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1.
为提高大豆育种试验的准确性,降低劳动强度,针对垄三栽培小区试验农艺技术要求,设计了一种与之配套的垄上双行插装式排种器,并以作业速度和株距为影响因素对其工作性能进行了测试。结果表明:当作业速度分别为3.6、4.5、5.4 km.h-1,双行株距为5 cm时,其粒距合格指数≥85.17%、重播指数≤11.11%、漏播指数≤4.24%、变异系数≤20.69%;当双行株距为7.5 cm时,其粒距合格指数≥85.26%、重播指数≤9.47%、漏播指数≤5.26%、变异系数≤18.17%。两种工况下,排种器均达到JB/T51017-1999《中耕作物精密播种机产品质量分等》优等品标准的要求。该排种器为垄三栽培模式配套大豆小区精密播种机的开发奠定了基础。  相似文献   

2.
为保证2BMFJ-3型麦茬地免耕大豆精密播种机播种大豆的性能,确定一种适合于该播种机的机械式精密排种器,参照GB6973-2005《单粒(精密)播种机试验方法》,以窝眼轮式、倾斜勺式和勺轮式排种器为研究对象,在JPS-12计算机视觉精密排种器性能检测试验台上实施了对比试验研究.结果表明:在作业速度3 ~6 km·h-1、粒距8 cm条件下,勺轮式排种器的排种性能最优,其合格指数87.8%~98.9%,重播指数0.5% ~1.1%,漏播指数低于12%,变异系数小于16%,各项指标均达到国家标准优等品水平.  相似文献   

3.
以设计的气吸式大豆高速精密排种器为研究对象,采用响应面法试验设计方法,以吸孔直径、真空度、作业速度和吸孔数为影响因素,以合格指数、漏播指数、重播指数、变异系数为目标函数,运用Design Expert 7.0试验设计软件进行处理,建立排种器主要性能指标与试验因素之间的数学模型,分析试验诸因素对排种器性能指标影响规律及交互效应关系。优化得出最佳参数组合吸孔直径4.5~5.0 mm、吸孔数75~85个、真空度5 k Pa、作业速度9 km·h-1时,此时合格指数大于96,漏播指数小于1.5,重播指数小于2.5和变异系数小于20。  相似文献   

4.
2BMFJ-3(B)型茬地大豆免耕覆秸精播机性能试验研究   总被引:1,自引:0,他引:1  
按照国标标准《GB/T6973-2005单粒(精密)播种机试验方法》,设定理论株距8cm和6cm,理论播深3~5cm,对2BMFJ-3(B)型茬地大豆免耕覆秸精播机进行田间性能测试,进而对其作业质量进行等级评定。结果表明:当理论株距为8cm和6cm时,粒距合格指数、重播指数、漏播指数及株距变异系数均达到了国家部颁标注优等品要求水平;当理论播深为3~5cm时,播深合格率达到一等品的要求水平。  相似文献   

5.
从大豆种子的株距、播深和施肥位置三个方面测试小麦茬地免耕大豆精密播种机的工作性能,并做了田间试验,结果表明:该机株距合格指数可达68.4%,重播指数为13.4%,漏播指数为18.1,变异系数为26.3,播深合格率为87.7%,达到了<中耕作物精密播种机产品质量分等>标准中关于一等品的要求.同时,施肥位置也满足农艺要求.  相似文献   

6.
《中国马铃薯》2013,(2):112-118
为提高脱毒微型马铃薯机械化播种水平,保证播种质量,针对脱毒微型马铃薯,设计了一种气力式倾斜圆盘排种器,并对其进行了单因素试验及正交试验。分析了该排种器合格指数、重播指数、漏播指数和变异系数等性能指标与排种轴转速、排种盘倾斜角度、排种盘型孔形式3个要素之间的关系。单因素试验结果表明,上述3个试验因素对排种器性能指标均有显著影响;正交试验结果表明,排种轴转速为10 r/min、排种盘倾斜角度为45°、排种盘型孔形式为9×Φ12 mm圆柱孔时,排种器合格指数达97.62%,漏播指数为0.67%,变异系数为8.94%;研究结果表明,气力倾斜圆盘排种器能满足大粒径且外形个体差异性大的脱毒微型马铃薯的精密播种要求,为大粒径种子的播种提供一个新的方法。  相似文献   

