期刊文献+
共找到13篇文章
< 1 >
每页显示 20 50 100
利用图像和机器学习检测大豆作物幼苗期玉米杂苗 被引量:7
1
作者 Paulo FLORES 张昭 +2 位作者 Jithin MATHEW Nusrat JAHAN John STENGER 《智慧农业(中英文)》 2020年第3期61-74,共14页
在大豆-玉米轮作生产过程中,玉米杂苗会与大豆苗竞争水和肥料,而且很容易遮住大豆苗,影响害虫(如玉米根虫)的防控,降低大豆品质。因此,在大豆幼苗期及时检测出玉米杂苗并对其进行处理非常重要。传统的人工检测方法主观性强、效率低,传... 在大豆-玉米轮作生产过程中,玉米杂苗会与大豆苗竞争水和肥料,而且很容易遮住大豆苗,影响害虫(如玉米根虫)的防控,降低大豆品质。因此,在大豆幼苗期及时检测出玉米杂苗并对其进行处理非常重要。传统的人工检测方法主观性强、效率低,传感器和算法的发展为自动检测玉米杂苗提供了更好的解决方案。本研究在温室环境下模仿田间条件,待玉米和大豆发芽后,连续5天用因特尔RealSense D435相机采集彩色图像,并人工裁剪幼苗图像区域,在此基础上对图像进行分割和去噪。在采集图像形状、色彩和纹理特征值后,对所采集的特征值进行权重分析,保留前10种重要的特征值导入基于特征的机器学习算法中进行模型训练和预测。预测结果表明,支持向量机模型(SVM)、神经网络(NN)和随机森林(RF)的预测精度分别为85.3%,81.5%和82.6%。将数据集导入GoogLeNet和VGG-16两种深度学习模型进行训练,预测精度分别为96.0%和96.2%。VGG-16模型在区分大豆幼苗和玉米杂苗中有较好的表现,彩色图像和VGG-16模型组成的系统可以自动检测大豆生长过程中玉米杂苗的情况,为农民提供准确的信息,帮助其进行生产决策和田间管理。 展开更多
关键词 玉米-大豆轮作 玉米杂苗 图像处理 机器学习 深度学习 支持向量机(SVM)
在线阅读 下载PDF
长江口中华绒螯蟹蟹苗与常见野杂蟹苗主要形态的初步鉴别及资源利用 被引量:1
2
作者 张列士 朱选才 李军 《水产科技情报》 2001年第2期59-63,共5页
在长江口及邻近沿岸带共收集到蟹类 6科 1 4属 1 7种 ,已能鉴定的大眼幼体有中华绒螯蟹( Eriocheir sinensis)、天津厚蟹 ( H elicetientsinensis)等 5种 ,对这 5种蟹类进行形态鉴别的主要依据为头胸甲和前额缘外形及第二触角。
关键词 中华绒螯蟹 形态鉴别 资源利用 长江口
在线阅读 下载PDF
40%乙·氰悬乳剂防除夏玉米田杂草药效试验 被引量:1
3
作者 闫新华 高忠文 +1 位作者 孔斌 王金信 《农药科学与管理》 CAS 2000年第5期26-27,31,共3页
田间试验表明40 %乙·氰悬乳剂对玉米田杂草具有良好的防治效果 ,最佳用量175~200mL/mu,药后45d防效在90 %以上 ,鲜重防效达93 %以上。
关键词 乙·氰悬乳剂 玉米田杂苗 除草效果
在线阅读 下载PDF
果树定植防“五苗”与僵苗
4
作者 金建良 《湖北林业科技》 2001年第3期61-61,共1页
关键词 果树 栽培 定植 杂苗
在线阅读 下载PDF
水稻秧苗期的化除方法
5
作者 顾松华 《中国农垦》 2000年第7期25-25,共1页
关键词 水稻田 杂苗群落 化学除草
在线阅读 下载PDF
玉米制种应该注意密度问题 被引量:1
6
作者 于俊琴 刘艳香 宋加馥 《天津农林科技》 2004年第1期19-19,共1页
关键词 玉米 制种 密度 杂苗 播种 亲本
在线阅读 下载PDF
The Effects of UV-B Radiation on Maize at the Seedling Stage 被引量:2
7
作者 解备涛 王庆美 +5 位作者 张海燕 李爱贤 候夫云 汪宝卿 董顺旭 张立明 《Agricultural Science & Technology》 CAS 2015年第11期2456-2461,共6页
In this study, maize plant seedlings were grown in soilless cultures, with and without ^-B radiation at a close of 5.4 kJt(m2-d). Three clays later, it was found that the treatment of UV-B radiation significantly re... In this study, maize plant seedlings were grown in soilless cultures, with and without ^-B radiation at a close of 5.4 kJt(m2-d). Three clays later, it was found that the treatment of UV-B radiation significantly reduced such characteristics as biomass, plant height, leaf area, and so on. Also, the photosynthesis of the maize was inhabited, the anti-oxid activity decreased, and the MDA concentration increased with the UV-B radiation exposure. The maize presented visible hybrid vigor under the control condition, while the hybrid vigor under UV-B radiation barely emerged in biomass, plant height, leaf area, and physiological metabolic index. 展开更多
关键词 MAIZE UV B radiation Hybrid vigor Seedling stage
在线阅读 下载PDF
Effects of Pb Stress on Seed Germination and Seedling Growth of Two Weed Species Seeds 被引量:3
8
作者 刘俊华 姚志刚 《Agricultural Science & Technology》 CAS 2016年第12期2726-2731,共6页
