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Effect of Extreme Natural High Temperature on Seed Setting Rate of Rice(Oryza sativa L.) at Heading and Flowering Stage 被引量:1
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作者 朱镇 赵庆勇 +5 位作者 张亚东 陈涛 姚姝 周丽慧 于新 王才林 《Agricultural Science & Technology》 CAS 2015年第8期1666-1671,共6页
The seed setting rates of total 198 rice cultivars (lines) at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme na... The seed setting rates of total 198 rice cultivars (lines) at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme natural high temperature on seed setting rate of different rice cultivar (line). The results showed that the contin- uous high temperature showed certain effects on the seed setting rates of tested materials, and significant differences were shown in seed setting rate among differ- ent rice cultivars (lines). The seed setting rates differed significantly among indica F1 hybrids derived from different sterile and restorer lines, indicating that the sterile and restorer lines had great effects on heat tolerances of different F~ hybrids. The cor- relation analysis showed that the seed setting rates of conventional indica restorer lines and conventional japonica rice cultivars (lines) were negatively related to the daily highest temperature (P〉0.05), and the seed setting rates of indica F1 hybrids were positively related to the seed setting rates of their restorer lines. Total four in- dica restorer lines, including Ninghuiguangkangzhan, Shuhui 527, Chenghui 3203 and Xianyin-8, and four new japonica rice cultivars (lines), including Wuyinjinghui (B2), Nanjing 4//W3660/Nanjing 44 (B12) and Wuyun 2330/JD6011 (B22) were pre- liminarily screened, and their seed setting rates were all close to the normal level (90%). The screened rice cultivars (lines) showed higher heat tolerances. 展开更多
关键词 High temperature seed setting rate Heading and flowering stage RICE
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Studies on Seed Setting Stability in Associated with Temperature for a Two-Line Hybrid Rice,Liangyoupeijiu 被引量:7
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作者 LuChuan-gen ZONGShou-yu ZOUJiang-shi 《Rice science》 SCIE 2004年第4期191-194,共4页
When being planted in wide areas in southern China (23°23' - 33°23' N, 98°35' - 120°19' E, sea level above 2.7 - 1285 m), Liangyoupeijiu (LYPJ), a two-line hybrid rice combination, ... When being planted in wide areas in southern China (23°23' - 33°23' N, 98°35' - 120°19' E, sea level above 2.7 - 1285 m), Liangyoupeijiu (LYPJ), a two-line hybrid rice combination, showed a seed setting rate of 75.2 - 77.2%, which was lower by 4.3 - 7.5 percent point than that of an indica hybrid rice Shanyou 63 (CK), with similar values of grain yield and coefficients of variation to CK. Sowing during 5-25th of May in Nanjing (32°3' N, 118°48' E), China, LYPJ headed before 4th September, and gave a seed setting rate of 75 - 90%, and grain yield over 1 kg/m2. If the sowing date was delayed to 14 - 15th, June, its heading date would be as late as 17th - 21st September, and seed setting rate would be declined by 10 - 15% in comparison with that on a suitable sowing date. When flowering took place at an average daily temperature range of 13.7 - 28.5℃ for five days, the spikelet fertility (SF) would be increased by 1.9- 10.7%, for each increment of 1℃. The suitable (SF≥90%) and safe (SF≥75%) temperatures for flowering stage were indicated to be 26.5℃ and 22.9℃, respectively. To get a high and stable seed set in cultivating LYPJ, it was recommended that LYPJ would be planted in the areas south of 34癗, and the favorable average daily temperature during flowering stage should be at 26 - 28℃. 