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Effects of planting methods on yield and quality of different types of japonica rice in northern Jiangsu plain, China 被引量:16
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作者 BIAN Jin-long XU Fang-fu +5 位作者 HAN Chao QIU Shi GE Jia-lin XU Jing ZHANG Hong-cheng WEI Hai-yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第12期2624-2635,共12页
Mechanical transplanting with carpet seedlings(MC) and mechanical direct seeding(MD) are newly developed planting methods, which increase in popularity and planted area each year. Knowing the difference for yield and ... Mechanical transplanting with carpet seedlings(MC) and mechanical direct seeding(MD) are newly developed planting methods, which increase in popularity and planted area each year. Knowing the difference for yield and rice quality under different planting methods is of great importance for the development of high quality and yield cultivation techniques under mechanical conditions. Therefore, three kinds of japonica rice including hybrid japonica rice, inbreed japonica rice, and soft rice were adopted as materials. And the differences in the quality of processing, appearance, cooking and eating quality, nutrition, and the rapid viscosity analyzer(RVA) profile were studied to reveal the effects of planting methods on yield and quality of different types of japonica rice. Results showed that the milled rice and head rice rates under MC was significantly higher than those under MD, and the processing quality of inbreed japonica rice was the most stable. Compared with MC, length/width ratio of rice under MD was significantly increased, and chalkiness rate, size, and degree were significantly decreased. The protein content under MD was lower than that under MC. MC showed higher peak viscosity and breakdown value than MD. The taste value was the greatest for soft rice, followed by inbreed japonica rice, and then by japonica hybrid rice, with no significant differences resulting from planting methods. Compared with MC, MD significantly improved the appearance quality, though processing quality and nutritional quality were decreased. And there was no significant difference in cooking and eating quality between MC and MD. Under different planting methods, the appearance quality of inbreed japonica rice changed the most and the processing quality was the most stable. The nutritional, cooking and eating quality of soft rice changed the least. Therefore, according to the different planting methods and market needs, selecting the appropriate rice varieties can reduce the risks in rice production and achieve good rice quality. 展开更多
关键词 hybrid japonica rice inbreed japonica rice soft rice planting method rice quality
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Comparison of yield traits in rice among three mechanized planting methods in a rice-wheat rotation system 被引量:15
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作者 XING Zhi-peng HU Ya-jie +8 位作者 QIAN Hai-jun CAO Wei-wei GUO Bao-wei WEI Hai-yan XU Ke HUO Zhong-yang ZHOU Gui-sheng DAI Qi-gen ZHANG Hong-cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第7期1451-1466,共16页
Understanding the differences in yield traits of rice among pothole seedling of mechanical transplanting (PSMT), carpet seedling of mechanical transplanting (CSMT) and mechanical direct seeding (MDS) is of great... Understanding the differences in yield traits of rice among pothole seedling of mechanical transplanting (PSMT), carpet seedling of mechanical transplanting (CSMT) and mechanical direct seeding (MDS) is of great importance not only for rice scientists but also for rice farmers to develop a high-yield production system under mechanical conditions in a rice-wheat rotation system. However, such traits are yet to be studied among rice varieties ofjaponica-indica hybrid rice (JIHR),japonica conventional rice (JCR) and indica hybrid rice (IHR). Field experiments were conducted in 2014 and 2015, where six cultivars of the three rice types JIHR, JCR and IHR were grown individually with PSMT, CSMT and MDS methods, under respective managements for each method to achieve the maximum attainable yield. Results showed that (i) the PSMT significantly increased grain yield of JIHR by 22.0 and 7.1%, of JCR by 15.6 and 3.7% and of I HR by 22.5 and 7.4%, compared to MDS and CSMT on average across the two years, respectively. The highest yield was produced by the combination of JIHR and PSMT; (ii) high yield under PSMT was mainly attributed to large sink capacity and high-efficient dry matter accumulation. With sufficient panicles per hectare, the increase of spikelet number per panicle, especially the increase in spikelet number of the secondary rachis-branches was determined to be the optimal approach for developing a large sink capacity for rice under PSMT. The optimal tillers development, large leaf area index at heading stage, and high leaf area duration, crop growth rate and net assimilation rate during grain-filling phase could be the cause of sufficient dry matter accumulation for rice under PSMT; (iii) moreover, the PSMT favored plant growth as well as enriched the stems plus sheaths during grain-filling phase, as compared with CSMT and MDS. These results suggest that PSMT may be an alternative approach to increasing grain yield in a rice-wheat rotation system in the lower reaches of the Yangtze River in China. 展开更多
