The root rot is a major disease affecting yield of Gentiana macrophyl a pal , reducing yield or even causing total crop failure. This research introduced the occurrence characteristics and various control techniques o...The root rot is a major disease affecting yield of Gentiana macrophyl a pal , reducing yield or even causing total crop failure. This research introduced the occurrence characteristics and various control techniques of root rot of Gentiana macrophyl a pal , in order to provide references for farmers.展开更多
It was hypothesized that wood chips can serve as a mulch to improve the growth of young trees by facilitating the development of their root systems, inhibiting weed germination, and suppressing weed growth. The presen...It was hypothesized that wood chips can serve as a mulch to improve the growth of young trees by facilitating the development of their root systems, inhibiting weed germination, and suppressing weed growth. The present study was carried out in Ghorogh Nursery, Golestan Northern Iran, in order to investigate the impact of wood chips applica- tion on root growth of oak (Quercus castaneifolia) seedlings and control of weed. A three centimeter wood chip layer was used on the soil surface as the mulch treatment with bare soil as the control. The number of new roots, the length of exciting roots and the density of weeds were meas- ured after 5 and 12 weeks. Results showed that wood chip application had significant positive effect on the length of excising roots after 5 and 12 weeks compared with control seedlings. Also, weeds were reduced to near zero levels in treated plot. Our findings suggested that wood chip layer on the soil surface in the nursery can conserve soil moisture and prevent nutrient leaching from the rooting zone as well as diminish weed growth which consequently lead to production of high quality seedling.展开更多
Single or mixed use ofAgaricus bisporus residue and microbial agent had better control effect on cucumber root-knot nematode disease in greenhouse. The results showed that the control effect of single use of A. b/spor...Single or mixed use ofAgaricus bisporus residue and microbial agent had better control effect on cucumber root-knot nematode disease in greenhouse. The results showed that the control effect of single use of A. b/sporus residue was 32.9% - 34.7%, and the yield increasing rate was 2.1% - 8.7% ; the control effect of mixed use ofA. b/sporus residue and microbial agent was 59. 1% - 63. 6%, and yield increasing rate was 2.6% - 3.5%. The experimental dose had no ad- verse effects on soil physical and chemical properties. The mixed use of A. b/sporus residue and microbial agent was one of the effective ways to control root-knot nematode disease.展开更多
Kiwifruit root rot is an important root disease of kiwifruit, which has occurred increasingly in recent years. The disease leads to the death of whole kiwifruit plant under severe condition, and has become an importan...Kiwifruit root rot is an important root disease of kiwifruit, which has occurred increasingly in recent years. The disease leads to the death of whole kiwifruit plant under severe condition, and has become an important disease restricting kiwi fruit industry development. The characteris-tics, occurrence, etiology and symptoms of kiwifruit root rot were introduced in the paper, and the prevention and control technology against the dis-ease were put forward from the aspects of agriculture, biology and chemistry.展开更多
为了解芽孢杆菌(Bacillus spp.)对作物根腐病防治效果及其影响因素,使用Meta分析方法对Web of Science和中国知网(CNKI)数据库检索筛选到的108篇文献479组有效数据,进行异质性检验、发表偏移检验和整合分析.结果表明,施用芽孢杆菌对作...为了解芽孢杆菌(Bacillus spp.)对作物根腐病防治效果及其影响因素,使用Meta分析方法对Web of Science和中国知网(CNKI)数据库检索筛选到的108篇文献479组有效数据,进行异质性检验、发表偏移检验和整合分析.结果表明,施用芽孢杆菌对作物根腐病有显著防效真实可靠(R=0.529,P<0.001,I^(2)=99.30%).纳入分析数据不存在发表偏移,但异质性大,需要开展分组分析.分组分析表明,菌种、制剂、有效活菌、施用方式及防效时长对防效影响显著(P≤0.001),其中制剂与施用方式的影响较突出(R=0.528);而作物类别、施用目的、次数和种植环境则对防效无显著影响(P>0.1).综上,建议种植前采用低浓度多粘类芽孢杆菌菌剂拌土施用1次,并于15 d后密切监测病害情况,及时采取后续措施.展开更多
USB接口被广泛地应用在计算机外设接口地设计中 ,尤其是嵌入式系统和穿戴计算机系统 .为了减小系统的体积 ,提高系统的集成度 ,可以利用 System On Chip技术将 USB主机控制器集成在微处理器中 ,构成片上系统 ,这就需要自行设计 U SB主...USB接口被广泛地应用在计算机外设接口地设计中 ,尤其是嵌入式系统和穿戴计算机系统 .为了减小系统的体积 ,提高系统的集成度 ,可以利用 System On Chip技术将 USB主机控制器集成在微处理器中 ,构成片上系统 ,这就需要自行设计 U SB主机控制器的核 (Core) .本文系统地剖析了 U SB主机控制器的原理和结构 ,并针对 OHCI从系统级上给出了一个典型的 U展开更多