展开更多
关键词 RICE intersubspecific hybrid seed setting rate grain yield TEMPERATURE
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Mapping of three QTLs for seed setting and analysis on the candidate gene for qSS-1 in rice(Oryza sativa L.) 被引量:2
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作者 Elsheikh Y M Ahmed ZHANG Yan-pei +5 位作者 YU Jian-ping Rashid M A Rehman ZHANG Zhan-ying ZHANG Hong-liang LI Jin-jie LI Zi-chao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第4期735-743,共9页
The lower seed setting is one of the major hindrances which face grain yield in rice. One of the main reasons to cause low spikelet fertility (seed setting) is male sterility or pollen abortion. Notably, pollen abor... The lower seed setting is one of the major hindrances which face grain yield in rice. One of the main reasons to cause low spikelet fertility (seed setting) is male sterility or pollen abortion. Notably, pollen abortion has been frequently observed in advanced progenies of rice. In the present study, 149 BC2F6 individuals with significant segregation in spikelet fertility were generated from the cross between N040212 (indica) and Nipponbare (japonica) and used for primary gene mapping. Three QTLs, qSS-1, qSS-7 and qSS-9 at chromosomes 1, 7 and 9, respectively, were found to be associated with seed setting. The recombinant analysis and the physical mapping information from publicly available resources exhibited that the qSS-1, qSS-7 and qSS-9 loci were mapped to an interval of 188, 701 and 3741 kb, respectively. The seed setting responsible for QTL qSS-1 was further fine mapped to 93.5 kb by using BC2F7 population of 1 849 individuals. There are 16 possible putative genes in this 93.5 kb region. Pollen vitality tests and artificial pollination indicated that the male gamete has abnormal pollen while the female gamete was normal. These data showed that low seed setting rate relative to qSS-1 may be caused by abnormal pollen grains. These results will be useful for cloning, functional analysis of the target gene governing spikelet fertility (seed setting) and understanding the genetic bases of pollen sterility. 展开更多
关键词 rice (Oryza sativa L.) QTL mapping seed setting pollen sterility
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Molecular mechanisms controlling seed set in cereal crop species under stress and non-stress conditions 被引量:1
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作者 LI Hui-yong Thomas Lübberstedt 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第5期965-974,共10页