7.
对品种的适应性是大豆育种专用排种器技术研究的关键,主要取决于大豆种子与排种盘型孔间的关系,因此,如何精准构建排种盘型孔参数关于大豆种子物理参数的数学模型具有非常重要的意义。本研究基于东农52大豆种子的物理参数,理论分析并确定其各种型孔充填状态的型孔均径比范围(1.43~1.87)及对应状态概率。建立了大豆小区育种插装式排种器的EDEM仿真模型,并以型孔均径比及充种倒角为试验因素,漏播率及重播率为试验指标,进行了二因素五水平二次回归通用旋转组合设计试验,建立了试验指标的数学模型,以优化型孔的最佳结构参数。结果表明:对漏播率,型孔均径比极显著(P0.01),充种倒角显著(0.01P0.05);对重播率,型孔均径比极显著(P0.01),充种倒角有一定影响(0.05P0.1)。在试验范围内,随型孔均径比的增大,漏播率减小及重播率增大,随充种倒角的增大,漏播率先减小后增大,重播率无变化。型孔最佳参数为型孔均径比1.64,充种倒角1.54 mm,此时,漏播率4.95%,重播率6.49%。验证试验结果表明:优化型孔的排种盘具有相对最佳的作业性能。该研究为其它作物排种器型孔的设计研究提供了参考。  相似文献   

8.
2BMFJ-BL5型原茬地大豆免耕覆秸精量播种机性能试验研究   总被引:3,自引:0,他引:3  
在北方垄作秸秆根茬残留量为0.994 kg·m~(-2)的人工收获后玉米原茬地上,测试分析2BMFJ-BL5型大豆原茬地免耕覆秸精量播种机田间作业性能。在作业速度5 km·h~(-1)条件下,按照中华人民共和国机械行业标准NY/T1768-2009《免耕播种机质量评价技术规范》实施了本次试验。结果表明:播种均匀性达到了国家标准优等品标准,播种深度合格率达到了国家一等品的标准。各行排肥量一致性变异系数达到了国家一等品的标准,总排肥量稳定性变异系数达到了国家优等品的标准。秸秆清秸率达97%以上,植被覆盖率达97%以上,田间出苗率达94%以上。试验结果为2BMFJ-BL5型大豆原茬地免耕覆秸精量播种机的产业化和推广应用提供了理论依据。  相似文献   

9.
《花生学报》2012,41(1):15-15
最近,由烟台市农机所承担的烟台市科技攻关项目《气吸式花生精量播种机的研究与开发》已顺利通过市级鉴定。烟台市农机所自主研发了垂直园盘排种器,在机械式花生播种机的基础上进行集成创新,研发出了2BHQ-2型气吸式花生精量播种机,申报了国家实用新型专利二项(201120314142.7,201120314143.1)。该机应用气吸式工作原理,可一次完成起垄、开沟、施肥、排种、喷药、覆膜、覆土压膜等作业功能,具有种子适应范围宽、损伤率低、播种精度高等优点,节约了种子,提高了出苗率和机具播种的适应性。  相似文献   

10.
为了实现大豆单粒精密排种,从而节约种子用量,使用EDEM软件设计内充种式大豆排种器,针对5个黄淮海地区普遍种植的大豆品种,对内充种式大豆排种器的性能进行仿真试验,分析排种器工作转速对排种器的单粒率的影响,并进行台架试验验证.结果显示:仿真试验中排种器工作转速在30 r·min-1时单粒率为90.81%~95.42%.台架验证试验中排种器工作转速对单粒率有明显影响,排种器转速在30 r·min-1时,5个品种大豆种子的单粒率为89.88%~94.13%,重播率为4.75%~9.61%,漏播率为0.12%~2.04%,试验值均符合排种器的工作性能行业标准.仿真结果与台架试验结果最大误差仅为4.39%,该仿真设计可以为排种器关键零部件的优化提供理论依据.  相似文献   

11.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

12.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

13.
The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.  相似文献   

14.
SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.  相似文献   

15.
Plains rough fescue ( F estuca hallii) is an important forage grass species in western Canada. Seed for use in pastures and ecological restoration is in high demand but supply is limited because F. hallii is an erratic seed producer. Seed producers require an understanding of the factors that influence flowering and seed set in this species. The aim of this study was to assess the effect of irrigation and nitrogen fertilization on the flowering and growth of F. hallii in a native rough fescue prairie in Alberta, Canada. Irrigation had a strong positive effect on seedhead density, whereas fertilization had limited effects on growth and reproduction of F. hallii. These results demonstrate that under field conditions, available moisture is likely to be a key factor driving flowering and seed production in F. hallii.  相似文献   

