To improve the efficiency of fetching and transplanting seedlings for the mechanization of strawberry planting,an integrated transplanting mechanism was designed with protruding,fetching and planting performance to ac...To improve the efficiency of fetching and transplanting seedlings for the mechanization of strawberry planting,an integrated transplanting mechanism was designed with protruding,fetching and planting performance to achieve rapid fetching and pushing bowl movements.According to the working principle of the slewing mechanism,a kinematics model and the optimization goal were established,respectively.Based on visual auxiliary analysis software,optimal parameters were obtained.A three-dimensional model was established to obtain a simulation trajectory by means of a virtual simulation design analysis.Three-dimensional printing technology was used to manufacture the test prototype,and the actual working trajectories of the test prototype were extracted using high-speed photography technology,which verified the consistency of the actual trajectory with the theoretical and simulated trajectories.A prototype transplanting experiment was performed with the success rate of seedling extraction of 91.2%and excellent planting rate of 82.8%,which met the requirements for integrated strawberry harvesting,planting and transplanting.The experimental results verified the correctness and feasibility of the design of integrated transplanting mechanism.展开更多
Studies were initiated for two consecutive years to find out the effect of time of transplanting and seedlings hill?1 on the productivity of rice in Dera Ismail Khan district of North West Frontier Province (NWFP), Pa...Studies were initiated for two consecutive years to find out the effect of time of transplanting and seedlings hill?1 on the productivity of rice in Dera Ismail Khan district of North West Frontier Province (NWFP), Pakistan. The experiment was laid out in a randomized complete block design with split plot arrangements. Main plots consisted of four transplanting dates viz. 20th and 27th of June and 4th and 11th of July while sub-plots contained 1, 2, 3 or 4 seedlings hill?1. Among transplanting dates, June 20th planted crop gave highest paddy yield and net return with 1 seedling hill–1. It explains that the use of more seedlings hill?1 not only adds to cost but is also a mere wastage of natural resources. Based on research findings, we conclude that the use of 1 seedling hill?1 is most appropriate for timely sowing otherwise 4 seedlings hill–1 should be used to compensate for the yield gap in late transplanted rice.展开更多
This study was conducted to determine whether,and if so how,the grain yield and nitrogen(N) requirements of hybrid rice transplanted as single seedlings are affected by no-tillage(NT) practices.A fixed field experimen...This study was conducted to determine whether,and if so how,the grain yield and nitrogen(N) requirements of hybrid rice transplanted as single seedlings are affected by no-tillage(NT) practices.A fixed field experiment was done at the Experimental Farm of Hunan Agricultural University in Changsha,Hunan Province,China,from 2004 to 2014.Grain yield and yield attributes(panicle number per m2,spikelet number per panicle,spikelet filling percentage,grain weight,total biomass,and harvest index) were evaluated as well as the N-use characteristics(total N uptake,internal N-use efficiency,and N requirements) of hybrid rice transplanted as single seedlings comparing NT with conventional tillage(CT).A significant finding was that there were no significant differences in grain yield,yield attributes,and N-use characteristics between CT and NT.Averaged across the 11 years,grain yield and N requirements were 9.51 t ha^(-1) and 20.2 kg t^(-1) under CT and 9.33 t ha^(-1) and 20.0 kg t^(-1) under NT,respectively.There were significant yearly variations in grain yield,yield attributes,and N-use characteristics observed under both CT and NT.The yearly variation in grain yield was related to simultaneous changes in spikelet number per panicle,grain weight,total biomass,and harvest index.Also,it was found that grain yield was positively correlated with internal N-use efficiency but negatively correlated with N requirements.It is concluded that grain yield and N requirements in hybrid rice when transplanted as single seedlings are not affected adversely by NT.The results of this study suggest that(1) compatible relationships among yield attributes can be established in hybrid rice that is transplanted as single seedlings,and(2) higher grain yield and higher N-use efficiency can be concurrently achieved in hybrid rice transplanted as single seedlings.展开更多
To improve the yield of Diwangcai and explore its best cultivation way,direct seeding and seedling transplanting of Diwangcai were contrasted. The results showed that cumulative annual yield of Diwangcai by seedling t...To improve the yield of Diwangcai and explore its best cultivation way,direct seeding and seedling transplanting of Diwangcai were contrasted. The results showed that cumulative annual yield of Diwangcai by seedling transplanting was 16% higher than that by direct seeding.展开更多