Maximizing seed yield is the ultimate breeding goal in important cereal crop species. Seed set is a key developmental stage in the process of seed formation, which determines grain number, seed mass, and realized yiel... Maximizing seed yield is the ultimate breeding goal in important cereal crop species. Seed set is a key developmental stage in the process of seed formation, which determines grain number, seed mass, and realized yield potential, and can be severely affected by abiotic and biotic stresses. However, seed set can also be substantially reduced by genetic factors even under optimal fertilization conditions. The underlying molecular genetic mechanisms are still obscure. In this review, we elucidate the process of seed set of cereal crop species in detail, including development of floral structures, formation of viable gametes, double fertilization, seed development, and abortion. We discuss how genetic and non-genetic factors affect seed set in different development stages. Finally, we will propose novel strategies to study genetic mechanisms controlling seed set and exploit genetic resources to improve seed set in cereal crop species. 展开更多
关键词 maize seed set molecular mechanism
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Treatments of Pollen with Different Solvents Affect the Seed Setting Rate of Rice(Oryza sativa L.)
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作者 HUANG An-ping WANG Wei-ping TAN Yan-ning 《Agricultural Science & Technology》 CAS 2024年第3期1-5,共5页
This study aimed to investigate the effects of treatments of rice pollen with different solvents on the seed setting rate.Rice pollen was treated with ultrapure water,0.5%dimethyl sulfoxide,ethanol(1%,5%,and 8%),and 0... This study aimed to investigate the effects of treatments of rice pollen with different solvents on the seed setting rate.Rice pollen was treated with ultrapure water,0.5%dimethyl sulfoxide,ethanol(1%,5%,and 8%),and 0.5%dimethyl sulfoxide+8%ethanol,and the pollen without treatment was taken as the control.Then,crossing was conducted with the treated rice plants as the male parents and plants subjected to emasculation by warm water as the female parents.The seed setting rates of the male and female parents were then recorded.The results showed that the treatments with different solvents significantly decreased the seed setting rates of both male and female parents.The treatment with 1%ethanol resulted in the highest seed setting rates for both male and female parents,while the treatment with 0.5%dimethyl sulfoxide resulted in the lowest seed setting rates for both parents.Although these solvents affected the seed setting rate of rice,they served as intermediate solvents to dissolve chemicals used in the induction of rice haploids.This study layed a technical foundation for subsequent chemical induction of rice haploids. 展开更多
关键词 RICE SOLVENT POLLEN seed setting rate
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Factors Influencing the Outcrossed Seed-Setting Obstacles of Photo-thermo Sensitive Genie Male Sterile Rice
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作者 CHENXiong-hui WANBang-hui PENGHai-feng LUYan-peng LIAYGKe-qin ZHAOJing 《Rice science》 SCIE 2004年第3期113-119,共7页
