Increasing salinity, progressively decreased plant height, spike length, number of spikelets spike<sup>-1</sup> 1000 grain weight and yield (straw and grain). Adverse effects of salts on plants were associated with the accumulation of less K<sup>+</sup> and more Na<sup>+</sup> and Cl<sup>-</sup> in their flag leaf sap, grains and straw. This resulted in lower K<sup>+</sup>:5Na<sup>+</sup> ratio in flag leaf sap, grains and straw of wheat plants. These results indicated that the effects of salts stress were greater at 10 than at 8, 6 and 4 EC dS·m<sup>-1</sup>.
文摘The effect of chemical reaction on free convection heat and mass transfer for a non-Newtonian power law fluid over a vertical flat plate embedded in a fluid-saturated porous medium has been studied in the presence of the yield stress and the Soret effect. The governing boundary layer equations and boundary conditions are cast into a dimen- sionless form by similarity transformations, and the resulting system of equations is solved by a finite difference method. The results are preSented and discussed for concentration profiles, as well as the Nusselt number and the Sherwood number for various values of the parameters, which govern the problem. The results obtained show that the flow field is influenced appreciably by the presence of the chemical reaction parameter γ the order of.the chemical reaction parameter m, the Soret number St, the buoyancy ratio N, the Lewis number Le, and the dimensionless rheological parameter Ω.
基金Supported by Key Project of Yunnan Provincial Science and Technology Plan (2015FA022)Public Welfare Industry Special Scientific Research (201103003)
文摘In order to provide scientific basis for rational fertilization of maize under different soil quality and fertility,the effect of combined application of NPK on yield and fertilizer effect of different maize varieties was studied by using "3414" experimental design scheme in this paper. The results showed that there were significant differences in ear length,ear diameter,barren ear tip length,kernel number per spike,kernel weight and yield among different fertilization treatments. Fertilization can improve the agronomic characters of maize and increase the yield.The yield increase of maize in two experimental plots( MHQ and HZY) was 11. 0%-64. 3% and 0. 2%-61. 9%,respectively. There was obvious interaction effect among nitrogen,phosphorus and potassium fertilizers,the yield of maize was the highest at the level of medium nitrogen,medium phosphorus and medium potassium fertilization,and the fertilizer effect was in the order of N > P_2O_5> K_2O. The results of curve fitting showed that the recommended application rates of N,P2_O_5 and K_2O in MHQ plot were 373. 7,74. 8 and 79. 9 kg/ha,respectively; the recommended application rates of N,P_2O_5 and K_2O in HZY plot were 419. 7,75 and 75 kg/ha,respectively.
基金partially supported by the Forestry Technology Popularization Demonstration Project of the Central Government of China(2015-GDTK-07)
文摘Experiments were conducted to study the effects of density on growth and biomass partitioning of Leucaena leucocephala seedlings.Four plantations with densities of 10,000,20,000,40,000,and 80,000 seedlings ha^-1 were evaluated only from 15 to 25 months after planting.At 15 months,crown height and width decreased with increasing density.Seedling height/dbh ratios increased with increasing density.Biomass increased with greater density according to the yield–density effect equation,which was evident for all densities.With increasing age,biomass division to branches and leaves increased,whereas partitioning to roots decreased in the 10,000 and 20,000 seedlings ha-1 plantings.Partitioning to branches and leaves remained relatively steady,while partitioning to roots increased in the 40,000 and 80,000 seedlings ha^-1 plantings.Biomass division into stem and bark components remained relatively steady in all densities.Yield–density and organ yield–density curves shifted upward with increasing seedling age on a log–log graph throughout the experimental period.
文摘Soybean cultivar Bei 92-28 was tested in this experiment in 2000 to study the coupling effect of water and ferilizer on soybean yield.The results showed that the effect of irrigation varied among the levels of fertilizer application,and vice versa;pods per plant,seeds per pod.and 100-seed weight had positive correlations with soybean yield,but the degrees of correlations of different treatments were various;LAI and dry matter accumulation could be significantly increased when watered and applied fertilizer with different levels,but high fertilizer application treatment didn't obtain the highest yield;watering could increase the absolute absorption amount of N,P,K in seeds,but the accumulation rates were various.