关键词 RICE grain yield mechanized planting method pothole seedling of mechanical transplanting
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Temperature and solar radiation utilization of rice for yield formation with different mechanized planting methods in the lower reaches of the Yangtze River,China 被引量:9
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作者 XING Zhi-peng WU Pei +8 位作者 ZHU Ming QIAN Hai-jun HU Ya-jie GUO Bao-wei WEI Hai-yan XU Ke HUO Zhong-yang DAI Qi-gen ZHANG Hong-cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第9期1923-1935,共13页
Several studies have demonstrated the effect of planting methods on rice yield, but information on the climate resources is limited. This study aims to reveal the effects of planting methods on climate resources assoc... Several studies have demonstrated the effect of planting methods on rice yield, but information on the climate resources is limited. This study aims to reveal the effects of planting methods on climate resources associated with rice yield in a rice-wheat rotation system in the lower reaches of the Yangtze River, China. Field experiments were conducted in 2014 and 2015 with two japonica, two indica hybrid, and two japonica-indica hybrid varieties grown under three mechanized planting methods: carpet seedling of mechanical transplanting(CT), mechanical direct seeding(DS), and pot-hole seedling of mechanical transplanting(PT). The rice yield and total dry matter under PT were greater than those under CT and DS methods. Besides, the entire growth duration and daily production showed significant positive relations with rice yield. Compared with CT and DS, the effective accumulated temperature and cumulative solar radiation of rice under PT were higher in phenological phases. In addition, the dry matter/effective accumulated temperature and solar energy utilization of rice under CT and DS were higher during vegetative phase and lower during reproductive and grain filling phases in contrast to PT. The mean daily temperature and mean daily solar radiation in the entire growth duration showed significant positive correlation with rice yield, total dry matter, and harvest index. This study demonstrated that when the mean daily temperature is 〈25.1°C in vegetative phase and 〉20.1°C in grain filling phase, rice yield could be increased by selecting mechanized planting methods. Most varieties under PT method exhibited high yield and climate resources use efficiency compared with CT and DS. In conclusion, the PT method could be a better cultivation measure for high rice yield, accompanied with high temperature and solar radiation use efficiency in a rice-wheat rotation system in the lower reaches of the Yangtze River, China. 展开更多
关键词 rice mechanized planting methods temperature solar radiation
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Development of 2BZJ-3/4 Precision Planter for Soybean Narrow-row flatdense Planting Method 被引量:2
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作者 XIANG Dexiang CHEN Haitao JI Wenyi 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第3期43-47,共5页
Based on the study on cultivation models of soybean narrow-row-flat-dense planting under the conditions of different between-row spacing and inter-plant spacing by using the comparison field experiment, and technical ... Based on the study on cultivation models of soybean narrow-row-flat-dense planting under the conditions of different between-row spacing and inter-plant spacing by using the comparison field experiment, and technical studies of the contour following the seeder unit, the anti-block, the lateral and stratified the deep fertilizing, according to the design ideas of planting units integration and variable between-row spacing from 30 to 45 cm, the 2BZJ-3/4 precision planter matched with 18-32 hp tractors has been developed for the popularization of the narrow-row-flat-dense planting soybean technique by means of Virtual Prototyping (VP) technology. 展开更多
关键词 SOYBEAN narrow-row-flat-dense planting method plantER VP technology
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Effects of Planting Methods on Root Yield and Nutrient Removal of Five Cassava Cultivars Planted in Late Rainy Season in Northeastern Thailand 被引量:1
