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采用正交设计方法，研究不同生态条件下不同玉米组合、不同行窝距、不同带距玉米群体结构主要质量指标与产量关系。结果表明：在高、中海拔区，贵毕３０３以每６６７ｍ２种植密度３４００～４４００株，贵毕３０１３５００～３８００株，黔西４号３０００～３６００株，毕单３号３０００～３３００株的群体结构较合理，其叶面积系数、干物质积累量、光合势、净同化率、总粒数等主要质量指标都比较理想，产量也高。同一玉米组合，叶面积系数、总粒数高海拔区较中海拔区大；群体干物质生产量高海拔区比中海拔区高１１．８８％～６９．０８％，但干物质向穗中转化率则是高海拔区（４６．３５％）小于中海拔区（５２．０３％） 相似文献
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通过对不同生态条件下王米主要生育阶段田间小气候的观测分析，结果表明，毕节高海拔地区３３３３～４４４４株／６６７ｍ２，在玉米生长发育关键时期（大喇叭口—抽雄吐丝）的田间小气候随密度增加更为适合玉米生长发育及产量形成，特别是每６６７ｍ２４４４４株这一密度群体结构最为合理，株间温度２２～３３℃，相对湿度为８５％左右，对太阳辐射能吸收能力强，反射损失少，气候资源的利用率较高，玉米实际６６７ｍ２产５２２．３ｋｇ，马铃薯、玉米套作复合产量达６７６．５８ｋｇ／６ｍ２，相对于其它密度能获得较佳的生态环境和经济效益。若按当地当年气候资源估算，其利用率仅为３４．８％，可能增产潜力非常大。 相似文献
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辽西地区不同种植模式对春玉米产量形成及其生长发育特性的影响 总被引：12，自引：0，他引：12
改变玉米田间种植模式是提高玉米单产的重要措施之一。本文在大田试验条件下, 以耐密品种(郑单958)和中密品种(沈玉21)研究了三比空密疏密、大垄双行和等行距(CK) 3种种植模式对春玉米产量形成及其生长发育特征的影响。结果表明, 田间种植形式的改变可以显著影响玉米群体产量及其生长发育特征。耐密品种以大垄双行种植模式为宜, 可以增加玉米的株高、茎粗, 提高叶面积和光能利用率, 促进干物质积累, 两年平均产量为8882.36 kg hm-2, 比对照增加6.51%, 增产的原因是百粒重和穗行数的显著提高; 中密品种以大垄双行和三比空种植模式为宜, 两种种植模式均可增加玉米的株高、茎粗, 提高叶面积和光能利用率, 促进干物质积累, 且与耐密品种表现不同, 两年平均产量分别为8294.58 kg hm-2和8188.30 kg hm-2, 比对照增加21.36%和19.81%, 增产的原因是行粒数的显著增加。因此, 笔者认为在辽西地区特定的自然条件下大垄双行是提高玉米单产的最佳种植模式。 相似文献
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种植密度对小麦群体光能资源利用的调控效应 总被引：3，自引：0，他引：3
为提高小麦光能利用率和产量本试验于大田条件下,研究了种植密度对冬小麦品种石新828群体光能资源利用的调控效应.设置4个密度水平处理(210×104基本苗/hm2(D1)、270×104基本苗/hm2(D2)、330×104基本苗/hm2(D3)和390×104基本苗/hm2(D4)).试验结果表明,种植密度对小麦石新828群体光能利用具有显著的调控效应.D3处理的小麦群体合理,叶面积指数适宜,群体受光态势良好,且小麦群体的消光系数和生物量光能利用率均在生育后期表现出明显优势,最终使得小麦籽粒光能利用率及产量显著高于其他处理.D1和D2处理的群体透光率和净同化率在整个生育期均表现出明显优势,但由于小麦群体相对较小,农田漏光严重,干物质积累量显著低于其他处理;D4处理的群体叶面积指数和光合势在整个生育期均显著高于其他各处理,但由于群体相对较大,群体基部透光率较小,小麦群体的净同化率、消光系数和生物量光能利用率在生育后期表现出明显的劣势;最终均导致了小麦籽粒光能利用率和产量的降低.由此表明,在本试验条件下,适宜的种植密度使群体具有良好的受光结构和持久的光合同化能力,得到适宜的干物质积累量,协调营养物质向籽粒中转运,最终使小麦籽粒光能利用率高达0.572%. 相似文献
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本文根据1988～1986年的试验资料,分析了不同种植密度和种植方式对蚕豆产量、有关生理指标、群体结构及光能分布的影响。证明在安宁河流域太粒型蚕豆播种的最适密度为亩基本亩15000～18750株,该群体结构较亩基本亩8333株的增产30%以上。宽窄行种植比等行种植增产10～40%,以33厘米和20厘米的宽窄行效果最好。最适种植密度和宽窄行播种增产的原因是提高了蚕豆中后期叶面积指数,增大光合势和净同化率,使群体光能分布均匀,改良收获指数,提高了光能利用率。本文还利用大田切片法对不同种植密度和不同种植方式蚕豆群体结构和光能分布进行了比较. 近年来,国内外对蚕豆种植密度和种植方式作了一些研究,但不同地区差异极大,Pandey等试验证明蚕豆田由11.1株/平方米增至133.2株/平方米,生物产量和经济产量几乎成直线增加。上海农学院试验发现超过15株/早方米产量下降。在种植方式方面,张成昌等提出,蚕豆以宽窄行种植比等行种植增产15.9～39.3%;上海农学院试验认为以宽行窄株距条点播为好。可见,最佳密度和方式受地区和品种影响极大。地处西南高原的安宁河流域,有成片种植蚕豆并以收获籽粒为种植目的的历史,但历年来产量徘徊在亩产75公斤左右,低产原因之一是种植密度和方式不合理,因而寻求适合本地最佳种植方式和密度,是生产上需要解决的问题之一。本文根据1983～1986年三年的试验资料,分析了不同密度和方式对蚕豆产量、有关生理指标、群体结构及光能分布的影响。 相似文献
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玉米空秆秃尖的原因及防治方法 总被引：2，自引：1，他引：1
1玉米空秆发生的原因
1．1在玉米种植过程中，耐密性差或平展型的品种要稀植，耐密性强或竖叶型的品种要密植，耐密性强的品种适宜密度范围广，在一定范围内呈现密度增加产量上升趋势但密度过大时则空秆率增加，产量降低。平展型玉米因适宜的叶面积指数小于紧凑型玉米，在密度过大时群体内光照条件恶化， 相似文献
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玉米不同株型品种的高产潜力及群体光合特性研究 总被引：4，自引：0，他引：4
