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A phylogenetic approach identifies patterns of beta diversity and floristic subregions of the Qinghai-Tibet Plateau
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作者 Haibin Yu Man Yang +7 位作者 Zixin Lu Weitao Wang Fangyuan Yu Yonghua Zhang Xue Yin Hongjun Yu Junjie Hu David C.Deane 《Plant Diversity》 SCIE CAS CSCD 2024年第1期59-69,共11页
Patterns of taxonomic and phylogenetic beta diversity and their relationships with environmental correlates can help reveal the origin and evolutionary history of regional biota.The Qinghai-Tibet Plateau(QTP)harbors a... Patterns of taxonomic and phylogenetic beta diversity and their relationships with environmental correlates can help reveal the origin and evolutionary history of regional biota.The Qinghai-Tibet Plateau(QTP)harbors an exceptionally diverse flora,however,a phylogenetic perspective has rarely been used to investigate its beta diversity and floristic regions.In this study,we used a phylogenetic approach to identify patterns of beta diversity and quantitatively delimit floristic regions on the Qinghai-Tibet Plateau.We also examined the relationships between multifaceted beta diversity,geographical distance,and climatic difference,and evaluated the relative importance of various factors(i.e.,climate,topography and history)in shaping patterns of beta diversity.Sørensen dissimilarity indices indicated that patterns of species turnover among sites dominated the QTP.We also found that patterns of both taxonomic and phylogenetic beta diversity were significantly related to geographical distance and climatic difference.The environmental factors that contributed most to these patterns of beta diversity include annual precipitation,mean annual temperature,climatic gradients and climatic instability.Hierarchical dendrograms of dissimilarity and non-metric multidimensional scaling ordination based on phylogenetic beta diversity data identified ten floristic subregions in the QTP.Our results suggest that the contemporary environment and historical climate changes have filtered species composition among sites and eventually determined beta diversity patterns of plants in the QTP. 展开更多
关键词 Biogeographical regionalization Phylogenetic beta diversity Seed plants Sørensen dissimilarity Qinghai-Tibet Plateau
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Innovative use of intact seeds of Mucuna monosperma Wight for improved yield of L-DOPA
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作者 Shrirang INAMDAR Swati JOSHI +1 位作者 Jyoti JADHAV Vishwas BAPAT 《Natural Products and Bioprospecting》 CAS 2012年第1期16-20,共5页
The drug L-DOPA has been widely used against Parkinson's disease and is extracted from plants.Due to the increasing demand of this drug,new plant sources need to be discovered in addition to the existing sources.T... The drug L-DOPA has been widely used against Parkinson's disease and is extracted from plants.Due to the increasing demand of this drug,new plant sources need to be discovered in addition to the existing sources.The paper embodies results on Mucuna monosperma,which can be a promising candidate for L-DOPA.The seed powder of this plant contains 5.48%of(dry weight)the drug and when the seeds were soaked in distilled water,content was increased to 6.58%.Different elicitors when added,enhanced the drug level in seed up to 11.8%.The possible rationale behind this increase was confirmed by increase in tyrosinase activity in the seeds.Presence of L-DOPA was confirmed using various analytical techniques as HPLC,HPTLC and NMR.The work demonstrates a potential candidate plant as a source for L-DOPA when a novel method was adopted as described here. 展开更多
关键词 3-(3 4-dihydroxyphenyl)-L-alanine ELICITORS intact seeds Mucuna monosperma Parkinson’s disease TYROSINASE
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移动云系的平行条播方案与“S”型飞行航线设计研究
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作者 王晓青 张健南 +2 位作者 王姝怡 闫非 吴志会 《环境科学与管理》 CAS 2024年第5期36-39,127,共5页
在人工影响天气作业过程中,飞机作业航线设计是整个飞机增雨过程中最重要的技术工作,科学的飞机作业航线设计是提高云系催化效率以及检验催化作业效果的关键。针对平行条播方案,在充分考虑云系移速移向、飞机性能等基础上,提出优化的“... 在人工影响天气作业过程中,飞机作业航线设计是整个飞机增雨过程中最重要的技术工作,科学的飞机作业航线设计是提高云系催化效率以及检验催化作业效果的关键。针对平行条播方案,在充分考虑云系移速移向、飞机性能等基础上,提出优化的“S”型飞行航线设计方法,给出飞机转弯部分的简化处理方法,可快速确定关键点的位置,同时给出在标准转弯速率下空中国王350和运12飞机的转弯时间计算方法,对飞机增雨作业方案设计有很好的指导意义。实际飞行试验表明,增雨飞机可以按照设计的航线进行增雨作业,并且可实现平行条播。 展开更多