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作者 Anan Polthanee Kitti Wongpichet 《Agricultural Sciences》 2017年第1期33-45,共13页
The objectives of this study were to evaluate growth, yield and nutrients removal of five cassava cultivars planted by different planting methods in late rainy season of northeastern Thailand. A split plot design was ... The objectives of this study were to evaluate growth, yield and nutrients removal of five cassava cultivars planted by different planting methods in late rainy season of northeastern Thailand. A split plot design was used in this study. The planting methods (vertical and horizontal) were assigned as main-plots. Cassava cultivars (Rayong-7, Rayong-11, Rayong-72, Huaybong-80 and E-dum) were assigned as sub-plots with four replications. Results showed that vertical planting gave significantly higher fresh storage root yield than those of horizontal planting, across five cassava cultivars. The cultivar Rayong-7 produced maximum fresh storage root yield across two planting methods, but not significantly different from Rayong 11, Huaybong 80 and Edum cultivars. Irrespective of nutrient removal, N, P and K removed ranges from 2.9 - 3.6, 0.8 - 1.3 and 5.3 - 7.9 kg per ton fresh root weight, respectively depending on cassava cultivar. The cultivar Rayong-7 removed the highest quantities of N, and the cultivar Rayong-11 removed maximum of P and K in the present study. Regardless of nutrient removal at different plant parts;N, P and K removed maximum quantities in leaf, stem and storage root, respectively. Planting method had no significant effect on N and P removal, but significant effect on K removal. The vertical planting removed K higher than those of horizontal planting. 展开更多
关键词 CASSAVA CULTIVAR plantING method Root Yield NUTRIENT Removal Drought
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Effects of Planting Methods and Seed Density on Vegetable Yield and Nutrient Composition of <i>Solanum macrocarpon</i>and <i>Solanum scabrum</i>in Southwest Nigeria 被引量:1
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作者 Mary K. Idowu Durodoluwa J. Oyedele +2 位作者 Ojo Kolawole Adekunle Oluwole Olalekan Akinremi Bob Eilers 《Food and Nutrition Sciences》 2014年第13期1185-1195,共11页
Two field studies were carried out using Solanum macrocarpon and Solanum scabrum to investigate the effects of planting methods and seed density required for optimum biomass yield and nutrient content in southwest Nig... Two field studies were carried out using Solanum macrocarpon and Solanum scabrum to investigate the effects of planting methods and seed density required for optimum biomass yield and nutrient content in southwest Nigeria. Two planting methods (drilling and broadcasting), and two seed densities (4 and 8 table spoon full) were investigated as a 2×2×3 factorial experiment in randomized complete block design and replicated three times. Four seed spoons gave 25.78 kg seeds ha-1 for S. macrocarpon and 20.67 kg·seeds·ha-1 for S. scabrum. Significant highest S. macrocarpon shoots (2.75 kg·m-2) and Ca, K, Fe and Zn contents and S. scabrum (2.95 kg·m-2) and Zn content, were obtained with drilling and four spoons of seeds compared with broadcasting and 8 spoons of seeds. This treatment gave average values for N, P, K, Mg, Ca, Na, Fe, Zn, Mn, Cu, Ca/P and Na/K ratio were 2.79%, 0.03%, 3.37%, 1.64%, 0.02%, 300 mg·kg-1, 100 mg·kg-1, 300 mg·kg-1, 8 mg·kg-1, 1.22 and 0.008 for S. macrocarpon and 2.05%, 0.27%, 5.81%, 3.27%, 2.91%, 0.09%, 280 mg·kg-1, 52.99 mg·kg-1, 359.35 mg·kg-1 and 22.42 mg·kg-1, 11.63 and 0.016 for S. scabrum. It was concluded that planting in drilling made weeding, fertilizer application, irrigation and harvesting more effective rather than by broadcasting, and four spoons of seeds per 9 m-2 produced deep green and broader leaves and balanced nutrient contents than eight spoons of seeds. 展开更多
关键词 SOLANUM macrocarpon SOLANUM scabrum plantING method Seed Density and NUTRIENT Contents
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Improving Grain Yield of Indigenous Rice in Tidal Floodplain of Southern Bangladesh: Effect of Seedling Age and Transplanting Method 被引量:1
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作者 Abdul Hamid Md. Jafar Ullah +2 位作者 Md. Moynul Haque Md. Faruque H. Mollah Md. Moksedur Rahman 《Agricultural Sciences》 2015年第12期1538-1546,共9页
