密度和施肥对旱地马铃薯干物质积累、产量和水肥利用的影响     

柳燕兰  郭贤仕  张绪成  马明生  王宏康 《作物学报》2021,(2):320-331

协同提高产量和资源利用效率,是旱作马铃薯高产高效的基础。本研究以陇薯10号为材料,于2017-2019年进行大田试验,设置当地农民习惯栽培(CK)、高产高效栽培(YE)和超高产栽培(HY)3种栽培模式,测定旱地马铃薯叶面积指数(LAI)、叶片SPAD值、冠层光合能力、干物质积累转运、块茎产量、水肥利用效率等指标。结果表明,与CK相比,YE和HY均提高了马铃薯LAI和叶片SPAD值,YE在降雨较少的2017年增幅更明显;二者均减慢了马铃薯块茎膨大后的LAI和叶片SPAD降低幅度,使其冠层光合能力在块茎膨大期和淀粉积累期2年平均提高29.9%、34.7%和40.2%、50.5%。基于较高的LAI和冠层光合能力,YE和HY的地上干物质在块茎膨大期较CK 3年平均增加123.05%和118.53%;同时块茎膨大后同化物对块茎的贡献率增加22.56%和19.29%,使马铃薯产量在2017-2019年平均增加47.93%和47.78%,水分利用效率平均增加77.59%和75.85%,均达到显著差异水平。YE和HY使马铃薯商品薯产量显著增加,收益显著提高,在2017-2019年分别较CK新增纯收益7330.3元hm^-2和6024.6元hm^-2。较大的群体冠层和较高的物质生产促进了植株对N、P、K的积累,YE的N、P利用效率较CK分别提高15.21%和17.20%,N、K收获指数分别提高3.85%和7.79%;HY的N利用效率提高12.37%。YE的WUE、N和P利用效率较HY提高2.05%、2.53%和23.41%,新增纯收益1305.7元hm-2。因此,YE减施缓释尿素40%并有机替代、密度60,000株hm^-2,能够提高水分和养分利用效率,维持马铃薯花后较高的冠层光合能力,促进茎叶干物质向块茎转运,实现作物增产和资源高效利用协同发展,是半干旱区黑膜覆盖马铃薯种植推荐的高产高效模式。  相似文献   

不同季节露地结球生菜生长模型初探     

孙亚男  刘元军  马铁民  苟党庆 《蔬菜》2021,(6):14-21

为掌握和预测结球生菜生长情况,以露地栽培结球生菜为材料,构建生长模型。通过分析结球生菜的田间表型数据的匹配温度,建立了山东地区春季和秋季露地栽培结球生菜的植株最大直径、株高、叶片数、叶长、叶宽、球高和球宽的生长模型;为了提高田间调查效率,对生长指标间的相关系数进行分析后,确定仅调查植株最大直径、叶长、球高这3项生长指标即可掌握生菜的生长情况。通过日最高温度、日最低温度和生长天数来预测结球生菜生长情况,当预测值与实际值差异高于5%时,需要及时调整种植管理方案,以确保生菜正常生长。  相似文献   

基于综合分段优势的植被覆盖度模型比较     

边慧芹  王雪梅 《草业科学》2021,38(3):432-442

基于Landsat 8 OLI遥感影像选取9种植被指数,与野外实测植被覆盖度进行相关性分析,采用分段方式选择敏感植被指数,构建回归模型及FCD模型(forest canopy density mapping model,FCD)对渭干河–库车河三角洲绿洲植被覆盖度进行反演。结果表明:1)根据实测数据计算不同植被指数在不同植被覆盖度范围内的变化比例,从而确定0.3和0.7作为研究区植被覆盖度的分段点;2)分段回归模型与综合分段优势的FCD模型建模精度均约为79%,但综合分段优势的FCD模型建模集R2较高,RMSE较小,其验证结果优于分段回归模型,验证集R2为0.832,RMSE为0.154,精度为82.018%。综合分段优势的FCD模型更适合用于研究区总体植被覆盖度反演,可为干旱区植被覆盖度定量监测与生态环境评价提供依据。  相似文献   

Improving maize grain yield by formulating plant growth regulator strategies in North China          下载免费PDF全文