选用高产潜力大的株型品种,建立相应的群体结构,提高群体光能利用率,发挥株型品种的最大生产潜力,是玉米高产栽培中亟待解决的问题。近年来,国内外不断推出株型不同的玉米良种,并在生产上发挥了巨大作用,但有关株型品种的高产潜力及群体光合特性研究尚少。现将这方面研究结果介绍如下:…… 相似文献
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玉米群体光分布特征及其对产量和品质的影响 总被引：18，自引：2，他引：16
通过测定不同种植密度玉米群体的光能分布,研究了群体光能分布特征对玉米产量和品质的影响,结果显示,只有光照条件适宜的群体,才能充分利用光能,并可获得高产优质的玉米子粒。 相似文献
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1 症状1.1 缺氮 :幼苗矮化 ,瘦弱 ,叶丛黄绿。生长株从叶尖开始变黄 ,沿叶片中脉发展 ,叶片上形成一个“V”形黄化部分 ,致全株黄化 ,后下部叶尖枯死且边缘呈黄绿色。缺氮严重或关键期缺氮 ,果穗小 ,顶部籽粒不充实 ,蛋白质含量低。1.2 缺磷 :嫩株敏感 ,植株矮化 ,叶尖、叶缘失绿呈紫红色 ,后叶端枯死或变成暗紫褐色。根系发达 ,雌穗受粉受阻 ,籽粒不充实 ,果穗少或歪曲。1.3 缺钾 :下部叶片的叶尖、叶缘呈黄色或似火红焦枯 ,后期植株易倒状 ,果穗小 ,顶部发育不良。1.4 缺钙 :植株矮 ,新叶生长受阻 ,新叶尖端几乎完全失绿 ,分泌透明… 相似文献
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Vegetable oils are a high-value agricultural commodity for use in refined edible oil products and as renewable industrial or fuel oils, and as the world population increases demand for high-quality seed oils continues to grow. Worldwide the oilseed market is dominated by soybean (Glycine max), followed by oilseed rape/canola (Brassica napus). In Europe the major oilseed crop is oilseed rape (B. napus), followed some way behind by sunflower (Helianthus annuus) and other minor crops like linseed (Linum usitatissimum) or camelina (Camelina sativa). The seed oil of these crops is characterized by a specific quality, i.e. fatty acid composition and other fat-soluble compounds: Camelina and linseed oils are characterised by high contents of linolenic acid (C18:3); in sunflower very high-oleic (up to 90% C18:1) types exist in addition to classical high-linoleic (C18:2) oilseeds; in B. napus a broad diversity of oil-types is available in addition to the modern 00 (canola) type, e.g. high-erucic acid rapeseed or high-oleic and low-linolenic cultivars. Moreover, vegetable oils contain valuable minor compounds such as tocopherols (vitamin E). Increases of such contents by breeding have lead to value-added edible oils. After oil extraction, oilseed meals—such as rapeseed extraction meal—contain a high-quality protein that can be used as a valuable animal feed. However, in comparison to soybean the meal from oilseed rape also contains relatively high amounts of anti-nutritive fibre compounds, phenolic acids, phytate and glucosinolates. Breeding efforts with respect to meal quality are therefore aimed at reduction of anti-nutritive components, while increasing the oil content, quality and yield also remains a major aim in oilseed rape breeding. This review article provides a general overview of the status of oilseed production in Europe and uses examples from winter oilseed rape to illustrate key breeding aims for sustainable and high-yielding production of high-quality vegetable oil. Emphasis is placed on analytical tools for high-throughput selection of overall seed quality. 相似文献
