旱地棉花高产模型及优化途径研究

采用正交旋转回归设计,研究了影响旱地棉花产量构成的密度、肥料、DPC化控三项农艺措施之间的关系。结果表明,在旱地条件下,影响棉花产量的三项农艺措施顺序依次为密度>化控>肥料。此外还研究了三项农艺措施之间的互作效应,并建立了旱地棉花高产模型。最后分析了旱地棉花土壤水分利用率和经济效益。     

黑龙港生态区旱地棉田综合栽培措施优化组合的筛选

本试验研究了7项主要栽培因素对黑龙港生态区旱地棉田棉花的生育及产量的效应,建立了不同降水年型综合栽培措施与产量的回归方程,通过模拟寻优,筛选出了正常降雨年型产籽棉3000kg/(hm)~2,干旱年型产籽棉2625kg/(hm~2)和丰水年型产籽棉3450kg/(hm)~2水平下的优化措施组合,为该区旱地棉生产提供了科学依据。     

山东旱地棉花的生态特点和栽培技术

随着棉田种植制度的改革，山东省旱地棉花已发展成为重要的棉花生态类型之一。本文对旱地棉花的生态特点和生育特点进行了总结，提出了以蓄水保墒、增加密度、重施基肥、增施磷肥、提早追肥等措施为主的旱地棉花栽培技术。     

旱地与水浇地棉花生长发育特点比较研究

在大田条件下对旱地与水浇地棉花的生育特点进行比较研究。结果表明，干旱一般不影响棉花的生育进程，但显著抑制营养体的生长，并通过影响铃数、铃重和衣分而导致减产。旱地棉花的生物产量和经济产量因播种期早晚而呈现显著差异，旱地棉花播种期不宜晚于５月５日。     

我国旱地棉花生态区特点及农艺性状表现

研讨了我国旱地棉花生态区的生态特点、农艺性状及其变化规律。认为在诸多生态因素中,生育期降雨的季节性分布至关重要,由此而构成的受旱特点是区分旱地棉花生态区的重要依据,也是形成农艺性状变化规律最基本的因素。不同生态区的旱涝特点,是影响皮棉产量和农艺性状的主要矛盾,缓解这一矛盾或采取补偿措施是促进旱地棉花生产的基本方略。     

创造旱地种棉丰产纪录 周顺的经验介绍

在目前一般棉区棉花每亩平均产量只有一百斤左右(籽棉),旱地种棉最多也不过二三百斤的情况下,一九五○年河北省临清县周顺的四亩旱地棉花,平均每亩产到四七○斤(霜前花占到百分之九二·五),创造了早地种棉丰产的新纪录。周顺家住临清一区柳家坆村,是六十多岁的植     

旱地棉花“四水、一密、一防”栽培技术

旱地棉花“四水、一密、一防”栽培技术乔效克穆建立朱灵枝洛阳市位于河南省西部，气候属于半湿润易旱区和半湿润偏旱区，年降雨量５００毫米～６００毫米。长期以来，干旱一直是棉花生产的主要限制因素。当地群众在长期与旱灾作斗争中逐渐摸索一套旱地棉花“四水、一密、...     

陕西关中旱塬地区棉花缺苗问题的调查与研究

一、旱地棉花缺苗问题是阻碍单位面积产量提高的首要原因保证全苗是植棉获得高额丰产的第一个要求,无苗或严重缺苗就没有丰产的条件。过去几年来旱地棉田一般缺苗普遍而严重,妨碍了棉花单位面积产量的提高。据西北农业科学研     

丘陵地区不同缓释(控失)肥对棉花的影响研究

为选择适宜于丘陵地区棉花生产上应用的缓释(控失)肥品种,在怀宁丘陵地区旱地上进行了不同的缓释(控失)肥对棉花农艺性状、产量及施肥用工的影响试验。结果表明,丘陵旱地棉花施用不同的缓释(控失)肥,棉花的生育期略有延长,其株高、单株果枝数、单株结铃数、衣分以及籽皮产量都有不同程度的提高,但与对照的差异不显著,不同缓释(控失)肥之间差异也不显著;全程一次性施用缓释(控失)肥均可以替代常规分次施肥,节省施肥次数及用工。因此,不同的缓释(控失)肥在丘陵地区旱地棉花上施用是可行的,均可在生产上应用。     

FA旱地龙多功能棉用型滴灌肥在棉花上的应用试验

为了研究FA旱地龙多功能棉用型滴灌肥的增产作用，2007年我们通过大田小区试验和盆栽试验，研究其对棉花的根系发育以及产量的影响，为提高棉花单产提供科学依据。     

An economic evaluation of alternative pix application strategies for cotton production using GOSSYM/COMAX

The plant growth regulator pix (mepiquat chloride) is used extensively throughout the USA cotton belt to control excessive plant growth and to enhance early crop maturity in cotton production. Economic returns from pix use can vary greatly across different production environments. This study evaluates the economic returns to dryland cotton obtained from 12 different pix application strategies under two different soil types (Bosket sandy loam and Dundee silty clay loam) and three different weather conditions (normal, cold-wet, and hot-dry) in the Mississippi delta using simulated output from the GOSSYM/COMAX cotton management system. The most profitable pix application strategies varied by soil type. Also, economic returns were larger when using different pix application strategies for different weather conditions as opposed to using one pix application strategy for all weather conditions.     