关键词 平行条播 “S”型航线 航线设计 飞机增雨
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合成钙矾石-水化硅酸钙复合晶种的水泥早强效应
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作者 李佳全 佟钰 +3 位作者 冷雨虹 王刚 赵明宇 房延凤 《中国粉体技术》 CAS CSCD 2024年第4期62-68,共7页
【目的】解析钙矾石-水化硅酸钙晶种的协同效应,改善普通硅酸盐水泥的早期力学强度。【方法】以溶液法合成的超细钙矾石和纳米水化硅酸钙为复合晶种,在微观结构表征基础上,探究钙矾石和水化硅酸钙的掺量以及水灰比对水泥净浆试块1、3 d... 【目的】解析钙矾石-水化硅酸钙晶种的协同效应,改善普通硅酸盐水泥的早期力学强度。【方法】以溶液法合成的超细钙矾石和纳米水化硅酸钙为复合晶种,在微观结构表征基础上,探究钙矾石和水化硅酸钙的掺量以及水灰比对水泥净浆试块1、3 d抗压强度的影响与作用机制。【结果】溶液法合成的超细钙矾石和纳米水化硅酸钙的纯度高,结晶完整,在水中可长时间保持稳定悬浮状态,适合作为复合晶种使用。当纳米水化硅酸钙质量分数固定为5%情况下,随着超细钙矾石掺量的增大,水泥净浆试块的早期抗压强度先升高后降低,在钙矾石掺量(质量分数,下同)为0.6%时,试块的1 d抗压强度提高125%;当钙矾石掺量为0.4%时,水泥净浆试块的3 d抗压强度提高57%。在超细钙矾石掺量一定情况下,水泥净浆试块早期强度随水化硅酸钙掺量的提高而明显增长,但掺量高于5%会导致泌水现象的发生。【结论】超细钙矾石与纳米水化硅酸钙作为复合晶种具有明显的协同效应,可有效提高普通硅酸盐水泥的早期力学强度,早强效果明显优于单独使用的钙矾石或水化硅酸钙晶种。 展开更多
关键词 钙矾石 水化硅酸钙 晶种 水泥 早强
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纳米C⁃S⁃H晶种与掺和料及早强剂复配对混凝土强度的影响
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作者 郁培云 张驰 +3 位作者 李书明 刘竞 郑新国 邓青山 《铁道建筑》 北大核心 2024年第4期107-111,共5页
为了提高混凝土早期强度,根据不同混凝土配方的组成差异,将纳米C‐S‐H晶种与掺和料以及早强剂复配,成型不同龄期的混凝土试件,分析复配后混凝土初终凝时间、抗压强度和抗折强度受到的影响。结果表明:粉煤灰和硅灰会降低混凝土的早期抗... 为了提高混凝土早期强度,根据不同混凝土配方的组成差异,将纳米C‐S‐H晶种与掺和料以及早强剂复配,成型不同龄期的混凝土试件,分析复配后混凝土初终凝时间、抗压强度和抗折强度受到的影响。结果表明:粉煤灰和硅灰会降低混凝土的早期抗压和抗折强度,纳米C‐S‐H晶种与粉煤灰、硅灰复配后可减弱粉煤灰、硅灰对强度下降的影响;纳米C‐S‐H晶种可缓解石膏的缓凝作用,并且可以与石膏、硫酸钠、硫铝酸盐水泥发挥协同作用,进一步提高混凝土的早期强度。 展开更多
关键词 纳米C‐S‐H晶种 混凝土 强度 掺和料 早强剂
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纳米C-S-H晶核对水泥浆体流变性能的影响
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作者 张心源 倪陈新 +3 位作者 陈稳 苏昂 姜骞 于诚 《新型建筑材料》 2024年第2期39-43,共5页
纳米C-S-H晶核由于对水泥早期水化的显著加速效果逐渐被广泛用作早强剂,通过流变仪测试掺纳米C-S-H晶核水泥浆体的塑性黏度、动态屈服应力、静态屈服应力和触变性,以研究纳米C-S-H晶核对水泥浆体流变性能的影响。结果表明:纳米C-S-H晶... 纳米C-S-H晶核由于对水泥早期水化的显著加速效果逐渐被广泛用作早强剂,通过流变仪测试掺纳米C-S-H晶核水泥浆体的塑性黏度、动态屈服应力、静态屈服应力和触变性,以研究纳米C-S-H晶核对水泥浆体流变性能的影响。结果表明:纳米C-S-H晶核掺入水泥浆体后,水泥浆体塑性黏度、动态屈服应力、静态屈服应力和触变性均随之增加,掺量越大,增加越多。水灰比对水泥浆体的流变性能也具有显著影响,水灰比越小,浆体的塑性黏度、动态屈服应力、静态屈服应力和触变性越大。 展开更多
关键词 纳米C-S-H晶核 流变性能 屈服应力 触变性
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3种元宝枫籽调味油对阿尔兹海默症小鼠的作用效果
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作者 何旭丽 秦礼康 +4 位作者 龙亭宇 孟若楠 刘庆灵 梁世康 谷荣辉 《中国粮油学报》 CAS CSCD 北大核心 2024年第5期138-147,共10页
为进一步开发与应用新资源食品元宝枫籽油,本研究探讨了3种元宝枫籽调味油对阿尔兹海默症(AD)小鼠的作用效果。采用Aβ25-35建立AD模型小鼠,并随机分为元宝枫籽油(Y)、元宝枫大蒜调味油(YD)、元宝枫麻辣调味油(YM)、元宝枫生姜调味油(YS... 为进一步开发与应用新资源食品元宝枫籽油,本研究探讨了3种元宝枫籽调味油对阿尔兹海默症(AD)小鼠的作用效果。采用Aβ25-35建立AD模型小鼠,并随机分为元宝枫籽油(Y)、元宝枫大蒜调味油(YD)、元宝枫麻辣调味油(YM)、元宝枫生姜调味油(YS)实验组,对各组进行连续21 d相应油脂[0.0025 mL/(g·d)]的灌胃干预;Y组设为阳性对照组(因元宝枫籽油已被多项研究证明具有改善AD的效果),以侧脑室注射生理盐水、连续21 d灌胃元宝枫籽油[0.0025 mL/(g·d)]干预的小鼠为假手术对照组(S)。同时,采用Morris水迷宫进行各组小鼠的行为学实验,测定其脑组织中超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、海马组织中过氧化物还原酶6(PRDX6)和谷胱甘肽过氧化酶1(GPX1)的mRNA相对表达量,观察海马区苏木精-伊红染色(HE)组织切片的形态特征并综合探讨各组油脂对AD的改善效果。与S组相比,Y组小鼠的学习记忆能力仅有略微下降;与Y组相比,YS组小鼠的学习记忆能力仅略有下降,YD、YM组小鼠的学习记忆能力显著下降(P<0.05);通过正向化和无量纲化处理,5组小鼠的抗氧化应激能力为S>Y>YS>YD>YM;在HE染色结果中,小鼠海马区的病变程度为S<Y<YS<YD<YM。元宝枫生姜调味油(YS)对抗AD有着积极的作用,可能是通过调控小鼠脑内的氧化应激通路实现的,具有重要的开发应用潜力。 展开更多
关键词 元宝枫籽油 元宝枫生姜调味油 阿尔兹海默症 AΒ25-35 学习记忆 氧化应激
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水化硅酸钙晶种研究进展
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作者 李茂 吴波 《四川建材》 2024年第4期1-3,共3页
水化硅酸钙(C-S-H)是人们使用最多的材料水泥的主要成分,其对水泥基材料的强度有很大贡献。人工合成CS-H晶种作为纳米材料掺入水泥基材料后,可以改变水泥基材料的水化产物进程,甚至可以为水泥基材料赋予特殊的性质。为此,介绍C-S-H晶种... 水化硅酸钙(C-S-H)是人们使用最多的材料水泥的主要成分,其对水泥基材料的强度有很大贡献。人工合成CS-H晶种作为纳米材料掺入水泥基材料后,可以改变水泥基材料的水化产物进程,甚至可以为水泥基材料赋予特殊的性质。为此,介绍C-S-H晶种的吸附作用和对水泥的外加剂作用,以及目前关于C-S-H晶种改性方面的研究。 展开更多
关键词 水化硅酸钙 晶种 水泥 吸附 改性
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Germination of Chenopodium Album in Response to Microwave Plasma Treatment 被引量:4
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作者 Bo■ena ER Vitězslav STRA■K +2 位作者 Michal ER■ Milan TICH■ Petr PATENKA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第4期506-511,共6页
The seeds of Lamb's Quarters (Chenopodium album agg.) were stimulated by low- pressure discharge. The tested seeds were exposed to plasma discharge for different time durations (from 6 minutes to 48 minutes). Ger... The seeds of Lamb's Quarters (Chenopodium album agg.) were stimulated by low- pressure discharge. The tested seeds were exposed to plasma discharge for different time durations (from 6 minutes to 48 minutes). Germination tests were performed under specified laboratory conditions during seven days in five identical and completely independent experiments. Significant differences between the control and plasma-treated seeds were observed. The treated seeds showed structural changes on the surface of the seat coat. They germinated faster and their sprout accretion on the first day of seed germination was longer. Germination rate for the untreated seeds was 15% while it increased approximately three times (max 55%) for seeds treated by plasma from 12 minutes to 48 minutes. 展开更多
