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1影响玉米制种结实率的原因 1.1玉米制种田母、父本花期 花期相遇与否是决定玉米制种结实率的主要原因.花期相遇良好,母本种穗结实多,单穗产量就高;如果制种田父本超前或迟后,造成花期不遇,就会造成群体或个体果穗结实率低,制种产量低. 相似文献
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春玉米区玉米制种预防高温危害的方法与措施 总被引：2，自引：0，他引：2
2015年,春玉米制种区遭遇了高温危害,致使玉米制种授粉结实不良,造成减产,对国内玉米种子市场供给也造成巨大影响.高温危害,一是发生在7月20日即“入伏”前后10d左右,气温超过39℃将会影响玉米花粉的活力,会使玉米制种母本结实率降低,造成减产,甚至绝收;二是发生在入秋后的10d左右时段的“秋老虎”,这时的高温不会影响玉米制种授粉,一般也不会造成玉米制种田绝收.预防高温危害措施和方法,一是采取合理的栽培措施躲避或降低高温危害,如适时早播躲避高温,培育壮苗抗高温,调节好花期提高母本结实几率等管理手段;二是通过育种手段提高自交系的耐高温能力;三是运用综合措施,防患未然,事半功倍. 相似文献
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河西地区位于甘肃省西部,是典型的大陆性气候,年平均气温7~8℃,降水量60—610mm,蒸发量1400～3010mm,日照时数2200-3030h,无霜期85～165d。其生产的种子子粒饱满,光泽度好,千粒重高,商品性优。目前已是全国最大的玉米种子生产基地之一,常年制种面积达6万～7万hm2,年产种子占全国玉米用种量的45％以上。近年来,由于气候异常,玉米制种花期常遭受高温干旱、阴雨等不良气候的影响,造成空秆、缺粒、秃顶,致使产量下降、质量变劣,制约玉米制种产业的发展。如何改善玉米制种的胁迫条件,提高结实率,确保制种效益和质量,应成为河西地区玉米制种高度关注的问题。 相似文献
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一、问题的提出笔者分析了近几年所调查的198块不同类型制种田情况,其苗穗结构、结实率、制种产量等的相互关系是:有效穗与制种产量达极显著正相关(r=0.9144);结实率与制种产量达极显著正相关(r=0.8879);在相同有效穗(母本亩18万左右)结实率 相似文献
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玉米制种在玉米产业链中是承上启下且不可替代的一环,其自身的高效益对玉米产业发展有着巨大促进作用。2023年玉米品种NK815在新疆伊犁高产田制种产量达到1034.62kg/667m2,这是继2020年在甘肃张掖获得了877.44kg/667m2高产纪录后的又一新突破。这一“高质、高产、高效”玉米制种田的模式创建主要采取地膜覆盖、母本倒四叶展开去雄等农艺措施和技术,使其授粉期避开了当地7月份高温天气,保证了母本结实率,且在母本种植密度11693株/667m2条件下获得,为我国规模化高效益玉米制种树立了标杆和样板。通过进一步分析,提出了玉米制种高效益必须走高质高产、最大化挖掘利用好自然资源的新径;同时还提出了全产业链特别是有关杂交玉米制种父母本自交系抗低温、耐高温、耐贮藏、易加工等性状方面的选育育种目标。 相似文献
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随着玉米种植面积的增加,玉米苗枯病在我国玉米产区已普遍发生,在玉米制种田发病更加普遍.甘肃河西走廊是我国玉米制种的主要基地之一,近几年来玉米苗枯病在该区域的发病较为严重.据不完全调查,一般地块发病率在10%左右,发病严重的地块达到15%～20%,造成玉米制种田缺苗、断垅甚至毁种,已构成影响玉米制种高产,制种农户增收的重要问题.因此掌握玉米苗枯病的症状和发生规律,做好玉米制种田苗枯病的防治,对提高玉米制种产量,增加制种农户收益和稳定制种基地都具有很重要的意义. 相似文献
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我国蔬菜产业和科学技术的发展与展望 总被引：1，自引：0，他引：1
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…… 相似文献
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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. 相似文献
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莫曾梅 《农产品加工．学刊》2019,(7):78-80
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。 相似文献
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LI Zhi-liang~ 《保鲜与加工》2004,(7):82-85
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. 相似文献
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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。 相似文献
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《Journal of Landscape Research》2013,(Z1)
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. 相似文献
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果蔬食品的褐变与控制 总被引：9，自引：0，他引：9
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。 相似文献
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Acidity and sweetness in apple and pear 总被引：2，自引：0，他引：2
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. 相似文献