With the development of China's social economy,transfer of rural labors,and rise of labor costs,the rice production technologies are changing from manual operation to mechanical operation.The core of mechanical ri...With the development of China's social economy,transfer of rural labors,and rise of labor costs,the rice production technologies are changing from manual operation to mechanical operation.The core of mechanical rice production is mechanical planting,while the key to mechanical planting is the seedling raising.On the basis of analyzing and studying the problems and experience of traditional mechanical transplanting of rice,a new overlapped tray seedling raising model was introduced.Main features of this model: substrate seedling raising and overlapped seedling tray.The seedling trays for seeding line are overlapped,and the overlapped trays are moved into the seedling room with controlled temperature and humidity.The temperature of the seedling room is controlled at 30-32℃,and the humidity of the seedling room is controlled at above 90%.After about 48 h,when the seedling height reaches 0.5 cm,move the seedling trays to the nursery.This model consists of one seeding center( seedling raising center) and N nurseries,to realize 1 + N seedling raising for mechanical transplanting of rice.One seeding center can provide seedlings for several hundred to several thousand hectares of mechanical transplanting of rice,and provide a new model for social services.This model could improve the quality of seedlings,increase the seedling survival rate by about 20%,reduce the seedling raising costs by 15%-20%,reduce the seedling raising risks,and greatly increase the utilization rate of the site and equipment of seedling raising center.展开更多
This paper studies the factors that affect the safe full heading of machine-transplanted rice seedlings in the temperate and cool ricegrowing areas,and explores the influence of machine-transplanted rice seedling vari...This paper studies the factors that affect the safe full heading of machine-transplanted rice seedlings in the temperate and cool ricegrowing areas,and explores the influence of machine-transplanted rice seedling varieties,seedling age,nitrogen fertilizer application rate and management on the safe full heading of machine-transplanted rice seedlings. Results show that for the mechanized production in the temperate and cool rice-growing areas,we should select the mid-early maturity cold-resistant varieties with growth period of not exceeding 180 d,control the seedling age to be 30- 35 d and total amount of pure nitrogen to be not more than 300 kg / ha,and moderately reduce the nitrogen fertilizer postponing ratio. Under this condition,we can achieve safe full heading of machine-transplanted rice seedlings and ensure the yield.展开更多
[Objectives]The paper was to investigate the relationship between the well-cellar early transplanting of robust seedlings and the prevalence of diseases in the Shiyan tobacco-growing area.[Methods]The relationship bet...[Objectives]The paper was to investigate the relationship between the well-cellar early transplanting of robust seedlings and the prevalence of diseases in the Shiyan tobacco-growing area.[Methods]The relationship between disease occurrence and meteorological factors during the field growth period was examined by analyzing the prevalence of flue-cured tobacco virus diseases,brown spot,and total disease in the Shiyan tobacco-growing area before(2013-2017)and after(2018-2022)the well-cellar early transplanting of robust tobacco seedlings.[Results]The implementation of a well-cellar early transplanting technique of robust seedlings resulted in a reduction in the average incidence of tobacco virus disease,brown spot,and total disease by 0.83%,8.85%,and 7.91%,respectively,in comparison to the incidence observed prior to early transplanting.These findings suggest that early transplanting can significantly reduce the incidence of flue-cured tobacco diseases.Prior to the well-cellar early transplanting of robust tobacco seedlings,there was a significant(including highly significant)positive correlation between the incidence of brown spot and total disease and precipitation in August and September.The incidence of brown spot and total disease in tobacco plants was found to be significantly positively correlated with May precipitation and significantly negatively correlated with May sunshine hours following the well-cellar early transplanting of robust seedlings.The advancement of the transplanting period by 20 d resulted in a reduction in the growing period of tobacco plants in the field under autumn rains(late August to November)in western China.This effectively circumvented the suitable conditions for disease occurrence and can reduce the incidence of disease.[Conclusions]This study offers a framework for enhancing the quality and efficiency of flue-cured tobacco production in the northwest tobacco-growing area of Hubei.展开更多
This study was conducted to investigate the effects of soilless substrates of hydroponically grown long-mat seedlings (HLMS) on seedling quality and field growth characteristics of transplanted super japonica rice. ...This study was conducted to investigate the effects of soilless substrates of hydroponically grown long-mat seedlings (HLMS) on seedling quality and field growth characteristics of transplanted super japonica rice. A widely grown conventional super japonica rice cultivar (Wuyunjing 23) was selected as the test material. The effect of HLMS on seedling quality, mechanical transplantation quality, field growth characteristics, yield, and benefit-cost ratio were compared with seedlings grown in organic substrates and traditional nutritive soil, whJch was selected as the control. Root number, root twJstJng power and root activity of seedlings cultivated by HLMS were decreased compared to that of the organic substrates andcontrol. However, seedling root length as well as aboveground growth were increased compared to the organic substrates and control seed- lings. In