Objective] The aim was to investigate the effects of Pb stress on seed germination and seedling growth of Chenopodium glaucum and Chenopodium serot-inum L. [Method] With C. glaucum and C. serotinum as the study object... Objective] The aim was to investigate the effects of Pb stress on seed germination and seedling growth of Chenopodium glaucum and Chenopodium serot-inum L. [Method] With C. glaucum and C. serotinum as the study objects, the ef-fects of different concentrations of Pb on their seed germination and seedling growth, as wel as on the leaf SOD, POD and CAT activity were studied primarily. [Result] The germination potential of both the two kinds of weed seeds increased first and then decreased with the increase of Pb concentration. The germination po-tential of C. serotinum and C. glaucum seeds reached the peak at Pb concentration of 25 and 50 mg/L, respectively. With the increase of Pb treatment concentration, the germination rate, germination index and vigor index of C. serotinum and C. glaucum seeds decreased, and their bud length and root length also reduced gradu-al y. ln overal , the leaf SOD, POD and CAT activity of C. glaucum and C. serot-inum_ seedlings increased first and then decreased with the increased treatment concentration of Pb. The leaf SOD and POD activity of C. glaucum and C. serot-inum seedlings reached the maximum at Pb concentration of 200 and 100 mg/L, respectively, and the leaf CAT activity reached the maximum at Pb concentration of 100 mg/L. [Conclusion] The two Chenopodium species had strong tolerance to Pb stress, and they could be used as alternative accumulator plants of soil Pb contami-nation. 展开更多
关键词 Pb stress WEED Seed germination Seedling growth
在线阅读 下载PDF
Differential Gene Expression Between Wheat Hybrids and Their Parental Inbreds in Primary Roots 被引量:10
9
作者 倪中福 孙其信 +1 位作者 吴利民 解超杰 《Acta Botanica Sinica》 CSCD 2002年第4期457-462,共6页
To provide an insight into the molecular basis of heterosis, differential display of mRNA was used to analyze the difference of gene expression between wheat (Triticum aestivum L.) heterotic hybrid A, nonheterotic hyb... To provide an insight into the molecular basis of heterosis, differential display of mRNA was used to analyze the difference of gene expression between wheat (Triticum aestivum L.) heterotic hybrid A, nonheterotic hybrid B and their parental inbreds in the primary roots. By using 5′ end random primers in combination with three one-base-anchored primers, it was found that 22.5% and 22.9% of 877 total displayed cDNAs were differentially expressed between hybrid A, B and their parents, respectively. Both quantitative and qualitative differences in gene expression between hybrids and their parental inbreds were obvious, indicating that the patterns of gene expression in hybrids alter significantly as compared to their corresponding parents. On the other hand, by using MADS-box gene specific 5′ end primer for DDRT-PCR, we found that nearly all of the displayed cDNA fragments were polymorphic between hybrids and their parents, and major difference occurred in qualitative level, in which hybrid specific-expressed and silenced genes are the major two patterns, suggesting that MADS-box gene may be important for manifestation of differential gene expression and wheat heterosis. In comparison with our previous results by using seedling leaves, it is indicated that differential gene expression between hybrids and parents is dependent on the tissues tested, and more differentially expressed genes were observed in the primary roots than in the seedling leaves. Therefore, it is concluded that the expressions of both randomly displayed cDNAs and transcription factor genes, such as MADS-box, alter significantly between hybrids and their parents, which might be responsible for the observed heterosis. 展开更多