关键词 early growth GERMINATION Lamb's Quarters seed enhancement stimulation surfatron discharge
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Hydration of Activated Anhydrate Phosphogypsum 被引量:2
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作者 杨敏 QIAN Jueshi +1 位作者 PAN Ling YANG Chengjun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第3期535-537,共3页
Phosphogypsum(PG) calcined at 500 ℃ was activated by K2SO4 and salt lime with loose structure as seed crystal. To determine the effect of activation, hydration of the anhydrate PG activated was investigated by exam... Phosphogypsum(PG) calcined at 500 ℃ was activated by K2SO4 and salt lime with loose structure as seed crystal. To determine the effect of activation, hydration of the anhydrate PG activated was investigated by examination of the setting time, the proportion of hydrated anhydrate PG, the microstructure of the hardenite and the resistance to water. Results show that activated anhydrate PG hydrates much more rapidly than that in the absence of activators. The activated anhydrate PG has proper setting time and hydrated proportion. The resistance to water was greatly improved. SEM photos show that the set activated PG has hydrated products of rod-like and closely connected crystals. The different addition of activator leads to different compact structure. 展开更多
关键词 HYDRATION anhydrate phosphogypsum ACTIVATION K2S04 seed crystal
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Allelopathy of Gaseous Volatiles of Eupatorium adenophorum on Seed Germination and Seedling Growth of Pinus yunanensis 被引量:1
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作者 Cao Zilin Wang Xiaoli +3 位作者 Li Genqian Li Xiaoting Gao Hui Yuan Sian 《Plant Diseases and Pests》 CAS 2013年第4期1-4,16,共5页
[ Objective] The paper was to understand allelopathy of gaseous volatiles of Eupatorium adenophorum stems and leaves on seed germination and seedling growth of P/nus yunnanens/s. [ Method] P. yunnanens/s seeds were tr... [ Objective] The paper was to understand allelopathy of gaseous volatiles of Eupatorium adenophorum stems and leaves on seed germination and seedling growth of P/nus yunnanens/s. [ Method] P. yunnanens/s seeds were treated by fresh stems and leaves of E. adenophorum in translucent airtight container under high concentration (0.069 4 g/cm3 ), middle concentration (0.023 1 g/cm3 ) and lower concentration (0. 007 7 g/cm3 ), respectively. [ Result] Gaseous volatiles affected seed germination process; with the increasing processing concentration, the day on which seeds began to germinate and the day reaching germination peak were delayed, and the germination quantity on the day reaching germination peak was decreased ; the day on which the germination quantity began to significantly re- duce was delayed ; the process curve was developed from sudden increase and sudden decrease to gentle change, and nearly became a beeline at high concentration. The effects of gaseous volatiles on seed germination ( seed germination rate, germination potential, germination index) and seedling growth (fresh weight, dry weight, radicle length, hypceotyl length) of P. yunnanens/s were basically consistent, showing a regularity that high concentration had stronger inhibition effect and the inhibition effect became weaker with the decreasing concentration of E. adenophorum. E. adenophorum was widely distributed under P. yunnanens/s forests, and might affect natural regeneration and growth of P. yunnanens/s via allelopathy. [ Conclusion ] The paper provides reference for scientific management of P. yunnanens/s forests. 展开更多
关键词 Eupator/um adenophorum Gaseous volatiles Pinus yunnanens/s Seed germination Seedling growth ALLELOPATHY
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Effects of Streptomyces <i>Biofertilizer</i>to Soil Fertility and Rhizosphere’s Functional Biodiversity of Agricultural Plants 被引量:3