the HLMS, the content of gibberellin acid (GA3) decreased while abscisic acid (ABA) content increased compared to that of the organic substrates and control seedlings. During the early stages after transplanting, the re-greening of HLMS was delayed compared to that of the organic substrates and control seedlings. Nevertheless, there were no significant differences in tiller dynamics and crop yield among the HLMS, organic substrates and control treatments. The effects of HLMS on seedling production were similar to those of the organic substrates and traditional nutritive soil in the present study, suggesting that HLMS have the potential to replace traditional nutritive soil in seedling production without decreasing crop yield. Finally, it is important to reduce organic substrates and topsoil dependence during rice seedling production and worthwhile to consider HLMS popularization and its application on a larger scale.展开更多
Aiming at the lack of suitable machines for sweet potato seedling transplanting in China,and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling,a new sweet potato seed...Aiming at the lack of suitable machines for sweet potato seedling transplanting in China,and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling,a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical gear.The working principle of the transplanting mechanism was analyzed,and the kinematics modeling and analysis of the mechanism were carried out.The study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting mechanism.The parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting arm.Based on the optimized parameters,the structure of the transplanting mechanism was designed,and a virtual prototype of the mechanism was created,whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the mechanism.The high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism’s kinematic characteristics and transplanting performance.The test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory,meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling;And when the rotary speed of the mechanism are 20 r/min and 30 r/min,the average success ratios of sweet potato seedlings transplanting are 90%and 82%,respectively,which prove the application feasibility of the mechanism in the practical machines.展开更多
This study was conducted to identify the factors associated with high grain yield in single seedling machine-transplanted hybrid rice under dense planting conditions. Field experiments were done in Yong'an Town, Huna...This study was conducted to identify the factors associated with high grain yield in single seedling machine-transplanted hybrid rice under dense planting conditions. Field experiments were done in Yong'an Town, Hunan Province, China in 2015 and 2016. Two hybrid rice cultivars were grown under single seedling machine transplanting (SMT) and conventional machine transplanting (CMT) at a high planting density in each year. Grain yield and yield attributes were compared between SMT and CMT. Averaged across cultivars and years, grain yield was 12% higher under SMT than under CMT. Plant height, basal stem width, and shoot and root dry weights were higher in seedlings for SMT than those for CMT. SMT had less maximum tiller number per m2 and consequently less panicle number per m2 than did CMT. Branch number per panicle, especially the secondary branch number per panicle, and spikelet number per cm of panicle length were more under SMT than under CMT, which resulted in more spikelet number per panicle under SMT than under CMT. SMT had higher or equal spikelet filling percentage than did CMT. The difference in grain weight between SMT and CMT was relatively small and inconsistent cross years. SMT had higher or equal total biomass and harvest index than did CMT. Dry weight per stem under SMT was heavier than that under CMT. Larger leaf area per stem was partly responsible for the heavier dry weight per stem under SMT than under CMT. Our study suggests that improvement in seedling quality, panicle size, and dry weight per stem are critical to the high grain yield in single seedling machine-transplanted hybrid rice under dense planting conditions.展开更多
Global warming and consumer demand for medicinal plants present an opportunity to introduce ginger growth to the US Delmarva Peninsula. High tunnel and field studies were conducted to assess the development of organic...Global warming and consumer demand for medicinal plants present an opportunity to introduce ginger growth to the US Delmarva Peninsula. High tunnel and field studies were conducted to assess the development of organic ginger (<i><span style="font-family:Verdana;">Zingiber</span></i> <i><span style="font-family:Verdana;">officinalis</span></i><span style="font-family:Verdana;">, Rosc) seedling transplants in mycorrhiza-amended</span><span style="font-family:Verdana;"> soil. Transplant types were tissue culture derived with less than three tillers (TCS1), three or more tillers (TCS2), and nontissue culture derived (NTCS1). Transplants were grown with or without mycorrhiza (2.8 g per plant) in a split plot design with soil amendments as main plot and transplant type as subplot. Data were collected for air temperatures, plant height, tiller number, leaf chlorophyll index (LCI), rhizome fresh weight, plant biomass, rhizome nutrients, and levels of As and Pb. TCS2 transplants produced significantly higher, or trended to higher rhizome yield than transplants with less than three tillers, except for year two field study. The maximum rhizome fresh weight per plant was 648.3 g for TCS2 in high tunnel in year