基金Supported by Shanxi Provincial Key Research and Development Project in 2016(201603D3111005)National Project for Standardization of Chinese Materia Medica(ZYBZH-Y-JIN-34)Study and Application of Traditional Chinese Medicine Ecological Agriculture Based on Landscape Layout(2017YFC1700702)
文摘[Objectives] This study was conducted to further explore the yield increasing potential of Codonopsis pilosula, and to seek seedlings suitable for efficient production of C. pilosula. [Methods] The effects of C. pilosula seedlings of different sizes on root yield and commercial quality under different cultivation densities were studied. [Results] The fourth-grade seedlings had the least input, the highest yield of 6 948 kg/hm^2, the largest output-to-input ratio at 18.3, the highest root weight proportion of the second-grade product at 58.1%, and the lowest root weight proportion of the first-grade product at 17.6%. Considering the yield, quality and economic benefits comprehensively, the treatment of the fourth-grade seedlings(seedling diameter≤4 mm) is the best choice, and the suitable plant spacing is 8 cm×22 cm. [Conclusions] The study provided a reference basis for the cost saving and efficiency improvement of C. pilosula production.
基金supported by the Biogreen 21 R&D Program,Rural Development Administration,Republic of Korea(20100301-061-239-001-09-00)the National Agriculture Science Technology Achievement Transformation Fund of China(2011GB2B000006)
文摘Two genetic linkage maps, constructed by DH and RILs populations derived from the same parents, were carried out for the identification and comparison of QTLs controlling yield traits across different years in rice (Oryza sativa L.). A total of 194 SSR and STS markers were used in two maps, of which 114 markers were same. The distribution of Samgang allele was higher in RILs population than it in DH population. Comparing with DH population, RILs population has more lines with higher yield and wider phenotypic transgressive segression for yield traits. Although most of QTLs for the same trait were different in two populations across different years, 8 QTLs (including gwp 11.1, spp5.1, spp 10.1, spp 11.2, ssrl. 1, ssrl 1.1, tgw9.1 and tgwl 1.1) were detected over 2 yr. It is important to note that pppl0.1, sppl0.1 and tgw9.1 were identified in two populations, while sppl 0.1 and tgw9.1 were simultaneity observed across different years. Epistatic effects were more important than additive effects for PPP, SPP, yield in DH population and TGW, yield in R/Ls population. Epistatic effects of DH and RILs populations were different on the same genetic background in the present study, which illuminated the QE interaction played an important role on epistatic effect. Identification and comparison of QTLs for yield traits in DH and RILs populations should provide various and more precise information. The QTLs identified in present study would be valuable in marker-assisted selection program for improving rice yield.
基金Supported by Guangdong Science and Technology Program(2015A0202090112014A020208011+2 种基金2017A070701030)Key Supporting Farm Machine and Agronomic Technology Innovation Capacity Building Project for Improved Sugarcane Variety Breeding(Yue Nong Ji201506)Zhanjiang Science and Technology Project(2014A03020)
文摘In order to study the effect of 30% Tiange multifunctional pesticide-fertilizer on sugarcane pests and sugarcane yield,the field test was conducted with conventional compound fertilizer and 3% carbofuran fertilizer granules as control. The results showed that 30% Tiange multifunctional pesticide-fertilizer could effectively suppress some pests such as sugarcane borer,thrip,aphid and cockchafer. 90 d after pesticide-fertilizer application,the sugarcane withered heart rate was 1. 55% and 2. 55% in the two test points,respectively,significantly lower than the rate of 15. 40% and 19. 40% under control. Before harvest,the sugarcane borer damage rate in the two test points under pesticide-fertilizer treatment was 8. 70% and 9. 47%,respectively,significantly lower than the rate of 34. 50% and 33. 50% under control,and the sugarcane yield was 21. 16% and 22. 14% higher than under control,respectively. 30% Tiange multifunctional pesticide-fertilizer had nutritional and insecticidal effect,which could help to achieve sugarcane pesticide-fertilizer integration and save labor and costs.
文摘This work is concerned with the estimation from the outside of effective yield strength for the stage II consolidated material package of axisymmetric solid particles. Once an appropriate simple representative axisymmetric unit cell is chosen, the kinematical approach of the yield design homogenization method is used in order to obtain external estimates which has been found depending on the loading history (isostatic and closed die compactions) as well as on the relative density of the material powder. For comparison purpose, finite element simulations that describe the behavior of spherical elastic plastic particles uniformly distributed inside the material powder are carried out.
