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A hybrid CNN-LSTM model for diagnosing rice nutrient levels at the rice panicle initiation stage

Journal of Integrative Agriculture 2024年第2期23卷 711-723页

作者： Fubing Liao Xiangqian Feng Ziqiu Li Danying Wang chunmei Xu guang chu Hengyu Ma Qing Yao Song Chen School of Computer Science and Technology Zhejiang Sci-Tech UniversityHangzhou 310018China China National Rice Research Institute Chinese Academy of Agricultural SciencesHangzhou 310006China School of Agriculture Yangtze UniversityJingzhou 434025China

Nitrogen(N)and potassium(K)are two key mineral nutrient elements involved in rice growth.Accurate diagnosis of N and K status is very important for the rational application of fertilizers at a specific rice growth stage.Therefore,we propose a hybrid model for diagnosing rice nutrient levels at the early panicle initiation stage(EPIS),which combines a convolutional neural network(CNN)with an attention mechanism and a long short-term memory network(LSTM).The model was validated on a large set of sequential images collected by an unmanned aerial vehicle(UAV)from rice canopies at different growth stages during a two-year experiment.Compared with VGG16,AlexNet,GoogleNet,DenseNet,and inceptionV3,ResNet101 combined with LSTM obtained the highest average accuracy of 83.81%on the dataset of Huanghuazhan(HHZ,an indica cultivar).When tested on the datasets of HHZ and Xiushui 134(XS134,a japonica rice variety)in 2021,the ResNet101-LSTM model enhanced with the squeeze-and-excitation(SE)block achieved the highest accuracies of 85.38 and 88.38%,respectively.Through the cross-dataset method,the average accuracies on the HHZ and XS134 datasets tested in 2022 were 81.25 and 82.50%,respectively,showing a good generalization.Our proposed model works with the dynamic information of different rice growth stages and can efficiently diagnose different rice nutrient status levels at EPIS,which are helpful for making practical decisions regarding rational fertilization treatments at the panicle initiation stage.

关键词： dynamic model of deep learning UAV rice panicle initiation nutrient level diagnosis image classification

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Can canines alone be used for age estimation in Chinese individuals when applying the Kvaal method?

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Forensic Sciences Research 2022年第2期7卷 132-137页

作者： Mujia Li Jiamin Zhao Wenjie Chen Xin Chen guang chu Teng Chen Yucheng Guo Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research College of StomatologyXi’an Jiaotong UniversityXi’anChina Department of Orthodontics Stomatological Hospital of Xi’an Jiaotong UniversityXi’anChina College of Medicine and Forensics Xi’an Jiaotong University Health Science CenterXi’anChina

Due to the secondary dentin formation,the dental pulp undergoes changes in shape throughout life.Based on this phenomenon,the Kvaal method has been applied to various populations for age estimation,and its usefulness has been verified.When applying the Kvaal method to Chinese subjects,we observed a relatively strong correlation between mandibular canines and age.This study notes the correlation between canines and chronological age and is the first to identify which canine is most closely related to chronological age.In addition,a new,simpler formula is determined based on canines according to Kvaal’s methodology.The radiographs of 360 individuals from northern China were selected,from which the widths and lengths of the pulp from four canines were measured according to the Kvaal method.Next,inter-and intra-observer reliabilities were analyzed in order to assess the repeatability of these measurements.The correlation between measurements and age was examined,and Chinese-specific age estimation formulae were derived.The results revealed that the ratios from the left maxillary canine exhibited the strongest correlation with age compared to the other canines,whereas the left mandibular canine showed the weakest correlation,which may contribute to the overall poor correlation of mandibular canines with age.What’s more,the formula derived from the left maxillary canine in this study displayed the highest coefficients of determination,and the formula derived from all canines showed the lowest residuals.Both of these formulae performed better than the Chinese-specific formula derived from six different types of teeth in our previous study,which had formerly possessed the highest coefficients of determination and the lowest residuals.Thus,we concluded that canines do play an important role in age estimation in the Chinese population,and the correlation between maxillary canines and chronological age is stronger than that of mandibular canines,although no distinct trend as to which side is better correlated with age was e