one. Generally, TCS2 had most tillers throughout the growing season ranging from 6.9 to 25.7 tillers per plant over three studies. Mycorrhiza had no effect on ginger height, tiller number, LCI or rhizome yield. Sustained high temperatures above 37°C, plus high light in the field caused dieback and stunted shoot growth in year two. There were no consistent effects of mycorrhiza or transplant type on rhizome nutrient content. Content of total Pb, As and other elements were at safe threshold levels for rhizome consumption. These results suggest that gingers grown from TCS2 transplants with at least three tillers yielded more rhizome than those grown from S1 transplants with fewer tillers. Introduction of ginger to a short season region such as the Delmarva may require consideration of environmental condition such as high temperature and light to which seedling transplants may be exposed in summer.</span>展开更多
In order to explore a new mulch-free maize planting mode and the best seedling age for maize transplantation in Shanxi early mature area,a field experiment was carried out using completely randomized block design. Tak...In order to explore a new mulch-free maize planting mode and the best seedling age for maize transplantation in Shanxi early mature area,a field experiment was carried out using completely randomized block design. Taking mulch based direct sowing as the control group,effects of transplantation in different seedling age on maize growing process,plant height,yield and composition factors of maize were analyzed.Results indicate that growing process of maize seedlings transplanted in different seedling age is slightly slower than the control group. Transplantation has the effect of reducing plant height. Although the yield of transplanted maize in different seedling age is lower than the control group. Besides,with the growth of seedling age of transplantation,the gap is widening. However,it is expected to realize mulch-free maize planting by transplantation in Shanxi early mature area. The yield of maize transplanted in two-leaf seedling age is not significantly different from the control group,and the yield is only 9% lower than the mulch-based direct sowing( CK). In conclusion,two-leaf period is the best seedling transplantation age for maize in Shanxi early mature area in this experiment condition.展开更多
“Rice transplanter” has brought a radical change in the method of rice seedlings transplanting in Bangladesh. The machine is gaining popularity with the increase of labor crisis during the peak period of transplanti...“Rice transplanter” has brought a radical change in the method of rice seedlings transplanting in Bangladesh. The machine is gaining popularity with the increase of labor crisis during the peak period of transplanting, reduction time of in-between crops, rapid urbanization and industrialization, and changing socio-economic status of the farmers. Alternatively, the traditional way of rice transplanting is labor-intensive and involves high drudgery. Mechanical rice transplanter is cost-effective and operation-friendly. It is suitable to plant young seedlings maintaining plant to plant and line to line distance which plays an important role in increasing yield. Moreover, it is easy to take care of the crops planted in rows. It helps in maintaining soil physical properties and is considered to be better from a crop management and productivity point of view. In malignancy of having an edge over the traditional broadcasting, the adoption rate of mechanical transplanters is low due to high primary investment, lack of knowledge in growing mat type nursery, lack of repair and maintenance facility to the end-users, and unavailability of spare parts. Imparting these, available supply, entrepreneurship development, and encouraging custom hire services may be some of the practical results for adding the rice area under mechanical transplanting. This review summarizes the problems and prospects associated with seedling rice transplanting, technological gaps in the adoption of mechanical transplanters in a sustainable manner, and future ways to make transplanters more user-friendly and cost-effective.展开更多
Side insertion horizontal transplanting sweet potato seedlings on mulch film is one kind of new planter pattern,which keeps the soil warm and moist restraining the infestation of pests and weeds,realizing dense transp...Side insertion horizontal transplanting sweet potato seedlings on mulch film is one kind of new planter pattern,which keeps the soil warm and moist restraining the infestation of pests and weeds,realizing dense transplanting and ensuring uniformity of sweet potato sizes.Therefore,a side insertion horizontal transplanting device for sweet potato seedlings on mulch film was designed,including the details and parameters of the reciprocating mechanism and the seedling clamping mechanism.Both the two mechanisms and the whole device were simulated and the test bench was built for field experiments to detect if this device can meet the agronomic requirements.The simulation results show that the designed device is in accordance with the agronomic requirements of horizontal transplanting,transplanting depth and transplanting length,and is potential for achieving rational close planting.The lateral length of the designed transplanting device is extended at about 90 mm compared with previous machine,which will promote the number of soil nodules of sweet potato seedlings and the growth of production enormously.The horizontal velocity of the transplanting claw is−17 mm/s when picking the seedling,the horizontal velocity of the transplanting claw 645 mm/s and the vertical velocity 83 mm/s when releasing the seedling.These data could ensure the accuracy requirements of horizontal transplanting trajectory.The field experiment results show the expulsion rate of sweet potato seedlings at 1.38%,the qualified rate of transplanting length and depth at 94.17%and 95.11%respectively,the average length and width of the mulch film breaking hole at 44.67 mm and 43.00 mm in several.The postures of the actual transplanted seedlings are consistent with the simulation results,meeting the requirements of horizontal transplanting with less damage to the mulch film.The designed transplanting device lays a foundation for the development of sweet potato seedlings side transplanting machine.展开更多