The Activated Sludge Process(ASP) exhibits highly nonlinear properties. The design of an automatic control system that is robust against disturbance of inlet wastewater flow rate and has short process settling times i...The Activated Sludge Process(ASP) exhibits highly nonlinear properties. The design of an automatic control system that is robust against disturbance of inlet wastewater flow rate and has short process settling times is a challenging matter. The proposed control method is an I-P modi fied controller automatic control system with state variable feedback and control canonical form simulation diagram for the process. A more stable response is achieved with this type of modern control. Settling times of 0.48 days are achieved for the concentration of microorganisms,(reference value step increase of 50 mg·L-1) and 0.01 days for the concentration of oxygen(reference value step increase of 0.1 mg·L-1). Fluctuations of concentrations of oxygen and microorganisms after an inlet disturbance of5 × 103m3·d-1are small. Changes in the reference values of oxygen and microorganisms(increases by 10%, 20% and 30%) show satisfactory response of the system in all cases. Changes in the value of inlet wastewater flow rate disturbance(increases by 10%, 25%, 50% and 100%) are stabilized by the control system in short time. Maximum percent overshoot is also taken in consideration in all cases and the largest value is 25% which is acceptable. The proposed method with I-P controller is better for disturbance rejection and process settling times compared to the same method using PI controller. This method can substitute optimal control systems in ASP.展开更多
The flowability of a root canal sealer is clinically important because it improves the penetration of the sealer into the complex root canal system. The purpose of this study was to compare the flowabilities of four r...The flowability of a root canal sealer is clinically important because it improves the penetration of the sealer into the complex root canal system. The purpose of this study was to compare the flowabilities of four root canal sealers, measured using the simple press method (ISO 6876), and their viscosities, measured using a strain-controlled rheometer. A newly developed, calcium phosphate-based root canal sealer (Capseal) and three commercial root canal sealers (AH Plus, Sealapex and Pulp Canal Sealer EWT) were used in this study. The flowabilities of the four root canal sealers were measured using the simple press method (n= 5) and their viscosities were measured using a strain-controlled rheometer (n=5). The correlation between these two values was statistically analysed using Spearman's correlation test. The flow diameters and the viscosities of the root canal sealers were strongly negatively correlated (p= -0.8618). The viscosity of Pulp Canal Sealer EWT was the lowest and increased in the following order: AH Plus〈Sealapex〈Capseal (P〈0.05). All of the tested root canal sealers showed characteristic time- and temperature-dependent changes in their rheological properties. The viscosities measured using the strain-controlled rheometer were more precise than the flowabilities measured using the simple press method, suggesting that the rheometer can accurately measure the rheological properties of root canal sealers.展开更多
This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005...This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005 to study the influences of single basal application of 3 controlled-release fertilizers on the changes of soil available N, root development, senescence and lodging resistance at late growth stages. Results showed that at 30 days after fertilization, single basal application of controlled-release fertilizers coated with vegetal-substance (CRF1) and polymer materials (CRF3) increased soil available N to 12.0 and 147.9%, respectively, in comparison to split fertilization of rice-specific fertilizer (RSF1). Treatments of the two CRFs obviously benefited the development of root system, resulting in greater rice root weights with extensive distribution and higher root activity. In addition, the two CRF treatments, in comparison to RSF1, enhanced chlorophyll consents of the flag leaves to 9.5 and 15.5%, and