Rice production in the tidal floodplain of southern Bangladesh is constrained by uncontrolled water. In absence of high yielding varieties suitable for tidal floodplain, farmers grow low yielding indigenous cultivars ... Rice production in the tidal floodplain of southern Bangladesh is constrained by uncontrolled water. In absence of high yielding varieties suitable for tidal floodplain, farmers grow low yielding indigenous cultivars of tall plant type. This paper reports the effect of agronomic management on the yield and yield components of an indigenous rice cultivar, Sadamota. The trial was conducted in 10 farmers’ plots located widely apart in two upazila (sub-districts)—Jhalakati and Rajapur. 45 d and 60 d old seedlings were transplanted either in rows at 40 cm × 20 cm spacing or following farmers’ traditional practice of random planting. Transplanting 60 d old seedlings produced 14% higher yield compared with 45 d old seedlings. Transplanting in rows also increased grain yield by 12%. The yield increase was associated with hill density, the number of effective tillers per hill and the number of spikelets per panicle. 展开更多
关键词 RICE SEEDLING Age planting method TIDAL FLOODPLAIN TILLERS SEEDLING Dry Weight Grain Yield
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Comparison of Wheat Planting Methods and Residue Incorporation Under Saline-Sodic Soil
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作者 Muhammad Arshadullah Massomma Hassan Arshad Ali Syed Ishtiaq Hyder 《Journal of Life Sciences》 2011年第12期1042-1045,共4页
The present research was conducted to monitor the wheat productivity along with residue incorporation under saline-sodic soils by examining different planting methods at Zaidi Farm, Kakar Gill, Sheikhupura District, P... The present research was conducted to monitor the wheat productivity along with residue incorporation under saline-sodic soils by examining different planting methods at Zaidi Farm, Kakar Gill, Sheikhupura District, Punjab Province in 2007-2008. Randomized Complete Block Design (RCBD) with three replications was used having treatments: control (broadcast), zero till wheat plantation, wheat plantation using happy seeder and wheat plantation on raised beds. It was observed that tillering was pretty higher (141 and 139 m2) under raised bed as well as happy seeder plantation as compared to zero tilled wheat and broadcast technique. A significant relation was detected among maximum straw and grain yield (4,898 and 1,752 kg-ha1) in raised bed followed by happy seeder planting method. The lowest grain yield was recorded in the broadcast method. Maximum net revenue earned by raised bed planting method (39,908 PKR) followed by happy seeder methodology (37,533 PKR). The overall study suggests that raised bed and happy seeder wheat plantation are the superior planting methods. 展开更多
关键词 WHEAT planting methods crop residue saline-sodic.
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Bamboo (Bambusa vulgaris) Regeneration by Cuttings: Comparative Study of Planting Methods of Culm Cuttings at UR-CAVM Busogo Campus Tree Nursery
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作者 Jean Nduwamungu 《Journal of Health Science》 2018年第1期42-48,共7页
Bamboo is one of the fastest growing and highest yielding renewable resources with multiple uses in the world. Lack of seedlings in sufficient number has generally been a major constraint in establishing more bamboo p... Bamboo is one of the fastest growing and highest yielding renewable resources with multiple uses in the world. Lack of seedlings in sufficient number has generally been a major constraint in establishing more bamboo plantations. This study investigated the efficiency of regenerating Bambusa vulgaris through cuttings at Busogo sector, Musanze district, using vertical and horizontal methods with and without water treatment. The experiment consisted in a RCBD (Randomized Complete Block Design) with 4 replications. The growth and sprouting of the 64 cuttings were monitored for three months and 18 days (105 days). In terms of planting method, horizontal planting method showed best sprouting percentage of 68%. In terms of treatment used, horizontal planting method without using water treatment showed slightly better sprouting percentage of 60%. The results further show that about 87% of sprouts had between 0 and 30 cm height and 98% of sprouts had basal diameter ranging from 0 to 20 mm only 105 days after planting. Indeed, the horizontal planting methods provided highest survival rate of sprouts than the vertical planting method (74%) of planted cuttings. Furthermore, the results show that, 105 days after planting, cuttings with horizontal method were more productive in terms of root development. In terms of planting method using water treatment, the horizontal planting method with water treatment showed highest rooting percentage (44%). Therefore, farmers should be trained and encouraged to use horizontal planting method using water treatment in order to get better results in regenerating bamboo through cuttings. 展开更多
关键词 BAMBOO bamboo regeneration culm cuttings cuttings planting methods.
