冀西北高寒半干旱区青饲料作物品种比较试验研究

[目的]筛选适合冀西北地区的优质高产青饲料作物品种。[方法]采用随机区组设计,对6个青饲料品种(农大108(CK)、巡青518、乐食高丹草、墨杂1号青饲玉米、墨西哥玉米和百绿001青贮玉米)进行比较试验,筛选适合冀西北高寒半干旱区的青饲料作物新品种。[结果]墨杂1号青饲玉米和百绿001青贮玉米的鲜草产量最高,分别为49 830和46 620 kg/hm2,比对照增加42.1%和32.9%。百绿001和墨杂1号的青饲性状明显优于其他品种,其生育期也较长。除墨西哥玉米外,其他品种在生育期内均有较强的抗病性和抗干旱性。墨杂1号青饲玉米干物质产量最高,达12 510 kg/hm2。[结论]墨杂1号青饲玉米和百绿001青贮玉米综合表现较好,适宜在冀西北高寒半干旱区种植,而墨西哥玉米不适合在该区种植。     

Socio-economic and environmental changes related to maize richness in Mexico’s central highlands

The occurrence of genetic erosion in local maize varieties in Mexico is intensely debated. Recent publications from Mexico show contradicting results about the loss of local varieties. Genetic erosion is a complex process, and well-documented examples of actual genetic erosion are not common in the literature. We worked in a region in which adoption of improved varieties was negligible, but other factors affecting maize agriculture were at play. The objectives of the study were to describe changes in maize diversity in the last 10 years and to associate them with socio-economic and environmental changes in a region in Mexico’s Central Highlands. We used richness and abundance of local varieties and diversity indices of races as indicators of maize diversity changes over time. We analyzed statistics and based on interviews we evaluated maize diversity changes between 2005 and 2015. We interviewed 113 farmers on two occasions with intervals from 5 to 10 years. According to climate statistics, rain has declined and temperature has increased. We also found a decrease in the lake level during the past 35 years. The total population in the region has doubled since the 1960s. The indigenous population has not changed significantly. Number of people working in agriculture has decreased since the 1960s. Rain fed agriculture decreased 8.1 % from 1990 to 2007. In four villages studied, farmed land area had decreased between 1995 and 2015. This reduction varies between 22 and 39 % depending on the village. Maize planted area decreased from 9675 to 8115 ha from 2003 to 2014. In the same period, avocado plantations grew from 34 to 786 ha. In despite of these changes, we did not find significant changes in average landraces per farmer (2.13 ± 0.28 in 2015) nor per village (4.15 ± 1.26 in 2015). Significant changes in maize races were not found either (1.91 ± 0.26 per farmer, 2.85 ± 0.86 per village in 2015). These results show that maize landrace diversity in the region is resilient but dynamic.     

吉林省玉米品种容重浅析

选择吉林省目前生产中应用的140个玉米品种,分为早熟组、中熟组、中晚熟组、晚熟组、耐密组、高油组、青贮组和特用组共8组,在吉林省中部半湿润区、西部半干旱区设3个试验点,系统地研究了吉林省玉米品种容重概况,通过在生态区间、品种组间、品种组内计算与分析,获得了各品种的容重差异及容重显著高于对照的高容重玉米品种。     

Silenced voices,vital arguments: smallholder farmers in the Mexican GM maize controversy

Smallholder producers are the collective most likely to be affected by the introduction of GMOs globally, yet the least included in public debates and consultation about the development, implementation or regulation of this agricultural biotechnology. Why are the voices and arguments of smallholder farmers being excluded from national and international GM debates and regulation? In this article, we identify barriers which prevent smallholder farmers in Mexico from having a voice in public political, economic, scientific and social fori regarding the GM maize controversy. Through the analysis of empirical data from a case study in Mexico, we identify political, institutional, economic and ontological reasons that lie behind that exclusion. We conclude with an appraisal of smallholder farmers’ perspectives on GM maize and their visions of Mexico’s rural future, within which they demand a meaningful and rightful space.     