关键词： Forensic sciences forensic odontology age estimation canine secondary dentine Kvaal method Chinese subjects

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Effects of increasing panicle-stage N on yield and N use efficiency of indica rice and its relationship with soil fertility

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The Crop Journal 2022年第6期10卷 1784-1797页

作者： Chang Ye Hengyu Ma Xiu Huang chunmei Xu Song Chen guang chu Xiufu Zhang Danying Wang The State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhou 310006ZhejiangChina

Because of the higher nitrogen(N)recovery efficiency(NRE)of panicle-stage fertilization compared with basal and tillering fertilization,increasing the proportion of N topdressing at the booting stage(panicleN)is recommended and commonly practiced in parts of China.To investigate the effects of increasing panicle-N on grain yield and N use efficiency(NUE)and the relationships of the increase and the rice cultivar and soil fertility status,we increased the percentage of panicle-N from 20%to 40%by correspondingly reducing the N amount applied only at the tillering stage in both high-and low-fertility blue clayey paddy fields in 2018 and 2019.Four indica cultivars with diverse panicle types were used,and their grain yield,dry matter accumulation,and NUE were compared.In high-fertility soil,increasing topdressing panicle-N from 20%to 40%reduced tillering ability and reduced the effective panicle numbers of the multi-and medium-panicle cultivars Huanghuazhan(HHZ),C Liangyouhuazhan(CHZ),and Tianyouhuazhan(THZ).These cultivars gave the greatest yield when 30%of N was supplied as panicle fertilizer,whereas the yield,NRE,N agronomic efficiency(NAE),and nitrogen physiological efficiency(NPE)of the heavy-panicle inbred cultivar Yangdao 6(YD6)continued to increase,resulting in improved dry matter accumulation and grain filling in the late growth stage.The yield,NAE,NRE,and NPE of YD6 peaked when the panicle-N constituted 40%.While in low-fertility soil,the multipanicle cultivar HHZ showed the greatest yield when 30%of fertilizer-N was applied once at the panicle initiation(PI)stage,while the medium-panicle cultivar CHZ showed the greatest yield when the panicle-N percentage was 40%.Our results suggest that the percentage of panicle-N fertilizer should not exceed 30%for multipanicle cultivars,while can be appropriately increased to 40%for heavy-panicle indica cultivars.The effect of increasing topdressing panicle-N on the yield of medium-panicle cultivars was related to soil fertility.The optimum panicle-N percentage was 30%in

关键词： Indica rice Panicle-N Yield Nitrogen use efficiency Soil fertility

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Agronomic performance of drought-resistance rice cultivars grown under alternate wetting and drying irrigation management in southeast China

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The Crop Journal 2018年第5期6卷 482-494页

作者： guang chu Tingting Chen Song Chen chunmei Xu Danying Wang Xiufu Zhang China National Rice Research Institute Chinese Academy of Agricultural Sciences

Compared to drought-susceptible rice cultivars(DSRs),drought-resistance rice cultivars(DRRs)could drastically reduce the amount of irrigation water input and simultaneously result in higher grain yield under water-saving irrigation conditions.However,the mechanisms underlying these properties are unclear.We investigated how improved agronomic traits contribute to higher yield and higher water use efficiency(WUE)in DRRs than in DSRs under alternate wetting and drying(AWD).Two DRRs and two DSRs were field-grown in 2015 and 2016 using two different irrigation regimes:continuous flooding(CF)and AWD.Under CF,no statistical differences in grain yield and WUE were observed between DRRs and DSRs.Irrigation water under the AWD regime was 275–349 mm,an amount 49.8%–56.2% of that(552–620 mm)applied under the CF regime.Compared to CF,AWD significantly decreased grain yield in both DRRs and DSRs,with a more significant reduction in DSRs,and WUE was increased in DRRs,but not in DSRs,by 9.9%–23.0% under AWD.Under AWD,DRRs showed a 20.2%–26.2% increase in grain yield and an 18.6%–24.5% increase in WUE compared to DSRs.Compared to DSRs,DRRs showed less redundant vegetative growth,greater sink capacity,higher grain filling efficiency,larger root biomass,and deeper root distribution under AWD.We conclude that these improved agronomic traits exert positive influences on WUE in DRRs under AWD.