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Summary The identification of environments suitable for selection should enable plant breeders to test reliably a larger number of genotypes with given resources. This research was undertaken to evaluate discrimination ability (DA) and prediction ability (PA) of eight environments involving two locations. Eckartsweier (Eck) 1 and Voelkenrode (Voe); 2 yer. 1984 (84) and 1985 (85); and two harvests, silage harvest (I) and later (II). It was based on dry matter yield of plant (PDMY), ear (EDMY) and stover (SDMY) and on in vitro digestible organic matter (IVDOM), neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL) of stover of 12 inbred lines and their 66 diallel crosses in maize (Zea mays L.). Linear regression coefficient of the performance of genotypes in an environment on that averaged across all environments and its degree of determination were used as measures of the DA and PA of environments, respectively. In hybrids, the DA of environments differed significantly for all traits except SDMY and ADL. Environment Eck851 showed better PA (0.63) than other environments for PDMY, EDMY, IVDOM, NDF, and ADF. Among the 12 two-environment combinations. EckI was a better predictor for PDMY, EDMY, IVDOM and NDF (PA0.80). The more productive environments showed better DA and PA for PDMY and FDMY than less productive ones. For IVDOM and NDF the first harvest provided better discrimination and prediction than the second harvest. In inbred lines the DA of environments differed significantly for EDMY only. In the present study, PA and DA seemed to be functions of the environments, PA was improved by combining two environments, and some environments seemed to be suitable for preliminary selection of genotypes for such diverse traits as yield and digestibility. 相似文献
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In the ironmaking process, it is essential that sinter and feed of blast furnace are established economically and reasonably. Taking some steel company for example, the best economical condition for feed of blast furnace is comprehensively considered from technologic demand and economic efficiency. According to LP and based on practice and trial, aimed function and confined condition is confirmed, computation programs are made by Matlab while realizing optimization feed. The blast furnace material balance and heat balance are calculated by program with visual interface. Thus, we can directly judge rationality of optimization. The results show that LP is effective method to realize feed of blast furnace. 相似文献
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矮秆小粒为栽培稻中一种特殊形态类型,表现为植株矮壮、叶片宽短、穗子粗短、谷粒短小但着粒特密,株高和千粒重为半矮秆正常类型的一半左右,矮秆小粒与半矮秆的原品种的杂种F2只分离出矮秆小粒与半矮秆两种类型,且符合1∶3的比例,这说明矮秆小粒类型是受一对隐性基因控制的多效性状,或者说由于一对隐性基因的作用导致了矮秆小粒这种形态类型.矮秆小粒材料Tax与12份(非原品种)半矮秆杂种F1代的株高、千粒重、粒长、剑叶长和宽等形态性状表现出显著到极显著(p=0.01～0.05)的超高亲,F2代同样表现出显著的超高亲分离,由此判定:矮秆小粒类型是由矮秆小粒材料遗传背景中的形态抑制隐性基因对半矮秆正常形态多效性隐性抑制的结果而不是矮秆小粒基因直接作用的结果,其作用方式是使其遗传背景中的半矮秆正常形态受到横向延展和纵向压缩从而变成粗壮矮缩的特殊形态类型.这与以往的研究结果不同,用该机理能很好地解释其它矮秆小粒材料研究中出现的类似异常遗传表现.矮秆小粒材料的育种利用价值和方法包括从中发掘利用大粒、优质和高产基因与创造以矮秆小粒类型为亲本之一的杂交稻超高产育种新途径. 相似文献