不同玉米品种对小斑病强致病力菌的抗病性检测

通过对28个玉米品种进行田间强致病力菌株接种,鉴定了其抗病性。结果表明：不同玉米品种对玉米小斑病的抗病性存在差异,28个玉米品种中大多数玉米品种属于抗或者高抗水平;只有冀玉12号、鲁单9056、郑单958和先玉335属于中抗品种,而这些品种推广面积较大,是玉米主产区的主流品种,建议严密监测小斑病菌的致病性,尽快筛选对强致病力菌株抗性好的高产玉米品种。     

Prehispanic adaptation in the ixtapalapa region, Mexico

Data accumulated during an intensive survey of Prehispanic settlements in the Ixtapalapa Peninsula region enables me to formulate hypotheses regarding the nature of sociocultural change and adaptation during the Prehispanic period. A summary of these hypotheses follows. The Early and Middle Formative period was a time of low population, when most communities were located on or near the agriculturally productive lakeshore plain zone. During the subsequent period, attendant upon the development in the central highlands of more productive varieties of maize, population increased, and for the first time the agriculturally marginal piedmont zone was colonized. This process may have resulted in the enhancement of status differentiation in these societies because some communities maintained access to the preferred land along the lakeshore plain zone. Also, occupation of a variety of environmental zones may have encouraged symbiosis, which could have further enhanced status differentiation as some individuals or groups became the focuses of exchange networks. During the Late Formative period, developments along this line proceeded throughout the Valley of Mexico, but later, during the Terminal Formative period, some groups prospered more than others because they were favorably situated for the construction of large-scale irrigation systems. The foremost example of the latter is Teotihuacan, which eventually dominated the population of the Ixtapalapa Peninsula region, as well as the remainder of the Valley of Mexico and probably adjacent groups in the central highlands. From A.D. 0 to A.D. 700, the region was dominated by Teotihuacan. This was a period of low population and apparently rural settlement patterns. A similar situation existed during the Late Toltec period as Tula dominated the region. I suggest that Teotihuacan and Tula had similar relationships with their rural peripheries; specifically, they were largely extractive and so dominated rural populations that they were the only important focuses of exchange and craft specialization. Population declined in the rural areas in part because they were too far from the urban centers to participate effectively in the exchange networks. In contrast, the Aztec period was characterized by the presence of a number of urban centers scattered widely over the valley; these centers served as the focuses of exchange and specialization. A similar situation may have characterized the Early Toltec period. During the Aztec period, the combination of intensive local and valleywide symbiosis plus the introduction of chinampas allowed the population to reach the greatest density of the Prehispanic period.     

43个玉米品种在新疆吐鲁番旱区表现和抗旱类群划分

目的 基于形态指标和产量指标,将43份引进玉米品种划分为不同群体,并筛选出适合新疆旱区种植的玉米品种。方法 以43个玉米品种为材料,测定其在干旱胁迫下株高、穗位高、茎粗、单株穗数、穗长、穗粗、穗行数、穗粒重、百粒重、籽粒产量以及茎叶鲜重和茎叶干重等12项指标。运用相关分析、主成分分析、聚类分析、逐步判别分析和多元方差分析等方法综合评价多个玉米品种的抗旱性能。结果 12项数量性状间存在一定的相关性和信息的重叠,35对数量性状的相关系数达极显著水平,21对数量性状相关系数达到显著水平。前3个主成分代表了43个玉米品种的12项数量性状71.02%的信息,其贡献率分别为27.49%、27.41%和16.12%。其中,第一主成分是营养体生长状况,包括株高、穗位高、茎粗和茎叶重量;第二主成分是生殖生长状况,包括穗数、穗长、穗粒重、百粒重和产量;第三主成分是穗行数和穗粗。当类间距离为4.5时,43个玉米品种被聚为5大类。其中,第Ⅱ类属于高产品种,包含3个品种;第Ⅲ类属于中高产品种,包含7个品种;第Ⅳ类属于中产品种,包含10个品种;第V类属于中低产品种,包含19个品种;第Ⅰ类属于低产品种,包含4个品种。42个玉米品种被正确判别,判对概率为97.67%;1个玉米品种被误判,误判率为2.33%。结论 类群划分的结果准确可靠,选育的第Ⅱ类和第Ⅲ类玉米品种能够显著的增产,玉米育种在抗旱性方面进展明显。玉米正播模式引种,辽单145和辽单1211;复播玉米品种郑单958最佳。     

一年两季鲜食糯玉米区域试验的GGE双标图分析

[目的]综合评价广西一年两季鲜食糯玉米区域试验品种基因型及基因型与环境互作的关系,为玉米区域试验和育种工作提供参考.[方法]应用GGE-biplot对广西2016年春季和秋季鲜食糯玉米区域试验的鲜穗产量进行GGE双标图分析,评价参试玉米品种的丰产性、稳产性和适应区域,以及各承试点的代表性和鉴别力.[结果]参试玉米品种与环境的综合评价分析结果表明,多数试点间存在正相关,其中春季试验北海和玉林及秋季试验北海和柳州试点间存在紧密正相关,对品种产量排序的影响相似.参试玉米品种适宜环境的分析结果表明,春季7个试点可分为4个生态区,秋季7个试点可分为3个生态区,直观展示了品种的适应性.参试品种丰产性和稳定性的分析结果显示,春季品种桂W1518和秋季品种百香糯1601在当季具有较好的丰产性和稳定性.环境鉴别力与代表性分析结果表明,春季柳州和南宁试点为较理想的试验环境,秋季玉林和河池试点为较理想的试验环境.[结论]GGE双标图直观展示了参试玉米品种的丰产性、稳产性和适应性,以及承试环境的鉴别力、代表性和生态类型,对玉米区域试验和育种工作具有重要参考价值.     