关键词： DSRs alternate wetting and drying(AWD)

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紫叶风箱果叶绿体基因组特征及绣线菊亚科系统发育分析

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草业学报 2024年第3期33卷 161-173页

作者：黄祥何梦瑶王子煊楚光明江萍石河子大学农学院新疆石河子832003 新疆生产建设兵团特色果蔬栽培生理与种质资源利用兵团重点实验室新疆石河子832003

紫叶风箱果是我国近年来从北美引入的观赏性花灌木。为了明确紫叶风箱果叶绿体基因组结构特征,阐明紫叶风箱果在绣线菊亚科中的分类地位,使用Illumina NovaSeq 6000测序平台对其叶绿体基因组进行测序,并组装、注释到了其完整叶绿体基因... 详细信息

紫叶风箱果是我国近年来从北美引入的观赏性花灌木。为了明确紫叶风箱果叶绿体基因组结构特征,阐明紫叶风箱果在绣线菊亚科中的分类地位,使用Illumina NovaSeq 6000测序平台对其叶绿体基因组进行测序,并组装、注释到了其完整叶绿体基因组。结果表明:紫叶风箱果叶绿体基因组呈典型的双链环状四分体结构,全长为159131 bp,大单拷贝区(large single copy,LSC)长87582 bp、小单拷贝区(small single copy,SSC)长18829 bp、反向重复区a(inverted repeats a,IRa)和反向重复区b(inverted repeats b,IRb)长26360 bp;共注释到130个基因,包含83个蛋白编码基因,8个核糖体RNA(ribosomal RNA,rRNA)基因,37个转运RNA(transfer RNA,tRNA)基因和2个假基因。共确定12个最优密码子(UUG、AUU、GUU、GUA、UAA、AAA、UCU、UCC、CCU、ACU、GCU、GGU);密码子使用偏好性主要受自然选择影响,突变等因素对其影响较弱。共有27对长序列重复,87个简单重复序列标记(simple sequence repeat,SSR)位点;psbZ、trnG(UCC)、trnfM(CAU)、trnH(GUG)、psbA、rbcL、rpl20、rps12是紫叶风箱果叶绿体基因组中高核苷酸多态性的基因。系统发育结果表明,风箱果属和绣线梅属的物种亲缘关系较近。

关键词：紫叶风箱果叶绿体基因组密码子使用偏好系统发育

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Solar radiation-use characteristics of indica/japonica hybrid rice (Oryza sativa L.) in the late season in southeast China

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The Crop Journal 2021年第2期9卷 427-439页

作者： Min Yin Shaowen Liu Xi Zheng guang chu chunmei Xu Xiufu Zhang Dangying Wang Song Chen China National Rice Research Institute Chinese Academy of Agricultural SciencesHangzhou 310006ZhejiangChina The Faculty of Agriculture Life and Environmental SciencesZhejiang UniversityHangzhou 310029ZhejiangChina