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作者 Tinatin Doolotkeldieva Saykal Bobusheva Maxabat Konurbaeva 《Advances in Microbiology》 2015年第7期555-571,共17页
In the present study, a biofertilizer on the basis of Streptomyces fumanus gn-2 was used for the treatment of wheat and soybean seeds (dose 104 spore/ml) before planting them in soil with low fertility in order to det... In the present study, a biofertilizer on the basis of Streptomyces fumanus gn-2 was used for the treatment of wheat and soybean seeds (dose 104 spore/ml) before planting them in soil with low fertility in order to determine the effect of this biological agent on germination rate;the growth of seedlings, shoots, and the maturation phase of plants;the rhizosphere’s functional biodiversity;and the resistance of these plants to pathogens. Seeds were soaked in the suspension for a period of two or three hours. During the growing season of the crop, no additional fertilizing and spraying of a biopesticide against diseases or pests occurred. Despite the soil having low fertility, low quantities of organic matter, and not having been before used for the cultivation of agricultural plants, this biofertilizer showed a strong stimulatory effect on the growth of seeds and seedlings of wheat and soybeans. The average germination and seed vigor increased by 1.5 - 2.0 times, and the phenophases were accelerated to three to five days. In all phases of vegetation, the ammonifying bacteria in the presence of an antagonist (a biological agent) developed rapidly and were constantly present in significant numbers in the rhizosphere. Streptomyces fumanus introduced into non-sterile soil entered into competition with the local soil microflora and had the ability to colonize the rhizosphere system of plants. The use of a formulation of Streptomyces gn-2 has improved the composition of rhizosphere microflora, attracting saprophytic microorganisms: ammonificators and oligotrophs. The presence of the biocontrol microorganism Streptomyces fumanus in the rhizosphere plays an important role in enhancing the growth and development of useful groups, such as nitrogen-fixing bacteria. 展开更多
关键词 A Low Fertility Soil A BIofERTILIZER Streptomyces fumanus gn-2 Wheat and Soybean seeds Stimulatory Effect on Seed Germination Rhizosphere’s FUNCTIONAL BIODIVERSITY
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Low-Density Co-Inoculation of Myanmar <i>Bradyrhizobium yuanmingense</i>MAS34 and <i>Streptomyces griseoflavus</i>P4 to Enhance Symbiosis and Seed Yield in Soybean Varieties
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作者 Khin Myat Soe Takeo Yamakawa 《American Journal of Plant Sciences》 2013年第9期1879-1892,共14页
This study examined whether low-density co-inoculation of Myanmar Bradyrhizobium yuanmingense strain MAS34 and Streptomyces griseoflavus P4 would enhance nodulation, N2 fixation, and seed yield in two soybean varietie... This study examined whether low-density co-inoculation of Myanmar Bradyrhizobium yuanmingense strain MAS34 and Streptomyces griseoflavus P4 would enhance nodulation, N2 fixation, and seed yield in two soybean varieties. A field experiment was conducted during the July to November 2012 growing season at Kyushu University Farm, Japan, using a split-plot design with three replications and the following four treatments: T1, an uninoculated treatment with peat moss (uninoculated);T2, a single inoculation with S. griseoflavus P4 (P4);T3, a single inoculation of B. yuanmingense MAS34 (MAS34);and T4, a dual inoculation of P4 with MAS34 (P4 + MAS34). Two varieties of soybean, Yezin-3 (Rj4) and Yezin-6 (non-Rj), were used. The N2 fixation activity of soybean was evaluated by the relative ureide method using xylem solute from root bled sap at the early pod-fill stage (R3.5). Dry matter production, N2 fixation, and seed yield were significantly (P 0.01) different between the inoculated treatments. The effect of variety was also significant (P 0.05) for nodule dry weight at the V6 stage, percentage of N derived from the atmosphere at the R3.5 stage, and seed yield at the maturity stage. The number of nodules on the tap roots was significantly higher in Yezin-3 than in Yezin-6. The single inoculation of P4 did not have a significant effect on dry matter production, N2 fixation, and seed yield in either soybean variety. The dry matter production, relative ureide index, percentage of N derived from the atmosphere, and seed yield were significantly (P 0.01) enhanced by a single inoculation of MAS34 in Yezin-3 and by dual inoculation of P4 + MAS34 in Yezin-6. These results indicate that low inoculum concentrations (105 cells seed-1) increase N2 fixation and seed yield in these soybean varieties under open field conditions. Myanmar B. yuanmingense MAS34 and S. griseoflavus P4 are expected to be useful biofertilizers for soybean production. 展开更多