文摘According to the analysis of 654 soil samples collected from 45 counties in Zhejiang Provence, 73.7% of paddy field showed Si deficient. During 1991 and 1993, in Lishi, Longquang, Qingtian and Tonglu Counties, field experiments were conducted to test the effects of basal or additional Si-fertilizer on rice. Si-fertilizer was produced by Nanjing Inorganic Chemical Manufacture, containing 50% water solu
文摘Field experiments were conducted to determine the effect of composts prepared from different organic materials with rock phosphate (RP) on yield and P uptake of berseem and their residual effect on maize crop (cv. Azam) during 2011-2012. Composts prepared from RP fed farm yard manure (FYM), simple FYM, organic waste and city garbage were applied at the rate based on their P concentrations. Composts significantly (P ≤ 0.05) increased total dry matter weight of Berseem in first and second cut over control. Residual effect of the prepared composts was determined on yield and plant P uptake of maize in the same layout of Berseem. Maximum and significantly (P ≤ 0.05) higher maize grain yield, total dry matter yield and stover yield of 3161 kg·ha-1, 9633 kg·ha-1 and 6472 kg·ha-1, respectively were recorded by the residual effect of compost of organic waste with half dose of SSP. Thousand grains weight of 220 g was noted in the treatment of residual effect of compost of RP fed FYM with half dose of SSP. Post harvest soil N and P concentrations improved with composting. Significant (P ≤ 0.05) increases in N and P uptake by berseem and maize plants were observed with added composts. Results suggest that the use of composts prepared from different organic materials with RP is environmental friendly and has potential to improve crops yield and plants N and P uptakes for a prolonged time.
文摘A field experiment was conducted to examine the residual influence of biochar applied previously to an established experiment at the Agriculture University Research Farm, Peshawar on soil properties and yield of maize crop during summer 2016. The experiment was established in RCB design with split plot arrangements having cropping systems (CS) in main plots and biochar (BC) in sub-plots. Cropping systems were: 1) wheat-mung bean;2) wheat-maize;3) chickpea-maize;and 4) chickpea-mung bean. During the past three seasons, each cropping system received biochar at 0, 40, 60 and 80 t·haǃ along with recommended dose of NPK in each season. For this study, maize was planted after chickpea and wheat in summer 2016. The results showed that grain yield, cobs weight and total N uptake of maize was significantly greater for chickpea-maize than for wheat-maize cropping system. Soil organic C was also significantly higher in soil under chickpea-maize than under wheat-maize cropping system. However, other yield components such as stover yield, harvest index and N concentration in grain and stover of maize and soil properties such as pH, EC and mineral N were non-significantly affected by cropping systems. With respect to residual effect of biochar grain yield of maize and bulk density of soil were maximum for treatment receiving biochar at 40 t·haǃ whereas cobs weight soil pH and mineral N were highest receiving biochar at 60 t·haǃ. Moreover, N concentration in stover, N uptake and soil organic C were maximum for treatment receiving biochar at 80 t·haǃ. However, stover yield, harvest index, N concentration in grain, and soil EC were non-significantly affected by biochar treatments. However interactions between CS × BC were significant for yield and yield parameters of maize and for soil properties (bulk density mineral N), while non-significant for harvest index, soil organic C, pH and EC. It was concluded that chickpea-maize cropping system performed better in terms of improving yield and yield components of maize and in improving soil properties. Application of biochar to previous crops also improved yield and yield parameters of the following maize as well as soil properties. Thus we recommend that legumes must be involved in cropping system for sustainable and higher productivity and improved soil properties. However, further studies are suggested to find out suitable dose of biochar for sustainable and economic crop productivity and soil fertility.