New indica and japonica hybrid rice cultivars,such as the Yongyou series,provide farmers with very high yield potential.However,information on their canopy light capture and solar radiation use efficiency in the late season is limited.Field experiments were performed to compare the radiation-use parameters of four rice types:indica rice(IR),inbred japonica rice(IJR),hybrid japonica rice(HJR),and hybrid indica/japonica rice(HIJR),from 2016 to 2018 during the late season in Hangzhou,China.The grain yield,aboveground biomass,intercepted solar radiation(SI),and radiation-use efficiency(RUE)of the HIJR were on average respectively 13.4%–53.4%,14.3%–30.6%,7.6%–21.4%,and 8.2%–14.9%higher than those of the HJR,IJR,and IR.The leaf area index(LAI)of the HIJR was 18.2%–57.0%greater than that of the IJR and HJR at four growth stages,resulting in respectively 17.8%–38.5%and 10.7%–42.8%greater canopy light interception rates(LIR)and amount of intercepted solar radiation during the vegetative stage.The prolonged grain-filling stage also led to respectively 33.9%–52.6%and 30.5%–51.4%increases in amounts of incident and intercepted radiation for the HIJR relative to the IR during grain filling.These results indicate that the SI superiority of the HIJR was caused by canopy closure as rapid as that of the IR during the vegetative stage(greater LAI and canopy LIR during the growing season)and a grain-filling stage as long as that of the HJR.For grain-filling stage,differences in leaf Pn between HIJR,IR,and IJR were not significant,suggesting that the greater RUE of the HIJR(12.7%–52.8%higher)than that of the other rice types resulted from improved canopy architecture after flowering(FL).Principal components analysis(PCA)revealed that the superiority of the HIJR in terms of solar radiation use resulted from the greater canopy light capture capability of IR and the prolonged growth period(especially during grain filling)of japonica rice in the late growing season.

关键词： indica/japonica hybrid rice Solar radiation use Canopy light capture Leaf area index

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Effect of various crop rotations on rice yield and nitrogen use efficiency in paddy–upland systems in southeastern China

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The Crop Journal 2018年第6期6卷 576-588页

作者： Song Chen Shaowen Liu Xi Zheng Min Yin guang chu chunmei Xu Jinxiang Yan Liping Chen Danying Wang Xiufu Zhang China National Rice Research Institute Chinese Academy of Agricultural SciencesHangzhou 310006ZhejiangChina Faculty of Agriculture Life and Environmental SciencesZhejiang UniversityHangzhou 310029ZhejiangChina

To evaluate the effects of various rotation systems on rice grain yield and N use efficiency, a paddy–upland cropping experiment(2013–2016) was conducted in southeastern China. The experiment was designed using six different rice––winter crop rotations: rice–fallow(RF),rice–wheat(RW), rice–potato with rice straw mulch(RP), rice–green manure(Chinese milk vetch; RC–G), rice–oilseed rape(RO), and rice–green manure crop(oilseed rape with fresh straw incorporated into soil at flowering; RO–G) and three N rates, N0(0 kg N ha-1), N1(142.5 kg N ha-1), and N2(202.5 kg N ha-1). Average rice yields in the RF(5.93 t ha-1) rotation were significantly lower than those in the rotations with winter crops(7.20–7.48 t ha-1)under the N0 treatment, suggesting that incorporation of straw might be more effective for increasing soil N than winter fallow. The rice yield differences among the rotations varied by year with the N input. In general, the grain yields in the RP and RO–G rotations –were respectively 11.6–28.5% and 14.80–37.19% higher than those in the RF in plots with N applied. Increasing the N rate may have tended to minimize the average yield gap between the RF and the other rotations; the yield gaps were 18.55%, 4.14%, and 0.23% in N0, N1, and N2, respectively. However, the N recovery efficiency in the RF was significantly lower than that in other rotations, except for 2015 under both N1 and N2 rates, a finding that implies a large amount of chemical N loss. No significant differences in nitrogen agronomic efficiency(NAE) and physiological efficiency(NPE) were found between the rotations with legume(RC–G) and non–legume(RO and RW) winter crops, a result that may be due partly to straw incorporation. For this reason, we concluded that the return of straw could reduce differences in N use efficiency between rotations with and without legume crops. The degree of synchrony between the crop N demand and the N supply was evaluated by comparison of nitrogen balance degree(NBD) values. The NBD values in the RP and RW were signific

关键词： Rice(Oryza sativa L.) Paddy–upland rotation Nitrogen use efficiency Winter crops

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山地葡萄智能水肥一体控制系统设计

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安徽农业科学 2024年第11期52卷 187-189页

