Single season effects of mixed-species cover crops on tomato health (cultivar Celebrity) in multi-state field trials     

《Applied soil ecology》2014

Cover crop use can help mitigate the deleterious effects of common cropping practices (e.g., tillage) and is, therefore, an important component of soil health maintenance. While known to be beneficial in the long-term, the short-term effects of cover crops, specifically mixed-species cover crops in organic systems are less clear. Cover crop effects on tomato productivity and disease severity were recorded over three field seasons (2010, 2011 and 2012) at sixteen field sites in three states, Maryland, New York and Ohio (MD, NY and OH), each with distinct soilborne disease pressure. Plots of five state-specific cover crop treatments were established the season prior to tomato production; the resulting plant residue was incorporated the following spring approximately four weeks before tomato planting. Total fruit yields along with early-season shoot height and fresh weight were used to compare treatment effects on productivity. Treatment disease severity ratings relied on natural inoculum. Interestingly, the effect of a single season of cover cropping on total yield was significant in no more than 25% of all site years. Similarly, cover crop effects on tomato disease levels were significant in 0–44% of the sixteen field sites. However, significant field-specific patterns were observed in every state across multiple years for some treatments. For example, in New York in 2010, tomato yields following all mixed cover crops were greater than the single rye cover crop in one field, but this pattern was reversed in the adjacent field. Thus, no general recommendation of a specific cover crop mixture can be made for near-term enhancement of tomato productivity or for reduction of disease. Therefore, growers should focus on location and operation-specific variables when choosing cover crops.  相似文献   

Drought Tolerance and Water‐Use Efficiency of Biogas Crops: A Comparison of Cup Plant,Maize and Lucerne‐Grass          下载免费PDF全文

B. Schoo  K. P. Wittich  U. Böttcher  H. Kage  S. Schittenhelm 《Journal of Agronomy and Crop Science》2017,203(2):117-130

The cup plant (Silphium perfoliatum L.) is discussed as an alternative energy crop for biogas production in Germany due to its ecological benefits over continuously grown maize. Moreover, a certain drought tolerance is assumed because of its intensive root growth and the dew water collection by the leaf cups, formed by fused leaf pairs. Therefore, the aim of this study was to estimate evapotranspiration (ET ), water‐use efficiency (WUE ) and the relevance of the leaf cups for the cup plant's water balance in a 2‐year field experiment. Parallel investigations were conducted for the two reference crops maize (high WUE ) and lucerne‐grass (deep and intensive rooting) under rainfed and irrigated conditions. Root system performance was assessed by measuring water depletion at various soil depths. Transpiration‐use efficiency (TUE ) was estimated using a model approach. Averaged over the 2 years, drought‐related above‐ground dry matter reduction was higher for the cup plant (33 %) than for the maize (18 %) and lucerne‐grass (14 %). The WUE of the cup plant (33 kg ha^?1 mm^?1) was significantly lower than for maize (50 kg ha^?1 mm^?1). The cup plant had a lower water uptake capacity than lucerne‐grass. Cup plant dry matter yields as high as those of maize will only be attainable at sites that are well supplied with water, be it through a large soil water reserve, groundwater connection, high rainfall or supplemental irrigation.  相似文献   

新疆兵团设施园艺机械化发展现状及建议   总被引：1，自引：0，他引：1  

张鲁云  杨耀武  郑炫  沈从举 《农机化研究》2015,(5)

新疆兵团设施园艺机械化近年来得到了快速发展,但仍然存在着装备结构不合理、社会服务体系不完善、设施农业技术培训跟不上发展需求等诸多制约因素。为此,根据所收集的资料、数据和实际情况,对兵团设施园艺农业机械化发展现状进行了客观的分析、评价、总结,研究探讨了新形势下新疆兵团设施农业现代化产业结构调整及未来的发展方向,并提出了相应的对策及建议,以促进兵团设施园艺农业的可持续发展。  相似文献   

Evaluation of finger weeder safety and efficacy for intra-row weed removal in irrigated field crops     

Evyatar Asaf  Gal Rozenberg  Itai Shulner  Hanan Eizenberg  Ran Nisim Lati 《Weed Research》2023,63(2):102-114

