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正近段时间,不少农户发来棉苗感病的照片,询问棉花得的什么病?有的问是不是红叶茎枯病,有的问是不是茎枯病?或者问两者之间有何不同?为了防止诊断预防失误,我们应加以鉴别。实际上,这两种病害是完全不同的。一是茎枯病是真菌性病害,红叶茎枯病是生理性病害;二是茎枯病发生在苗、蕾期,以苗期为甚,红叶茎枯病发生在开花结铃期;三是苗期高温之后转低温阴雨天气易诱发茎枯病,红叶茎枯病是在长期高温干旱之后陡降大到暴雨易诱发的;四是茎枯病局部点片发生的,严重的棉花幼苗枯死,红叶茎枯病 相似文献
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棉花是滨州市的主要经济作物,常年种植面积在13.3万hm2左右,近年来随着转基因抗虫棉的大量种植,棉田的病虫害发生了一些变化,抗虫棉对棉铃虫等鳞翅目害虫表现出优良的抗虫性,但其抗病性均较差,特别是在棉花生长的中后期,多种病害的发生严重影响了棉花的产量和品质。1病害的种类根据调查,在本市棉田中后期发生的主要病害有枯萎病、黄萎病、红叶茎枯病、褐斑病、轮纹病、角斑病、棉铃疫病、棉铃炭疽病、棉铃红腐病等,为害比较重的有枯萎病、黄萎病、红叶茎枯病、棉铃疫病、棉铃炭疽病、棉铃红腐病。2主要病虫害的为害症状及发病规律2.1棉花枯… 相似文献
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棉花红叶茎枯病又称红叶枯病或凋枯病,是严重为害棉花的一种生理性病害。发病后,棉株中下部叶片变暗变厚,皱缩发脆,叶脉间出现黄色斑点,叶缘卷缩,叶片逐渐变黄或变红,后期叶片干枯脱落;侧根短、少,根系不发达;上层棉桃坐不住,中层桃小、桃瘪,衣分低,吐絮不畅,严重影响棉花产量、品质及经济效益。据调查,该病多发生在土壤速效钾含量较低、质地偏轻和土壤结构不良的田块。据研究表明,在不良环境下,棉株缺钾,抗逆能力变差是其发生的主要原因,另外还有气候环境不适,土壤水分、养分和通气失调等原因。 相似文献
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红叶早衰是新疆棉花常见的一种生理性病害,常因田间管理不当而引起。本文简要介绍了2011年库尔勒垦区棉花红叶枯病的发生原因及预防措施。 相似文献
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基于光谱红边参数的棉花黄萎病叶片氮素含量诊断研究 总被引:1,自引:0,他引:1
以黄萎病胁迫下棉花叶片为供试材料,分析了黄萎病棉叶氮素含量(LNC)与光谱红边参数间的关系,建立了黄萎病棉叶LNC(Leaf nitrogen content) 的光谱红边参数诊断模型。结果表明:(1) 随着黄萎病严重程度的增加,棉叶LNC逐渐减小,且差异显著;(2)黄萎病棉叶红边参数红边位置(REP) 、红边振幅(Dr)、红谷位置(Lo) 、红边深度(Depth672)和红边面积(Area672) 均减小,红边宽度(Lwidth) 增加,且Area672的值减小的幅度最大,Dr减小的幅度最小,Lwidth的值增加的幅度较大; (3) 黄萎病棉叶LNC含量均与红边参数REP、Lo、Depth672和Area672呈极显著正相关,与Lwidth呈极显著负相关,与Dr未达显著相关;(4)基于红边参数建立的黄萎病棉叶LNC含量的诊断模型均达到极显著水平(P<0.01),其中以Area672为自变量建立的黄萎病棉叶LNC的诊断模型的精度最高,R2超过0.7,RMSE小于0.6,RE小于0.007,能很好地诊断黄萎病棉叶LNC。 相似文献
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Chen Bing Wang Jing Li Tiannan Lin Hai Hang Huanyong Wang Fangyong Wang Qiong Ma Qi 《棉花学报》2017,29(6):570
[Objective] The purpose of this study was to determine the change of microstructure and photosynthetic characteristics in cotton leaves under different disease index levels (b0~b4).[Method] Through investigation and sampling in cotton fields, five treatments were designed based on disease index levels of cotton leaf, and the leaf photosynthesis was tested by WFS-3000 and microstructure was observed with Microscope ECLIPSE Ni-E. [Result] With the increase in disease index levels, cotton leaf gradually lost green color, serious necrosis area occurred, with the leaf withered up till dried to death. The stomata of disease leaf incurred abnormally, increasing intercellular space in mesophyll tissue. Total thickness, upper and lower epidermis thickness, palisade tissue thickness and spongy tissue thickness all decreased significantly among all treatments; the trend showed as followed: total thickness