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云南甘蔗生产发展状况分析 总被引：2，自引：0，他引：2
《中国糖料》2015,(5)
为了解云南省甘蔗生产的发展趋势和种植状况,利用云南省甘蔗统计数据,分析了云南1949—2012年甘蔗种植面积、产量、单产的变化趋势;并利用近年来云南分县的甘蔗统计数据,分析了云南甘蔗产量空间分布和变化情况以及单产的空间分布情况,以期为云南甘蔗产业的发展提供科学依据。 相似文献
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基于自适应增强的BP模型的浙江省茶叶产量预测 总被引：1，自引：0，他引：1
本文采用1999—2018年浙江省59个县市的茶叶产量数据和地面气象要素驱动数据,提出了基于产量等级因子的自适应增强的反向传播（BP）神经网络模型的茶叶产量预测机制。首先分析提取了种植面积、年平均气温、3—7月的平均相对湿度、年平均相对湿度等11个影响因子,然后构建浙江省茶叶产量预测模型。试验结果表明,基于产量等级因子的自适应增强的BP模型算法相关系数达到0.893,相对误差的平均值和方差分别为0.187和0.136。在试验数据选取方面,相较于距离预测年份较远的数据,采用临近预测年份的数据,预测精度较高。根据本研究的茶叶产量预测机制,建立了浙江省茶叶产量预测误差空间分布图,其中1级优势区的平均误差为18.32%,2级次优势区为16.73%,3级一般产区为22.69%。预测模型能够实现浙江省各县市的茶叶产量预测,对茶叶生产的宏观管理具有一定指导意义。 相似文献
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我国亚热带地区甘蔗产量的模型模拟 总被引：2，自引：0，他引：2
应用基于甘蔗生长机理的APSIM-Sugarcane动态模拟模型对南宁一块试验蔗地的甘蔗产量进行动态模拟和验证。结果表明,蔗茎和蔗糖的模拟产量与实测产量分别相差440g/m2和330g/m2,地上部干物重模拟值与实测值的线性回归方程斜率为1.1,决定系数为0.94,说明模型对甘蔗产量的模拟具有较高的准确性。回归模型表明,降水量、太阳辐射和气温的累积量也可精确反映甘蔗产量的动态变化。APSIM-Sugarcane模型的应用可为我国甘蔗产业的精准化管理提供科学依据。 相似文献
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基于神经网络的甘蔗产量预测系统 总被引：3，自引：1，他引：2
首次将人工神经网络应用到甘蔗产量的预测中,介绍了ＢＰ网络模型及其算法,讨论了系统的开发方法,并对系统进行验证。对广西忻城糖厂蔗区８８／８９－９７／９８榨季的甘蔗单产和相应的气象条件运行结果表明模型具有较高的精度,复测误差在－５．３－１０．２％。 相似文献
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该文简述了神经网络概念、发展历史、适用范围及算法，详细介绍了神经网络在甘蔗产量预测中的应用技术和软件开发过程，并以实例说明其应用效果 相似文献
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以"贵妃"芒果为试材,利用电子鼻检测果实气味响应值,同时测定果实的糖酸度,采用偏最小二乘法(PLS)和BP神经网络建立了基于电子鼻的可溶性固形物、可滴定酸的品质预测模型。两种方法构建的可溶性固形物含量预测模型的建模集相关系数R均大于93%,可滴定酸测模型的建模集相关系数R均大于91%。其中,BP神经网络建模集的相关系数R均略高于PLS,建模均方均根误差(RMSEM)也较低。而预测集相关系数R和预测均方根误差(RMSEP)与PLS的相当或略低,BP神经网络模型对芒果糖酸度预测准确性略好于PLS。结果表明,PLS和BP神经网络模型的预测性能均较好,利用电子鼻技术对芒果品质进行无损伤检测是可行的。 相似文献
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该文简述了神经网络概念、发展历史、适用范围及算法，详细介绍了神经网络在甘蔗产量预测中的应用技术和软件开发过程，并以实例说明其应用效果。 相似文献
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新台糖系列甘蔗品种是我国重要的甘蔗品种和亲本,利用其作为亲本,易于培育出更为优良的杂交后代。本研究利用7个新台糖系列甘蔗亲本,配制20个组合,对其杂交组合进行黑穗病抗性评价,结果表明:20个组合人工接种黑穗病菌后全部发病,参试组合平均丛感病率与平均茎感病率为极显著正相关;组合间丛感病率和茎感病率均为极显著差异,说明人工接种胁迫试验能够将抗病性强、中、弱的组合鉴别出来,从而将感病严重的组合进行淘汰;通过聚类分析,20个组合抗病性可分为3种类型,组合3和12号聚为一类,发病最重,平均丛感病率、平均茎感病率分别为24.74%、11.5%和28.48%、18.44%,该类组合可以予以淘汰,组合7、10、11和13号聚为二类,发病中等,其余组合聚为三类,发病较轻。 相似文献
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草地贪夜蛾是联合国粮农组织全球预警的重大迁飞性害虫之一,具有寄主广泛性、适生区域广、迁飞能力强等特点,存在暴发为害甘蔗的灾害性威胁。2019年,云南景谷、陇川、耿马、勐海、盈江、澜沧甘蔗产区相继发现草地贪夜蛾危害甘蔗,发生面积1232.81hm^2、成灾面积415.67hm^2,最高百株虫口数32.3头。结合我国蔗区甘蔗生产实际,抓住低龄幼虫防治关键期,加强普查,通过科学引导,采取生态调控、天敌保护利用、生物防治、药剂防治和成虫诱杀等防控措施,实现草地贪夜蛾防治处置率≥90%,绿色防控技术应用比例≥30%,综合防控效果达到85%,危害损失率控制在8%以内的目标。 相似文献
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马铃薯产量、品质、加工等方面都较其他作物有更大的提升空间,但由于四倍体马铃薯存在遗传基础狭窄且复杂、难以创新等诸多问题阻碍了相关研究的深入开展。利用马铃薯单倍体或双单倍体植株有望解决上述诸多难题。马铃薯单倍体具有加速育种过程、提高选择效率等优点。马铃薯单倍体的获得包括花药培养、花粉培养、孤雌生殖、子房培养。其中,花药培养因更易取材,并且得到胚性细胞团、愈伤组织或胚状体的几率更大等优点而研究最为广泛。获得单倍体植株的成功率与试验材料的基因型、培养条件、培养基添加物等诸多因素相关。根据不同的诱导方法简要阐述了中国马铃薯单倍体研究的历史及进展。 相似文献