关键词 BRADYRHIZOBIUM yuanmingense N2 Fixation S. Griseoflavus P4 Seed Yield Soybean
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Feasibility of a New Granular Rapid Release Elemental S Fertilizer in Preventing S Deficiency of Canola on a S-Deficient Soil
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作者 Sukhdev S. Malhi Cecil L. Vera Stewart A. Brandt 《Agricultural Sciences》 2014年第11期1025-1036,共12页
Our previous research has indicated that granular elemental S (ES) fertilizers are not effective in the year of application and also are not consistently as effective as sulphate-S in increasing seed yield of canola i... Our previous research has indicated that granular elemental S (ES) fertilizers are not effective in the year of application and also are not consistently as effective as sulphate-S in increasing seed yield of canola in subsequent years, especially when applied at seeding in spring, because of slow dispersion of elemental S particles from granules for subsequent oxidation of ES to sulphate-S. A field experiment was established in autumn 2010 to determine the relative effectiveness of a new rapid release elemental S (RRES, now called Vitasul) fertilizer, in comparison to sulphate-S fertilizer, with various combinations of application times and placement methods (applied at 20 kg&middotS&middotha-1) on seed yield, straw yield, oil and protein concentration in seed, N and S uptake, partial factor productivity (PFP—kg&middotseed&middotkg-1 applied N&middotha-1—blanket application of 120 kg&middotN&middotha-1), S use efficiency (SUE—increase in kg&middotseed&middotkg-1 applied S&middotha-1) and percent recovery of applied S in seed + straw (%) of canola in 2011, 2012 and 2013 growing seasons on a S-deficient Gray Luvisol loam soil at Star City, Saskatchewan. The 11 treatments included two granular S sources (RRES and potassium sulphate) and five application time/placement method combinations (broadcast in autumn and incorporated in spring, broadcast in spring pre-tillage [broadcast and incorporated], broadcast in spring pre-emergence, sideband in spring and seedrow-placed in spring), plus a zero-S control. There was a significant response of seed yield of canola to applied S in all 3 years, but the responses varied with S source and with application time-placement combinations in different years. Seed yield increased considerably with all sulphate-S treatments compared to the zero-S control, although seed yield tended to be slightly lower in some spring and/or autumn broadcast treatments than the other sulphate-S treatments. Compared to the zero-S control, seed yield also increased significantly with all RRES treatments, but the increase was greater with autumn applied RRES than the spring applied RRES in many cases. Autumn applied RRES produced only slightly lower seed yield but spring applied RRES produced much lower seed yield than the highest yielding spring applied sulphate-S treatments. In 2011, straw yields increased significantly with applied S in some S treatments, but there was no significant effect of S fertilization on straw yield in 2012 and 2013. Oil concentration in canola seed increased only with sulphate-S fertilizer treatments in 2011, and it increased with both sulphate-S and ES sources in 2012 and 2013. There was no effect of any S treatment on the protein concentration in canola seed. The response trends of total N uptake and PFP were usually similar to seed yield for both S sources, but total S uptake, SUE and % recovery of applied S were lower with RRES than sulphate-S in many/most cases. In conclusion, the findings suggested the potential of spring broadcast pre-emergence RRES or autumn broadcast RRES in preventing S deficiency in hybrid canola, although seed yields were still slightly lower than the ideal highest yielding spring broadcast/incorporated sulphate-S treatment. 展开更多