基金Supported by the National Natural Science Foundation of China Youth Fund Project(52005221)"the 13th Five-Year"National Key Research and Development Program:High-speed Planting Technology and Equipment Research and Development(2017YFD0700800)。
文摘To improve the efficiency of fetching and transplanting seedlings for the mechanization of strawberry planting,an integrated transplanting mechanism was designed with protruding,fetching and planting performance to achieve rapid fetching and pushing bowl movements.According to the working principle of the slewing mechanism,a kinematics model and the optimization goal were established,respectively.Based on visual auxiliary analysis software,optimal parameters were obtained.A three-dimensional model was established to obtain a simulation trajectory by means of a virtual simulation design analysis.Three-dimensional printing technology was used to manufacture the test prototype,and the actual working trajectories of the test prototype were extracted using high-speed photography technology,which verified the consistency of the actual trajectory with the theoretical and simulated trajectories.A prototype transplanting experiment was performed with the success rate of seedling extraction of 91.2%and excellent planting rate of 82.8%,which met the requirements for integrated strawberry harvesting,planting and transplanting.The experimental results verified the correctness and feasibility of the design of integrated transplanting mechanism.
文摘Studies were initiated for two consecutive years to find out the effect of time of transplanting and seedlings hill?1 on the productivity of rice in Dera Ismail Khan district of North West Frontier Province (NWFP), Pakistan. The experiment was laid out in a randomized complete block design with split plot arrangements. Main plots consisted of four transplanting dates viz. 20th and 27th of June and 4th and 11th of July while sub-plots contained 1, 2, 3 or 4 seedlings hill?1. Among transplanting dates, June 20th planted crop gave highest paddy yield and net return with 1 seedling hill–1. It explains that the use of more seedlings hill?1 not only adds to cost but is also a mere wastage of natural resources. Based on research findings, we conclude that the use of 1 seedling hill?1 is most appropriate for timely sowing otherwise 4 seedlings hill–1 should be used to compensate for the yield gap in late transplanted rice.
基金supported by the National Key R&D Program of China (2017YFD0301503)the National Natural Science Foundation of China (31301267)the earmarked fund for China Agriculture Research System (CARS-01)
文摘This study was conducted to determine whether,and if so how,the grain yield and nitrogen(N) requirements of hybrid rice transplanted as single seedlings are affected by no-tillage(NT) practices.A fixed field experiment was done at the Experimental Farm of Hunan Agricultural University in Changsha,Hunan Province,China,from 2004 to 2014.Grain yield and yield attributes(panicle number per m2,spikelet number per panicle,spikelet filling percentage,grain weight,total biomass,and harvest index) were evaluated as well as the N-use characteristics(total N uptake,internal N-use efficiency,and N requirements) of hybrid rice transplanted as single seedlings comparing NT with conventional tillage(CT).A significant finding was that there were no significant differences in grain yield,yield attributes,and N-use characteristics between CT and NT.Averaged across the 11 years,grain yield and N requirements were 9.51 t ha^(-1) and 20.2 kg t^(-1) under CT and 9.33 t ha^(-1) and 20.0 kg t^(-1) under NT,respectively.There were significant yearly variations in grain yield,yield attributes,and N-use characteristics observed under both CT and NT.The yearly variation in grain yield was related to simultaneous changes in spikelet number per panicle,grain weight,total biomass,and harvest index.Also,it was found that grain yield was positively correlated with internal N-use efficiency but negatively correlated with N requirements.It is concluded that grain yield and N requirements in hybrid rice when transplanted as single seedlings are not affected adversely by NT.The results of this study suggest that(1) compatible relationships among yield attributes can be established in hybrid rice that is transplanted as single seedlings,and(2) higher grain yield and higher N-use efficiency can be concurrently achieved in hybrid rice transplanted as single seedlings.
基金Supported by Dazhou Bast Comprehensive Test Station Program of National Bast Fiber Industry Technical System(CARS-16S17)
文摘To improve the yield of Diwangcai and explore its best cultivation way,direct seeding and seedling transplanting of Diwangcai were contrasted. The results showed that cumulative annual yield of Diwangcai by seedling transplanting was 16% higher than that by direct seeding.
