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基于卷积神经网络的列当种子发芽识别方法

草业学报 2024年第8期33卷 112-121页

作者：沈祺嵘严俊叶晓馨桑玉莹单启玲张琪藤安徽大学资源与环境工程学院安徽合肥230601

列当是一种极具破坏力的寄生性杂草,目前难以用常规方法根除。通过使用发芽刺激物可以诱导列当“自杀性萌发”,因此识别特定发芽刺激物下的种子发芽率至关重要。针对显微镜下人眼视觉对列当种子发芽判断标准不统一和耗时耗力等问题,本... 详细信息

列当是一种极具破坏力的寄生性杂草,目前难以用常规方法根除。通过使用发芽刺激物可以诱导列当“自杀性萌发”,因此识别特定发芽刺激物下的种子发芽率至关重要。针对显微镜下人眼视觉对列当种子发芽判断标准不统一和耗时耗力等问题,本研究提出一种基于卷积神经网络的列当种子发芽识别算法。首先,培育列当种子并采用显微镜采集发芽和未发芽的种子构建列当图像库;然后,通过搭建卷积神经网络来提取列当图像的特征实现种子发芽识别,通过试验对比优化超参数,得到适合列当种子识别的OB-Net模型;最后,通过试验图像验证,本研究模型可达到95.2%的识别准确率;与现有主流网络模型进行对比证明了构建的OB-Net模型在列当种子识别方面具有最高的精度和较快检测速度。本研究的列当种子发芽识别方法可以为相关发芽刺激物的研究提供有效的理论支撑。

关键词：列当种子发芽识别卷积神经网络特征提取

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Effect of N Fertilizers on Root Growth and Endogenous Hormones in Strawberry

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Pedosphere 2009年第1期19卷 86-95页

作者： WANG Bo LAI Tao HUANG qi-Wei YANG Xing-Ming shen qi-rong College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China） Faculty of Horticulture Soochow University Suzhou 215006 （China）

Endogenous hormones play an important role in the growth and development of roots. The objective of this research was to study the effect of four types of N fertilizers on the root growth of strawberry (Fragaria ananassa Duchesne) and the endogenous enzymes of indole-3-acetic acid (IAA), abscisic acid (ABA), and isopentenyl adenosine (iPA) in its roots and leaves using enzyme-linked immunosorbent assay. Application of all types of N fertilizers significantly depressed (P ≤ 0.05) root growth at 20 d after transplanting. Application of organic-inorganic fertilizer (OIF) as basal fertilizer had a significant negative effect (P ≤ 0.05) on root growth. The application of OIF and urea lowered the lateral root frequency in strawberry plants at 60 d (P ≤ 0.05) compared with the application of two organic fertilizers (OFA and OFB) and the control (CK). With the fertilizer treatments, there were the same concentrations of IAA and ABA in both roots and leaves at the initial growth stage (20 d), lower levels of IAA and ABA at the later stage (60 d), and higher iPA levels at all seedling stages as compared to those of CK. Thus, changes in the concentrations of endogenous phytohormones in strawberry plants could be responsible for the morphological changes of roots due to fertilization.

关键词： endogenous hormone organic and inorganic N fertilizers root growth strawberry

Enzyme Activity in Water-Stable Soil Aggregates as Affected by Long-Term Application of Organic Manure and Chemical Fertiliser

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Pedosphere 2013年第1期23卷 111-119页

作者： LIU Yi-Ren LI Xiang shen qi-rong XU Yang-Chun Jiangsu Provincial Key Laboratory for Solid Organic Waste Utilization College of Resources and Environmental SciencesNanjing Agricultural University Institute of Soil Fertilizer and Resource Environment Jiangxi Academy of Agricultural Sciences