Increased demand for pesticide-free food and the development of herbicide-resistant weed populations have created a need for non-chemical weed-control tools. A candidate mechanical tool for controlling weeds in the seeding line (intra-row zone) is the finger weeder. This study thus aimed to evaluate the safety and weed-control efficacy of the finger weeder in various irrigated field crops. Eight field trials were conducted in processing tomato, sweet corn, sunflower, cotton, and beetroot over 2 years. The finger weeder treatments were applied as the sole weed-control method (single or double treatments) and in combination with herbicides. A mini meta-analysis was used to evaluate the overall effect of the finger weeder treatments on crop stand and yield and on weed control efficacy. Weed density in the control not treated with herbicides nor a finger weeder ranged between 2 and 62 weeds m⁻². The finger weeder treatments resulted in a significant reduction in weed density, which ranged between 40% and 90%. The weed density following the double finger weeder treatment was not significantly different from that for the conventional herbicide-based treatment (p = 0.32) and could therefore be considered as an effective environmentally friendly alternative. Furthermore, a single FW treatment integrated with herbicide application gave better weed control than the conventional herbicide treatment (p = 0.04). This treatment was safe for the crops with no significant stand (p = 0.19) or yield (p = 0.29) reductions compared to commercial treatment. The results of this study demonstrate the promise of the finger weeder as an effective tool within integrated weed management systems for conventional agro-systems. The tool offers a rational weed-control solution for sustainable systems under irrigation.  相似文献   

四十种瓜菜中超氧化物歧化酶含量测定   总被引：1，自引：0，他引：1  

卢皎  金道山 《华北农学报》1993,8(2):101-104

采用化学发光法测定了40种蔬菜、瓜、果中的超氧化物歧化酶(SOD)的含量,并在此基础上探讨了9种蔬菜中维生素E、C、蛋白对SOD的影响以及它们之间的关系.还观察了蔬菜中SOD的热稳定性.结果表明,不同蔬菜、瓜、果间SOD含量的差异很大,其范围在1.26～176.10×10~(-3)g/g蛋白之间;去除脂溶性维生素E时SOD有不同程度的下降;维生素C及蛋白与SOD无明显对应关系;加热处理后样品的SOD仍得到较好保存.  相似文献   

Cover crop evapotranspiration under semi-arid conditions using FAO dual crop coefficient method with water stress compensation     

G. Bodner  W. Loiskandl 《Agricultural Water Management》2007,93(3):85-98

Cover cropping is a common agro-environmental tool for soil and groundwater protection. In water limited environments, knowledge about additional water extraction by cover crop plants compared to a bare soil is required for a sustainable management strategy. Estimates obtained by the FAO dual crop coefficient method, compared to water balance-based data of actual evapotranspiration, were used to assess the risk of soil water depletion by four cover crop species (phacelia, hairy vetch, rye, mustard) compared to a fallow control. A water stress compensation function was developed for this model to account for additional water uptake from deeper soil layers under dry conditions. The average deviation of modelled cumulative evapotranspiration from the measured values was 1.4% under wet conditions in 2004 and 6.7% under dry conditions in 2005. Water stress compensation was suggested for rye and mustard, improving substantially the model estimates. Dry conditions during full cover crop growth resulted in water losses exceeding fallow by a maximum of +15.8% for rye, while no substantially higher water losses to the atmosphere were found in case of evenly distributed rainfall during the plant vegetation period with evaporation and transpiration concentrated in the upper soil layer. Generally the potential of cover crop induced water storage depletion was limited due to the low evaporative demand when plants achieved maximum growth. These results in a transpiration efficiency being highest for phacelia (5.1 g m⁻² mm⁻¹) and vetch (5.4 g m⁻² mm⁻¹) and substantially lower for rye (2.9 g m⁻² mm⁻¹) and mustard (2.8 g m⁻² mm⁻¹). Taking into account total evapotranspiration losses, mustard performed substantially better. The integration of stress compensation into the FAO crop coefficient approach provided reliable estimates of water losses under dry conditions. Cover crop species reducing the high evaporation potential from a bare soil surface in late summer by a fast canopy coverage during early development stages were considered most suitable in a sustainable cover crop management for water limited environments.  相似文献   