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Effect of Maize/Haricot Bean Intercropping on Soil Fertility Improvement under Different Tied Ridges and Planting Methods, Southeast Ethiopia
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作者 Siraj Beshir Jemal Abdulkerim 《Journal of Geoscience and Environment Protection》 2017年第8期63-70,共8页
Mono cropping is the dominant factor influencing plant nutrient uptake and loss of soil quality in Ethiopia whereas intercropping of cereal/legume has positive environmental qualities. Likewise drought and moisture st... Mono cropping is the dominant factor influencing plant nutrient uptake and loss of soil quality in Ethiopia whereas intercropping of cereal/legume has positive environmental qualities. Likewise drought and moisture stress condition is widely expanding from all direction to the center of the country. Therefore, the objective of this research was to evaluate influence of planting methods, tied ridge and cropping system on different soil chemical properties in case of Madda Walabu district, Southeast Ethiopia. It was undertaken at Bidire from March 2016 to January, 2017. In this experiment, one maize variety (Melkassa 2) and one haricot bean variety (Nasir) were used. Treatments include open end and closed end tied ridge;sole cropping and intercropping;and in furrow, on ridge and flat bed planting. Each treatment has been triplicate and the experiment plots were laid out in randomized complete block design. Intercropping of maize-haricot bean with tied ridge and planting methods were highly influenced soil pH, exchangeable potassium, available phosphorous, soil organic matter and total soil nitrogen. Generally, the use of intercropping and closed end tied ridge in combination with in furrow planting significantly increased (p0.05) soil fertility in the system, which could be promising for sustainable improvement of crop production and productivity for semi arid areas of Bale zone. 展开更多
关键词 Tied Ridge INTERCROPPING plantING methods
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Entropy Method Based Evaluation for Plant Landscape in Tourist Scenic Spots 被引量:2
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作者 Xunfan SU Wenfeng YANG 《Asian Agricultural Research》 2017年第9期36-39,46,共5页
Taking five scenic spots in southeast region of Tibet as research objects,this paper calculated the weight of plant landscape evaluation system by entropy weight method,and compared the plant landscape in scenic spots... Taking five scenic spots in southeast region of Tibet as research objects,this paper calculated the weight of plant landscape evaluation system by entropy weight method,and compared the plant landscape in scenic spots from aesthetic effect,ecological harmony and service functions. The results show that the rank of the comprehensive attributes from high to low is as follows: Nanyigou,Lulang Forest,Kading Mountain Waterfall,Yarlung Zangbo Grand Canyon,and Basomtso Lake. 展开更多
关键词 Entropy method TIBET Scenic spots plant landscape evaluation
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New Methods in Genomic Research of Plants
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作者 STEWART J M KANTARTZI S K AVILA C A 《棉花学报》 CSCD 北大核心 2008年第S1期12-,共1页
