选用性状比较典型的8个玉米杂交种，通过两年的比较试验，探讨黄淮海平原地区夏玉米高产栽培的品种特性。结果表明，在高产栽培条件下，不同玉米杂交种的生产力存在很大差别。在黄淮海平原地区，中大穗玉米杂交种的群体生产力表现出明显的优势，早期能够迅速建成合理的群体，具有较大的叶面积和光合势；后期叶片不早衰，光合生产能力强，干物质积累多，吐丝后干物质积累占的比例较大，分配合理，经济产量高。[著者文摘] | The results of high-yielding cultivation during two years showed that there were different productivities among different maize varieties in the high-yield cultivation conditions. In the Huang-Huai-Hai Plain area, the bigger ear maize varieties productivity of group was advantageous. They could quickly build reasonable group with their bigger LAI and LAD, they have higher photosynthesis than others because their leaves declined slowly after silking. They accumulated bigger dry-matter, the dry-matter after silking was bigger than before, so the yield was high.

基于现有的研究基础，对产量性能定量分析体系、产量层次差异和生产障碍进行了综合分析，进一步完善玉米高产分析的理论，明确挖掘玉米高产潜力的技术途径。①基于对三合模式的产量分析，提出了产量性能定量分析体系，根据玉米高产实例提出了超15000kg／hm. 的产量性能定量指标和进一步高产挖潜主攻方向；②明确了我国3大玉米主产区在光温生产、高产纪录、品种区试、农民生产田产量之间的产量层次性差异，分析了可能的原因和缩小产量层次差异的技术途径；③分析了我国目前不同玉米生产区的关键障碍性因素对产量性能可能产生的效应，提出了主要高产的技术保障措施，为实现我国玉米大面积高产高效目标提供理论与技术参考。[著者文摘] | In order to further improve the theory of high-yield analysis and understand technical approaches of yield potential in maize, the quantitative analysis system of yield performance, the differences in yield levels and the production obstacles were analyzed in this paper. Based on a quantitative analysis system of yield performance with ＂three combination structure＂, the quantitative indicators of yield performance were more than 15 000 kg/ha, and main directions of yield potential increase were raised according to maize high-yield example. Yield level differences in the three main producing areas of maize among thermal yield, maximum yield, yield in experimental area and yield in farm were analyzed. Technical approaches were suggested to narrow the differences in yield level. Key obstacle factor effects on yield performance were analyzed. In conclusion, these analyses were important to the goals of maize high-yield and high efficiency in China.

对湖南省稻米区域的比较优势、成本优势、质量优势、品牌优势、技术优势进行分析，结果显示，湖南省稻谷生产具有较强的区域比较优势、质量优势和品牌优势，技术优势和成本优势不明显，未能形成湖南稻米产业应有的整体优势。认为提升湖南省稻米产业竞争力的对策有：依靠科技进步提高稻米品质，提高稻米生产的综合效益，实施产品质量战略，建立龙头企业与农户多种形式的风险共担机制，发展稻米精深加工。[著者文摘] | The paper analysised on the regional comparative advantages, cost advantages, quality advantages, brand and technology advantages of Hunan rice by using theoretical and empirical methods. The rice production in Hunan had strong regional comparative advantage, quality advantage and brand advatage, no obvious technology advantage and cost advantage. And the paper discussed the feasible countermeasure of enhancing Hunan rice industry, which included improving rice quality by scientific and technological progres,enhancing overall efficiency of rice production, implement strategy of product quality, establishing risk-sharing mechanisms of enterprises and farmers, developing rice intensive processing.

玉米苗期低温会降低玉米对磷养分吸收能力，导致后期减产。改进玉米磷肥施肥方法将会提高玉米的产量。通过对玉米品种郑单958磷肥5种不同施肥方法的比较研究，表明种肥条施能促进玉米对磷的吸收，进而增加产量。促根剂促进玉米根系生长，增加了对磷吸收和产量的提高。[著者文摘] | Low soil temperature reduces absorbing capability for P in maize variety and later results in lower yield, during maize nursery in Jilin province. So development of applications of phosphorus fertilizers will raising maize varieties yields. This study was to compare with 5 application methods of P treatments in maize varity Zhengdan958. The results show that P row replacement treatment improves more yield and P uptake, bioeffector improve the root growth and inhance the yield and P uptake.