文摘With the development of China's social economy,transfer of rural labors,and rise of labor costs,the rice production technologies are changing from manual operation to mechanical operation.The core of mechanical rice production is mechanical planting,while the key to mechanical planting is the seedling raising.On the basis of analyzing and studying the problems and experience of traditional mechanical transplanting of rice,a new overlapped tray seedling raising model was introduced.Main features of this model: substrate seedling raising and overlapped seedling tray.The seedling trays for seeding line are overlapped,and the overlapped trays are moved into the seedling room with controlled temperature and humidity.The temperature of the seedling room is controlled at 30-32℃,and the humidity of the seedling room is controlled at above 90%.After about 48 h,when the seedling height reaches 0.5 cm,move the seedling trays to the nursery.This model consists of one seeding center( seedling raising center) and N nurseries,to realize 1 + N seedling raising for mechanical transplanting of rice.One seeding center can provide seedlings for several hundred to several thousand hectares of mechanical transplanting of rice,and provide a new model for social services.This model could improve the quality of seedlings,increase the seedling survival rate by about 20%,reduce the seedling raising costs by 15%-20%,reduce the seedling raising risks,and greatly increase the utilization rate of the site and equipment of seedling raising center.
文摘This paper studies the factors that affect the safe full heading of machine-transplanted rice seedlings in the temperate and cool ricegrowing areas,and explores the influence of machine-transplanted rice seedling varieties,seedling age,nitrogen fertilizer application rate and management on the safe full heading of machine-transplanted rice seedlings. Results show that for the mechanized production in the temperate and cool rice-growing areas,we should select the mid-early maturity cold-resistant varieties with growth period of not exceeding 180 d,control the seedling age to be 30- 35 d and total amount of pure nitrogen to be not more than 300 kg / ha,and moderately reduce the nitrogen fertilizer postponing ratio. Under this condition,we can achieve safe full heading of machine-transplanted rice seedlings and ensure the yield.
基金Supported by Research Program on Prevention and Control Technology of Tobacco Potato Virus Y Disease(SYK2023-06).
文摘[Objectives]The paper was to investigate the relationship between the well-cellar early transplanting of robust seedlings and the prevalence of diseases in the Shiyan tobacco-growing area.[Methods]The relationship between disease occurrence and meteorological factors during the field growth period was examined by analyzing the prevalence of flue-cured tobacco virus diseases,brown spot,and total disease in the Shiyan tobacco-growing area before(2013-2017)and after(2018-2022)the well-cellar early transplanting of robust tobacco seedlings.[Results]The implementation of a well-cellar early transplanting technique of robust seedlings resulted in a reduction in the average incidence of tobacco virus disease,brown spot,and total disease by 0.83%,8.85%,and 7.91%,respectively,in comparison to the incidence observed prior to early transplanting.These findings suggest that early transplanting can significantly reduce the incidence of flue-cured tobacco diseases.Prior to the well-cellar early transplanting of robust tobacco seedlings,there was a significant(including highly significant)positive correlation between the incidence of brown spot and total disease and precipitation in August and September.The incidence of brown spot and total disease in tobacco plants was found to be significantly positively correlated with May precipitation and significantly negatively correlated with May sunshine hours following the well-cellar early transplanting of robust seedlings.The advancement of the transplanting period by 20 d resulted in a reduction in the growing period of tobacco plants in the field under autumn rains(late August to November)in western China.This effectively circumvented the suitable conditions for disease occurrence and can reduce the incidence of disease.[Conclusions]This study offers a framework for enhancing the quality and efficiency of flue-cured tobacco production in the northwest tobacco-growing area of Hubei.
基金provided by the National Key Technologies R&D Program of China during the 12th Five-Year Plan period(2016YFD0300505 and 2015BAD01B03)the Public Welfare and Industry,Ministry of Agriculture,China(201403039 and 201303102)the Fundamental Research Funds for the Central Universities,China(KYTZ201402)
文摘This study was conducted to investigate the effects of soilless substrates of hydroponically grown long-mat seedlings (HLMS) on seedling quality and field growth characteristics of transplanted super japonica rice. A widely grown conventional super japonica rice cultivar (Wuyunjing 23) was selected as the test material. The effect of HLMS on seedling quality, mechanical transplantation quality, field growth characteristics, yield, and benefit-cost ratio were compared with seedlings grown in organic substrates and traditional nutritive soil, whJch was selected as the control. Root number, root twJstJng power and root activity of seedlings cultivated by HLMS were decreased compared to that of the organic substrates andcontrol. However, seedling root length as well as aboveground growth were increased compared to the organic substrates and control seed- lings. In the HLMS, the content of gibberellin acid (GA3) decreased while abscisic acid (ABA) content increased compared to that of the organic substrates and control seedlings. During the early stages after transplanting, the re-greening of HLMS was delayed compared to that of the organic substrates and control seedlings. Nevertheless, there were no significant differences in tiller dynamics and crop yield among the HLMS, organic substrates and control treatments. The effects of HLMS on seedling production were similar to those of the organic substrates and traditional nutritive soil in the present study, suggesting that HLMS have the potential to replace traditional nutritive soil in seedling production without decreasing crop yield. Finally, it is important to reduce organic substrates and topsoil dependence during rice seedling production and worthwhile to consider HLMS popularization and its application on a larger scale.