关键词 differential display gene expression HETEROSIS WHEAT primary roots
在线阅读 下载PDF
大豆高产栽培技术(三)
10
作者 高培 《农村科学实验》 2005年第5期10-11,共2页
八、加强田间管理。适时铲瞠 1.及时间苗 非精量播种地块,在大豆两个对生单叶展开至第一片复叶展开前,进行人工间苗。间去弱苗.病苗、杂苗,留大苗、壮苗、纯苗,按计划密度一次定苗。
关键词 高产栽培技术 大豆 田间管理 精量播种 复叶 杂苗
在线阅读 下载PDF
Nutrient element contents of cutting seedlings of hybrid species (Liriodendron chinense x tulipifera) 被引量:2
11
作者 张晓平 方炎明 丁雨龙 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期307-310,共4页
The cutting seedlings of Liriodendron chinense x tulipifera were treated with the different concentrations of auxin (treatment1: IBA of 50 gkg-1 + NAA of 300 gkg-1; treatment2: IBA of 100 gkg-1 + NAA of 300 gkg-1). Th... The cutting seedlings of Liriodendron chinense x tulipifera were treated with the different concentrations of auxin (treatment1: IBA of 50 gkg-1 + NAA of 300 gkg-1; treatment2: IBA of 100 gkg-1 + NAA of 300 gkg-1). The biomass and the nutrient element contents for different organs (root, stem, leaf) of cutting seedling of Liriodendron chinense x tulipifera were measured by the dry method, Kjeldahl method and Atomic Absorption Spectroscopy method. The result showed that the biomass of root, stem, and leaf of the cutting seedling treated with auxin was all remarkably increased. The contents of element C in root, stem and leaf had no significant difference between the control and auxin treatments, while the contents of N, P, K and Ca in stem were much lower than that in leaf and root. Variance analysis showed that for the same organ with different concentration treatment of auxin, the four nutrient elements (N, P, K, and Ca) had no significant difference in contents, while there existed significant or very significant difference in contents of the four nutrient elements in different organs with the same concentration auxin treatment. The N, P, K and Ca contents were very low in cutting seedlings; as a result, additional fertilizer should be applied to the seedlings when they were planted in the field. 展开更多
关键词 Hybrid species (Liriodendron chinense x tulipifera) Cutting Seedlings Nutrient contents
在线阅读 下载PDF
Production Technique Regulations of Apple Hybrid Seedlings
12
作者 Xiangmin SUO Jie HAO +4 位作者 Tiezheng LIU Xinmin YAN Xueying LI Xiange WANG Jianzhong FENG 《Agricultural Science & Technology》 CAS 2017年第10期1870-1872,共3页
The production technique of apple hybrid seedlings was systematically summarized, and the technology regulations were made, including rootstock cultivation, interstock grafting, hybrid seeds preparation and hybrid see... The production technique of apple hybrid seedlings was systematically summarized, and the technology regulations were made, including rootstock cultivation, interstock grafting, hybrid seeds preparation and hybrid seedlings grafting. This technical specification provides a unified technical specification for hybrid apple seedling breeders, and is of important guiding significance for the production of apple in Hebei Province. 展开更多
关键词 APPLE HYBRID SEEDLINGS Standardized cultivation
在线阅读 下载PDF
防治食用菌菌种受污染措施
13
作者 李秀娥 姜金虎 《北京农业》 2001年第4期17-18,共2页
关键词 食用菌 杂苗 青霉菌 木霉菌 链孢霉菌 防治
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部