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于2013-2014连续两年对云南主要水稻种植区的水稻病毒病进行了调查,发现当前为害云南水稻的病毒病主要有水稻条纹叶枯病、南方水稻黑条矮缩病、水稻矮缩病和水稻齿叶矮缩病。其中,条纹叶枯病是当前为害云南水稻最严重的病毒病,部分田块最高发病率可达15.0%;其次是水稻矮缩病,调查田块最高发病率达10.0%;南方水稻黑条矮缩病的平均发病率达5.3%;水稻齿叶矮缩病只在局部地区发生且发病率都不高。对云南当前发生较普遍的RSV不同分离物RNA3基因间隔区(IR3)及RNA4基因间隔区(IR4)开展了分子变异分析。根据不同RSV分离物IR3、IR4核苷酸序列构建系统进化树,所分析的RSV分离物均可被划分为两个组,部分云南分离物和云南以外的中国、日本、韩国分离物聚在Ⅰ组,其余绝大多数云南分离物单独聚在Ⅱ组。不同RSV分离物的IR3和IR4长度差异较大,按每10个核苷酸的长度差异进行划分,均可划分为A、B、C三种不同的类型。部分RSV云南分离物IR3、IR4中有17-21nt的序列与其水稻、小麦和大麦等寄主的部分序列相同,这可能是病毒在进化过程中与寄主植物发生了重组。云南RSV分离物的IR3、IR4分子变异较大,可能与其特殊的地理、生态条件有一定的相关性。 相似文献
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云南省水稻生产现状及绿色发展对策 总被引：2，自引：0，他引：2
云南是农业大省,水稻是云南省最主要的粮食作物。针对水稻生产中存在的“生产成本快速增长、成本利润率快速下降、种稻效益低下、稻米自给率较低、品牌影响力不够、优质多抗高产品种供给不足、水稻机械化程度较低、水稻绿色高产高效栽培和施肥技术欠缺”等一系列制约水稻绿色发展的瓶颈,从“稳定水稻种植面积,提高种稻比较效益,加大绿色高效的优质多抗高产新品种选育与应用,研究与应用全程机械化技术、化肥农药减量增效技术和稻田种养结合技术”等方面提出对策建议,确保云南稻米安全,打造云南高原特色的绿色稻米产业,促进云南水稻产业的绿色持续稳定发展。 相似文献
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Keisuke Katsura Shuhei Maeda Iskandar Lubis Takeshi Horie Weixing Cao Tatsuhiko Shiraiwa 《Field Crops Research》2008
A number of field trials on rice productivity have demonstrated very high yield, but reported limited information on environmental factors. The objective of this study was to reveal the environmental factors associated with high rice productivity in the subtropical environment of Yunnan, China. We conducted cross-locational field experiments using widely different rice varieties in Yunnan and in temperate environments of Kyoto, Japan in 2002 and 2003. The average daily radiation throughout the growing season was greater at Yunnan (17.1 MJ m−2 day−1 average over 2 years) relative to Kyoto (13.2 MJ m−2 day−1). The average daily temperature throughout the growing season was 24.7 °C at Yunnan, and 23.8 °C at Kyoto. The highest yield (16.5 tonnes ha−1) was achieved by the F1 variety Liangyoupeijiu at Yunnan in 2003, and average yield of all varieties was 33% and 39% higher at Yunnan relative to Kyoto in 2002 and 2003, respectively. There was a close correlation between grain yield and aboveground biomass at maturity, while there was little variation in the harvest index among environments. Large biomass accumulation was mainly caused by intense incident radiation at Yunnan, as there was little difference in crop radiation use efficiency (RUE) between locations. Large leaf area index (LAI) was also suggested to be an important factor. Average nitrogen (N) accumulation over 2 years was 49% higher at Yunnan than at Kyoto, and also contributed to the large biomass accumulation at Yunnan. The treatments of varied N application for Takanari revealed that the ratio of N accumulated at maturity to the amount of fertilized N was significantly higher at Yunnan than at Kyoto, even though there was no great difference in soil fertility. The Takanari plot with high N application showed a N saturation in plant growth at Kyoto, which might be related to low radiation and relatively high temperatures during the mid-growth stage. These results indicate that the high potential yield of irrigated rice in Yunnan is achieved mainly by intense incident solar radiation, which caused the large biomass and the N accumulation. The low nighttime temperature during the mid-growth stage was also suggested to be an important factor for large biomass accumulation and high grain yield at Yunnan. 相似文献
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《Field Crops Research》1998,57(1):85-93
