共查询到17条相似文献，搜索用时 250 毫秒
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为明确广东省杂草稻的发生与分布情况以及生物学特征,为广东省杂草稻的防治提供基本信息,通过采用目测法和样方法点面结合,调查广东省栽培稻田杂草稻的发生与危害情况,对调查的杂草稻生物学特征与其发生率、发生密度、综合危害指数综合进行分析,结果显示,广东省杂草稻的发生率为0.00%~33.11%,发生密度最低的县（市）约0,最高约18株/m2,综合危害指数都在20%以上。以雷州、惠东尧封开和恩平最为严重,杂草稻密度依次为18.10、2.52、1.60、0.96株/m2,综合危害指数依次为56.00%、45.00%、29.20%和15.80%。杂草稻植株较高、分蘖较强、叶色偏淡、成熟早、易落粒、种皮红色、籽粒偏籼型,得出广东省不同稻作区杂草稻发生与分布情况依次为粤西南稻作区>粤中南稻作区>粤中北稻作区>粤北稻作区,且杂草稻发生率为直播田>抛秧田>移栽田。 相似文献
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我国种植水稻历史悠久,地域广阔,是世界稻米主产国之一。我国每年水稻种植面积约3500万hm2,约占粮食作物播种面积的29%。总产稻谷1.92亿t,占粮食总产量的42%,无论种植面积和产量,在我国粮食作物中都居首位。为有效地控制稻田杂草稻的危害,现针对杂草稻的发生特 相似文献
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江苏沿江地区杂草稻的生物学特性及危害调查 总被引：5，自引：0，他引：5
【目的】明确江苏沿江地区杂草稻的发生现状、危害和生物学特性,掌握其鉴别方法。【方法】采用目测法和样方法点面结合,调查江苏沿江地区6个市的28个县（市、区）的直播稻田杂草稻的发生率、发生密度、综合危害指数,定点研究6个地点的杂草稻生物学特性及其危害性。【结果】杂草稻在各县（市）的发生率从78%-100%不等,发生密度最低的县（市）约2株/m2,平均最高约9株/m2,综合危害指数都在20%以上,导致栽培稻减产8.3%-82.3%;泰州、扬州和常州的危害相对更重。综合6个地点的调查结果显示杂草稻与栽培稻主要区别为：杂草稻的叶环和叶耳呈紫红色,植株基部褐色;苗期生长旺盛,分蘖力强、分蘖角大于栽培稻20°以上,株高高出8-10 cm;株型松散;单株结实量高于栽培稻3倍以上,繁育系数显著高于栽培稻,但结实率较低,为78%-86%,千粒重仅为18.93-20.10 g;成熟期早1月左右并显早枯。【结论】江苏沿江地区的杂草稻发生量大且危害严重;杂草稻与栽培稻有形态学差异;杂草稻的分蘖初期、扬花期是人工拔除的适宜时期。 相似文献
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杂草稻分类及起源研究进展 总被引：2，自引：0，他引：2
杂草稻已成为影响全球水稻生产的恶性杂草.关于分类及起源一直是杂草稻研究的热点问题,但至今尚无定论.杂草稻是指在人工栽培稻田中或稻田周边耕地里,通过种子落粒等对自然环境的极强适应能力而自然繁衍其群体,对稻田生态系统产生不利影响的稻属植株或群体.一般可根据形态特性、籼粳亚种属性、栽培型和野生型对杂草稻进行分类.杂草稻可能起源于栽培稻与野生稻的基因渐渗、籼粳亚中间杂交和栽培稻种间杂交,部分杂草稻可能是普通野生稻演化成原始栽培稻的过渡形态,栽培稻与杂草稻自然异交可产生更多的杂草稻类型.因此,提出了杂草稻分散起源的假说,认为杂草稻很可能是多次起源,而且杂草稻在不同地区可能是分散起源.对利用籼粳基因组分化和稻属驯化相关基因研究杂草稻起源的可行性及重要意义进行了分析. 相似文献
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WANG Hao-quan DAI Wei-min ZHANG Zi-xu LI Meng-shuo MENG Ling-chao ZHANG Zheng LU Huan SONG Xiao-ling QIANG Sheng 《农业科学学报》2023,22(1):149-169
Rice, the main food crop in China, has been sporadically reported to suffer from weedy rice infestation. However, the overall occurrence and distribution pattern of Chinese weedy rice remains unclear because a systematic survey has not been conducted. In order to reveal the infestation of Chinese weedy rice, a field survey was conducted in 999 sampling sites all over the rice-growing regions in China from 2009 to 2016 using seven-scale visual scoring of the level of weed infestation. Weedy rice was found 39% occurrence incidence in a total of 387 sites. The sampling sites with 50% or higher overall weedy rice infestation index mainly radiated from Jiangsu, Heilongjiang, Ningxia and Guangdong to the whole East China, Northeast China, Northwest China and South China. A total of 45 morphological characters from 287 populations (collected simultaneously with the field survey) out of those occurred sites were observed and analyzed using multivariate analysis in common gardens with the same cultivation conditions in 2017 and 2019. Canonical correlation analysis showed that 45 morphological characters were significantly related to the latitude, mean temperature, minimum temperature, precipitation and mean diurnal range factors. The 287 weedy rice populations were divided into three morphological groups with climate-dependent geographical differentiation: strong tiller type only in Jiangsu, large leaf type in South China and Central China and large grain type mainly in North China. Weedy rice seriously infested rice fields and had a geography, climate and cultivated rice type-dependent morphological and biotype differentiation in China. It is suggested to pay attention to the harmfulness of weedy rice and adopt comprehensive control strategies. 相似文献