基金financially supported by the Zhejiang Provincial Natural Science Foundation of China(Grant No.LD24E05007)the National Natural Science Foundation of China(Grant No.32201676,32171899).
文摘Aiming at the lack of suitable machines for sweet potato seedling transplanting in China,and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling,a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical gear.The working principle of the transplanting mechanism was analyzed,and the kinematics modeling and analysis of the mechanism were carried out.The study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting mechanism.The parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting arm.Based on the optimized parameters,the structure of the transplanting mechanism was designed,and a virtual prototype of the mechanism was created,whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the mechanism.The high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism’s kinematic characteristics and transplanting performance.The test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory,meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling;And when the rotary speed of the mechanism are 20 r/min and 30 r/min,the average success ratios of sweet potato seedlings transplanting are 90%and 82%,respectively,which prove the application feasibility of the mechanism in the practical machines.
基金supported by the National Key R&D Program of China (2017YFD0301503)the earmarked fund for China Agriculture Research System (CARS-01)
文摘This study was conducted to identify the factors associated with high grain yield in single seedling machine-transplanted hybrid rice under dense planting conditions. Field experiments were done in Yong'an Town, Hunan Province, China in 2015 and 2016. Two hybrid rice cultivars were grown under single seedling machine transplanting (SMT) and conventional machine transplanting (CMT) at a high planting density in each year. Grain yield and yield attributes were compared between SMT and CMT. Averaged across cultivars and years, grain yield was 12% higher under SMT than under CMT. Plant height, basal stem width, and shoot and root dry weights were higher in seedlings for SMT than those for CMT. SMT had less maximum tiller number per m2 and consequently less panicle number per m2 than did CMT. Branch number per panicle, especially the secondary branch number per panicle, and spikelet number per cm of panicle length were more under SMT than under CMT, which resulted in more spikelet number per panicle under SMT than under CMT. SMT had higher or equal spikelet filling percentage than did CMT. The difference in grain weight between SMT and CMT was relatively small and inconsistent cross years. SMT had higher or equal total biomass and harvest index than did CMT. Dry weight per stem under SMT was heavier than that under CMT. Larger leaf area per stem was partly responsible for the heavier dry weight per stem under SMT than under CMT. Our study suggests that improvement in seedling quality, panicle size, and dry weight per stem are critical to the high grain yield in single seedling machine-transplanted hybrid rice under dense planting conditions.
文摘Global warming and consumer demand for medicinal plants present an opportunity to introduce ginger growth to the US Delmarva Peninsula. High tunnel and field studies were conducted to assess the development of organic ginger (<i><span style="font-family:Verdana;">Zingiber</span></i> <i><span style="font-family:Verdana;">officinalis</span></i><span style="font-family:Verdana;">, Rosc) seedling transplants in mycorrhiza-amended</span><span style="font-family:Verdana;"> soil. Transplant types were tissue culture derived with less than three tillers (TCS1), three or more tillers (TCS2), and nontissue culture derived (NTCS1). Transplants were grown with or without mycorrhiza (2.8 g per plant) in a split plot design with soil amendments as main plot and transplant type as subplot. Data were collected for air temperatures, plant height, tiller number, leaf chlorophyll index (LCI), rhizome fresh weight, plant biomass, rhizome nutrients, and levels of As and Pb. TCS2 transplants produced significantly higher, or trended to higher rhizome yield than transplants with less than three tillers, except for year two field study. The maximum rhizome fresh weight per plant was 648.3 g for TCS2 in high tunnel in year one. Generally, TCS2 had most tillers throughout the growing season ranging from 6.9 to 25.7 tillers per plant over three studies. Mycorrhiza had no effect on ginger height, tiller number, LCI or rhizome yield. Sustained high temperatures above 37°C, plus high light in the field caused dieback and stunted shoot growth in year two. There were no consistent effects of mycorrhiza or transplant type on rhizome nutrient content. Content of total Pb, As and other elements were at safe threshold levels for rhizome consumption. These results suggest that gingers grown from TCS2 transplants with at least three tillers yielded more rhizome than those grown from S1 transplants with fewer tillers. Introduction of ginger to a short season region such as the Delmarva may require consideration of environmental condition such as high temperature and light to which seedling transplants may be exposed in summer.</span>