作者：初光勇姚立国铜仁职业技术学院工学院贵州铜仁554300 贵州师范大学机械与电气工程学院贵州贵阳550025

结合当前丘陵山地葡萄园水肥一体灌溉的需求,设计了一款基于PLC控制的智能水肥一体化系统。该系统以西门子PLC为核心控制器,使用无线通信技术实时采集当前的温湿度、电导率、pH、EC值等参数,利用MCGS软件设计了触摸屏界面。根据当前的... 详细信息

结合当前丘陵山地葡萄园水肥一体灌溉的需求,设计了一款基于PLC控制的智能水肥一体化系统。该系统以西门子PLC为核心控制器,使用无线通信技术实时采集当前的温湿度、电导率、pH、EC值等参数,利用MCGS软件设计了触摸屏界面。根据当前的环境参数对灌溉电机泵进行变频控制,驱动执行机构进行种植环境参数的调节。该智能控制系统能够有效地对葡萄种植过程中的土壤墒情等多种参数以及环境参数进行无线采集传输,并通过PLC进行智能控制。运行试验结果表明:系统运行平稳、响应及时,可提高葡萄种植过程中水肥的利用率。

关键词：水肥一体 PLC 葡萄山地

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水稻无人机直播产量、效益分析及技术要点

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中国稻米 2024年第1期30卷 98-100,107页

作者：童纪氚戎雪利任萍褚光王丹英慈溪市农业机械化技术推广中心浙江慈溪315300 中国水稻研究所杭州310006 余姚市农业机械化技术推广中心浙江余姚315400

以常规水稻品种秀水14为供试品种,比较了机械插秧、行走式机械直播和无人机直播3种种植方式的产量、成本和效益,分析了不同种植方式的工作效率与群体均匀性。结果表明,无人机直播的产量与机械插秧、行走式机械直播无显著差异,但其具有... 详细信息

以常规水稻品种秀水14为供试品种,比较了机械插秧、行走式机械直播和无人机直播3种种植方式的产量、成本和效益,分析了不同种植方式的工作效率与群体均匀性。结果表明,无人机直播的产量与机械插秧、行走式机械直播无显著差异,但其具有播种效率高、群体生长均衡、种植成本低的特点。最后小结了无人机直播技术要点。

关键词：水稻机械插秧行走式机械直播无人机直播

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基于熵值法和FD法的比选模型在钢筋材料比选中的应用

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价值工程 2024年第20期43卷 136-139页

作者：王凤旺初光强凡丽昆明理工大学建筑工程学院昆明650500 云南建投第四建设有限公司曲靖655000 云南创绘电力工程有限公司昆明650224

钢筋因为其受力性能好、适用性强,其在工程中应用范围不断扩大,是目前我国工程领域的主要建材之一。不同工程项目,因其外部环境和使用要求不同,在建造过程中,对钢筋的要求往往不同,如何选取适宜的钢筋是项目建造实施中需要解决的问题,... 详细信息

钢筋因为其受力性能好、适用性强,其在工程中应用范围不断扩大,是目前我国工程领域的主要建材之一。不同工程项目,因其外部环境和使用要求不同,在建造过程中,对钢筋的要求往往不同,如何选取适宜的钢筋是项目建造实施中需要解决的问题,本文基于此问题,选取钢筋比选指标,构建比选模型,结合FD(0-4)法和熵值法确定钢筋比选指标的权重。FD(0-4)法是根据项目的实际情况,将专家的主观经验引入比选模型中,客观化专家对钢筋性能指标的主观意愿的一种方法,该方法确立比选指标的基本权重。熵值法根据比选指标的客观数据变化程度,调整比选指标的基本权重。二种方法结合,量化了专家对项目的理解,考虑了专家意见及经验,又结合了比选指标的客观数据变化情况对比选指标赋权重。该方法为项目建造实施中选取适宜的钢筋提供了思路。

关键词：钢筋比选 FD法信息熵熵值法

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