Association mapping(as opposed to population mapping) is becoming more important in establishing associations between a phenotype and a genotype.The major advantage of association mapping,
关键词 New methods in Genomic Research of plants
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A Review of the Methods of Identifying and Testing Plant Cold Resistance
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作者 Xu Chengxiang 《Plant Diseases and Pests》 CAS 2015年第4期38-43,共6页
Low-tempemture stress is a major abiotic stress influencing plant growth, economic yield and quality worldwide. Precise and reliable identification and test of plant cold resistance is a foundation for exploring low-t... Low-tempemture stress is a major abiotic stress influencing plant growth, economic yield and quality worldwide. Precise and reliable identification and test of plant cold resistance is a foundation for exploring low-temperature damages, cold resistance mechanism of plants, cultivating and innovating quality cold-re- sistant germplasm resources, which is rather important for woody plants because their perennial and large-sized characteristics. Generally, most researches on plant cold-resistant physiology focused on identification and utilization of cold resistance worldwide, and a few on test methods of cold resistance, but cold resistance mechanism has been less reported. Therefore, researches on methods of identifying and testing plant resistance have achieved considerable progress, accumulated much experience and formed characteristics gradually in terms of methodology. Current methods of identifying plant cold resistance include open field/outdoor culti- vation evaluation, cold and frost damage investigation, simulated cold weather, and mathematical model forecast. And the methods of testing plant cold resistance include growth condition test, frozen index investigation, electrolyte leakage, bioelectrical impedance mapping and so on. Synthesizing the methods of identifying and testing plant cold resistance should be a key matter in the present and future researches and application of plant cold resistance physiology, improvement and in- novation of the identification and test will be an important direction of the future researches. Identification and test of plant cold resistance based on genomies, meta- bonomics and proteomics should be the new trend of the researches on physiology and ecology of plant cold resistance. 展开更多
关键词 plant Cold resistance Identification and test methods and technology PROSPECT
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基于Plant Simulation的钣金生产线仿真与优化 被引量:1
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作者 彭杰 叶霞 +1 位作者 潘艳飞 李仲树 《锻压技术》 北大核心 2025年第6期277-284,共8页
针对江苏长江智能制造研究院有限责任公司钣金生产线设备平均利用率较低和产能不足的问题,提出了基于Plant Simulation的生产线优化方案。首先,根据工艺路线建立了生产线数字化模型,运行仿真实验得到了生产线运行数据;其次,运用解释结... 针对江苏长江智能制造研究院有限责任公司钣金生产线设备平均利用率较低和产能不足的问题,提出了基于Plant Simulation的生产线优化方案。首先,根据工艺路线建立了生产线数字化模型,运行仿真实验得到了生产线运行数据;其次,运用解释结构模型法,确定了影响生产线高效运行的深层因素为缓存区的设置问题;最后,利用遗传算法,通过仿真实验得到了缓存区数量与容量的配置,再次优化生产线并进行了验证。结果表明,经过优化的钣金生产线的设备平均利用率提高了24%,每小时产量从55件提升至127件,提高了130%,为同类型生产线的优化提供了参考。 展开更多
关键词 生产线 plant Simulation 解释结构模型法 遗传算法 缓存区