was b0>b1>b2>b3>b4, upper epidermis thickness was b0>b1>b2>b3, lower epidermis thickness, palisade and spongy tissue thickness were consistent as b0>b1>b2. As a whole leaf of total thickness, upper, lower epidermis thickness, palisade and spongy tissue thickness were very significantly negatively correlated with leaf disease index levels, The correlation coefficient reached -0.6. The net photosynthesis rate, transpiration rate, stomata conductance gradually decreased and reached significant different with b0, leaf temperature increased, internal CO2 first went up then down but no significant difference with b0. [Conclusion] The results indicated that Verticillum wilt damaged leaf microstructure and impaired photosynthesis of cotton leaf. 相似文献
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不同遗传型棉花品种光谱反射特性研究 总被引:14,自引:4,他引:10
不同遗传型棉花品种有不同的光谱反射特性,黄叶棉在可见光区的反射率最高,红叶棉最低,绿叶棉居中,绿叶鸡脚叶与普通叶无明显差异;黄叶棉和绿叶棉在可见光区的反射峰在560nm处,而红叶棉在610nm处;近红外反射率可在一定程度上反映棉花群体大小的差异。 相似文献
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翻耕深度对膜下滴灌棉花农艺性状及产量的影响研究 总被引:2,自引:1,他引:1
为了探明翻耕深度对新疆膜下滴灌棉花生长的影响,通过设置3个翻耕深度(10 cm、30 cm和50 cm )处理,研究不同翻耕深度对棉花农艺性状及产量构成的影响。结果表明,翻耕深度对棉花生育进程影响显著,翻耕30 cm和50 cm分别比翻耕10 cm全生育期延长20天和25天。同时翻耕深度增加使棉花株高、果枝数、主茎叶片数和单株铃数均显著增加,LAI增大。翻耕深度增加,棉花中、下部结铃比例减小,上部铃比例显著增加,同时皮棉产量显著增加,翻耕30 cm比10 cm增加52.9%,翻耕50 cm比30 cm增加9.2%。而收获株数和单株结铃数增加是皮棉产量提高的主要原因。综合分析认为,深翻耕有利于连作棉田棉花生长及产量水平提高。 相似文献
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杂交棉叶枝数量对产量的贡献规律机理研究 总被引:1,自引:0,他引:1
通过对转基因抗虫杂交棉保留不同数量叶枝、设置不同密度处理,研究发现,随着叶枝数量增多,单个叶枝籽棉产量占单株籽棉总产的比例降低,留2叶枝处理单叶枝籽棉产量占16%左右,留3叶枝处理占12%左右,留4个叶枝处理占9%左右.同一叶枝数处理中,叶枝之间籽棉产量无显著差别.同时,随叶枝数量的增加,单个叶枝叶面积占单株总叶面积比例减少,留2叶枝处理中单个叶枝叶面积比例占20%左右,留3叶枝处理占15%左右,留4个叶枝处理占13%左右.叶枝铃数占单株总铃数比例也有减少趋势,留2叶枝处理中单叶枝占20%,留3叶枝占15%,留4叶枝占13%,且同一叶枝处理中,各叶枝比例差别不显著.而叶枝的数量对主茎叶和叶枝中叶绿素8的含量无显著影响. 相似文献
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华北平原地区棉花叶片SPAD光谱特征有待探明,其最适宜建模方法亦有待研究。笔者针对华北平原棉区,基于无人机多光谱探索其叶片SPAD光谱特征和最佳建模方法。以德州市夏津县大李庄棉区为研究区,利用无人机获取棉花花铃期的多光谱图像,同步测定棉花叶片SPAD值;对原始光谱进行预处理并组合构建光谱指数,进而采用相关分析筛选出6个棉花SPAD特征光谱指数;分别采用BP神经网络(BPNN)、多元逐步回归(MSR)和支持向量机(SVM)方法构建棉花SPAD值定量分析模型,并对模型验证、对比,优选最佳模型和建模方法,进而定量分析研究区棉花叶片SPAD空间分布。结果表明:棉花叶片SPAD的特征波段为红光和红边波段;入选模型的特征光谱指数为r、r*reg、(reg-r)/(reg+r)、r-g、r/g、$\sqrt{r^{2}+g^{2}}$;对比3种建模方法,BPNN模型精度最高,其建模集R2、RMSE分别为0.747、4.568,验证集R2、RMSE、RPD分别为0.758、4.142、2.135,确定为棉花叶片SPAD的最佳模型。基于BP神经网络模型进行棉花叶片SPAD的空间分布反演,反演值与实测值具有高度一致性,拟合结果较好。BP神经网络可以作为基于无人机多光谱的华北平原棉花叶片SPAD建模的优选方法,该研究可促进棉田定量遥感和棉花长势监测。 相似文献