16.
Summary

Within the last three decades, the rice-wheat cropping system has triggered, and with time, aggravated soil micronutrient deficiencies in the Indo-Gangetic Plains (IGP). This has largely been due to the shift from an earlier rice and wheat monoculture with low yielding, long duration indigenous varieties, to an intensive rice-wheat rotation cropping system with short duration modern high yielding varieties on the same piece of land. The problems related to micronutrient deficiency in the IGP are more due to the size of its available pools in the soil rather than its total contents and are greatly influenced by crop management, or rather its mismanagement. Deficiency of zinc is widespread in the IGP, but with the extensive use of zinc sulfate, zinc deficiency has reduced in some areas of the region. Meanwhile, the deficiency of Fe, Mn and B has increased in the IGP. Deficiency of Cu and Mo is location specific and can limit rice and wheat yields. The adoption and spread of the rice-wheat system in permeable coarse textured soils, particularly in the western IGP, not only caused iron deficiency in rice but also resulted in the emergence of manganese deficiency in wheat. In highly calcareous and acidic soils, boron is the next limiting micronutrient in crop production after zinc. Bumper rice and wheat harvests in the past decade, the declining use of organic manures in the region and except for the widespread use of zinc sulfate, a general lack of awareness amongst farmers on micronutrient deficiency problems has contributed to micronutrients limiting rice and wheat yields in the IGP. Approaches to alleviating micronutrient deficiencies include matching the crop removals of the micronutrients with its replenishments through their respective external carriers, supplementation through organic sources and mobilization/utilization through cultivation of micronutrient efficient crop cultivars. Identification of efficient micronutrient carriers and finding the optimum rate, mode and time of its application is important in ameliorating the micronutrient deficiencies. This article reviews the extent of micronutrient deficiency and discusses various management options available to reduce micronutrient deficiency induced crop yield reduction for rice and wheat in the Indo-Gangetic Plains.  相似文献   

17.
Marine biomass diversity is a tremendous source of potential anticancer compounds. Several natural marine products have been described to restore tumor cell sensitivity to TNF-related apoptosis inducing ligand (TRAIL)-induced cell death. TRAIL is involved during tumor immune surveillance. Its selectivity for cancer cells has attracted much attention in oncology. This review aims at discussing the main mechanisms by which TRAIL signaling is regulated and presenting how marine bioactive compounds have been found, so far, to overcome TRAIL resistance in tumor cells.  相似文献   

18.
Summary Morphological and biochemical parameters that could be involved in resistance to late blight were studied in non-infected and in infected potato hybrids resulting from a cross betweenSolanum phureja, resistant toPhytophthora infestans, and a susceptibleSolanum tuberosum. Some morphological differences between resistant and susceptible hybrids, indicating a positive correlation between stem diameter and phloem thickness in the stem and resistance toP. infestans, were observed. The lignin content in the leaves of the resistant hybrid rose upon infection byP. infestans. In the leaves of the susceptible hybrid, a diminution of the lignin content could be observed upon infection byP. infestans. In the same context, peroxidasic activity raised upon infection byP. infestans in both resistant and susceptible hybrids. Further characterization of the hybrid clones based on the polymorphism of peroxidases was attempted using isoelectric focusing.  相似文献   

19.
Potato is an important crop, grown worldwide. It suffers from many pests and diseases among which late blight, caused by the oomycete Phytophthora infestans, is the worst. The disease is still causing major damage in many potato production areas and control is only possible by applying fungicides frequently. The knowledge on the molecular biology and genetics of the interaction between the plant and the oomycete is developing rapidly. These are relevant fields of study, currently dominated by the discovery of many resistance genes and numerous effector proteins and the analysis of their specific mode of action. These studies may yield essential information needed for the development of durable resistance. The long-term and worldwide effort to breed for resistance so far has had little effect. A novel breeding approach may change this. It is based on cisgenic modification (CM) consisting of marker-free pyramiding of several resistance genes and their spatial and temporal deployment yielding dynamic varieties that contain potato genes only. It is envisioned that this CM approach with potato’s own genes will not only prove societally acceptable but may also result in simplifications in the legislation on use of the CM approach. Various parties in the potato research arena intend to cooperate in this novel approach in a number of developing countries where potato substantially contributes to food security. The use of resources such as land, water and energy improves when the effect of late blight is markedly reduced.  相似文献   

20.
In an experimental breeding scheme to improve late blight (Phytophthora infestans) and white potato cyst nematode (Globodera pallida) resistance of tetraploid potato over three generations of crossing and selection, 15 clones survived the final selection, and these were derived from 15 great-grandparents. There was no direct selection for resistance to Potato virus Y (PVY), but 14 out of the 15 great-grandparents were resistant to PVY and three had extreme resistance. Thirteen of the 15 descendants had PVY resistance and one extreme resistance. This was within the range expected for a random (unselected) sample from the genotypes of the great-grandparents. Hence, we found no evidence for any positive or negative association between PVY resistance and the attributes selected. The conclusion is that laborious selection is not required in every generation when many parents have PVY resistance, including some with more than one copy of a PVY resistance gene or resistance at more than one locus. However, in the future, determining the major virus resistance genes present in potential parents in each generation using diagnostic molecular markers would prevent susceptible × susceptible crosses being made and maximise the number of resistant × resistant ones.  相似文献   

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