Using photo-thermo sensitive genie male rice (PTGMS) Pei' ai 64S, W7415S, W6154S, N26S, Annong S, Nongken 58S, 7001S and 5088S as female parents and conventional indica lines 8258 and U89 as male parents, the fact... Using photo-thermo sensitive genie male rice (PTGMS) Pei' ai 64S, W7415S, W6154S, N26S, Annong S, Nongken 58S, 7001S and 5088S as female parents and conventional indica lines 8258 and U89 as male parents, the factors affecting outcrossed seed-setting were analyzed. The PTGMS had obstacles in outcrossed seed setting influenced by inheritance and environment at varying degrees. Environmental temperature was regarded as the main factor that resulted in the outcrossed seed-setting obstacles. The sensitive stage was at the early stage of grain filling for outcrossed seed setting. There existed remarkable differences at the sensitivity stage, the duration of sensitive period, the sensitive level and the effective level of outcrossed seed-setting obstacles caused by environmental temperature among different PTGMS lines. Therefore, attention should be paid to outcrossed seed-setting obstacles in selection and utilization of PTGMS lines. 展开更多
关键词 RICE photo-thermo sensitive genie male sterile line outcrossing seed setting rate temperature sensitive stage co-relationship
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Effect of ^(211)At treating pollen and stigma on generative cells and seed setting of rice
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作者 JinJian-Nan ChenFang 《Nuclear Science and Techniques》 SCIE CAS CSCD 1998年第3期173-175,共3页
1IntroductionTraditionalγrayisstilusedasamainmutagenicsourcefortheradiationinducedmutationresearchinplants.I... 1IntroductionTraditionalγrayisstilusedasamainmutagenicsourcefortheradiationinducedmutationresearchinplants.Inthemeantime,t... 展开更多
关键词 稻谷 种子 细胞 211At 处理
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Distribution of Rice Grains on Panicle Axis and Its Relationship with Seed-Setting Ability in Liaoning, China
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作者 XU Zheng-jin CHEN Wen-fu SHUN Zhan-hui ZHANG Shu-lin LIU Li-xia ZHOU Shu-qing 《Agricultural Sciences in China》 CAS CSCD 2006年第3期202-208,共7页
Studies were conducted with rice varieties developed in recent years in Liaoning Province of China as test materials. Results showed that the varieties tested could be divided into three types: (1) the high-yieldi... Studies were conducted with rice varieties developed in recent years in Liaoning Province of China as test materials. Results showed that the varieties tested could be divided into three types: (1) the high-yielding (HYV), (2) the mediumyielding (MYV), and (3) the low-yielding (LYV). The panicle population was in the order of HYV〈 MYV 〈 LYV, while the grain number per panicle and seed-setting rate were just opposite. There was no significant difference in the 1 000-grain weight. Biomass was higher in HYV than in MYV and LYV, while the harvest index was higher in HYV and MYV than in LYV. Yield was inversely correlated with panicle population, but positively correlated with the grain number per panicle, seed-setting rate, the number of primary and secondary branch grains, seed density and harvest index. Yield was most closely linked with the grain number per panicle which was determined chiefly by the number of secondary branch grains and to a lesser degree by seed density and the number of primary branch grains. The seed-setting rate of the secondary branches was positively correlated with that of the whole panicle and yield. The peak value of primary branches for HYV, MYV and LYV was 12-14, 10-13 and 8-12, respectively. LYV had fewer secondary branch grains, while MYV and HYV had more. Such grains distributed mainly in the middle and lower parts of panicle axis for LYV and in the middle and upper parts for MYV and HYV. 展开更多