文摘Salinity is the major limiting factor for forage productivity in southwestern coastal region of Bangladesh. Some introduced forage cultivars have been shown promising adaptability in saline conditions. The objective of this study was to assess the productivity and measure the agronomic characteristics of several introduced grass species with different created soil salinity levels. This study was conducted at the net house of Dr. Purnendu Gain Field Laboratory, Agrotechnology Discipline, and Khulna University during the period from December 2017 to February 2018. The experiment was laid out in a factorial randomized complete block design with seven replications. The experiment consisted of two factor viz. soil salinity levels (S<sub>1</sub> = 0.48, S<sub>2</sub> = 5.8, S<sub>3</sub> = 7.9, S<sub>4</sub> = 9.4, S<sub>5</sub> = 15 d<span style="white-space:nowrap;">·</span>Sm<sup><span style="white-space:nowrap;">−</span>1</sup>) and thirteen forage genotypes. Salinity levels and forage genotypes significantly (p < 0.05) influence all the growth parameters and biomass yield. The growth parameters and yield gradually decreased with the advance of soil salinity level. The tallest plant height (109.85 cm) was found in S<sub>1</sub> at 90 DAS while the shortest plant (24.53 cm) was obtained in S<sub>5</sub> at 90 DAS. Soil salinity had a significant difference (p < 0.001) on plant height at 90 DAS. The highest numbers of tillers (3.36) were found in S<sub>1</sub>, whereas the lowest (0.48) was in S<sub>5</sub> at 75 DAS. Soil salinity had a significant difference (p < 0.001) on Number of tillers at 75 DAS. The highest biomass wt. (29.14 g) was found in S<sub>1</sub>, while the lowest biomass wt. (3.52 g) was obtained in S<sub>5</sub> at 60 DAS. Soil salinity had a significant difference (p < 0.001) on biomass wt. at 60 DAS. The highest dry matter% (DM%) (21.24%) was found in S<sub>4</sub>, while the lowest DM (18.74%) was obtained in S<sub>1</sub> at 60 DAS. Soil salinity had a significant difference (p < 0.001) on dry matter% (DM%) wt. at 90 DAS. The tallest plant height (81.93 cm) was found in Pakchong, while the shortest plant (20.13 cm) was obtained in Endropogan at 60DAS. Soil salinity had a significant difference (p < 0.001) on plant height at 60 DAS. The highest numbers of tillers (3.07) were also found in Napier-3, whereas the lowest (0.80) was in H. Jaumbo at 75 DAS (S<sub>1</sub> + S<sub>2</sub> + S<sub>3</sub> + S<sub>4</sub> + S<sub>5</sub>). Soil salinity had a significant difference (p < 0.001) on Number of tillers at 75 DAS. The highest biomass wt. (38.60 g) was found in Pakchong, while the lowest biomass wt. (4.49 g) was obtained in Oats at 60 DAS. Soil salinity had a significant difference (p < 0.001) on biomass wt. at 60 DAS (S<sub>1</sub> + S<sub>2</sub> + S<sub>3</sub> + S<sub>4</sub> + S<sub>5</sub>). The highest (DM%) was found in Endropogan (24.68%), while the lowest DM (18.37%) was obtained Spelindida. Soil salinity had a significant difference (p < 0.001) on DM at 90 DAS. It can be concluded that Pakchong appears to be highly salt tolerant.
文摘A pot experiment was conducted to investigate the effect of coconut peat on growth and yield response of Ipomoea aquatica for Pirojpur soil series during the period of 24th May to 25th June, 2017. The experiment was laid to fit a completely randomized design (CRD) with five treatments [control (T0), 1000 kg coconut peat ha-1 (T1), 1500 kg coconut peat ha-1 (T2), 2000 kg coconut peat ha-1 (T3) and 2500 kg coconut peat ha-1 (T4)] each having three replications for this experiment. After plant harvesting, the laboratory investigation was carried out in the Soil, Water and Environment Discipline, Khulna University, Khulna, Bangladesh. Yield contributing characters like number of leaves, fresh weight and dry weight were significantly (P < 0.05) influenced by different treatments. By contrast root length and shoot length were insignificantly varied compared to control (T0) treatment but from the eye observation and analytical data confirm increasing trend for the application of coconut peat. Among the five treatments applied T4 treatment (2500 kg coconut peat ha-1) has shown highest response to plant growth due to nutrient availability of the soil. The sequence of response was in the order T4 > T3 > T2 > T1 > T0 and significantly (P 0).
文摘The ecological and physiological water require-ment of rice and rice yield was studied underthree irrigation patterns, which were A: moistirrigation, remains 70-90% of saturated soilwater content except 3-4 cm deep water layerin tillering stage in paddy; B: flood irrigation,remains 4-5 cm deep water layer except 80%relative water content in the late tillering stage