The activities of invertase, protease, urease, acid phosphomonoesterase, dehydrogenase, and catalase in different fractions of waterstable aggregates (WSA) were examined in long-term (26 years) fertilised soils. The long-term application of organic manure (OM) with chemical fertiliser (CF) significantly increased macroaggregate and decreased microaggregate percentages, enhanced the mean weight diameter, and significantly increased soil total carbon (TC) and total nitrogen (TN) contents of WSA in different size fractions. Combined fertilisation with OM and CF also increased invertase, protease, urease, acid phosphomonoesterase, dehydrogenase, and catalase activities of WSA in different size fractions. Enzyme activities were higher in macroaggregates than in microaggregates. The distribution of enzyme activities generally followed the distribution of TC and TN in WSA. The geometric mean of the enzyme activities in different WSA of OM-treated soils was significantly higher than that in soils treated with 100% CF or no fertiliser. The results indicated that the long-term combined application of OM with CF increased the aggregate stability and enzyme activity of different WSA sizes, and consequently, improved soil physical structure and increased soil microbial activity.

关键词： distribution mean weight diameter stability total carbon total nitrogen

Mechanisms of Enhanced Rice Growth and Nitrogen Uptake by Nitrate

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Pedosphere 2007年第6期17卷 697-705页

作者： DUAN Ying-Hua YIN Xiao-Ming ZHANG Ya-Li shen qi-rong College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China）

Rice is being increasingly cultivated in intermittently irrigated regions and also in aerobic soil in which Nitrate （NO3^- ） plays important role in nutrition of plant. However, there is no information regarding the influence of nitrate on the overall growth and uptake of nitrogen （N） in rice plant. Solution culture experiments were carried out to study the effects of NO^3- on the plant growth, uptake of N, and uptake kinetics of NH4^＋ in four typical rice （Oryza sativa L.） cultivars （conventional indica, conventional japonica, hybrid indica, and hybrid japonica）, and on plasma membrane potential in roots of two conventional rice cultivars （indica and japonica） at the seedling stage. The results obtained indicated that a ratio of 50/50 NH4^＋-N/NO3^--N increased the average biomass of rice shoots and roots by 20% when compared with that of 100/0 NH4^＋-N/NO3^--N. In case of the 50/50 ratio, as compared with the 100/0 ratio, total N accumulated in shoots and roots of rice increased on an average by 42% and 57%, respectively. Conventional indica responds to NO3^- more than any other cultivars that were tested. The NO^3- supply increased the maximum uptake rate （Vmax） of NH4^＋ by rice but did not show any effect on the apparent Michaelis-Menten constant （Km） value, with the average value of Vmax for NH4^＋ among the four cultivars being increased by 31.5% in comparison with those in the absence of NO3^-. This suggested that NO3^- significantly increased the numbers of the ammonium transporters. However, the lack of effect on the Km value also suggested that the presence of NO3^- had no effect on the affinity of the transporters for NH4^＋. The plasma membrane potential in the roots of conventional indica and japonica were greatly increased by the addition of NO3^- , suggesting that NO3^- could improve the uptake of N by roots of the rice plant. In conclusion, the mechanisms by which NO3^- enhances the growth and N uptake of rice plant was found by the increased value of Vm

关键词： ammonium uptake nitrate nutrition nitrogen uptake plasma membrane potential rice

Aromatic Moieties from Matured Chicken Manure and Agriculture Residues Compost Suppress Growth of Lepidium sativum L. and Trichoderma harzianum

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Pedosphere 2013年第6期23卷 826-834页

作者： LUO Yi-Hong ZHANG Dong-qing YU Guang-Hui shen qi-rong Agricultural Ministry Key Lab of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River Jiangsu Key Lab for Organic Solid Waste UtilizationCollege of Resources and Environmental SciencesNanjing Agricultural University Baoshan Environmental Protection Bureau

To better understand the role of organic matter(OM)prepared from chicken manure and agriculture residues compost on the growth of plants(Lepidium sativum L.)and antagonistic fungi(Trichoderma harzianum),we analyzed the structure and composition of extracted OM using fluorescence excitation-emission matrix(EEM)spectroscopy and solid-state13C cross-polarization magic-anglespinning nuclear magnetic resonance(13C CPMAS NMR)*** results showed that the EEM contours of water-extracted OM(WEOM)and alkali-extracted OM(AEOM)were ***,solid-state13C CPMAS NMR spectroscopy demonstrated that water extraction could not proportionally pull out aromatic moieties(112–145 ppm)from compost,but the alkali method in proportion extracted both carbohydrates(65–85 ppm)and aromatic *** results suggest that AEOM may better reflect the bulk OM composition of compost,and one should be cautious when applying WEOM as an alternative indicator of total compost *** investigations demonstrated that,compared to carbohydrates,aromatic moieties played a predominant role in growth suppression of Lepidium sativum *** and Trichoderma harzianum.

