The origin,evolution, cultivation,dissemination, and diversification of Asian and African rices

Summary Available evidences drawn from biosystematics, evolutionary biology, biogeography, archaeology, history, anthropology, paleo-geology and paleo-meteorology are pooled to reconstruct the series of events that led to the cosmopolitan cultivation of the Asian cultivated rice (O. sativa) and the regionalized planting of the African cultigen (O. glaberrima) in West Africa. The genus Oryza originated in the Gondwanaland continents and, following the fracture of the supercontinent, became widely distributed in the humid tropics of Africa, South America, South and Southeast Asia, and Oceania. The two cultivated species have had a common progenitor in the distant past. Parallel and independent evolutionary processes occurred in Africa and in Asia, following the sequence of: wild perennialwild annualcultivated annual. The weed races also contributed to the differentiation of the cultivated annuals. The corresponding members of the above series are O. longistaminata Chev. et Roehr., O. barthii A. Chev., O. glaberrima Steud., and the stapfii forms of O. glaberrima in Africa; O. rufipogon Griff., O. nivara Sharma et Shastry, O. sativa L., and the spontanea forms of O. sativa in Asia.The differentiation and diversification of the annuals in South Asia were accelerated by marked climatic changes following the last glacial age, dispersal of plants over latitude or altitude, human selection, and manipulation of the cultural environment.Cultivation of rice began in many parts of South and Southeast Asia, probably first in Ancient India. Cultural techniques such as puddling and transplanting were first developed in north and central China and later transmitted to Southeast Asia. Wetland culture preceded dryland culture in China, but in hilly areas of Southeast Asia, dryland cultivation is older than lowland culture. The planting method progressed from shifting cultivation to direct sowing in permanent fields, then to transplanting in bunded fields.Widespread dispersal of the Asian cultigen led to the formation of three eco-geographic races (Indica. Sinica or Japonica, and Javanica) and distinct cultural types in monsoon Asia (upland, lowland, and deep water). Varietal types changed readily within the span of a millenium, largely due to cultivators' preferences, socio-religious traditions, and population pressure. Genetic differentiation developed parallel to the ecologic diversification process.The African cultigen developed later than the Asian cultigen and has undergone less diversification. The wild races in South America and Oceania retain their primitive features mainly due to lack of cultivation pressure or dispersal.Both the African and Asian rices are still undergoing evolutionary changes at habitats where the wild, weed, and cultivated races co-exist.     

Cities,Skills, and Inequality

ABSTRACT The surge in U.S. wage inequality over the past several decades is now commonly attributed to an increase in the returns paid to skill. Although theories differ with respect to why, specifically, this increase has come about, many agree that it is strongly tied to the increase in the relative supply of skilled (i.e., highly educated) workers in the U.S. labor market. A greater supply of skilled labor, for example, may have induced skill‐biased technological change or generated greater stratification of workers by skill across firms or jobs. Given that metropolitan areas in the U.S. have long possessed more educated populations than non‐metropolitan areas, these theories suggest that the rise in both the returns to skill and wage inequality should have been particularly pronounced in cities. Evidence from the U.S. Census over the period of 1950 to 1990 supports both implications.     

Resources,representation, and authority in Jharkhand,India

Abstract: Jharkhand is at the centre of India's struggles to define ‘the environment’ and ‘economically relevant natural resources’. Although cultural labels are applied by leaders who seek influence in these struggles as well as by many of those people who listen, an ethnonational analytic frame does not help answer the questions: How, why and when has the political idea of environment changed in India? When and why has the Jharkhand movement chosen violent tactics? When and why has the Jharkhand statehood movement realised electoral success? Or, why was Jharkhand state formed? To address such questions, a long range historical‐institutional approach is much more fruitful.     

Interdependence,Rules, and Rural Development

This paper explores land use conflicts between non-farm neighbors and farmers to illustrate the usefulness of the concepts of interdependence, rules, and property rights when doing rural development. Recognizing interdependence and its implications helps economic analysis focus on and understand the types of rules and institutions having the most influence on economic behavior, and thus identify policy alternatives. The resolution of land uses conflicts, for example, unavoidably changes the bundle of rights associated with land, andinfluences who can impose costs of whom; it makes a difference if a large farm has the right to produce odors, flies, or noise that reduces their neighbors' abilities to enjoy theneighbors' own land, or if instead, neighbors have the right to use their property without experiencing farm-produced odors, flies or noise the farm may be unable to use its own land for agriculture without being inconvenienced.     

Unemployment,Growth, and Trade Unions

This paper develops a two‐sector endogenous growth model with a dual labor market caused by the operation of trade unions. Trade unions strive for the extraction of rents from the growth generating imperfectly competitive primary sector. This union behavior results in a non‐competitive wage differential between the primary and secondary (perfectly competitive) sector. How the relationship between growth and unemployment depends on the institutional details of the labor market is analyzed. In general, growth and unemployment are intimately related for two reasons. Unemployment affects the scale of operation of the economy and thereby the growth rate. Growth affects inter‐temporal decisions of workers about where to allocate on the labor market once they are laid off, and thereby it affects equilibrium unemployment.     