关键词 CANOLA ELEMENTAL S N UPTAKE Oil Protein Seed Yield Sulphate-S S-Deficiency S UPTAKE
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Study on Virus-free Breeding Technology of Potato Microtuber
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作者 Chun LI Yuanjing XU 《Asian Agricultural Research》 2021年第11期56-58,共3页
It is the simplest,fastest and effective way to improve the yield level of potato by selecting high quality virus-free seed potato for field production and maintaining the original characters of virus-free minituber. ... It is the simplest,fastest and effective way to improve the yield level of potato by selecting high quality virus-free seed potato for field production and maintaining the original characters of virus-free minituber. Microtuber is featured by small volume,no pathogen,convenient storage and transportation,which can be induced in summer with high temperature and humidity,and overcome a series of problems such as poor survival rate of transplanted test-tube plantlets,and easy pollution of cutting tips. Therefore,it can replace conventional test-tube plantlets directly for reproduction. Meantime,if minitubers are sown ahead of time using cold frame,the growth stage of potato minituber will avoid the occurrence period of aphids. The use of gauze cover for insect prevention has good effect on maintaining the excellent characters of microtuber. The yield and quality of virus-free potato are greatly improved by means of virus-free culture of shoot tip seedlings,subculture propagation of virus-free seedlings,induction of microtubers by dark culture,cultivation of breeder’s seeds in greenhouse and screenhouse to preserve the characters of potato. 展开更多
关键词 POTATO VIRUS-FREE MICROTUBER Induction Breeder’s seed Seed character
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Protein Bodies in Cotyledon Cells Exhibit Differential Patterns of Legumin-Like Proteins Mobilization during Seedling Germinating States
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作者 Jose C. Jimenez-Lopez Maria C. Hernandez-Soriano 《American Journal of Plant Sciences》 2013年第12期2444-2454,共11页
Olive (Olea europaea L.) tree is one of the most extensive and important agricultural crop in Mediterranean countries due to its beneficial health and nutritional properties and its high economic value. Currently, oli... Olive (Olea europaea L.) tree is one of the most extensive and important agricultural crop in Mediterranean countries due to its beneficial health and nutritional properties and its high economic value. Currently, olive tree constitutes the sixth most important cultivated plant in the world, spreading from the Mediterranean region of origin to new production areas such as Australia, South and North America and South Africa. However, the mobilization processes of storage materials i.e. reserve proteins during seed germination, which are largely involved in essential physiological process including plant growth and development, remain poorly understood. Morphometric and immunohistochemistry analyses of protein bodies contained in olive seed storage tissues, cotyledon and endosperm, were performed by using different microscopy techniques, including light (bright-field and fluorescence) microscopy and transmission electron microscopy. Furthermore, we used legumin-like proteins (11S-type globulins) as a molecular marker to study the mobilization of reserve proteins from PBs of cotyledons at germinating seedling stages by using immunofluorescence assays. Results demonstrated that cotyledon and endosperm are characterized by distinct PBs populations containing legumin-like proteins, distinctly discriminated by the number of PBs per cell and tissue, size, immunofluorescence and histochemical staining. These features reflect differential PBs biogenesis during development and maturation processes in olive seed tissues endosperm and cotyledon, in relation to proteins (polypeptides) final composition, SSPs processing and/or packaging during seed maturation. Three different mobilization patterns of legumin-like proteins were identified for the first time in cotyledon PBs during seedling germinating process. Mature proteins composition and/or processing, cell types and enzyme composition and/or differential activation have been discussed as key features determining how proteins mobilize from PBs for further degradation in the cotyledon. 展开更多