关键词： excitation-emission matrix spectroscopy extracted organic matter fluorescence reginal integration analysis nuclear magnetic resonance spectroscopy

Nitrate Effect on Rice Growth and Nitrogen Absorption and Assimilation at Different Growth Stages

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Pedosphere 2006年第6期16卷 707-717页

作者： DUAN Ying-Hua ZHANG Ya-Li shen qi-rong WANG Song-Wei College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China

The effect of nitrate （NO3^-） on rice （Oryza sativa L.） growth as well as N absorption and assimilation during different growth stages was examined using three typical rice cultivars. Dry weight, yield, N uptake, nitrate reductase activity （NRA） in leaves, and glutamine synthetase activity （GSA） in roots and leaves during their entire growth periods, as well as the kinetic parameters of ammonium （NH4^＋） uptake at the seedling stage, were measured with solution culture experiments. Results indicated that addition of NH4^＋-N and NO3^-N at a ratio of 75：25 （NH4^＋＋NO3^- treatment） when compared with that of NH4^＋-N alone （NH4^＋ treatment） increased the dry weight of ‘Nanguang＇ cultivar by 30% and ‘Yunjing 38＇ cultivar by 31%, and also increased their grain yield by 21% and 17%, respectively. For the four growth stages, the total N accumulation in plants increased by an average of 36% for ‘Nanguang＇ and 31% for ‘Yunjing 38＇, whereas the increasing effect of NO3^- in the ‘4007＇ cultivar was only found at the seedling stage, in the NH4^＋＋NO3^- treatment compared to the NH4^＋ treatment, NRA in the leaves increased by 2.09 folds, and GSA increased by 92% in the roots and 52% in the leaves of the three cultivars. NO3^- supply increased the maximum uptake rate （Vmax） in the ‘Nanguang＇ and ‘Yunjing 38＇ cultivars, reflecting that the NO3^- itself, not the increasing N concentration, increased the uptake rate of NH4^＋ by rice. There was no effect on the apparent Michaelis-Menten constant （Kin） of the three cultivars. Thus, some replacement of NH4^＋ with NO3^-could greatly improve the growth of rice plants, mainly on account of the increased uptake of NH4^＋ promoted by NO3^-, and future studies should focus on the molecular mechanism of the increased uptake of NH4^＋ by NO3^-.

关键词： growth stages N absorption and assimilation nitrate N uptake rice

Effect of Nitrate on Activities and Transcript Levels of Nitrate Reductase and Glutamine Synthetase in Rice

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Pedosphere 2008年第5期18卷 664-673页

作者： CAO Yun FAN Xiao-rong SUN Shu-Bin XU Guo-Hua HU Jiang shen qi-rong College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China）.

Real-time polymerase chain reaction analysis was used to compare the effect of NO3^- on the activities of nitrate reductase （NR） and glutamine synthetase （GS）, and the transcript levels of two NR genes, OsNial and OsNia2, two cytosolic GS1 genes, OsGln1;1 and OsGln1;2, and one plastid GS2 gene OsGln2, in two rice （Oryza sativa L.） cultivars Nanguang （NG） and Yunjing （Y J）. Both cultivars achieved greater biomass and higher total N concentration when grown in a mixed N supply than in sole NH4^＋ nutrition. Supply of NO3^- increased NR activity in both leaves and roots. Expression of both NR genes was also substantially enhanced and transcript levels of OsNia2 were significantly higher than those of OsNial. NO3 also caused an increase in GS activity, but had a complex effect on the expression of the three GS genes. In roots, the OsGln1;1 transcript increased, but OsGln1;2 decreased. In leaves, NO3^- had no effect on the GS1 expression, but the transcript for OsGln2 increased both in the leaves and roots of rice with a mixed supply of N. These results suggested that the increase in GS activity might be a result of the complicated regulation of the various GS genes. In addition, the NO3-induced increase of biomass, NR activity, GS activity, and the transcript levels of NR and GS genes were proportionally higher in NG than in Y J, indicating a stronger response of NG to NO3^- nutrition than YJ.