Li-sha GONG  Shu-jie QU  Guan-min HUANG  Yu-ling GUO  Ming-cai ZHANG  Zhao-hu LI  Yu-yi ZHOU  Liu-sheng DUAN 《农业科学学报》2021,20(2):622-632

Plant growth regulators(PGRs) are artificially synthesized compounds that have become an important technical guarantee for agricultural production. EDAH(containing 27% ethephon and 3% DA-6) has been proven to inhibit stalk elongation, promote stalk bold and increase mechanical strength and number of vascular bundles. DA-6 could enhance plant photosynthetic capacity and promote cell division and growth. In our study, experiments were performed at summer maize growing season during 2018–2019. The result showed that plant height, ear height and center of gravity height of maize with EDAH+DA-6 treatment were decreased by 10.18, 16.77 and 13.21%, respectively; leaf area and leaf area index also significantly(P0.001) decreased by 24.11 and 60.15%, respectively; the value of mean tilt angle significantly(P0.001) increased by 16.72% compared with the control plants, which meant that EDAH+DA-6 could shape more compact plant type. Therefore, lodging rate of maize with EDAH+DA-6 treatment decreased by 6.95% compared with control plants, and the grain yield was increased by 15.51%. In addition, EDAH+DA-6 treatment significantly improved the quality of maize base stalks, such as improving mechanical properties, which increased maize base stalk crushing strength by 22.23%; increased the hemicellulose, cellulose and lignin contents by 6.93, 3.87 and 30.21%, respectively. In conclusion, EDAH+DA-6 treatment could improve summer maize yield by shaping plant morphological characteristics and group photosynthesis.  相似文献   

不同清洗剂对切割生菜品质的影响   总被引：5，自引：0，他引：5  

周会玲  唐爱均  王祥明 《西北农业学报》2010,19(11):115-118

以次氯酸钠、苯甲酸钠、过氧化氢对切割生菜进行清洗,研究其贮藏过程中品质变化。结果表明:质量分数为0.01%次氯酸钠和质量分数0.5%苯甲酸钠处理能够显著延缓切割生菜叶绿素、Vc以及可溶性固形物含量的下降,保持了较好的感官品质,贮藏到第10天仍有商品价值;体积分数1.0%过氧化氢处理对保持切割生菜的品质有一定的作用,但处理效果略次于苯甲酸钠和次氯酸钠,贮藏6 d后,感官品质和Vc损失较多。  相似文献   

夏玉米光谱特征对其不同色素含量的响应差异   总被引：1，自引：0，他引：1  

张俊华  张佳宝 《西北农业学报》2010,19(4):70-76

在不同施氮水平夏玉米的6个典型生育期,采用化学方法测定冠层叶绿素含量,利用叶绿素计测定的叶绿素读数以及光谱反射率,系统分析了单波段反射率、可见光和近红外波段组合而成的归一化植被指数(NDVI)、比值植被指数(RVI)等8种常见植被指数与相应时期2种方法测定的叶绿素含量的相关性。结果表明,随着施氮量的增加,叶绿素含量和冠层近红外波段反射率都随之增加;整个生育期中孕穗期在近红外区域反射率最高,与可见光波段反射率相差最大;6个生育期单波段510~1 100 nm反射率、NDVI、RVI等植被指数与叶绿素含量的2种测定结果显著相关或极显著相关,植被指数的表现较单波段更好,且从苗期到乳熟期,各波段反射率与叶绿素的相关性逐渐增强。整体来讲,可见光中560、660 nm和近红外760、810、590和1 300 nm组合的NDVI在各生育期与2个农学指标的相关性较好,选择NDVI(560,760)可以准确拟合夏玉米叶片叶绿素含量,其对化学方法测定的叶绿素含量拟合效果较佳。  相似文献   

蓄冷剂在油麦菜保鲜中的应用研究   总被引：8，自引：0，他引：8  

高凯  张娜  杨秀茹  张平 《保鲜与加工》2010,10(3):30-32

以4％氯化钠水溶液和蒸馏水作为蓄冷介质,采用二种不同的介质载体,利用蓄冷剂的相变潜热来维持低温．探讨其在油麦菜贮藏保鲜中的应用效果。试验结果表明,应用蓄冷剂可以延长泡沫箱内油麦菜的保冷时间,提高贮藏保鲜效果;其中以吸水海绵一蒸馏水系统保鲜效果最佳;盐蓄冷剂没有显示出比冰蓄冷剂优越的保冷效果。  相似文献   