关键词 11S GLOBULINS COTYLEDON Endosperm In Vitro Germination Legumin-Like PROTEINS Olea europaea L. Protein Bodies Seed PROTEINS MOBILIZATION
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Morphological Features of Plants and Yield of Sunflower Hybrids Cultivated in the Northern Part of the Forest-Steppe of Ukraine
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作者 S. Kalenska A. Ryzhenko +4 位作者 N. Novytska L. Garbar T. Stolyarchuk V. Kalenskyi O. Shytiy 《American Journal of Plant Sciences》 2020年第8期1331-1344,共14页
In Ukraine, a sunflower is the main oil crop from which more than 90% of vegetable fats are produced. An increase in production is due to the expansion of cultivation area, which necessitates research on sunflower hyb... In Ukraine, a sunflower is the main oil crop from which more than 90% of vegetable fats are produced. An increase in production is due to the expansion of cultivation area, which necessitates research on sunflower hybrids adaptability in the northern regions of Ukraine, where in recent decades</span></span><span><span><span>,</span></span></span><span><span><span><span> there has been a significant change of weather conditions and which may be favorable for its cultivation. The research was carried out in the Northern part of the Forest-Steppe of Ukraine on light loam chernozems. Reaction to growing conditions of four hybrids was studied by establishing the stability and plasticity of hybrids in terms of yield formation due to changes in morphological characteristics of plants. Yield potential realization is high enough, which is provided by sufficient amounts of positive, active, effective temperatures and precipitation. Calculation of the coefficients of plasticity and stability allows identifying stable sunflower hybrids, hybrids with a high level of </span><span>plasticity, and recommending them to production. The yield of ear</span><span>ly-maturing hybrid Ukrainskyi F1 increases rectilinearly with plant density increasing (r = 0.977 - 0.998), while hybrids P63LL06 (r = 0.651 - 0.882);NK Ferti (r = 0.589 - 0.846), and NK Brio (r = 0.689 - 0.804) form a higher yield at standing densities up to 60 thousand plants per hectare, and with further thickening, the yield decreases. With the thickening of sowings, the height of all hybrids plants increases (r = 0.97 - 0.99), and there is a decrease in the number of seeds per an</span></span></span></span><span><span><span>th</span></span></span><span><span><span>ode, and the weight of 1000 seeds. Sunflower hybrids can be divided into the groups according to the peculiarities of yield formation due to morphological features: 1) yield increases only due to sowings’ thickening</span></span></span><span><span><span>—</span></span></span><span><span><span> </span></span></span><span><span><span>Ukrainskyi F1;2) combined efficiency</span></span></span><span><span><span>-</span></span></span><span><span><span>increasing sowings’ density to 60 thousand plants/ha and generative organs formation</span></span></span><span><span><span><span>—</span><span>NCKBrio;3) hybrids of intermediate type</span><span>—</span><span>NK Ferti and P63LL06. 展开更多
关键词 SUNFLOWER YIELD Plasticity Stability Plant Height The Weight of 1000 seeds Individual Plant’s Productivity
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Photoperiod and Nitrogen Supply Limit the Scope of Northward Migration and Seed Transfer of Black Spruce in a Future Climate Associated with Doubled Atmospheric CO2 Concentration
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作者 Junlin Li Qing-Lai Dang Rongzhou Man 《American Journal of Plant Sciences》 2015年第1期189-200,共12页