soluble protein up to 89.7 and 108.0% respectively. Application of the two CRFs also made the base of rice stems strong and large, declined the proportion of shoot and root, increased root depth index. Though relatively low K rate, single basal application of the CRF3 coated with NH4MgPO4 could also promote the development of root system, enhance root activity and some physiological functions of flag leaves. Based on these results, it was concluded that major mechanisms for increasing rice yield by single basal application of the CRFs should be attributed to grater soil available N supply, superior development of root systems, better nutrient absorption capacity, slower senescence and enhancement of lodging resistance at late stages.展开更多
In this paper, an algorithm designed by the author is used to construct the general solution to difference equations with constant coefficients. It is worth noting that the algorithm does not require any information o...In this paper, an algorithm designed by the author is used to construct the general solution to difference equations with constant coefficients. It is worth noting that the algorithm does not require any information on the multiple roots of the characteristic equation. This means one does not need to reconfigure the algorithm when changing the multiplicity groups. It is for this reason that the algorithm is called “universal”. In the present study, we solve the task of finding a linear optimal control for linear stationary discrete one- and higher-dimensional systems with scalar control. Moreover, we give analytical expressions for the control that minimize the quadratic criterion and ensure the asymptotic stability of the closed system. The obtained optimal control depends only on the parameters of the initial system and the roots of the characteristic equation.展开更多
为中药材根腐病的生物防治提供有效的生防种质资源,本文从1万多株细菌中通过平板拮抗法筛选获得3株对镰刀菌抑菌活性较强的根际细菌LHJS2-2、LHQS2-5和YHQS2-7,对尖孢镰刀菌F.oxysporum295、腐皮镰刀菌F.solaniN18和轮枝镰刀菌F.vertici...为中药材根腐病的生物防治提供有效的生防种质资源,本文从1万多株细菌中通过平板拮抗法筛选获得3株对镰刀菌抑菌活性较强的根际细菌LHJS2-2、LHQS2-5和YHQS2-7,对尖孢镰刀菌F.oxysporum295、腐皮镰刀菌F.solaniN18和轮枝镰刀菌F.verticillium173的抑菌带为12~17mm,对串珠镰刀菌F.moniliforme N19的抑菌带是3~5 mm。经形态观察、生理生化试验及16S r DNA鉴定结果表明,菌株LHJS2-2为短小芽胞杆菌B.pumilus,菌株LHQS2-5为贝莱斯芽胞杆菌B.velezensis,菌株YHQS2-7为深褐芽胞杆菌B.atrophaeus。盆栽试验结果表明,菌株LHJS2-2、LHQS2-5和YHQS2-7对黄芪根腐病的预防效果分别是88.07%、85.66%和76.73%,显著促进黄芪、黄芩、银柴胡幼苗株高、根长、地上部生物量和地下部生物量。田间试验结果表明,菌株LHJS2-2、LHQS2-5和YHQS2-7对黄芪根腐病的防治效果分别为41.37%、40.13%和41.95%,对党参根腐病的田间预防效果分别达到87.06%、95.03%和87.06%。菌株LHJS2-2、LHQS2-5和YHQS2-7对中药材根腐病的生物防治具有重要的前景。展开更多
The control effects and application methods of Pleurotus ostreatus on the peanut root-knot nematode disease, Meloidogyne arenaria, were systematically studied in the greenhouse. Results of pot experiments showed that ...The control effects and application methods of Pleurotus ostreatus on the peanut root-knot nematode disease, Meloidogyne arenaria, were systematically studied in the greenhouse. Results of pot experiments showed that P. ostreatus could effectively reduce the 2nd-instar population density in the soil, and the larva reduced by 80% compared with the control. P. ostreatus could markedly lower the infecting number of the peanut root-knot nematodes, the nematode density inside the root knots declined by 40.00% -82.64%, and the peanut root knots also reduced by 86.96% - 94. 03%. The fungus could defer the initial infection of M. arenaria to the roots, the epidemic rate of the peanut root-knot nematode disease was significantly cut down, and the increase of root-knot changed from the way of Logistic curve in the control to the way of linear curve in the treatment. The final control effectiveness was about 80%. The results of pot trial also indicated that the control effectiveness is closely related to the application time and the amount of this fungus. The key factor affecting control effectiveness was the application time of P. ostreatus in the soil and the suitable time was 20 days before sowing.展开更多
文摘The root rot is a major disease affecting yield of Gentiana macrophyl a pal , reducing yield or even causing total crop failure. This research introduced the occurrence characteristics and various control techniques of root rot of Gentiana macrophyl a pal , in order to provide references for farmers.