关键词 rice grain distribution primary branch secondary branch seed-setting ability
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Effects of changing assimilate supply on starch synthesis in maize kernels under high temperature stress
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作者 Teng Li Shumei Wang +5 位作者 Qing Liu Xuepeng Zhang Lin Chen Yuanquan Chen Wangsheng Gao Peng Sui 《Journal of Integrative Agriculture》 2026年第2期639-647,共9页
High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assim... High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assimilate supply or direct inhibition on kernel metabolism.To clarify these mechanisms,a heat-sensitive maize hybrid,Xianyu 335 (XY),was exposed to 30℃/20℃ (maximum/minimum temperature,control) and 40℃/30℃ for seven consecutive days during the seed setting stage.Synchronous pollination (SP),apical pollination (AP),and shading treatments were applied to manipulate the inherent source–sink ratio in maize plants.Results showed that apical kernel weight decreased by 11.9%under 40℃ in the SP treatment.The ^(13)C content,starch accumulation,and cell-wall invertase (CWIN) activity also declined by 15.9,36.7,and 16.4%,respectively,under HT.In the shading treatment,40℃/30℃ caused even greater reductions in^(13)C content,starch accumulation,and CWIN activity due to diminished assimilate supply.Conversely,in the AP treatment,starch content and CWIN activity increased by 22.0 and 18.5%,respectively,under 40℃/30℃,resulting in kernel weight and ^(13)C content similar to those in SP and shading treatments regardless of temperature.Consistent with apical kernels under AP,HT did not negatively affect middle kernels in either SP or shading treatments,as kernel weight and starch content remained unchanged under HT.Although all kernels were exposed to the same HT or control environment,their responses varied a lot.The impaired starch synthesis in apical kernels under HT was rescued by increasing carbon supply via AP treatment.The contrasting performance among middle kernels,apical kernels under AP,and apical kernels under SP or shading indicates that reduced carbon supply is a critical factor underlying inhibited starch accumulation.Our findings provide a theoretical basis for further understanding kernel abortion under HT. 展开更多
关键词 high temperature stress MAIZE seed setting stage cell wall invertase starch synthesis
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MeJA对光温敏雄性不育小麦BS141开花习性及异交结实的影响
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作者 岳洁茹 侯起岭 +6 位作者 苑少华 郝小聪 白秀成 王长华 张风廷 赵昌平 孙辉 《麦类作物学报》 北大核心 2026年第1期123-129,共7页
