夏玉米增密后容易出现的问题及对策

依靠科技,主攻单产,大力推广玉米高产综合配套技术是发展玉米生产的主要途径.现在我国正在大力推广的"一增四改"高产栽培技术,其主要核心技术是:合理增加种植密度、改种耐密型品种、改套种为直播、改粗放用肥为配方施肥、改人工种植为机械化作业,由于其贴近生产实际,可操作性强,具备广适性、系统性、完整性等特点,在发挥玉米增产潜力、提高玉米单产方面效果明显.但在玉米高产生产实践中,在增加密度后,出现了倒伏、秃顶等问题,严重制约了玉米的增产.     

加快推广“一增四改”的玉米增产技术措施

为进一步提高玉米单产水平，满足国内不断增加的对玉米的需求，最近农业部提出加快推广玉米“一增四改”的生产措施，即合理增加种植密度，改种耐密型高产品种，改套种为平播，改粗施用肥为配方施肥，改人工种植为机械化作业，建立以合理密植为中心的玉米高产栽培技术体系。     

夏津县夏玉米高产高效栽培关键技术

<正>近年来夏津县夏玉米种植发展迅速,2015年种植面积突破4.4万hm~2,面积略低于小麦但产量高于小麦,是本县第一大粮食作物。根据本县气候、地力及种植习惯,夏玉米在"播种—管理—收获"生产环节因地制宜推广"精量直播晚收"、"一增四改"及"一防双减"等高产高效栽培关键技术,减少化肥农药用量,实现玉米优质高产高效,推动夏津县玉米健康发展。     

夏津县夏玉米高产高效栽培技术

近年来夏津县夏玉米种植发展迅速,2015年种植面积突破4.4万hm2,面积略低于小麦但产量高于小麦,是本县第一大粮食作物.根据本县气候、地力及种植习惯,夏玉米在“播种—管理—收获”生产环节因地制宜推广“精量直播晚收”、“一增四改”及“一防双减”等高产高效栽培关键技术,减少化肥农药用量,实现玉米优质高产高效,推动夏津县玉米健康发展.     

玉米“一增四改”高产栽培技术解读

“一增四改”是2012年黄淮地区玉米高产栽培的主推技术,即增加种植密度,改平展叶形品种为耐密型高产品种,改套种为直播,改粗放施肥为按叶龄指数配方施肥,改人工播种为机械播种。为加速推广该项技术,做到家喻户晓,群众乐于接受,本文就主推玉米“一增四改”技术的原因展开解读。     

以增加密度为核心,集成推广玉米高产创建技术体系

北京市在实施玉米高产创建活动中,根据实施目标和玉米生产上存在的主要技术问题,确定了以增密为核心的"一增二改三提高"技术方案,集成建立了新的玉米高产栽培技术体系,在示范区强化推广应用.两年共建立示范区7 114hm2,实现了单位面积产量的稳定跨越和总产增加,带动北京市玉米单产从全国中下水平上升至中上水平,为进一步提高玉米产量水平开避了一条新的技术途径.     

夏玉米“一增四改”高产栽培技术

玉米“一增四改”技术即：合理增加种植密度,改种耐密型品种,改套种为直播,改粗放用肥为配方施肥,改人工种植为机械化作业。通过近几年实施和推广,取得了良好的增产增收效果。加大玉米”一增四改”技术的推广应用,对进一步提高夏玉米产量水平,具有十分重要的意义。     

提高紧凑型玉米单产的几个技术环节

<正>阿克苏地区热量资源丰富,是新疆玉米的主要产区。2007年农业部提出"一增四改"重大技术措施,即合理增加种植密度,改种密植品种,改套种为平播,改粗放用肥为配方施肥,改人工种植为机械化作业。但是,目前本区生产上一直沿用传统的栽培方法,只注重品种选择,忽视栽培技术应用,导致良种良法不配套,     

实施密植高产机械化生产 实现玉米高产高效协同

为探索生产方式转变,实现玉米产量与效益协同提高,分析了玉米种植密度提高与单产增加的关系、不同产区玉米种植密度现状、增密种植的增产效果以及子粒机械直收技术的优势,构建了以筛选耐密抗倒适合机械化生产品种、密植增穗增产、提高群体整齐度、构建高质量群体、全程机械化作业、强化规模种植与统一管理、实施全成本核算为核心的玉米密植高产全程机械化生产技术模式。该模式2013年起被农业部遴选为全国玉米主推技术,在全国玉米主产区推广,创建了一批高产高效典型。其中,经农业部组织专家验收,2014年在新疆兵团71团创造了18 414kg/hm~2的全国玉米大面积高产纪录,净利润达到24 118.2元/hm~2,实现了玉米高产与高效协同,为玉米生产方式转变和发展现代玉米生产提供了典型案例。     

鲁西南地区夏玉米高产群体调控技术

<正>随着玉米一增四改技术措施的推广和高产创建活动的开展,鲁西南地区的玉米种植习惯也随之改变,夏玉米种植密度也显著增加。密度的增加要求相应的管     

植物新品种保护与品种审定的意义和异同

随着知识产权愈来愈受到社会各界的关注，植物新品种保护工作也显得尤为重要。该文着重介绍了植物新品种保护的发展概况、意义及其与品种审定的异同，使读者对植物新品种保护工作有所了解。     

大白菜施肥技巧与主要病虫害防治

1施肥技巧 大白菜施肥原则是：整地重施有机肥，苗后分次巧追肥。追肥要掌握“少量多次、前少后多、分期供给”。肥后及时浇水，以达到肥水均匀，充分发挥肥效。     

果蔬采后存在问题及贮藏保鲜技术发展

随着生活水平的提高,果蔬产品成为人们摄取营养元素的重要食品之一。分析了我国果蔬采后存在的问题,并对低温及气调保鲜、化学保鲜剂、涂膜保鲜技术及超声保鲜技术等贮藏保鲜技术研究进行了综述,指出我国果蔬贮藏保鲜技术持续、稳定、健康的发展要倚重于科技创新。     