以农大108、四单19、龙单26、丰禾10和东农250为材料，在施氮（N. _┖筒皇┑_N0）两种条件下对参试品种的干物质、产量和品质性状变化进行了分析。结果表明：与氮胁迫相比，施氮能明显提高玉米干物质生产量、子粒产量、子粒粗蛋白含量和淀粉含量，但品种间存在明显的差异。农大108和四单19干物质积累能力强，但农大108没有表现出产量优势。[著者文摘] | Nitrogen is a large necessary element in maize development, and the nitrogen is an important factor in deciding the yield and quality of maize production. The purpose of this study was to analyze dry matter, yield and quality changes of character in five spring maize （Zea mays L.） cultivars, Nongdal08, Sidanl9, Longdan26, Fenghe10 and Dongnong250 under N input （N. __and N stress （NO） conditions. The results showed that with N0, N. _can significantly improved the dry matter production of maize, grain yield, grain and crude protein content of starch content, but significant differences existed between different varieties. Nongda108 and Sidan19 had a stronger ability to accumulate dry matter, but Nongda108 showed no yield advantage.

以15个辽宁省有代表性的中熟、中晚熟、晚熟玉米品种为试材，结合1999～2007年辽宁省玉米区域试验结果，对不同熟期品种的产量和生产性能进行比较研究。结果表明：中熟、中晚熟品种较晚熟品种有增产趋势，一些品种表现特别突出；中熟、中晚熟品种密植增产潜力大，密度适应范围广，稳产性更好；群体结构合理，经济系数高，源、流、库协调；在精量播种和机械化收获等方面，中熟、中晚熟品种有明显优势。[著者文摘] | The fifteen maize varieties which representative mid-maturing, mid-late-maturing and late-maturing in Liaoning province were carried, combined with the results of regional tests in Liaoning province during 1999 - 2007 and compared the yield and yield performance among different ripening period varieties, especially mid-matur- ing and mid-late-maturing maize varieties. The result indicated that the mid-maturing,mid-late-maturing varieties had yield-increasing tendency compared to late-maturing maize varieties. Some of the varieties had prominent performance. The mid-maturing, mid-late-maturing varieties had great close planting potential and broad density adapta tion scope and stable yield productivity. The mid-maturing, mid-late-maturing varieties had reasonable community structure and high harvest index and coordinated source-flow-sink relationship. They also had obvious superiority in accurate farming and mechanized harvest.

比较了春玉米和夏玉米在产量和品质、干物质积累、光温气候资源的利用等方面的差异。结果表明：春玉米比夏玉米平均增产1600kg/hm. ,前者的子粒粗蛋白含量也显著高于后者。春玉米的高生产力主要体现在干物质积累速率上，平均比夏玉米高15．8％，但年际间有一定的变异。春玉米对光温资源的占用率较高，但在光能利用率上并无明显优势。春玉米较高的产量潜力主要得益于营养生长期优越的光温条件以及较长的灌浆期；夏玉米灌浆期气候较适宦，但由于受冬小麦生育期的限制，产量潜力未得到充分发挥。[著者文摘] | A filed experiment was conducted to compare spring maize and summer maize regarding grain yield, grain quality, dry matter accumulation, utilization of solar, heat resources. The results indicated grain yield of spring maize was 1600 kg/ha higher than summer maize on the average. And spring maize had a significant higher grain quality than summer maize. Besides, the former one had obvious advantages on dry matter accumulation rate, which was 15.8% higher than the later one. The higher grain yield potential of spring maize benefited from superior solar condition during vegetative period and its longer grain filling duration. Climate condition during summer maize grain filling period was more favorable, while its grain yield potential had not been exerted fully due to limitation of winter wheat growing season.

【目的】探究蕉农对香蕉保险的支付意愿和支付能力,为政府优化香蕉保险制度设计提供决策依据。【方法】基于海南省1167户蕉农的实地调查,分别运用Logistic和CVM模型对影响蕉农参加香蕉保险意愿的微观影响因素和支付能力测度进行实证研究。【结果】影响蕉农参加香蕉保险的重要因子包括种植年限、身份、受教育程度、种植品种、2007年香蕉种植损失对家庭生产生活的影响程度、香蕉种植收入占家庭总收入的比重、是否试点区;蕉农平均意愿保费费率为0.14,蕉农平均意愿支付保费的能力为39%,蕉农希望政府补贴水平应达到60%。【结论】加大财政对农业保险的支持力度、深度和广度;积极开展农业保险产品创新,增加农业保险的有效供给;积极推进香蕉生产的规模化、专业化;启动农业保险发展的规划。 | [ Objective ] This article researches on the banana planters＇ willingness and capability of paying banana insurance, and provides the decision making basis for the government to optimize the system design of banana insurance. [ Method ] Based on the field survey of 1 167 banana planters in Hainan province, this article uses the Logistic and CVM model, and empirically studies the micro-affecting factors of banana planters＇ willingness and the estimation of ability to pay the banana insurance. [Result] The important factors that influence the banana planters to pay the banana insurance including： planting life, identity, level of education, varieties of banana, the influence level of the loss of the banana planting to the families＇ production and living, the proportion of the banana planting income in families＇ total income, whether it is a pilot area; the banana planters＇ average willingness premium rate is 0.14, the banana planters＇ capability of paying the insurance is 39%. Besides, banana planters hope that the government gives them subsidies of 60% of the premium. [ Conclusion ] The finance should enlarge the support intensity, depth and wideness of agricultural insurance; the agricultural insurance production should be positively innovated and the effective supply should be increased; the banana production should be scale and specialized; the development plan of the agricultural insurance should be started.

