不同光质组合对生菜生长和能量利用效率的影响   总被引：1，自引：0，他引：1  

李列  仝宇欣  李锦 《西北农林科技大学学报(自然科学版)》2020,48(9):114-120

【目的】筛选较优的光质组合,提高人工光植物工厂生菜产量和能量利用效率。【方法】以光强为200μmol/(m~2·s),R/B为4/1的红蓝光(RB)为对照,在光强为150μmol/(m~2·s),R/B为4/1的红蓝背景光基础上,分别添加50μmol/(m~2·s)的绿光(G)、黄光(Y)、橙光(O)和远红光(FR)组成4种不同光质组合处理,分别用RBG、RBY、RBO和RBFR表示,对不同光质组合处理生菜的生长及形态、光合能力、能量利用效率等指标进行比较研究。【结果】RBG、RBO和RBFR处理生菜地上部鲜质量较RB处理分别增加14.5%,14.5%和30.8%,地上部干质量分别增加13.3%,24.1%和29.9%(P0.05)。RBG处理可以增加生菜的株高、总叶面积、净光合速率和能量利用效率。与RB处理相比,RBY处理对生菜的地上部干、鲜质量影响不显著;RBO处理可以提高生菜叶片的光合能力和能量利用效率。RBFR处理可以增加生菜的地上部干、鲜质量,但在实际生产中,生菜叶片较易出现烧尖现象。【结论】RBG和RBO是工光植物工厂生产中较为合适的光质组合。  相似文献   

环境因素和作物生长对稻田CH_4和N_2O排放的影响   总被引：9，自引：3，他引：9  

蒋静艳  黄耀  宗良纲 《农业环境科学学报》2003,22(6):711-714

采用大田试验方法,研究了常规灌溉和持续淹水条件以及不同水平有机质(小麦秸秆)投放量(0、2.25、4.5t@hm-2)条件下各环境因素(包括土壤温度、灌溉水层深度和土壤Eh)对CH4和N2O排放的影响以及水稻生长与CH4排放的关系.结果表明,在2种水分管理下,CH4的累积排放量均与水稻冠层高度呈显著正相关(P<0.001).连续淹水条件下,无论有无外源有机质投放,稻田CH4排放的季节性变化均与土壤温度呈指数相关(P<0.001),而N2O排放的季节性变化则仅取决于土壤水分条件.  相似文献   

祁连山青海云杉林冠层水文功能研究   总被引：11，自引：1，他引：11  

金博文  王金叶  常宗强  葛双兰 《西北林学院学报》2001,16(Z1):39-42

在祁连山水源林生态系统长期定位研究的基础上,利用数理统计原理和数学模型对实测资料进行综合分析,阐述了青海云杉林冠层引起大气降水量变化和质变的水文功能,模拟出了青海云杉林冠截留降水模型.结果表明林内透过雨量随降雨量的增加而增加,二者之间的呈良好的线性关系;在一定的降雨量范围内林冠截留量随降雨量的增加而增加;青海云杉林冠层平均截留降水率为29.4%,它随降雨量和降雨强度的增大而减小,随郁闭度的增加而增大;林冠截留降雨量比降雪量约少10%～30%,实测平均少11.7%;降雨对林冠的淋溶作用使林内透流雨中离子总量比林外雨中增加1倍,因林冠截留而输入林地矿质元素的增加量为61.042 4 kg·hm-2·a-1.  相似文献   

外源褪黑素对生菜根系生长及内源褪黑素含量的影响     

习林杰  王晨雨  严露露  杨俊伟  张静  邹志荣  潘铜华 《北方园艺》2019,(6):7-11

以'韩育'奶油生菜为试材,以清水和乙醇溶液为对照,设置了6个不同的褪黑素浓度(0.01、0.10、1.00、10.00、50.00、100.00μmol·L^-1),研究了根施不同浓度褪黑素溶液对生菜幼苗种子萌发阶段侧根发育、生菜幼苗根系形态、干鲜质量的影响,进一步筛选出最适外源褪黑素浓度(M1)对生菜叶片与根系内源褪黑素含量的影响,以期为褪黑素对植物生长发育的调控作用提供参考依据。结果表明:与对照相比,1.00μmol·L^-1褪黑素处理显著提高了生菜种子萌发阶段侧根数目及生菜幼苗根系的侧根数目和根系的平均直径,降低了根系长度,扩大了根系总表面积。同时,施加褪黑素提高了生菜幼苗的干鲜质量,且该处理下生菜中的褪黑素含量与对照相比提高了9倍。  相似文献   