文摘It was hypothesized that wood chips can serve as a mulch to improve the growth of young trees by facilitating the development of their root systems, inhibiting weed germination, and suppressing weed growth. The present study was carried out in Ghorogh Nursery, Golestan Northern Iran, in order to investigate the impact of wood chips applica- tion on root growth of oak (Quercus castaneifolia) seedlings and control of weed. A three centimeter wood chip layer was used on the soil surface as the mulch treatment with bare soil as the control. The number of new roots, the length of exciting roots and the density of weeds were meas- ured after 5 and 12 weeks. Results showed that wood chip application had significant positive effect on the length of excising roots after 5 and 12 weeks compared with control seedlings. Also, weeds were reduced to near zero levels in treated plot. Our findings suggested that wood chip layer on the soil surface in the nursery can conserve soil moisture and prevent nutrient leaching from the rooting zone as well as diminish weed growth which consequently lead to production of high quality seedling.
基金Supported by Edible Fungus Industry Innovation Team Projects of Shandong Agricultural Industry Research System(SDAIT-11-011-08)
文摘Single or mixed use ofAgaricus bisporus residue and microbial agent had better control effect on cucumber root-knot nematode disease in greenhouse. The results showed that the control effect of single use of A. b/sporus residue was 32.9% - 34.7%, and the yield increasing rate was 2.1% - 8.7% ; the control effect of mixed use ofA. b/sporus residue and microbial agent was 59. 1% - 63. 6%, and yield increasing rate was 2.6% - 3.5%. The experimental dose had no ad- verse effects on soil physical and chemical properties. The mixed use of A. b/sporus residue and microbial agent was one of the effective ways to control root-knot nematode disease.
基金Supported by Key Laboratory of Characteristic Fruit Resources Research and Utilization in Liupanshui(5202020170203)College Students Program of Liupanshui Normal University(LPSSY-DXS17054)
文摘Kiwifruit root rot is an important root disease of kiwifruit, which has occurred increasingly in recent years. The disease leads to the death of whole kiwifruit plant under severe condition, and has become an important disease restricting kiwi fruit industry development. The characteris-tics, occurrence, etiology and symptoms of kiwifruit root rot were introduced in the paper, and the prevention and control technology against the dis-ease were put forward from the aspects of agriculture, biology and chemistry.
文摘为了解芽孢杆菌(Bacillus spp.)对作物根腐病防治效果及其影响因素,使用Meta分析方法对Web of Science和中国知网(CNKI)数据库检索筛选到的108篇文献479组有效数据,进行异质性检验、发表偏移检验和整合分析.结果表明,施用芽孢杆菌对作物根腐病有显著防效真实可靠(R=0.529,P<0.001,I^(2)=99.30%).纳入分析数据不存在发表偏移,但异质性大,需要开展分组分析.分组分析表明,菌种、制剂、有效活菌、施用方式及防效时长对防效影响显著(P≤0.001),其中制剂与施用方式的影响较突出(R=0.528);而作物类别、施用目的、次数和种植环境则对防效无显著影响(P>0.1).综上,建议种植前采用低浓度多粘类芽孢杆菌菌剂拌土施用1次,并于15 d后密切监测病害情况,及时采取后续措施.