切分蔬菜高压保鲜技术的研究进展及发展对策   总被引：3，自引：0，他引：3  

徐树来  张守勤  刘静波  席军  赵红霞 《农业机械学报》2003,34(2):132-135

切分蔬菜高压保鲜技术是一项高新技术。阐述了高压蔬菜保鲜的意义。介绍了高压蔬菜保鲜的特点、机理、设备及其研究进展，并对该项技术的发展提出了建议。  相似文献   

陇东旱塬农作物生态潜力研究     

杨Rui华  李新文 《甘肃农业大学学报》1993,28(3):256-268

在分析了陇东旱塬什字塬区农业资源的基础上,运用“农业生态区域法”(AEZ)估算了该区主要农作物的资源生产潜力,分析了限制农田生产力的主要因素,提出了进一步挖掘潜力的战略途径.  相似文献   

灌区蓝绿水资源与作物生产水足迹多时空分布量化分析   总被引：2，自引：1，他引：1  

高洁  吴普特  谢朋轩  卓拉 《农业工程学报》2021,37(5):105-112

作物生产水足迹度量作物生产过程对不同类型水资源的消耗,为实现农业水资源管理与评价提供了更全面的新视角。该研究通过耦合土壤水分动态平衡模块,考虑输配水损失,构建灌区蓝、绿水资源与作物生产水足迹多时间尺度分布式量化模型;以宝鸡峡灌区为例,定量评价不同典型年灌区蓝绿水资源与作物生产水足迹多时间尺度演变规律。结果表明:宝鸡峡灌区蓝绿水资源总量在2008-2017年呈上升趋势。各作物对绿水资源利用效率均持续上升,而小麦蓝水资源利用效率呈下降趋势;玉米、小麦生产总水足迹整体呈上升趋势,多年平均值分别为573和779 m3/t;作物生产绿水足迹在拔节-灌浆期占比较高,成熟期占比较低;作物生产水足迹在日尺度波动幅度最大;平水年、丰水年灌区用水存在不合理现象,枯水年作物生产单产水平最高,总水足迹最低,水资源利用效率最高。该研究所构建模型可移植适用于无排水渠系灌区水文模拟,准确量化灌区农业生产耗水,解析日-月尺度作物生产水足迹演变特征,有助于明确灌区作物耗水规律,进而高效利用绿水资源,合理配置蓝水资源,提高作物产量,实现高效生产。  相似文献   

基于轻量型残差网络的自然场景水稻害虫识别   总被引：4，自引：3，他引：1  

鲍文霞  吴德钊  胡根生  梁栋  王年  杨先军 《农业工程学报》2021,37(16):145-152

准确识别水稻害虫对水稻及时采取防护和治理措施具有重要意义,该研究以自然场景中水稻害虫图像为研究对象,针对水稻害虫图像的颜色纹理与背景相近以及同类害虫形态差异较大等特点,设计了一个由特征提取、全局优化以及局部优化模块构成的轻量型残差网络（Light Weight Residual Network,LW-ResNet）用于水稻害虫识别。在特征提取模块通过增加卷积层数以及分支数对残差块进行改进,有效提取自然场景中水稻害虫图像的深层全局特征并使用全局优化模块进行优化;局部优化模块通过设计轻量型注意力子模块关注害虫的局部判别性特征。LW-ResNet网络在特征提取模块减少了残差块的数量,在注意力子模块中采用深度可分离卷积减少了浮点运算量,从而实现了模型的轻量化。试验结果表明,所设计的LW-ResNet网络在13类水稻害虫图像的测试数据集上达到了92.5%的识别准确率,高于VGG16、ResNet、AlexNet等经典卷积神经网络模型,并且LW-ResNet网络的参数量仅为1.62×106个,浮点运算量仅为0.34×109次,低于MobileNetV3轻量级卷积神经网络模型。该研究成果可用于移动端水稻害虫的自动识别。  相似文献