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近年来,杂草稻在稻田呈蔓延趋势,稻田中杂草稻的大量存在对栽培稻产量及品质造成危害,进而造成严重经济损失.为指导农民区分杂草稻与栽培稻并及时防治,文章对杂草稻的形态特征进行研究.结果表明,杂草稻不完全叶长于松粳系列品种的栽培稻,与龙稻系列和东农系列的栽培稻无差异;有叶舌、叶耳及叶毛,与栽培稻无差异;杂草稻有芒,呈褐色、黄色、紫色,长26~79 mm,栽培稻无芒或芒很短;杂草稻的颖壳色有褐色、稻草色、黄带黑斑等多种颜色,栽培稻的颖壳呈黄色;千粒重较栽培稻轻 相似文献
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通过野外实地调查以及田间抽样系统调查的方法,对福寿螺在江西省范围内的发生分布及其在稻田的消长规律进行了研究。调查发现,2015年福寿螺已分布在江西省的34个县市区,发生总面积为55 586 hm~2;田间抽样系统调查结果表明,江西省早稻田中福寿螺在6月中旬出现成螺高峰期,在7月上旬出现产卵高峰期,1代幼螺高峰期出现在7月上中旬;在中稻田中,福寿螺成螺和幼螺高峰均出现在8月中下旬,产卵高峰出现在8月下旬;双季晚稻田福寿螺成螺和幼螺在10月上中旬达高峰,产卵高峰期出现在10月中下旬。长期浅水灌溉处理稻田的福寿螺消长规律与干湿交替处理的相似,其成螺、幼螺和卵块密度与干湿交替处理稻田的无明显差异,表明干湿交替处理稻田对福寿螺种群增长无明显抑制作用。 相似文献
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水稻是中国重要的粮食作物之一,年种植面积3000万hm2,约占粮食作物种植面积的1/3,稻谷产量占粮食总产量的45%。生物灾害是影响中国水稻稳产、高产的重要因素之一。全国每年因水稻病虫害为害虽经防治仍然造成经济损失400～500万t。稻飞虱、稻纵卷叶螟、水稻螟虫、稻瘟病、纹枯病是中国水稻生产上为害严重的几种重要的病虫害,2001—2004年全国水稻病虫害发生面积超过8500khm2次,其中2003年稻飞虱、稻纵卷叶螟、水稻螟虫发生面积占总发生面积的72.5%。近年来水稻病虫在全国的发生特点表现为:一、大部地区病虫害发生较重,重大病虫暴发强度大。发生危害严重的病虫有水稻螟虫、稻纵卷叶螟、稻瘟病,发生程度中等以上的有稻飞虱、水稻纹枯病;二、次要病虫上升,为害加重。一些过去偶发性的次要病虫水稻条纹叶枯病、水稻细菌性条斑病、稻曲病等,发生面积扩大,发生程度明显上升,已经或正逐渐上升为重要病虫害;三、发生面积较大,波及面广。2004年以来,西北太平洋副热带高压强度偏强,厄尔尼诺事件将进一步发展,将有利于迁飞性害虫稻飞虱、稻纵卷叶螟的发生为害。近年来,随着粮食种植效益的提高,早稻面积将继续回升,单双季稻混栽面积将进一步加大,对水稻螟虫、稻飞虱、稻纵卷叶螟发生为害有利;部分地区部分高产、优质但易感稻瘟病的水稻品种种植,有利于稻瘟病的发生流行。 相似文献
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Mapping the fallowed area of paddy fields on Sanjiang Plain of Northeast China to assist water security assessments 
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下载免费PDF全文 LUO Chong LIU Huan-jun FU Qiang GUAN Hai-xiang YE Qiang ZHANG Xin-le KONG Fan-chang 《农业科学学报》2020,19(7):1885-1896
Rice growth requires a large amount of water, and planting rice will increase the contradiction between supply and demand of water resources. Paddy field fallowing is important for the sustainable development of an agricultural region, but it remains a great challenge to accurately and quickly monitor the extent and area of fallowed paddy fields. Paddy fields have unique physical features associated with paddy rice during the flooding and transplanting phases. By comparing the differences in phenology before and after paddy field fallowing, we proposed a phenology-based fallowed paddy field mapping algorithm. We used the Google Earth Engine(GEE) cloud computing platform and Landsat 8 images to extract the fallowed paddy field area on Sanjiang Plain of China in 2018. The results indicated that the Landsat8, GEE, and phenology-based fallowed paddy field mapping algorithm can effectively support the mapping of fallowed paddy fields on Sanjiang Plain of China. Based on remote sensing monitoring, the total fallowed paddy field area of Sanjiang Plain is 91 543 ha. The resultant fallowed paddy field map is of high accuracy, with a producer(user) accuracy of 83%(81%), based on validation using ground-truth samples. The Landsat-based map also exhibits high consistency with the agricultural statistical data. We estimated that paddy field fallowing reduced irrigation water by 384–521 million cubic meters on Sanjiang Plain in 2018. The research results can support subsidization grants for fallowed paddy fields, the evaluation of fallowed paddy field effects and improvement in subsequent fallowed paddy field policy in the future. 相似文献