文摘USB接口被广泛地应用在计算机外设接口地设计中 ,尤其是嵌入式系统和穿戴计算机系统 .为了减小系统的体积 ,提高系统的集成度 ,可以利用 System On Chip技术将 USB主机控制器集成在微处理器中 ,构成片上系统 ,这就需要自行设计 U SB主机控制器的核 (Core) .本文系统地剖析了 U SB主机控制器的原理和结构 ,并针对 OHCI从系统级上给出了一个典型的 U
文摘The Activated Sludge Process(ASP) exhibits highly nonlinear properties. The design of an automatic control system that is robust against disturbance of inlet wastewater flow rate and has short process settling times is a challenging matter. The proposed control method is an I-P modi fied controller automatic control system with state variable feedback and control canonical form simulation diagram for the process. A more stable response is achieved with this type of modern control. Settling times of 0.48 days are achieved for the concentration of microorganisms,(reference value step increase of 50 mg·L-1) and 0.01 days for the concentration of oxygen(reference value step increase of 0.1 mg·L-1). Fluctuations of concentrations of oxygen and microorganisms after an inlet disturbance of5 × 103m3·d-1are small. Changes in the reference values of oxygen and microorganisms(increases by 10%, 20% and 30%) show satisfactory response of the system in all cases. Changes in the value of inlet wastewater flow rate disturbance(increases by 10%, 25%, 50% and 100%) are stabilized by the control system in short time. Maximum percent overshoot is also taken in consideration in all cases and the largest value is 25% which is acceptable. The proposed method with I-P controller is better for disturbance rejection and process settling times compared to the same method using PI controller. This method can substitute optimal control systems in ASP.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (2011-0014231)supported by the National Research Foundation of Korea funded by Ministry of Education, Science and Technology (2009-0086835)+1 种基金supported by a grant from the Kyung Hee University in 2013 (KHU-20131045)supported by Grant No. 04-2009-0032 from the SNUDH Research Fund
文摘The flowability of a root canal sealer is clinically important because it improves the penetration of the sealer into the complex root canal system. The purpose of this study was to compare the flowabilities of four root canal sealers, measured using the simple press method (ISO 6876), and their viscosities, measured using a strain-controlled rheometer. A newly developed, calcium phosphate-based root canal sealer (Capseal) and three commercial root canal sealers (AH Plus, Sealapex and Pulp Canal Sealer EWT) were used in this study. The flowabilities of the four root canal sealers were measured using the simple press method (n= 5) and their viscosities were measured using a strain-controlled rheometer (n=5). The correlation between these two values was statistically analysed using Spearman's correlation test. The flow diameters and the viscosities of the root canal sealers were strongly negatively correlated (p= -0.8618). The viscosity of Pulp Canal Sealer EWT was the lowest and increased in the following order: AH Plus〈Sealapex〈Capseal (P〈0.05). All of the tested root canal sealers showed characteristic time- and temperature-dependent changes in their rheological properties. The viscosities measured using the strain-controlled rheometer were more precise than the flowabilities measured using the simple press method, suggesting that the rheometer can accurately measure the rheological properties of root canal sealers.