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A Widely Applicable Method for Plant Genomic DNA Extraction
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作者 Bin LI Lixia YU +3 位作者 Junjun XI Yaping ZHANG Zerui GAO Bo YAN 《Agricultural Biotechnology》 CAS 2012年第1期29-30,共2页
[Objective] This study aimed to explore a method for plant genomic DNA extraction, to provide guidance for rapid extraction of genomic DNA from plant tissues. [ Method] Based on the published genomic DNA extraction me... [Objective] This study aimed to explore a method for plant genomic DNA extraction, to provide guidance for rapid extraction of genomic DNA from plant tissues. [ Method] Based on the published genomic DNA extraction methods, operation steps, reagent amount and processing time of SDS extraction method were optimized. [Result] A widely applicable method was established initially for genomic DNA extraction from various varieties of plants and various kinds of plant tissues. Quality of the extracted genomic DNA was relatively good, which meets the requirements for further operation. [ Conclusion] This study provided guidance for rapid plant genomic DNA extraction. 展开更多
关键词 plant genome DNA extraetion Optimized SDS extraction method
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番茄潜叶蛾卵在番茄植株冠层的空间分布格局
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作者 魏玉红 周昭旭 +1 位作者 刘月英 罗进仓 《生物安全学报(中英文)》 北大核心 2026年第1期48-55,共8页
【目的】明确番茄潜叶蛾卵在番茄植株冠层的空间格局及抽样技术,为其早期监测和防控提供依据。【方法】将处于营养生长阶段的盆栽番茄(9个复叶)放入养虫纱笼中,每笼1株,笼中释放3日龄成虫5~15对,3 d后调查记录植株冠层不同部位的卵量。... 【目的】明确番茄潜叶蛾卵在番茄植株冠层的空间格局及抽样技术,为其早期监测和防控提供依据。【方法】将处于营养生长阶段的盆栽番茄(9个复叶)放入养虫纱笼中,每笼1株,笼中释放3日龄成虫5~15对,3 d后调查记录植株冠层不同部位的卵量。根据卵量占比、聚集度指标、Iwao回归法及Taylor幂法则分析卵在植株冠层的空间分布特征,并使用相对方差RV和确定系数R^(2)确定最适抽样方式。【结果】在植株冠层,番茄潜叶蛾卵以叶片上卵量最多,占全株卵量的78.0%(其中叶正面54.3%、叶背面23.7%),显著高于叶柄(9.1%)、茎秆(6.8%)和顶芽(6.1%)的卵量,叶正面卵量显著高于叶背面,叶柄、茎秆和顶芽之间的卵量差异不显著。在植株冠层垂直分布中,以植株中部的卵量(49.7%)最多,显著高于上部(29.8%)和下部(20.5%)的卵量;叶片上的卵量以中部数量最多(48.4%),显著高于下部卵量(19.2%),而与上部卵量(32.4%)差异不显著,上部与下部卵量差异不显著;叶柄、茎秆和顶芽3个部位的卵量差异不显著。在冠层叶片水平分布上,外层卵量(46.2%)显著高于中层(31.0%)和内层(22.8%)。聚集度指标、Iwao回归法(m^(*)=-0.1255+3.5583m,r=0.9036,p<0.01)及Taylor幂法则(lgS^(2)=0.4887+1.3442lgm,r=0.9503,p<0.01)测定结果均表明,卵在植株冠层呈聚集分布,个体间相互排斥,聚集分布的原因与密度(m)呈正相关(λ=-0.1876+4.4395m,r=0.9468,p<0.01)。在几种抽样方式中,在植株冠层上、中、下部位分别各随机抽取2~5个叶片的取样方式,其相对方差RV为28.9%~29.7%,与总体样本的相对方差RV(30.9%)接近,其确定系数R^(2)为0.864~0.924,可用于田间抽样计划。【结论】在番茄植株冠层,番茄潜叶蛾卵呈聚集分布,叶片上的卵量显著多于叶柄、茎秆和顶芽卵量,植株中部的卵量高于植株上部和下部,植株冠层外层的卵量高于中层和内层。抽样方式以上、中、下部位分别各随机抽取2个以上叶片的取样方式为佳。 展开更多
关键词 番茄潜叶蛾 空间格局 抽样方式 番茄 植株冠层
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Development and Transition of Rice Planting in China 被引量:14
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作者 张玉屏 朱德峰 +3 位作者 熊洪 陈惠哲 向镜 林贤青 《Agricultural Science & Technology》 CAS 2012年第6期1270-1276,共7页
[Objective] This paper aimed to clarify the rice planting methods and its supporting technology to be developed in rice producing areas in China. [Method] Evolvement of rice planting methods in rice producing areas in... [Objective] This paper aimed to clarify the rice planting methods and its supporting technology to be developed in rice producing areas in China. [Method] Evolvement of rice planting methods in rice producing areas in China and in representative rice-growth countries abroad, its