Dry matter and nitrogen accumulation and residues of oil and protein crops

Oil and protein crops are of growing importance in cropping systems. This study was carried out to compare oil crops of linseed, rapeseed, sunflower and protein crops of faba bean and white lupin for grain production, residual plant dry matter and nitrogen. Two field experiments with either oil or protein crops were conducted in 1993 and 1994, respectively. Total dry matter production, grain yield, residues, N concentrations and mineral N in the soil were measured. Dry matter production and distribution as well as N uptake and residues varied greatly among species and between years. In 1993, oil crops gave up to 3 t ha⁻¹ grain and 16 t ha⁻¹ residues with sunflower, while in 1994 up to 5 and 11 t ha⁻¹, respectively, were recorded with winter rape. Protein crops showed an opposite reaction in years. Nitrogen uptake and residual N amounts were correlated with dry matter production. Plant residues of oil crops contained 20–140 kg N ha⁻¹; those of protein crops up to 80 kg N ha⁻¹. Despite the variation of residual plant N the variability of mineral N in the soil at harvest was hardly influenced by crops and amounted to only 20–50 kg NO⁻₃-N ha⁻¹.     

我国蔬菜产业和科学技术的发展与展望

1　我国蔬菜产业的发展现状蔬菜是人们日常生活中不可缺少的副食品,也是我国目前种植业中最具活力的经济作物。改革开放以来,随着市场经济的发展,农产品产销体制的不断改革和完善,特别是1988年实施“菜篮子工程”以来,蔬菜产业得到了蓬勃发展。1.1　播种面积1987~1999年,全国蔬菜播种面积由533.3万hm²,发展到1333.3万hm²,增长139.5%。1.2　总产量1987~1999年,全国蔬菜总产量由1.55亿t增加到4.05亿t,增长161.3%,使年人均鲜菜占有量达到330.7kg(世界各国人均105kg……     

向日葵抗盐碱生理生化机制与生长发育特性分析

以Y05-222A和Y06-136R杂交得到的135株F₂群体为研究材料,测定过氧化物酶（POD）、超氧化物歧化酶（SOD）、脯氨酸（Pro）、过氧化氢酶（CAT）、可溶性蛋白和丙二醛（MDA）等6个生理指标,并进行方差分析、相关性分析和通径分析,对F₂群体进行偏度及峰度分析。结果显示,以上6个生理指标在F₂群体中P>0.05,分布频率符合正态分布,同时存在双向超亲分离现象;相关性分析和通径分析显示,这些指标与抗盐碱系数均呈极显著相关（正相关或负相关）,且相关系数与总间接通径系数方向一致。POD活性的直接通径系数为0.5003,可见POD直接影响抗盐碱性;CAT活性和Pro含量的直接通径系数分别为-0.1317和-0.0384,间接影响抗盐碱性;SOD活性、MDA及可溶性蛋白含量直接或间接影响抗盐碱性。POD、SOD、Pro、CAT、可溶性蛋白和MDA各生理指标的抗盐碱作用表现为POD>CAT>Pro>可溶性蛋白>MDA>SOD。叶片数、株高、茎粗和盘径与抗盐碱系数呈极显著正相关,其相关性表现为叶片数>盘径>株高>茎粗。以上结果可为研究油用向日葵抗盐碱性提供一定的理论基础。     

果蔬食品的褐变与控制

结合生产实际,对果蔬食品产生褐变的机理及其控制途径进行探讨。通过遗传学途径,培育果蔬新品种,使之不含易氧化变色物质,增强其天然抗褐变性,是控制果蔬褐变的根本途径。     

On Fengshui and Rockery and Water Layout

Definition of Fengshui and the theories of selecting mountain and water environment in Fengshui were elaborated. Theories about mountain-water relationship were expounded from the perspective of piling of rockeries and layout of water, a residential area in Hefei City, Beijing Olympics Park, Hangzhou Prince Bay Park, mineral pit of Shanghai Chenshan Botanic Garden, Beijing Beihai Park, Shanghai Changfeng Park were taken for example to demonstrate the influence of traditional rockery and mountain layout in Fengshui on modern landscape design.     

Approaches and Applications of Chemomics and Chemoinformatics

Some novel concepts of chemomics/molomics are proposed including hydrocarbomics, alcophenomics, carboxomics, pepitomics, metabonomics, etc. like genomics, protomics and glycomics in bioomics. Some examples are given to demonstrate the chemomics and/or molomics methodology and technology based chemoinformatics and bioinformatics and their wide applications in Chemistry and Biology.     

Acidity and sweetness in apple and pear

Summary Sweetness and acidity in apple and pear inherit independently and can be organoleptically evaluated separately, but less accurately in pear than in apple. For breeding purposes an analysis of fruits for acidity and sweetness with pH indicator paper and a hand refractometer is to be prefered to the organoleptic method.In apple, the acidity-decreasing with time-of the unripe fruit was already strongly indicative of that of the eating-ripe fruit; sugar-increasing with time-not before the fruit was picking ripe. Sugar content in apple and pear, and the pH in pear, appeared to be normally distributed; the pH in apple showed a segregation into an acid and a low-acid group, which occurred in both the unripe and ripe stage. The segregation ratio between these groups was found to be highly variable. On the whole, the mean acidity and sugar content of apple and pear progenies is significantly determined by that of the parents. Most of the observations made did not support the theory that low acidity in apple is determined by one recessive gene. The relationship between the pH of leaf juice and fruit juice in apple may offer a possibility for pre-selection.