不同光照条件下玉米碳酸酐酶活性差异比较与分析

[目的]比较不同光照条件下不同玉米品种碳酸酐酶（CA）活性的变化情况。[方法]以毕单系列玉米品种（毕单10、13、15、17、18号）为试材,待幼苗长至34叶时在不同光照条件（＂弱光＂、＂中光＂、＂强光＂）下培养,培养3 d后开始取样测定CA活性,研究不同处理玉米品种CA活性的变化规律。[结果]在＂弱光＂至＂中光＂段,随着光照强度的升高,各品种的CA活性逐渐升高,但在＂中光＂至＂强光＂段,各品种的CA活性普遍下降,其中毕单15号CA活性降幅最大,毕单18号CA活性降幅最小。＂弱光＂和＂中光＂处理各品种的CA活性差别较小,而＂强光＂处理各品种的CA活性差别较大。[结论]在一定范围内,供试玉米品种的CA活性随光照强度的增加而升高。     

陕西商洛春玉米品种密度施肥试验

春玉米品种、密度、施氮量、施磷量四因素三水平试验表明,密度是影响洛南川道地玉米产量的主要因素,品种对玉米经济性状和农艺性状的改善具有显著作用。试验最优处理组合为A3 B3 C1 D2,即品种掖单19,密度6.0万/hm2,施氮量255 kg/hm2,施磷量75 kg/hm2。     

不同甘薯品种套作玉米下的群体产量及效益分析

以7个不同甘薯品种为试验材料,采用随机区组设计,研究其在套作玉米下的群体产量优势和经济效益。结果表明:套作模式下,甘薯产量较净作降低,不同甘薯品种间的单株薯数、单株薯重、产量差异显著,套作南薯88、徐薯22和渝薯2号甘薯所得产量及淀粉产量均较高;7个不同甘薯品种套作玉米种植下的复合群体土地当量比均大于1,均存在套作优势;以净作和套作宁4-6、济黑薯1号和E08101等特用型甘薯所得产值较高。     

云南巍山县青贮饲草品种筛选*

 对13个青贮饲草品种进行了物候期、产草量、茎叶比、干鲜比、营养成分和采食率等方面的测定。结果表明:先锋高丹草、大力士甜高梁、M-81E甜高梁的干物质产量显著高于玉米类品种,而玉米类品种中以东龙一号玉米、丹科2143玉米、东陵白玉米、曲晨三号玉米表现较好。大力士甜高粱、东龙一号玉米、先锋高丹草、墨西哥类玉米4个饲草品种的干物质产量较高,适应性强,适宜在云南亚热带地区作青贮饲草品种推广种植。     

云南巍山县青贮饲草品种筛选

对13个青贮饲草品种进行了物候期、产草量、茎叶比、干鲜比、营养成分和采食率等方面的测定。结果表明:先锋高丹草、大力士甜高梁、M-81E甜高梁的干物质产量显著高于玉米类品种,而玉米类品种中以东龙一号玉米、丹科2143玉米、东陵白玉米、曲晨三号玉米表现较好。大力士甜高粱、东龙一号玉米、先锋高丹草、墨西哥类玉米4个饲草品种的干物质产量较高,适应性强,适宜在云南亚热带地区作青贮饲草品种推广种植。     

小麦、玉米不同品种对单嘧磺隆的敏感性研究

采用模拟添加法研究了小麦、玉米对单嘧磺隆的敏感性。结果表明：供试小麦、玉米不同品种对单嘧磺隆的敏感程度存在一定差异，在 6个小麦品种中辽春 10号对单嘧磺隆耐药性最强，京 8335表现最敏感：在 7个玉米品种中农大 108、唐抗 5号对单嘧磺隆耐药力最强，而唐玉 5号最敏感。小麦对单嘧磺隆的耐性比玉米高得多，种根比种芽敏感性高。另外，玉米对单嘧磺隆的敏感性与种子触药时期有关。     