Potato genetics,genomics, and applications

Potato has a variety of reproductive uniquenesses besides its clonal propagation by tubers. These traits are controlled by a different kind of genetic control. The reproductive information has been applied to enable interspecific hybridization to enhance valuable traits, such as disease and pest resistances, from the tuber-bearing Solanum gene pool. While progress has been made in potato breeding, many resources have been invested due to the requirements of large populations and long time frame. This is not only due to the general pitfalls in plant breeding, but also due to the complexity of polyploid genetics. Tetraploid genetics is the most prominent aspect associated with potato breeding. Genetic maps and markers have contributed to potato breeding, and genome information further elucidates questions in potato evolution and supports comprehensive potato breeding. Challenges yet remain on recognizing intellectual property rights to breeding and germplasm, and also on regulatory aspects to incorporate modern biotechnology for increasing genetic variation in potato breeding.     

薏苡氮磷钾养分吸收分配及利用特征

旨在为薏苡科学施肥及高产潜力挖掘提供理论依据。以4个薏苡品系为试验材料,于2018—2019年进行大田试验,分析其在不同生育时期氮磷钾(NPK)元素的吸收、分配及利用规律。结果表明,4个薏苡品系的全株总生物量干重在20.5~24.7 t/hm²,地上部分生物产量干重在18.4~22.6 t/hm²之间,但是籽粒产量相对偏低,产量为1969.2~3109.1 kg/hm²。从薏苡抽穗至籽粒成熟,整个植株对NPK元素的吸收和积累量均有增加;N元素在抽穗至扬花期主要分布在茎鞘和叶片,至完全成熟籽粒中N素积累及分配均高于其他部位,而PK元素则主要分配在茎鞘部位。薏苡植株总NPK的吸收量平均为183.93 kg/hm²、62.57 kg/hm²和320.56 kg/hm²,平均吸收比例为N: P: K=2.94: 1: 5.12。薏苡NPK元素的籽粒生产效率和收获指数相对偏低,每100 kg籽粒对NPK养分需求量分别为5.6~7.3 kg,1.7~2.4 kg,8.0~15.0 kg。4个薏苡品系整体物质累积能力强、生物量大,但籽粒对NPK吸收分配和利用效率相对较低,高产潜力的挖掘仍有很大的提升空间。     

不同花生品种氮磷钾钙硫吸收、分配和利用的差异

通过大田随机区组试验,研究优化施肥条件下,不同花生品种氮磷钾钙硫吸收、分配和利用的差异,旨在为豫南花生产区不同品种花生合理施用氮磷钾钙硫肥提供技术支撑。结果表明,花生仁中氮(N)、磷(P)、硫(S)含量最高,其中,‘驻花1号’的N、‘开农71’的P、‘冀花13’的S含量最高,分别为5.150%、0.558%、0.277%;花生茎叶中钾(K)、钙(Ca)含量最高,其中‘中花16’茎叶中K、‘中花24’茎叶中Ca含量最高,分别为1.637%、0.940%。花生仁中N、P、S积累量最高,其中,‘豫花40’花生仁中N、P、S积累量最高,分别为288.436、25.505、15.263 kg/hm²;花生茎叶中K、Ca积累量最高,其中‘豫花37’、‘中花24’茎叶中K、Ca积累量最高,分别为80.760、54.084 kg/hm²。每形成100 kg荚果需求的N、P₂O₅、K₂O、CaO、S养分量分别3.920~5.042、0.905~1.293、1.626~2.721、0.777~1.150、0.270~0.343 kg。本试验条件下,每形成100 kg荚果,‘豫花22’需求的氮最低,‘中花24’需求的磷最低,‘商花5号’需求的钾、钙、硫最低;‘驻花1号’需求的氮最高,‘开农71’需求的磷、钾、硫最高,‘中花24’需求的钙最高。     

Addition, Subtraction, Multiplication, Division, Involution and Factorial of High Effective Locations

This paper presents the class of high effective locations and its addition, subtraction, multiplication, division, involution and factorial by the object-oriented programming.     

Blood,timber, and the state in West Kalimantan,Indonesia

Abstract: West Kalimantan (West Borneo) has a history of violent communal conflict.¹ It also has extensive forests that have been looted for decades. The argument will be that these two are linked, but not by the grievances of the forest dwellers. Except in its first few days, the two main episodes of 1997 and 1999 were not driven mainly by grievances among marginal groups. Rather, explanations based on the ‘resource curse’ carry more weight. These focus attention on the contested nature of the state, rather than on rebellious activities of marginal groups. When state institutions were thrown into disarray by the sudden resignation of President Suharto in 1998, Dayak militants already close to state power rewrote the rules of local politics by demonstratively ‘cleansing’ certain areas of an unpopular immigrant minority. This theatrical manoeuvre impressed political rivals sufficiently to allow Dayaks to gain control over several timber‐rich districts, which had a thriving black economy. Malays later imitated these techniques to stem the tide.     