化学打顶对阿拉尔垦区主栽品种光合冠层的影响     

郭子轩  迪力木热提.伊斯拉木  毛廷勇  李浩  陈国栋 《现代农业科技》2021,(10)

化学打顶是指利用植物生长调节剂来打破作物顶端优势,进而保障作物的正常生长和生产。本文为探究化学打顶对作物的影响,利用摇钱素和棉花打顶剂处理新陆中70和新陆中82不同品种,同时测定不同化学打顶剂处理条件下,棉花的净光合速率、气孔导度、蒸腾速率、胞间CO₂浓度及棉花冠层叶面积指数指标。研究发现：不同化学打顶处理条件下,与人工打顶相比化学打顶的棉花的五种指标变化均不明显,但新陆中70和新陆中82品种的净光合速率平均值与对照相比分别高出3 μmol/(m2.s)和2 μmol/(m2.s),且冠层叶面积指数值比人工打顶的略高。试验结果表明化学打顶处理后没有造成棉花疯长,提高了光能利用率,进而增加作物群体的光合作用。  相似文献   

高产高效栽培下春玉米生育后期冠层结构及其光合特性的研究     

田立双  杨恒山  关艳波  鲍哈斯巴根  张瑞富  毕文波 《上海交通大学学报(农业科学版)》2014,(6):159-164

以郑单958为供试品种,设高产高效栽培(GCGX)和农户传统栽培(CK)2个处理,于2012年和2013年连续2 a进行田间试验,测定春玉米生育后期冠层结构及其光合特性的变化规律。结果表明：吐丝期和乳熟期株高、穗位高产高效栽培略高于农户传统栽培。与农户传统栽培相比,高产高效栽培春玉米叶面积指数较大,在生育期上表现为吐丝之后更为明显,在叶位上表现为棒三叶以下叶片最为突出;不同叶位的叶倾角高产高效栽培显著小于农户传统栽培,而叶向值均显著大于农户传统栽培,在棒三叶表现最为明显;高产高效栽培生育后期净光合速率显著高于农户传统栽培,冠层光合能力极显著高于农户传统栽培。高产高效栽培下春玉米产量为14.009 t·hm^-2(2012)和13.255 t·hm^-2(2013),均极显著高于农户传统栽培。  相似文献   

一种半球图像的处理方法     

张丽敏  王力华  殷红  刘阳 《辽宁林业科技》2006,(3):16-19,36

冠层结构是描述作物植被—环境界面的重要议题,半球图像法以其方便、廉价、省时、省力获得了众多学者的青睐,但半球图像法的发展受到鱼眼镜头畸变和图像处理技术的限制。文章以模拟鱼眼镜头的模型照片为研究对象,应用Image-pro plus图像处理软件,得出从原始图像提取目标的方法步骤,易于理解,方便操作。对照相法研究林冠结构的图像处理方面有一定的指导作用。  相似文献   

Measurement variability in soybean water status and soil‐nutrient extraction in a row spacing study in the U.S. southeastern coastal plain     

《Communications in Soil Science and Plant Analysis》2012,43(9):1111-1134

Abstract

Full‐season determinate soybean [Glycine max (L.) Merrill] was grown in the field in a humid climate for three seasons (1979–81). The objective was to examine variability in several methods of determining basic relationships between soil and plant water status in a range of canopy configurations and to examine treatment effects on soil‐nutrient extraction. In each year, two cultivars, “Davis” (group VI) and “Coker 338” (group VIII) were planted in four row spacings. In 1980 and 1981 the experiment was expanded and split for irrigation and row orientation (N—S or E‐W). Post‐harvest soil samples were collected and analyzed to determine if irrigation, row spacing, or cultivar influenced K, Ca, and Mg extraction patterns.