紧凑型玉米杂交种形态生理学研究进展

从国内外玉米生产形势上看,种植密度是提高玉米产量的重要栽培措施之一,在种植密度较高的地区,更宜种植紧凑型玉米品种来获得较高的籽粒产量。本文结合国内外学者研究结论,从群体冠层形态结构和光合生理角度,比较了紧凑型玉米品种与平展型玉米品种差异,系统阐述了紧凑型玉米品种产量提高的形态生理学基础,为紧凑型玉米品种高产高效栽培生理研究和抗逆玉米新品种选育提供理论指导。     

青贮玉米品种试验的问题及对策探讨

为青贮玉米品种的选择提供一定的参考,分析了青贮玉米品种试验存在区域布局、试点分布不合理,品种类型缺乏全面定位,育种水平不高等问题。指出青贮玉米品种未来的发展方向定位于粮饲兼用型是毋庸置疑的,但专用青贮玉米同样有其生存的空间。分析表明,应着力开展专用青贮玉米品种试验,合理布局,在条件成熟时可在普通玉米生产试验中发现青贮产量高的品种作为其特点予以关注。     

密植条件下玉米主要农艺性状的综合性分析

【目的】研究新疆北疆地区玉米品种密植条件下的株高、穗位高、穗长、穗粒数、穗粒重、脱粒含水量等主要农艺性状和产量的变化，找出该地区密植条件下玉米产量的主要因子，为筛选出适宜新疆北疆地区种植的耐密高产优质的玉米品种提供科学依据。【方法】采用北疆18个中熟玉米品种为材料，在10.5×10⁴株/hm²密度下，分析各参试玉米品种产量及主要农艺性状。【结果】在密植条件下各参试品种产量差异极显著；产量与行粒数(r=0.565^*)、百粒重(r=0.485^*)呈显著正相关；18个玉米品种的9个农艺性状可以解释85.6%的产量变异；优化后的线性回归方程为Y=-16.391+0.469X₆+0.33X₈。【结论】新疆北疆博州地区密植条件下选择玉米品种时，选择穗长稍长、穗粒重较大、百粒重较重且脱水快的品种，华西704,登海1707和华西917可作为新疆博州地区中熟春播地膜玉米栽培选择品种。     

环洞庭湖区平原湖区旱地夏季玉米品种比较研究

为了筛选适合洞庭湖区种植的优良玉米品种,2012年在湖南省安乡县平原湖区旱地进行了玉米品种比较试验。结果表明:豫玉22号和源玉16的产量较高,分别达9 518.66、9 351.90 kg/hm2,而且综合性状和田间表现较好,适宜在环洞庭湖平原湖区旱地地区推广应用。     

Trade and <Emphasis Type="Italic">Totomoxtle</Emphasis>: Livelihood strategies in the Totonacan region of Veracruz,Mexico

Following the implementation of the North American Free Trade Agreement (NAFTA), Mexican farmers altered their livelihood strategies to respond to changing market incentives. While many commercial farmers responded to falling maize prices brought on by NAFTA by shifting into the production of vegetables for export, the coping strategies of low-income farmers have been varied, from diversifying income sources through off-farm employment, to migration, to searching for niche markets for new or added-value products. In the Totonocan region of the state of Veracruz, Mexico, many farmers who can no longer earn sufficient income from the sale of maize grain are turning to a byproduct of maize to generate income. The commercialization of totomoxtle, or maize husks, for domestic and international markets has not only enabled farmers to continue to profit from maize production, but it has also encouraged farmers to utilize and conserve criollo maize varieties that serve as important reservoirs of genetic diversity. Moreover, the growing importance of totomoxtle in livelihood strategies has caused some farmers to alter their maize management, selecting for better quality husks rather than for grain production. The purpose of this paper is to understand both the broad impact of NAFTA on the local agricultural economy and its more specific effects on the management of maize in the Zona Totonaca. Participation in international trade can lead to unexpected outcomes, in some cases creating new values for goods with a long history of local consumption. Commercialization of maize husks is likely to be only a temporary solution for the relief of rural poverty. Given the volatility of international markets, the long-term welfare of farmers may depend on the development of more diversified production strategies. Amanda King Amanda King holds an MSc from the University of California-Berkeley in Environmental Science, Policy, and Management. She was a Mickey Leland International Hunger Fellow based at the International Center for Maize and Wheat Improvement (CIMMYT) in El Batán, Mexico in 2003 and at the International Food Policy Research Institute (IFPRI) in Washington DC in 2004. She is currently conducting research in East Kalimantan, Indonesia on oil palm plantations and changes in local livelihoods.