茉莉酸甲酯(MeJA)可以诱导作物开花习性。为进一步明确MeJA对小麦光温敏雄性不育系开花习性、浆片及异交结实的调控作用,于花后第2天对小麦光温敏雄性不育系BS141进行4 mmol·L^(-1)MeJA浸穗处理,同时以浸水穗作为对照,研究MeJA对... 茉莉酸甲酯(MeJA)可以诱导作物开花习性。为进一步明确MeJA对小麦光温敏雄性不育系开花习性、浆片及异交结实的调控作用,于花后第2天对小麦光温敏雄性不育系BS141进行4 mmol·L^(-1)MeJA浸穗处理,同时以浸水穗作为对照,研究MeJA对不育系每日开颖率、日不同时间开花变化、柱头外露率、开颖角度、浆片形态及异交结实的影响。结果表明,MeJA处理后,BS141开颖率当天达到最大,比对照高出31.45个百分点,第2天开始显著低于对照,第4天-第5天与对照没有显著差异。在开颖率最大的时候授粉,可使BS141异交结实率比对照提高24.77个百分点。MeJA处理后BS141的日开花高峰期主要集中在13:00,而对照较分散。上午10:00统计BS141柱头外露率,发现MeJA处理的BS141柱头外露率在5 d内均低于对照。MeJA处理的BS141每日最大开颖角度整体低于对照。由此说明通过喷施外源MeJA,可使小麦光温雄性不育系开颖率在喷施当天达到最大,且开花高峰较集中,此时授粉可显著提高异交结实率,但喷施MeJA对柱头外露率和最大开颖角度作用不显著。 展开更多
关键词 小麦光温敏雄性不育系 茉莉酸甲酯 开花习性 浆片 异交结实
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基于Seed集的半监督核聚类 被引量:2
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作者 李昆仑 张超 +1 位作者 曹铮 刘明 《计算机工程与应用》 CSCD 北大核心 2009年第20期154-157,共4页
提出了一种新的半监督核聚类算法——SKK-均值算法。算法利用一定数量的标记样本构成seed集,作为监督信息来初始化K-均值算法的聚类中心,引导聚类过程并约束数据划分;同时还采用了核方法把输入数据映射到高维特征空间,并用核函数来实现... 提出了一种新的半监督核聚类算法——SKK-均值算法。算法利用一定数量的标记样本构成seed集,作为监督信息来初始化K-均值算法的聚类中心,引导聚类过程并约束数据划分;同时还采用了核方法把输入数据映射到高维特征空间,并用核函数来实现样本之间的距离计算。在UCI数据集上进行了数值实验,并与K-均值算法和核-K-均值算法进行了比较。 展开更多
关键词 半监督聚类 seed 核方法 K-均值
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一种基于Seeds集和成对约束的主动半监督聚类算法 被引量:2
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作者 陈志雨 王慧君 +1 位作者 胡明 刘钢 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2017年第3期664-672,共9页
针对半监督聚类算法中监督信息使用不充分,监督信息中信息含有量低的问题,提出一种结合主动学习的半监督聚类算法.首先结合使用数据的类别标记和成对约束信息,指导Kmeans聚类过程,设计出一种基于Seeds集和成对约束的半监督聚类算法SC-Km... 针对半监督聚类算法中监督信息使用不充分,监督信息中信息含有量低的问题,提出一种结合主动学习的半监督聚类算法.首先结合使用数据的类别标记和成对约束信息,指导Kmeans聚类过程,设计出一种基于Seeds集和成对约束的半监督聚类算法SC-Kmeans;其次将主动学习算法引入到SC-Kmeans中,以尽量小的代价选取信息含有量更高的监督信息,提高SC-Kmeans算法的聚类精度;最后在UCI标准数据集上进行仿真实验.实验结果表明,该算法取得了较好的聚类效果,有效提高了聚类准确率. 展开更多
关键词 半监督聚类 Kmeans算法 成对约束 seeds集 主动学习
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不同父本对籽叶两用茶树‘金茶18’花粉直感效应的影响
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作者 李朵姣 胡新荣 +4 位作者 沈英姿 江丽 袁名安 王丽鸳 郑寨生 《茶叶科学》 北大核心 2026年第1期50-60,共11页
茶树是异花授粉植物,为探究花粉直感效应对茶籽的影响,以‘金茶18’为母本,‘苔茶’‘丽早香’‘黔湄1号’‘鸠坑大叶’和‘黔湄809’为父本开展人工授粉试验,比较不同授粉组合的坐果率、茶籽经济性状和品质性状差异,采用主成分分析法... 茶树是异花授粉植物,为探究花粉直感效应对茶籽的影响,以‘金茶18’为母本,‘苔茶’‘丽早香’‘黔湄1号’‘鸠坑大叶’和‘黔湄809’为父本开展人工授粉试验,比较不同授粉组合的坐果率、茶籽经济性状和品质性状差异,采用主成分分析法进行综合评价。结果表明,不同品种授粉的茶籽干籽质量、干仁质量、含油率和脂肪酸含量等指标均表现出花粉直感效应。5个授粉组合中,以‘苔茶’‘黔湄1号’和‘鸠坑大叶’为父本的组合坐果率显著高于自然授粉组;其中父本为‘黔湄1号’的种子直径、干籽质量和干仁质量与自然授粉组接近,显著高于其他组合;以‘苔茶’‘丽早香’为父本的茶籽含油率、脂肪酸总量和不饱和脂肪酸含量显著高于其他组合。通过主成分分析法对6个授粉组合进行综合评价,结果显示,以‘苔茶’‘丽早香’为父本的授粉组合和自然授粉组合的综合评分位列前3。进一步分析表明,‘苔茶’作为‘金茶18’的授粉树,可显著提高其坐果率、茶籽含油率及不饱和脂肪酸含量,适宜作为‘金茶18’的授粉茶树品种。 展开更多
关键词 ‘金茶18’ 花粉直感效应 人工授粉 坐果率 茶籽性状
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谷子(Setaria italica Beauv.)高异交结实雄性不育系“81-16”的柱头性状观察 被引量:18
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作者 崔贵梅 牛天堂 +2 位作者 张福耀 袁爱萍 孙毅 《作物学报》 CAS CSCD 北大核心 2007年第1期149-153,共5页
谷子不育系异交结实率低严重制约着杂交种大面积应用于生产。本研究证明柱头外露程度与异交结实率呈显著正相关(r0.001=0.9597**)。山西省农业科学院经济作物研究所成功选育出谷子光敏雄性不育突变系“81-16”,其不育度为100%,异交结实... 谷子不育系异交结实率低严重制约着杂交种大面积应用于生产。本研究证明柱头外露程度与异交结实率呈显著正相关(r0.001=0.9597**)。山西省农业科学院经济作物研究所成功选育出谷子光敏雄性不育突变系“81-16”,其不育度为100%,异交结实率达61%。用植物形态解剖学方法证明,“81-16”雌蕊生活力强,柱头完全外露,接受花粉的有效面积大,是其异交结实率高的主要原因。本文还提出应重视母本柱头性状选育,并加强谷子杂交种制种技术研究。 展开更多
关键词 谷子雄性不育系 异交结实率 雌蕊 柱头
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基于seeds集和频繁项集挖掘的半监督聚类算法 被引量:2
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作者 赵倩 尚学群 王淼 《计算机工程与应用》 CSCD 北大核心 2010年第8期123-126,176,共5页