Immigration,Migration, and State Redistributive Expenditures

The effect of immigration on state and local budgets is a frequent topic of both political and academic conversations. A controversial issue among scholars is whether or not immigration induces outmigration of low income native born residents, a population movement which would potentially have implications for the jurisdictional distribution of immigration's fiscal impact. It is hypothesized here that if interstate poverty migration occurred, it should cause fiscal spillovers by distributing some of the public sector burden of immigration from immigrant “host” states to neighboring states. This paper uses cross‐sectional state data from 1988–1995 to explore the relationship between immigration in neighbor states and state redistributive expenditures. The results suggest that there is a positive relationship between immigration to neighboring states and redistributive expenditures. While most discussion of the fiscal impact of immigration has focused on the effects on host states and localities, the implications of these findings are that there are fiscal spillovers to neighboring states, suggesting that fiscal impacts on host states have been over‐estimated and effects on neighboring states have been underestimated. Additionally, the implications of recent welfare reform, which gives states the opportunity to use citizenship as a criterion for program eligibility, are discussed.     

Technology,Industrial Restructuring,and Regional Development

ABSTRACT This paper presents a contemporary survey and synthesis of research on the regional dimensions of technology and competitiveness and explores ways in which technological change has influenced industrial restructuring in U.S. regions. Neoclassical models of regional growth are judged to be seriously wanting in their treatment of technological change. Industrial organization theories such as product/profit cycles, best-practice firms, and flexible specialization have proven to be more illuminating. However, the task remains to integrate technology as a core element in a geography of production and regional economic change that includes both global strategic decision-making of companies and the viability of plants in particular regional settings. Although the federal government as sponsor and procurer of technology has contributed significantly to regional industrial restructuring, the prospects for state and local governments to facilitate technological change appear to be very limited.     

不同蔬菜对重金属汞、铬、砷、镉、铅积累效应的研究

为了对辽宁省葫芦岛龙岗区蔬菜生产基地蔬菜生产结构的调整提供科学的参考,采用原子吸收的方法,对该生产基地的土壤与蔬菜中重金属(Hg、Cr、As、Cd、Pb)的含量进行检测。结果表明：该蔬菜基地土壤中Hg的含量平均为0.42 mg/kg,Cr的含量平均为52.20 mg/kg,As的含量平均为34.92 mg/kg,Cd的平均含量为0.93 mg/kg,Pb的含量平均为98.49 mg/kg,说明该地区的土壤中重金属含量基本符合农业生产的要求;该蔬菜基地蔬菜中Hg的含量平均为0.92 μg/kg,Cr的含量平均为120.09 μg/kg,As的含量平均为13.80 μg/kg,Pb的含量平均为94.17 μg/kg,Cd的平均含量为15.65 μg/kg,并且所测定的蔬菜样本中甘蓝在5种重金属的含量上均比其他蔬菜的含量高,但也能符合国家卫生标准。此实验可为该蔬菜区蔬菜生产结构的调整提供一定的参考。     

Optimum allocation of plots to years,seasons, locations,and replications,and its application to once-over-harvest cucumber trials

Summary Large experiments and breeding trials are often conducted over years, seasons (or planting dates), and locations, and with replication (blocks). This is costly and time-consuming, but it is usually deemed necessary to sample a range of environments. In this paper, we describe a general approach to optimum allocation of sampling effort, and apply it to once-over-harvest cucumber trials. Two criteria for optimality are considered: minimizing the variance of a genotype (or treatment) mean, and minimizing cost per unit information. Costs could include penalties for delaying a breeding program. Thus, costs may depend on the goal, as well as the size, of the experiment or breeding trial.We found that efficient allocation of resources favors using more years and/or season, with fewer locations and/or replications. Using more years with fewer locations and/or replications is suggested when genotypes are to be evaluated by yield alone. When both yield and quality variables are of interest, as is likely, using more seasons with fewer locations and/or replications is recommended.Paper No. 11302 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, North Carolina, USA 27695–7601.     

Potential Yields and On-Farm Ethanol Production Cost of Corn, Sweet Sorghum, Fodderbeet, and Sugarbeet

Field experiments were conducted during 1980-82 at the Agronomy Farm of the University of California, Davis, to compare fermentable carbohydrate production and cost of potential ethanol from fodderbeet, sweet sorghum, sugarbeet, and corn in relation to the requirements of these crops for fertilizer nitrogen and irrigation. The response of hexose yields of these crops to fertilizer N varied in the two experiments. When all crops responded, sweet sorghum and sugarbeet required 36 % and fodderbeet 68 % of the fertilizer N needed for corn. Twelve weeks following a mid-season irrigation cut off, hexose yield of sugarbeet was decreased by 18 % as compared to an adequately watered crop. Water stressed sweet sorghum extracted higher amounts of soil moisture, increased in hexose concentration and produced 29 % higher hexose yield than when adequately watered. Stressed sugarbeet, however, had a higher hexose yield due to its higher sugar concentration.
When fertilized and irrigated adequately, fodderbeet produced 13.4, sugarbeet 11.9, sweet sorghum 10.0, and corn 8.15 Mg hexose ha⁻¹. Comparative on-farm ethanol production costs of these four crops were very close ($0.38 to 0.40 L⁻¹). Thus, growing established crops like corn and sugarbeet for which processing facilities and alternative markets already exist would be preferred.