characteristics, adaptability and key issues were analyzed. [Result] The analysis of development of rice planting method in China and abroad indicated that rice planting method was adapted to rice-based cropping system and ecological environment, and its transition accompanied with social and economic development. With agricultural labor transfer from agriculture to other industries since 1990’s, rice seedling throwing was gradually applied and in recent decades, while direct seeding and machine transplanting were practiced. Now, hand transplanting is still the main rice planting method, adopted in 50% of national rice planting area; seedling throwing, direct seeding and machine transplanting are conducted in 25% , 12% and 13% of the national rice planting area. [Conclusion] Machine transplanting should be a leading rice planting method. Though area covered with machine direct seeding is still small up to now, it can be practiced in some rice growing area due to labor saving and low cost. Leading planting methods and its supporting key technologies are proposed in various rice producing areas in the future. 展开更多
关键词 RICE planting method Machine transplanting Seedling throwing Direct seeding RATOON
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植物蛋白基乳液凝胶脂肪替代物研究进展
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作者 朱秀清 王子涵 +4 位作者 黄雨洋 郭汝杞 刘琳琳 王颖 朱颖 《食品科学》 北大核心 2026年第4期305-314,共10页
随着消费者健康饮食意识的增强,脂肪替代物的开发日益受到关注。植物蛋白因其良好的功能特性,常被用作乳化剂或凝胶剂,在脂肪替代方面展现出巨大潜力,已成为研究热点。植物蛋白基乳液凝胶不仅具有营养价值,且在形态与口感上也与动物脂... 随着消费者健康饮食意识的增强,脂肪替代物的开发日益受到关注。植物蛋白因其良好的功能特性,常被用作乳化剂或凝胶剂,在脂肪替代方面展现出巨大潜力,已成为研究热点。植物蛋白基乳液凝胶不仅具有营养价值,且在形态与口感上也与动物脂肪相似;但在实际应用中,仍存在质地偏软、稳定性不足等问题。本文系统综述了植物蛋白基乳液凝胶的制备方法,重点探讨了不同添加物及制备方法对植物蛋白基乳液凝胶脂肪替代物结构和特性的影响及其机制,并总结和展望了其作为脂肪替代物在食品中的应用及未来研究方向,以期为植物基脂肪替代物的研究开发与应用提供理论依据。 展开更多
关键词 植物蛋白 乳液凝胶 脂肪替代物 制备方法 结构 特性
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电子芯片厂房装配式华夫板方案设计及有限元分析
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作者 温凌燕 聂鑫 +3 位作者 卢世杰 刘博文 孟姣 袁思遥 《工业建筑》 2026年第1期32-40,共9页
依托上海某电子芯片厂房项目,提出了一种整体装配式华夫板结构。通过有限元建模,计算叠合板拼缝深度和活载质量对楼板自振频率、刚度、原位频响函数的影响。随着叠合板拼缝深度的增加,华夫板同阶自振频率、刚度降低,楼盖振动响应增大,... 依托上海某电子芯片厂房项目,提出了一种整体装配式华夫板结构。通过有限元建模,计算叠合板拼缝深度和活载质量对楼板自振频率、刚度、原位频响函数的影响。随着叠合板拼缝深度的增加,华夫板同阶自振频率、刚度降低,楼盖振动响应增大,且叠合板拼缝深度越大,各个指标变化越快。当叠合板深度在100 mm以内时,华夫板动刚度、频响函数曲线峰值的变化在5%以内,证明了装配式混凝土华夫板方案的适用性。活载质量有利于楼盖对速度、加速度的控制,但不影响动刚度。采用单自由度体系推导的公式能够较准确地估算考虑活载后楼盖结构的位移、速度、加速度频响函数,可在工程中使用。 展开更多
关键词 芯片厂房 华夫楼盖 装配式 有限元法 频响函数 动刚度
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3种方法测定荒漠地区巨菌草蒸腾速率及其主要气象影响因子
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作者 严慧慧 李声繁 +7 位作者 刘凤山 王子怡 吕师 罗宗志 赖佳莉 岳锐 张智杰 林冬梅 《福建农林大学学报(自然科学版)》 北大核心 2026年第1期118-129,共12页
【目的】揭示巨菌草在西北荒漠干旱区的蒸腾耗水规律,明确影响其蒸腾作用的主要气象因子。【方法】采用快速称重法、整株容器法及波文比-能量平衡法测量日尺度下巨菌草的蒸腾速率,同时根据收集的相关气象因子数据,分析巨菌草蒸腾特征及... 【目的】揭示巨菌草在西北荒漠干旱区的蒸腾耗水规律,明确影响其蒸腾作用的主要气象因子。【方法】采用快速称重法、整株容器法及波文比-能量平衡法测量日尺度下巨菌草的蒸腾速率,同时根据收集的相关气象因子数据,分析巨菌草蒸腾特征及影响蒸腾速率的关键因子。【结果】巨菌草的蒸腾速率日变化呈现“单峰”曲线,于13:00—15:00达到峰值;在日尺度下,太阳辐射、相对湿度、饱和水汽压差、气温对巨菌草蒸腾速率的影响极显著(P<0.01),风速、土壤温度、土壤湿度对巨菌草蒸腾速率的影响较小;逐步回归分析结果显示,气象因子可解释75%以上蒸腾速率,说明回归分析模型准确性较高;巨菌草的日蒸腾耗水量达2.08~4.13 mm。【结论】采用快速称重法并在5 min内完成巨菌草蒸腾速率测定,测定值较接近真实值;整株容器法是测定巨菌草蒸腾速率更为合适的方法;植物蒸腾在蒸散发中占主导作用,贡献比例达85%。 展开更多
关键词 巨菌草 蒸腾速率 气象因子 整株容器法 快速称重法
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