文摘This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005 to study the influences of single basal application of 3 controlled-release fertilizers on the changes of soil available N, root development, senescence and lodging resistance at late growth stages. Results showed that at 30 days after fertilization, single basal application of controlled-release fertilizers coated with vegetal-substance (CRF1) and polymer materials (CRF3) increased soil available N to 12.0 and 147.9%, respectively, in comparison to split fertilization of rice-specific fertilizer (RSF1). Treatments of the two CRFs obviously benefited the development of root system, resulting in greater rice root weights with extensive distribution and higher root activity. In addition, the two CRF treatments, in comparison to RSF1, enhanced chlorophyll consents of the flag leaves to 9.5 and 15.5%, and soluble protein up to 89.7 and 108.0% respectively. Application of the two CRFs also made the base of rice stems strong and large, declined the proportion of shoot and root, increased root depth index. Though relatively low K rate, single basal application of the CRF3 coated with NH4MgPO4 could also promote the development of root system, enhance root activity and some physiological functions of flag leaves. Based on these results, it was concluded that major mechanisms for increasing rice yield by single basal application of the CRFs should be attributed to grater soil available N supply, superior development of root systems, better nutrient absorption capacity, slower senescence and enhancement of lodging resistance at late stages.
文摘In this paper, an algorithm designed by the author is used to construct the general solution to difference equations with constant coefficients. It is worth noting that the algorithm does not require any information on the multiple roots of the characteristic equation. This means one does not need to reconfigure the algorithm when changing the multiplicity groups. It is for this reason that the algorithm is called “universal”. In the present study, we solve the task of finding a linear optimal control for linear stationary discrete one- and higher-dimensional systems with scalar control. Moreover, we give analytical expressions for the control that minimize the quadratic criterion and ensure the asymptotic stability of the closed system. The obtained optimal control depends only on the parameters of the initial system and the roots of the characteristic equation.
文摘为中药材根腐病的生物防治提供有效的生防种质资源,本文从1万多株细菌中通过平板拮抗法筛选获得3株对镰刀菌抑菌活性较强的根际细菌LHJS2-2、LHQS2-5和YHQS2-7,对尖孢镰刀菌F.oxysporum295、腐皮镰刀菌F.solaniN18和轮枝镰刀菌F.verticillium173的抑菌带为12~17mm,对串珠镰刀菌F.moniliforme N19的抑菌带是3~5 mm。经形态观察、生理生化试验及16S r DNA鉴定结果表明,菌株LHJS2-2为短小芽胞杆菌B.pumilus,菌株LHQS2-5为贝莱斯芽胞杆菌B.velezensis,菌株YHQS2-7为深褐芽胞杆菌B.atrophaeus。盆栽试验结果表明,菌株LHJS2-2、LHQS2-5和YHQS2-7对黄芪根腐病的预防效果分别是88.07%、85.66%和76.73%,显著促进黄芪、黄芩、银柴胡幼苗株高、根长、地上部生物量和地下部生物量。田间试验结果表明,菌株LHJS2-2、LHQS2-5和YHQS2-7对黄芪根腐病的防治效果分别为41.37%、40.13%和41.95%,对党参根腐病的田间预防效果分别达到87.06%、95.03%和87.06%。菌株LHJS2-2、LHQS2-5和YHQS2-7对中药材根腐病的生物防治具有重要的前景。
文摘The control effects and application methods of Pleurotus ostreatus on the peanut root-knot nematode disease, Meloidogyne arenaria, were systematically studied in the greenhouse. Results of pot experiments showed that P. ostreatus could effectively reduce the 2nd-instar population density in the soil, and the larva reduced by 80% compared with the control. P. ostreatus could markedly lower the infecting number of the peanut root-knot nematodes, the nematode density inside the root knots declined by 40.00% -82.64%, and the peanut root knots also reduced by 86.96% - 94. 03%. The fungus could defer the initial infection of M. arenaria to the roots, the epidemic rate of the peanut root-knot nematode disease was significantly cut down, and the increase of root-knot changed from the way of Logistic curve in the control to the way of linear curve in the treatment. The final control effectiveness was about 80%. The results of pot trial also indicated that the control effectiveness is closely related to the application time and the amount of this fungus. The key factor affecting control effectiveness was the application time of P. ostreatus in the soil and the suitable time was 20 days before sowing.