Within-Canopy Distribution of Stenoma catenifer (Lepidoptera: Elachistidae) Infestation in Avocado Orchards     

Alessandra M Vacari  Felipe Damato  Bruno Gomes Dami  Mateus Levi Feliz de Lima  Lucas S M Ubiali Lima  Gustavo Pincerato Figueiredo  Eder de Oliveira Cabral  Cesar Rodriguez-Saona 《Journal of insect science (Online)》2021,21(5)

Native to the neotropics, the avocado seed moth Stenoma catenifer Walsingham (Lepidoptera: Elachistidae) is a specialist pest of the family Lauraceae and considered one of the most important pests of avocados worldwide. However, little is known regarding its spatial distribution within a single tree. Therefore, we designed a study to evaluate the effects of canopy height and aspect (i.e., side of the tree) on fruit infestation by S. catenifer larvae in avocados. The study was conducted in three commercial organic avocado orchards located in São Paulo, Brazil. At each orchard, 40 fruit from 30 random trees were sampled weekly from October 2017 through February 2018, evaluating the number of fruits infested by S. catenifer larvae at three tree heights (bottom, middle, and top). In addition, fruits on the ground were also sampled. We also evaluated the effect of the side of the tree where the fruits were collected, i.e., whether they were on the side facing the east (sunrise) or the west (sunset). Within the avocado canopy, the level of fruit infestation by S. catenifer larvae was significantly higher at the top of the trees than in the middle and bottom. Fruit on the ground had lower levels of infestation than those on the tree canopy. The level of fruit infestation was also higher on the side of avocado trees facing the east (sunrise). Understanding the within-tree distribution of S. catenifer will help to better target monitoring and control activities against this pest in avocados.  相似文献   

人工毛竹林水文生态功能的初步研究   总被引：2，自引：0，他引：2       下载免费PDF全文

孔维健  周本智  安艳飞  王刚  王小明  徐升华 《林业科学研究》2010,23(5):713-718

在2009年3—10月对浙江庙山坞自然保护区人工毛竹林的水文生态特征进行了定位样地和径流场观测研究,以探讨其林内降水分配规律和水土保持功能。结果表明:(1)观测期内,林外总降水量达1 220.8 mm,穿透雨量、茎流量、林冠截留量分别占总降水量的78.2%、7.3%和14.5%。随着林外降水量的增加,穿透雨量、茎流量呈线性增加,而林冠截留量先是迅速增加,当林外降水量达10 mm后增速减缓,并趋于稳定(5 - 6 mm)。(2)人工毛竹林林地凋落物现存量平均为4.37 t·hm^-2,最  相似文献   

杭州湾北岸沿海防护林冠层结构及林下光环境     

成向荣  冯利  虞木奎  刘志龙  张翠  王宗星  葛乐 《浙江林学院学报》2010,27(6):872-876

利用跟踪辐射与冠层结构测量仪（TRAC）研究了杭州湾北岸6种沿海防护林冠层结构及林下光环境特征。结果表明：6种林分以中山杉Taxodium ascendens × mucronatum间隙分数最大,红叶椿Ailanthus altissima ‘Hongye’,洋白蜡Fraxinus pennsylvanica和美国皂荚Gleditsia triacanthos的平均间隙分数接近,乌桕Sapium sebiferum和女贞Ligustrum lucidum的平均间隙分数相对较小。而各林分叶面积指数特征与间隙分数相反,女贞和乌桕平均叶面积指数（LAI）较高,红叶椿、洋白蜡、美国皂荚和中山杉的叶面积指数接近。红叶椿叶丛生效应较低,而美国皂荚、乌桕、中山杉、洋白蜡和女贞具有类似的丛生效应。各林分内光量子通量密度（PPFD）具有较大差异,其大小依次为中山杉＞美国皂荚＞红叶椿,洋白蜡＞乌桕＞女贞。图2表4参18  相似文献