半监督聚类在无监督学习中通过对少量监督信息的有效利用提高聚类性能。提出一种基于seeds集的半监督聚类算法,它采用Apiori算法对初始seeds集和扩大规模后seeds集的数据进行频繁项集挖掘,使得数据中存在的噪音数据和误标记数据得到净... 半监督聚类在无监督学习中通过对少量监督信息的有效利用提高聚类性能。提出一种基于seeds集的半监督聚类算法,它采用Apiori算法对初始seeds集和扩大规模后seeds集的数据进行频繁项集挖掘,使得数据中存在的噪音数据和误标记数据得到净化、修正,以改善seeds集质量,提高聚类性能。该算法使用带权χ2测试这一数学模型作为分类规则度量指标,以对无标记数据进行类标签值预测。实验结果显示,所提出的结合了频繁项集挖掘和带权χ2测试的基于seeds集的半监督聚类算法不仅改善了seeds集质量,也提高了预测结果的精确度,优化了聚类性能。 展开更多
关键词 半监督聚类 频繁项集挖掘 带权χ2测试 seeds集
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基于Seeds集和成对约束的半监督三支聚类集成 被引量:3
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作者 姜春茂 吴鹏 李志聪 《计算机应用》 CSCD 北大核心 2023年第5期1481-1488,共8页
聚类集成使用合适的策略融合多个具有差异性的基聚类成员,能够有效提高聚类结果的稳定性、鲁棒性和准确率。当前聚类集成的研究较少利用已知的先验信息,面对复杂数据时难以刻画对象与类簇之间明确的归属关系。因此,提出一种基于Seeds集... 聚类集成使用合适的策略融合多个具有差异性的基聚类成员,能够有效提高聚类结果的稳定性、鲁棒性和准确率。当前聚类集成的研究较少利用已知的先验信息,面对复杂数据时难以刻画对象与类簇之间明确的归属关系。因此,提出一种基于Seeds集和成对约束的半监督三支聚类集成方法。首先,基于已有的标签信息提出一种新的三支标签传播算法构造基聚类成员;其次,提出一种半监督三支聚类集成框架集成基聚类成员,构造出一致性相似矩阵,并利用成对约束信息对该矩阵进行优化调整;最后,将三支谱聚类作为一致性函数对相似矩阵进行聚类,得到最终集成结果。在多个UCI真实数据集上的实验结果表明,与基于类簇的相似分区算法(CSPA)、超图分区算法(HGPA)、元类簇算法(MCLA)、标签传播算法(LPA)、Cop-Kmeans等半监督聚类集成算法相比,所提方法的归一化互信息(NMI)、调整兰德系数(ARI)和F测度在绝大多数据集上取得了最优值,获得了相对更好的聚类集成结果。 展开更多
关键词 三支决策 聚类集成 三支聚类 成对约束 半监督 seeds集
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基于Level Set的交互式快速分割算法 被引量:3
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作者 孙海鹏 余伟巍 席平 《工程图学学报》 CSCD 北大核心 2011年第3期45-51,共7页
三维医学图像数据量大,并且受噪声、边界模糊等原因的影响,致使三维分割过程消耗时间较长,容易产生欠分割或过度分割。针对以上问题,提出一种基于Level Set的三维快速分割算法,采用Fast Marching获取二维分割区域,优化轮廓边界,利用直... 三维医学图像数据量大,并且受噪声、边界模糊等原因的影响,致使三维分割过程消耗时间较长,容易产生欠分割或过度分割。针对以上问题,提出一种基于Level Set的三维快速分割算法,采用Fast Marching获取二维分割区域,优化轮廓边界,利用直线数值微分算法(Digital Differential Analyzer,DDA)提取轮廓像素;进一步引入扫描线种子填充思想,实现医学图像的三维快速分割。实验结果表明,上述算法能够快速准确地分割出感兴趣区域。 展开更多
关键词 计算机应用 医学图像三维分割 Levelset算法 数值微分算法 扫描线种子填充
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优良山茶属植物杂交育种研究 被引量:2
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作者 韦晓娟 杨卓颖 +4 位作者 张幸 武建云 伍思宇 梁晓静 林茂 《热带作物学报》 北大核心 2025年第1期83-93,共11页
为培育出观赏价值高的山茶新品种,开展山茶属植物组内、组间的杂交育种研究,以金花茶组(Sect.Chrysantha Chang)、红山茶组[Sect.Camellia(L.)Dyer]、古茶组(Sect.Archecamellia Sealy)、油茶组(Sect.oleifera Chang)、离生雄蕊组(Sect.... 为培育出观赏价值高的山茶新品种,开展山茶属植物组内、组间的杂交育种研究,以金花茶组(Sect.Chrysantha Chang)、红山茶组[Sect.Camellia(L.)Dyer]、古茶组(Sect.Archecamellia Sealy)、油茶组(Sect.oleifera Chang)、离生雄蕊组(Sect.Corallina Sealy)、越南茶组[Sect.Piquatia(Pierre)Sealy]的部分种及品种共14个,设计42个杂交组合,其中组内杂交8个,组间杂交24个,正反交组合10个。结果表明:42个组合共授粉2016朵,座果274个,座果率为13.6%,收获杂交果72个,结实率为3.57%,种子199粒,获得杂交苗104株,出苗率为52.26%。宛田红花油茶♀×广宁红花油茶♂获得的杂交苗数量最多,达45株,其次是广宁红花油茶♀×宛田红花油茶♂,得苗14株。多数杂交苗叶片大小、形状、光泽处于父母本的中间性状,远缘杂交获得的杂交幼苗表现出一些可以作为早期鉴别杂交苗真实性的特征;宛田红花油茶♀×广宁红花油茶♂、宛田红花油茶♀×越南抱茎茶♂、宛田红花油茶♀×普通金花茶♂组合的杂交亲和性较好,授粉数量分别为32、30、53,结实率分别为12.5%、10.0%、22.6%,授粉数量越多,结实率则越高,代表性更强。组内杂交、组外远缘杂交均显示宛田红花油茶和广宁红花油茶不论作为父本或母本开展杂交育种,可育性均较高,是优良的杂交亲本。越南抱茎茶不论作为父本或母本,与金花茶组植物杂交亲和性均较好。普通金花茶、香花油茶在作为父本可育性强,表明普通金花茶和香花油茶则适合作为杂交父本。 展开更多
关键词 山茶属 杂交育种 座果率 结实率 可育性 杂交苗
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Cultivar and Soil Fertilizer Treatment Affect Seed Production of Sweet Yellow Yam (<i>Dioscorea dumetorum</i>) on Highly Acidic Soils of the Western Highlands Region of Cameroon
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作者 Somo Toukam Gabriel Mahbou Godswill Ntsomboh-Ntsefong +2 位作者 Tiokeng Marie Noel Ateko Benoit Nono Emmanuel Youmbi 《American Journal of Plant Sciences》 2021年第9期1387-1409,共23页