During the growing seasons, parallel leaf diffusive resistance (R_s) was poorly correlated with xylem pressure potential (ψ_x), canopy s x temperature (T_c), canopy minus air temperature (?T), leaf vapor pressure deficit (LVPD), and atmospheric vapor pressure deficit (VPD) in single factor correlations. Xylem pressure potential was highly correlated with T_c , ?T, VPD, and LVPD, but was poorly correlated with soil water potential. Both ψ_x and T_c were significantly affected by the imposition of shade from a 60% shading cloth within as little as 1 minute of shade imposition. The impact of cultivar on seasonal ψ_x was significant and was nearly half the magnitude of the observed difference caused by irrigation. Irrigation raised ψ_x by only 2.2 bars over the two—year observation period, in spite of large differences in soil water potential when irrigation was imposed. The impact of canopy configuration was not measureable in any water relations parameter except infrared‐determined T_c. Correlation of T and ψ_x was significantly more reliable when limited to a single variety, row spacing, and row orientation. Aspect of infrared temperature measurement also significantly affected observed T_c.

Analysis of post‐harvest soil samples indicated that narrow (50 cm) row spacing in 1980 and irrigation in 1981 significantly decreased post—harvest Mehlich No. I extractable K, but none of the cultural practices influenced extractable Ca or Mg at P(0.05). In 1980, ex‐tractable K within soybean rows was significantly greater than between rows. Similar trends were observed for Ca and Mg in 1980 and for all 3 nutrients in 1981, but those differences were not significant at P(0.05). Overall, these measurements quantify the difficulty in relating soil and plant water status and identifying nutrient extraction patterns in sandy soils within the humid U.S. Southeastern Coastal Plain.  相似文献   

Determination of Moisture Deficit and Heat Stress Tolerance in Corn Using Physiological Measurements and a Low‐Cost Microcontroller‐Based Monitoring System     

H. Kebede  D. K. Fisher  L. D. Young 《Journal of Agronomy and Crop Science》2012,198(2):118-129

In the southern United States, corn production encounters moisture deficit coupled with high‐temperature stress, particularly during the reproductive stage of the plant. In evaluating plants for environmental stress tolerance, it is important to monitor changes in their physical environment under natural conditions, especially when there are multiple stress factors, and integrate this information with their physiological responses. A low‐cost microcontroller‐based monitoring system was developed to automate measurement of canopy, soil and air temperatures, and soil moisture status in field plots. The purpose of this study was to examine how this system, in combination with physiological measurements, could assist in detecting differences among corn genotypes in response to moisture deficit and heat stress. Three commercial hybrids and two inbred germplasm lines were grown in the field under irrigated and non‐irrigated conditions. Leaf water potential, photosynthetic pigments, cell membrane thermostability (CMT) and maximum quantum efficiency of photosystem II (Fv/Fm) were determined on these genotypes under field and greenhouse conditions. Variations observed in air and soil temperatures, and soil moisture in plots of the individual corn genotypes helped explain their differences in canopy temperature (CT), and these variations were reflected in the physiological responses. One of the commercial hybrids, having the lowest CT and the highest CMT, was the most tolerant among the genotypes under moisture deficit and heat stress conditions. These results demonstrated that the low‐cost microcontroller‐based monitoring system, in combination with physiological measurements, was effective in evaluating corn genotypes for drought and heat stress tolerance.  相似文献   

一种改进的树冠截留降雨试验方法     

李铁民 《山西林业科技》2000,(3):19-21

设计了一种基于计算承雨器四周各1m范围内树冠郁闭度，进而通过一次降雨试验可观测到不同郁闭度级林冠截留降雨量的方法，解决了以往林冠截留降雨量测试中林冠疏密和树冠间隙分布不均引起的测量结果误差较大的难题。  相似文献