气象因素对旱地棉花产量及农艺性状的影响

研究了气象因素对旱地棉花产量及农艺性状的影响。9年试验资料分析表明,各因素对产量和有关性状影响的大小,因生育时期而异。整个生育期间,干燥度和蒸发量是产量的主要决定因素,株铃数、铃重和绒长与其关系密切;苗期,蒸发量是主要决定因素,铃重与其关系密切;蕾期,降雨量是主要决定因素,铃重和株高与其关系密切;铃期,蒸发量和积温是主要决定因素,株铃数、绒长和生育期与其关系密切。其间,各因素对有关性状和产量的影响表现了较高的同步性。由此认为,这一规律可作为旱地棉田综合治理的重要依据。并提出了旱地棉花育种和栽培的有关方略。     

山西省旱地小麦育种进展与育种策略探讨

山西是北方麦区典型的干旱省份,旱地小麦面积比例较大,旱地小麦生产对全省小麦生产起着至关重要的作用。为了选育抗旱性、丰产性、稳产适应性等方面具有突破性的小麦品种,归纳了山西小麦生产发展概况,总结了山西旱地小麦育种在团队建设、育种方法、育种成果等方面的研究进展,分析了当前生产条件下旱地小麦育种存在的问题,指出应从育种目标、种质材料创新和育种方法等方面进行突破的育种策略和探讨建议。     

棉花生长发育模型及其在我国的研究和应用进展

棉花是一种重要的经济作物,棉花优质高产高效生产对于我国具有战略意义。棉花生长发育模拟模型从棉花的内部生理过程、外部形态结构及其与生长环境的动态交互出发,实现作物生长发育和产量品质形成过程的动态描述和精确模拟,为棉田生产管理措施的优化决策提供了极大的帮助和便利。本文在综合介绍棉花生理生态过程模型、棉花形态结构模型和棉花功能-结构模型的技术原理、组成结构和功能特点的基础上,深入探讨了棉花生长发育模拟模型在国内外研究进展,对棉花生长发育模型在我国棉花生长发育和产量形成、灌溉优化、施肥决策、病虫害管理及棉花生产区域系统评估方面的应用现状进行了系统介绍。根据我国棉花生产的实际情况,结合我国农业信息化发展方向,从模型的本地化研究、尺度提升及其推广示范方面为我国棉花生长发育模拟模型研究、发展和应用提出了建议,以期进一步推动我国棉花产业的现代化发展。     

Spatial variation of fiber quality and associated loan rate in a dryland cotton field

A field study was conducted in 2006 in a dryland cotton field in Texas, USA, to explore the spatial variation of cotton fiber quality and the loan rate associated with it. A total of 66 cotton samples were hand-harvested, and the fiber quality properties investigated included the High Volume Instrument measurements of micronaire, length, uniformity, strength, elongation, reflectance (Rd) and yellowness (+b). Conventional statistics showed a generally low level of variation in fiber quality with coefficients of variation <10%. Variogram analysis showed that all fiber quality properties were spatially correlated. Contour maps of individual fiber quality properties were produced from block kriged estimates. Fiber length, uniformity, strength and Rd were positively correlated, and all of these were negatively correlated with +b. The spatial distribution of most fiber quality properties was similar to that of soil apparent electrical conductivity, suggesting that water holding capacity could be a limiting factor for cotton fiber quality. Maps of individual fiber quality properties were combined with the United State Department of Agriculture—Commodity Credit Corporation Loan Schedule for Upland Cotton to create a loan rate map that is associated with fiber quality. A loan rate difference of 20 cents kg^–1 was observed within the field. This level of difference indicated that fiber quality at the field level can have a large impact on producers’ revenue. A site-specific management system encompassing both lint yields and fiber quality is strongly recommended for cotton production.     

我国旱区农业的地位和发展潜力及政策建议

我国旱区地域广阔,资源丰富,民族众多,是未来我国大西北的重要生态屏障区域,在我国的经济建设、社会稳定、国防安全和生态安全方面都具有重要的战略地位。以干旱缺水为核心的众多因素制约着旱区农业的持续发展,但同时特有的土地资源和气候条件也决定着该区农业生产具有巨大的潜力。实践证明,通过科技水平的提升,完全可以实现旱区农业经济的可持续发展。提出制定旱区农业发展和生态文明建设科技规划;设立旱区农业与生态协调发展专项;进一步发挥杨凌示范区作用,赋予统筹旱区农业科技资源的职责,加强协同创新的三项带有战略研究性质具体建议,探讨了未来旱区农业发展和结构调整的方向。     

Managing Uncertainty in Site-Specific Management: What is the Best Model?

Models which enable the representation of spatially variable crop performance are central to site-specific management. Rarely have these models been considered in relation to the different sources of uncertainty facing the decision maker. This paper describes various sources of uncertainty (temporal, metrical, structural, and translational) in the context of the site-specific management problem and the model types proposed to solve the problem. An example involving the site specific application of nitrogen fertilizer in dryland wheat production is presented to show how these model types might be evaluated for suitability to a given situation. We conclude that in data poor situations, knowledge-driven models may be less accurate but preferred by the farmer, while in data rich situations data-driven models may be more appropriate.