基金Supported by Doctorate research foundation of Shanxi Academy of Agricultural Sciences(YBSJJ1303)
文摘In order to explore a new mulch-free maize planting mode and the best seedling age for maize transplantation in Shanxi early mature area,a field experiment was carried out using completely randomized block design. Taking mulch based direct sowing as the control group,effects of transplantation in different seedling age on maize growing process,plant height,yield and composition factors of maize were analyzed.Results indicate that growing process of maize seedlings transplanted in different seedling age is slightly slower than the control group. Transplantation has the effect of reducing plant height. Although the yield of transplanted maize in different seedling age is lower than the control group. Besides,with the growth of seedling age of transplantation,the gap is widening. However,it is expected to realize mulch-free maize planting by transplantation in Shanxi early mature area. The yield of maize transplanted in two-leaf seedling age is not significantly different from the control group,and the yield is only 9% lower than the mulch-based direct sowing( CK). In conclusion,two-leaf period is the best seedling transplantation age for maize in Shanxi early mature area in this experiment condition.
文摘“Rice transplanter” has brought a radical change in the method of rice seedlings transplanting in Bangladesh. The machine is gaining popularity with the increase of labor crisis during the peak period of transplanting, reduction time of in-between crops, rapid urbanization and industrialization, and changing socio-economic status of the farmers. Alternatively, the traditional way of rice transplanting is labor-intensive and involves high drudgery. Mechanical rice transplanter is cost-effective and operation-friendly. It is suitable to plant young seedlings maintaining plant to plant and line to line distance which plays an important role in increasing yield. Moreover, it is easy to take care of the crops planted in rows. It helps in maintaining soil physical properties and is considered to be better from a crop management and productivity point of view. In malignancy of having an edge over the traditional broadcasting, the adoption rate of mechanical transplanters is low due to high primary investment, lack of knowledge in growing mat type nursery, lack of repair and maintenance facility to the end-users, and unavailability of spare parts. Imparting these, available supply, entrepreneurship development, and encouraging custom hire services may be some of the practical results for adding the rice area under mechanical transplanting. This review summarizes the problems and prospects associated with seedling rice transplanting, technological gaps in the adoption of mechanical transplanters in a sustainable manner, and future ways to make transplanters more user-friendly and cost-effective.
基金supported by the Shandong Province Potato Industry Technology System Agricultural Machinery Project (SDAIT-16-10)Key R&D Program of Shandong Province,China (Grant No.2022CXGC010611)Jiangsu Planned Projects for Postdoctoral Research Funds (2020Z101).
文摘Side insertion horizontal transplanting sweet potato seedlings on mulch film is one kind of new planter pattern,which keeps the soil warm and moist restraining the infestation of pests and weeds,realizing dense transplanting and ensuring uniformity of sweet potato sizes.Therefore,a side insertion horizontal transplanting device for sweet potato seedlings on mulch film was designed,including the details and parameters of the reciprocating mechanism and the seedling clamping mechanism.Both the two mechanisms and the whole device were simulated and the test bench was built for field experiments to detect if this device can meet the agronomic requirements.The simulation results show that the designed device is in accordance with the agronomic requirements of horizontal transplanting,transplanting depth and transplanting length,and is potential for achieving rational close planting.The lateral length of the designed transplanting device is extended at about 90 mm compared with previous machine,which will promote the number of soil nodules of sweet potato seedlings and the growth of production enormously.The horizontal velocity of the transplanting claw is−17 mm/s when picking the seedling,the horizontal velocity of the transplanting claw 645 mm/s and the vertical velocity 83 mm/s when releasing the seedling.These data could ensure the accuracy requirements of horizontal transplanting trajectory.The field experiment results show the expulsion rate of sweet potato seedlings at 1.38%,the qualified rate of transplanting length and depth at 94.17%and 95.11%respectively,the average length and width of the mulch film breaking hole at 44.67 mm and 43.00 mm in several.The postures of the actual transplanted seedlings are consistent with the simulation results,meeting the requirements of horizontal transplanting with less damage to the mulch film.The designed transplanting device lays a foundation for the development of sweet potato seedlings side transplanting machine.