美国是世界上最大的玉米生产国,种植面积、总产和单产均居世界首位。转基因玉米自1996年引入生产以来,使玉米生产上了一个新台阶。当前推广利用的转基因玉米品种基本上是抗虫和抗除草剂两种类型。抗虫是由在玉米体内表达Bacillus Thuringiensis（Bt）毒素结晶蛋白（cry蛋白）基因所致,除草剂的抗性（Herbicide tolerance,HT）是由外源的或改良的EPSPS基因在玉米体内表达来实现。转基因玉米的种植面积每年都稳步上升,转基因玉米的也由单一的Bt或HT转变为多基因多性状的叠加,将抗玉米螟和抗Rootworm结合,使玉米的地上部和地下部都得到了有效的保护,再加之抗除草剂基因的叠加,使得转基因品种在生产上更具竞争力。转基因玉米的抗虫和抗除草剂等优良性状带来了巨大的经济和环境效益,并被越来越多的大众所接受。转基因玉米在短短10年间的应用和发展,还不能回答转基因作物对人类和环境的长期影响等问题。因此,对转基因作物的管理和利用仍不能掉以轻心,不能因对生物技术的热情而对人类和环境造成无意的不可挽回的破坏。[著者文摘] | The United States is the number one country in the world in terms of total corn acreage, total corn production and unit yield. Corn yields have been further improved by the introduction of transgenic corn varieties since 1996. The two major transgenic corns are insect-resistant and herbicide-resistant corns. Insect resistance was achieved by expressing in corn cry genes from Bacillus Thuringiensis（Bt） and herbicide tolerance by expressing either modified EPSPS or EPSPS from agrobacterium strain CP4. In the past ten years, transgenic corn acreage has grown steadily, and transgenic corn varieties have been improved from single transgenic traits to double and multiple traits stacked together. Transgenic corn has been proven successful in fighting insects, reducing pesticide application and increasing yield. However, issues about genetically modified organisms＇ long term effects on human health and environment still remain, and more research and studies are still needed.

利用作物生长分析法，研究了不同粒型玉米品种产量、产量构成和群体库源特征等指标与种植密度的关系。结果表明，种植密度为30000～60000株／hm. ，鲁单981（LD981）的单位面积实收穗数是决定群体子粒产量的限制因素；高于60000株，hm. ，穗粒数与千粒重则是决定群体子粒产量的限制因素。泉兴2101（QX2101）群体子粒产量的限制因素是单位面积实收穗数。LD981的单株产量、群体产量与产量构成因素对种植密度的敏感度要高于Qx210l，前者在较低密度时，易获得较高的群体库源比值与群体叶面积指数，产量潜力较高；后者则在较高密度时，易获得较高的群体库源比值与群体叶面积指数，产量潜力较高。群体库容量与源供应能力均是两种粒重类型玉米品种产量的限制因素，但群体库容量始终占主导作用。[著者文摘] | The relationships between planting density and yield, yield components, and population sink-source were studied synthetically by means of crop growth analysis method. The results showed that the ears numbers per ha were the main contribution factor to yield of LD981 when the plant densities of the maize were from 30 000 - 60 000 plant/ha, while the plant densities of the maize were more than 60 000 plant/ha, the kernels numbers per ear and 1000-kernels weight were the main contribution factor. However, the ears numbers per ha were all along the main contribution factor to yield of QX2101. The variety of planting density affected the single plant yield, the population yield and the yield components of LD981 were more than QX2101. LD981 gained easily biggish population sink-source ratio, canopy LAI and population yield when the plant densities of the maize were from 30 000 - 60 000 plant/hm. , while QX2101 gained easily biggish population sink-source ratio, canopy LAI and population yield when the plant densities of the maize were from 60 000 - 90 000 plant/ha. The sink capacity and source supply ability were contribution factors to yield of two kernels types maize, then the sink capacity was all along the pivotal factor.