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[Object] To setup the hyperspectral sensing models for estimating SPAD value of cotton leaves under waterlogging stress. [Method] Irrigation and drainage controllable plots were introduced to simulate the waterlogging stress treatment in the flowering and boll forming stage, during which the change characteristics of the cotton leaf spectral reflectance and SPAD value were observed after 1 d, 3 d, 6 d, 9 d waterlogging, respectively. To find out the hyperspectral sensing models for estimating SPAD value of cotton leaves under waterlogging stress, the correlation and regression relationships between SPAD value and spectrum parameters were analyzed. [Result] (1) The SPAD value of the fourth cotton leaf from the top was significantly lower than control when suffers from waterlogging for 3 d, when waterlogged 9 d the SPAD value decreased by around 15% compared with the control. (2) The cotton suffering from waterlogged damage in the flowering and boll forming stage caused the reflection peak in green light wave band became steep, while the near infrared spectral reflectance increased, and caused the reduction of red absorption and red edge position "blue shifts", the red edge position drifts towards short wave with 4~5 nm when suffers from waterlogging for 9 d. With increase of the waterlogged days, the red edge slope and red edge area increased with a maximum value at 6 d of waterlogging, meanwhile, the skewness and kurtosis of red edge increased. (3) After waterlogging, the SPAD value of the fourth cotton leaf from the top (chlorophyll content) had a remarkable correlation with red edge slope(Dr), red edge position(λr), green peak reflection(Rg), green peak position(λg), red well position(λo), blue edge area(SDb), yellow edge skewness(Sy), yellow edge kurtosis(Ky), red edge skewness(Sr), red edge kurtosis(Kr), etc. An experience linear, polynomial and exponential models for estimating SPAD value had been built through using the Sy, Sr, Kr as independent variables, respectively, their determination coefficient (R2) were greater than 0.9, and the root mean square error (RMSE) were less than 1; and an experience binary linear regression equation for estimating SPAD value had been built through multivariate regression using the λg, SDr/SDb(VI3), Sb, Sy, Ky as independent variables, the R2 was as high as 0.973, and the RMSE was 0.393. [Conclusion] The model can be remote sensing model used as estimating leaf SPAD of cotton value under waterlogging stress. 相似文献
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为了研究现有的一些棉花品种是否抗斜纹夜蛾与棉大卷叶螟,以及哪些性状与抗性有关。在2007、2009、2010年斜纹夜蛾与棉大卷叶螟发生较重的年份,调查了田间自然虫源下各品种的虫害发生情况以及棉花的一些农艺性状。结果表明,不同品种对斜纹夜蛾和棉大卷叶螟的抗性差异很大;斜纹夜蛾对转Bt基因棉花没有选择性,长势强、茎杆与叶片茸毛密的棉花斜纹夜蛾发生少,斜纹夜蛾喜食无腺体棉花;转Bt基因棉对棉大卷叶螟有较好的抗性,群体长势弱、茎杆细的棉花不抗棉大卷叶螟,鸡脚叶、亚红叶的棉花对棉大卷叶螟的抗性好于其它类型的棉花。抗虫性与诸多性状有关,性状之间的互作也起较大作用,近等基因系是抗虫性研究的最好材料。 相似文献