Nitrogen requirements to achieve rice grain yields higher than 13 t ha−1 and the associated internal N-utilization efficiency (NUE) have not been documented. The objective of this study was to compare N accumulation and NUE of irrigated rice in tropical and subtropical environments at yield-potential levels in both climates. Field experiments were conducted in 1995 and 1996 at the International Rice Research Institute, Philippines (IRRI, tropical site), and at Taoyuan Township, Yunnan, China (subtropical site). Three to five high-yielding rice cultivars were grown under optimum crop management. Plants were sampled at key growth stages to determine tissue N concentration, plant N accumulation, N harvest index (NHI), N translocation ratio and NUE. Plant N accumulation at maturity was 19 to 30% greater at Yunnan than at IRRI. Most of this difference resulted from greater N accumulation and N uptake rate during the vegetative period at Yunnan than at IRRI. During reproductive and grain-filling periods, N accumulation and N uptake rate were similar or higher at IRRI than at Yunnan. Grain N concentration at maturity was lower and N translocation ratio from straw to grains during grain filling was higher at Yunnan than at IRRI, and these traits contributed to larger NHI and NUE at Yunnan than at IRRI. Cultivars that produced grain yields over 13 t ha−1 at Yunnan required the accumulation of about 250 kg N ha−1 within the crop and had a NUE of 59 to 64 kg grain per kg plant N. 相似文献
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Tomicus brevipilosus (Eggers) (Coleoptera: Curculionidae, Scolytinae) was recently discovered as a new pest of Yunnan pine (Pinus yunnanensis Franchet) in Yunnan Province in southwestern China. However, little was known on its reproductive biology and pattern of trunk attack on Yunnan pine. The objectives of this study were to better understand the reproductive biology of T. brevipilosus by investigating the seasonality of trunk attacks by parent adults for the purpose of reproduction (i.e., breeding attacks) and the within-tree pattern of these attacks. Our results showed that T. brevipilosus breeding attacks in P. yunnanensis generally started in early March and ended in early June in Anning County, Yunnan. T. brevipilosus exhibited two general patterns of infestation. From early March to mid-April, T. brevipilosus bred preferentially in the trunks of Yunnan pine trees that were already infested by Tomicus yunnanensis Kirkendall and Faccoli and Tomicus minor (Hartig), colonizing spaces along the trunk (mostly in the mid- and lower trunk) that were not already occupied by the other two Tomicus species. Later, from about mid-April to early June, when there were no Yunnan pine trees newly infested by T. yunnanensis and T. minor, T. brevipilosus attacked Yunnan pine by itself, infesting the lower parts of the trunk first and then infesting progressively upward along the trunk into the crown. Infestation by T. brevipilosus extends the total period that P. yunnanensis trees are under attack by Tomicus beetles in southwestern China, which helps explain why Yunnan pine has suffered high levels of tree mortality in recent decades. 相似文献