The popularization of <i>Dioscorea dumetorum</i> (Dioscoreaceae), a nutritious yam species is still marginal due to constraints such as the low interest of research, poor cultural practices, insufficient a... The popularization of <i>Dioscorea dumetorum</i> (Dioscoreaceae), a nutritious yam species is still marginal due to constraints such as the low interest of research, poor cultural practices, insufficient and expensive seeds, pests, and diseases. The latter pushes producers to use about 50% of their harvest as seed for the next planting season. The lack of a specific fertilizer formulation for yam production on the oxysols of Cameroon is another constraint. This study was aimed at enhancing the availability of quality seeds through the characterization of five yam accessions. One experiment was performed to determine the effect of cultivar and origin of tuber sets on their germination rate. The <span>second concerned the evaluation of cultivars and soil treatment effects on ag</span>ronomic parameters of yam seedlings. Yam cultivars were subjected to nine fertilizer formulations as follows: T0: no fertilizer;T1: mycorrhizal fungi (MF) + 150 g manure + peanut waste;T2: 25 g chemical fertilizer (20.10.10);T3: MF + peanut waste;T4: 16 g chemical fertilizer (12.6.20);T5: 25 g (20.10.10) +100 g CaO + 150 g manure;T6: 100 g CaO + 150 g manure;T7: 20 g tropicote + 2 g DAP (Diammonium phosphate, a reference starter fertilizer coded N18P46) + 100 g CaO + 150 g manure;and T8: mycorrhiza. These treatments were tested in a factorial design. Results show that Ibo sweet 3 and Mabondji sweet white 1 yam accessions were less affected by anthracnose disease on the aerial parts. Guzang 1 showed the best germination rate and yield, making it appropriate for cultivation in the region. Soil treatments, T2, T5, T7 and T8 significantly increased the yield of yam cultivars. Mycorrhiza treatment alone gave a better response to seed weight, indicating the interest of this biofertilizer as a solution for good seedling production. These fertilizer treatments can be recommended to farmers for more seed production with optimum seed weight (300 g). 展开更多
关键词 Dioscorea dumetorum Mini set Yam seed Production MYCORRHIZA Fertilizer Soil Acidity
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松嫩平原两种生境条件下羊草种群有性生殖特征的比较 被引量:1
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作者 王月霖 初丽爽 +6 位作者 刘莉莉 丰吉 刘志扩 杨允菲 李海燕 兰理实 由成成 《草业科学》 北大核心 2025年第6期1496-1506,共11页
有性生殖在无性系禾草的繁殖策略中占据着重要地位。外界生境条件的变化以及无性系禾草自身构件数量均可以直接或间接影响其有性生殖。对围栏封育草甸和弃耕地不同叶片数量羊草(Leymus chinensis)生殖分株的数量特征、生物量积累与分配... 有性生殖在无性系禾草的繁殖策略中占据着重要地位。外界生境条件的变化以及无性系禾草自身构件数量均可以直接或间接影响其有性生殖。对围栏封育草甸和弃耕地不同叶片数量羊草(Leymus chinensis)生殖分株的数量特征、生物量积累与分配、有性生殖特征进行了比较分析。结果表明:1)弃耕地的羊草种群分株总密度、生殖分株密度和抽穗率均显著高于围栏封育(P<0.05),而围栏封育中营养分株占比显著高于弃耕地;多生殖分株、高抽穗率的弃耕地具有产生更多种子的潜力,围栏封育中的羊草更倾向于营养繁殖。2)围栏封育草甸,叶片数量多的生殖分株茎生物量、叶生物量、总生物量和叶生物量分配显著高于叶片数量少的;弃耕地中叶片数量少的生殖分株的叶生物量、花序生物量和总生物量显著高于围栏封育;羊草生殖分株具有的多叶片并不是在所有生境下都有益于自身。3)弃耕地中的羊草生殖分株叶生物量分配、茎生物量分配、花序生物量分配、生殖分配Ⅰ、生殖分配Ⅱ和生殖再分配显著高于围栏封育;弃耕地羊草生殖分株高、花序长、种子数、种子生物量、百粒重和结实率等有性生殖特征也均显著高于围栏封育;相较于围栏封育,弃耕地中羊草种子在数量上占据优势,资源更多的投入到有效的种子生产中。研究结果表明,两种生境下不同叶片数羊草生殖分株的有性生殖特征和资源分配策略有着较强的可塑性。 展开更多
关键词 优良禾草 生境 构件 生殖分株 叶片数 结实特征 繁殖策略
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