关键词： ammonium glutamine synthetase nitrate nitrate reductase Oryza sativa L.

中国生物肥料与有机肥料研究三十年:回顾与展望

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植物营养与肥料学报 2024年第7期30卷 1262-1273页

作者：张瑞福陈玉孙新丽徐志辉缪有志张楠刘东阳沈其荣南京农业大学资源与环境科学学院江苏南京210095

生物肥料与有机肥料是环境友好的绿色肥料,在培肥耕地、改良土壤、提高农产品品质中发挥重要作用,是支撑农业绿色发展、保障国家粮食安全的重要投入品。自20世纪中叶,我国化肥工业的快速发展为促进粮食持续增产提供了充足的无机养分;到2... 详细信息

生物肥料与有机肥料是环境友好的绿色肥料,在培肥耕地、改良土壤、提高农产品品质中发挥重要作用,是支撑农业绿色发展、保障国家粮食安全的重要投入品。自20世纪中叶,我国化肥工业的快速发展为促进粮食持续增产提供了充足的无机养分;到20世纪90年代,我国肥料投入中化肥占比达到最高,有机肥料等的施用相应降至最低。对化肥的依赖导致了耕地质量退化、农田环境污染、农产品质量下降等一系列问题,严重影响了我国耕地的可持续利用和农业可持续发展,因此我国加大了对生物肥料与有机肥料的研究。三十年来,我国生物肥料与有机肥料在基础研究、应用研究和产业化方面都取得了日新月异的进展。我国的生物肥料研究从最初的根瘤菌等固氮功能逐步扩展到溶磷解钾等活化养分功能,进一步发展到消减土壤障碍与增强作物抗逆等非养分功能;从单一菌种发展到多菌种及合成菌群,产品类型从单纯的菌剂发展到生物有机肥和复合微生物肥料,产业规模和技术水平显著提升。有机肥料研究从关注堆肥过程中的有机养分转化到提高堆肥效率的技术工艺和有害因子的消除与阻控等。近年来,在“双碳”战略背景下,清洁低碳堆肥以及通过施用有机肥快速提升土壤有机质、增加土壤固碳成为新的研究热点。本文对过去三十年我国生物肥料与有机肥料研究重点、代表性成绩、产业化路径等进行了全面回顾和总结,新形势下国家农业发展重大战略需求以及科技的突破仍将支撑生物肥料和有机肥的快速发展,由此提出了未来的一些研究重点。

关键词：生物肥料有机肥料研究重点产业化

Humic-Like Substances from Different Compost Extracts Could Significantly Promote Cucumber Growth

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Pedosphere 2012年第6期22卷 815-824页

作者： XU Da-Bing WANG qiu-Jun WU Yun-Cheng YU Guang-Hui shen qi-rong HUANG qi-Wei Jiangsu Provincial Key Lab for Organic Solid Waste Utilization Nanjing Agricultural UniversityNanjing 210095(China)

The effects of direct extracts of compost (DEC), aerated fermentation extracts of compost (AFEC) and non-aerated fermentation extracts of compost (NAFEC) on cucumber growth and the action mechanisms were evaluated based on the structure and activity analysis of humic-like substances. AFEC increased cucumber growth most significantly, followed by DEC and NAFEC, which was insignificant compared to the control treatment. Humic-like substances from compost extracts played an important role in promoting cucumber growth. Application of humic-like substances stimulated auxin-like activity and increased chlorophyll content and nitrogen accumulation in plants. The positive auxin-like activity of humic-like substances could be attributed to the relative distribution of special carbon groups, such as those with a large amount of peptidic and carbohydratic groups or with a low content of phenolic groups. In conclusion, the best growth promotion by application of AFEC was mainly attributed to the humic-like substances in the AFEC.

关键词： auxin-like activity 13C nuclear magnetic resonance chemical structure elemental composition analysis