The predicated changes in precipitation and temperature associated with the continued elevation of atmospheric CO2 concentration will trigger the northward shift of the Climate Envelopes for 130 North America tree spe... The predicated changes in precipitation and temperature associated with the continued elevation of atmospheric CO2 concentration will trigger the northward shift of the Climate Envelopes for 130 North America tree species by as much as 10 degrees. However, climate envelope models do not take into account changes in other factors that may also influence the survival and growth of plants at the predicted new locations, such as photoperiod and nutrient regimes. This study investigated how photoperiod and nitrogen supply would affect the ecophysiological traits of black spruce (Picea mariana (Mill) B. S. P.) that are critical for survival and growth at new locations predicted by climate envelope models. We exposed black spruce seedlings to the photoperiod regime at the seed origin (PS) and that 10° north of the seed origin (PNM) as predicted by climate envelope models under the current and doubled atmospheric CO2 concentration and different levels of N supply (30 vs. 300 μmol·mol-1 N). We found that the PNM and the 30 μmol·mol-1 N supply both had negative impact on the development of seedling cold hardiness in the fall, and led to earlier burst of the terminal bud and greater rate of mortality in the following growing season. While the PNM stimulated seedling growth in the first growing season, the effect was not sustained in the second growing season. Our results suggest that the photoperiod regimes and poor nutrient conditions at higher latitudes will likely constrain the scope of the northward migration or seed transfer of black spruce. 展开更多
关键词 Plant MIGRATION Tree Seed Transfer Nutrient Cold HARDINESS PICEA MARIANA (Mill) B.S.P. Boreal Forest Climate Envelope
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Several Strategic Issues in the Development of China's Seed Industry
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作者 Chen ZhixinYuan Longping Agncultural High-Tech Co., Ltd., Changsha 410001, China 《Agricultural Science & Technology》 CAS 2002年第1期12-15,共4页
Chinese agricultural industry and rural economy are currently undergoing a strategic restructuring. The Seed Act has been thoroughly enforced. The Development of West China program has also got started in an all-round... Chinese agricultural industry and rural economy are currently undergoing a strategic restructuring. The Seed Act has been thoroughly enforced. The Development of West China program has also got started in an all-round way. Not long ago China entered the World Trade Organization. All these not only present great opportunities but also severe challenges to China. 展开更多
关键词 Several Strategic Issues in the Development of China’s Seed Industry
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Biochemical Characteristics of Saint Mary’s Thistle Varieties (<i>Silybum marianum</i>L. <i>Gaertn.</i>) under Soil-Climate Conditions of the Khorezm Region
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作者 Umorbek K. Abdurakhimov Rustam M. Usmanov +3 位作者 Nurbek U. Khamraev Fatima R. Nurmetova Yulduzxon A. Matyakubova Anarjan A. Matkarimova 《American Journal of Plant Sciences》 2020年第7期987-993,共7页
This article deals with the biochemical characteristics of varieties of Saint Mary’s Thistle such as Panacea, Debut and Samaryanka. Based on the studies, it was found that the highest oil content was found in the spe... This article deals with the biochemical characteristics of varieties of Saint Mary’s Thistle such as Panacea, Debut and Samaryanka. Based on the studies, it was found that the highest oil content was found in the species Debut (26%). <span style="font-family:Verdana;">The lowest oil content was observed in the variety </span><span style="font-family:Verdana;">Samaryanka</span><span style="font-family:Verdana;"> (19%). The highest protein content and the sum of total amino acids in the seeds of St. Mary’s Thistle varieties were found in the variety Debut (131.1), and the lowest indication was observed in the species Samaryanka (79.2). By the number of replaceable amino acids existing in the seeds of the species of St. Mary’s Thistle, it was found in the Varieties Debut (126.3), and the lowest indication was observed in the variety Samaryanka (112). Based on the results of studies and the noted biochemical characteristics and varietal differences of the St. Mary’s Thistle, the possibility and expediency of expanding the crops of this species in the soil and climatic conditions of the Khorezm region are suggested. The research was conducted 2017-2019 y.</span> 展开更多
关键词 St. Mary’s Thistle Variety Biochemical Properties Chemical Composition Oil Content of seeds Oil Quality Essential and Replaceable Amino Acids Vitamins Soil and Climatic Conditions Khorezm Region
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