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繁种水稻采用机插技术 ,可以避免因人工紧张而耽误繁种水稻播种时间 ,影响产量。一般选择机械流水线作业加田间双膜育秧比较经济实用 ,操作也很方便 ,很容易掌握。1 种子准备及处理根据繁种水稻机插后群体发育和产量形成特点 ,选择大穗型或穗粒并重型品种作为机插繁种对象比较适宜 ,注意繁种稻生育期要适宜 ,确保安全抽穗。基础种要籽粒饱满 ,发芽率和发芽势强。基础种一般每亩大田需备足 5 kg左右 ,选择晴朗天气扬晒 1～ 2 d后用机械清选 ,去除枝梗、杂质、瘪粒 ,再用比重 1.1的盐水或黄泥水 (即用 5 0 kg水加盐 10 kg或黄泥 2 0 kg)选种 … 相似文献
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Improving white clover drought tolerance by selecting for more developed roots is controversial, labour‐consuming and complicated by the adventitious root system. This study aimed at assessing: (i) the value of thicker stolons as an indirect selection criterion for increasing root development, (ii) the relationship between root development and drought tolerance, and (iii) the consistency of population response for root and shoot traits between swards derived from seedlings or stolon cuttings. Thick‐ and thin‐stolon populations obtained by one cycle of divergent phenotypic selection within one ladino landrace, and one ladino natural population, were evaluated in metal containers (0.55 m × 0.12 m × 0.75 m deep) in a 1‐year experiment including vegetative material (seedling or stolon cutting) and drought stress (absent or present) as additional factors. Aerial dry weight (DW) was also assessed across two summer harvests under irrigated and rainfed field conditions for the thick‐stolon selection, two breeding populations selected from the same landrace regardless of stolon thickness, and the drought‐tolerant ladino ‘Brown Loam Synthetic no. 2’. The thick‐stolon selection had greater root DW (+21 %) than the thin‐stolon selection besides thicker stolons (+23 %). The natural population combined thinnest stolons with lowest root DW. Differences between populations were consistent across vegetative material. Primary and adventitious root systems did not differ for root DW in deeper soil horizons (>23 cm), above‐ground biomass and its reduction due to drought stress. Root DW increased under stress, particularly in deeper horizons. Aerial DW variation among populations evened up or narrowed much under stress, with no cross‐over interaction leading to an advantage of thick‐stolon material or ‘Brown‐Loam Synthetic no. 2’. 相似文献
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稻米食味品质检测评价技术的研究现状及展望 总被引：4，自引：1，他引：3
稻米的食味品质是稻米品质的重要组成部分,直接反映了稻谷的最终品质,因此稻米食味品质的检测与评价一直是研究的热点与重点。本文综述了稻米食味品质检测评价技术的研究现状和新检测评价技术的进展,总结了现有检测技术存在的一些问题,同时展望了基于电子鼻对稻米香味特性和食味品质检测的发展前景。 相似文献
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获得足够数量和高质量的RNA和DNA是进行分子生物学研究工作的基础。以小麦根腐离蠕孢菌为原料,分别采用溶菌酶法和液氮研磨法破碎真菌细胞壁提取DNA,用琼脂糖凝胶电泳、紫外吸收及聚合酶链式反应（PCR）技术进行核酸完整性和纯度检测。结果表明：两种方法在提取DNA时都同时得到了高质量的RNA;PCR检测结果表明DNA完整性比较高,两种方法得到的DNA质量相当;溶菌酶法中得到的RNA质量优于液氮法。利用溶菌酶破壁法提取小麦根腐离蠕孢菌DNA的提取体系可用于RNA的提取,为小麦根腐离蠕孢菌核酸的DNA和RNA的同时提取提供了一种简便、安全、可行的方法。 相似文献