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Yield and Nutritive Values of Semi- and Non-Fall Dormant Alfalfa Cultivars under Late-Cutting Schedule in California’s Central Valley
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作者 Sultan Begna Dan Putnam +2 位作者 Dong Wang Khaled Bali Longxi Yu 《American Journal of Plant Sciences》 CAS 2024年第10期858-876,共19页
California is one of the major alfalfa (Medicago sativa L) forage-producing states in the U.S, but its production area has decreased significantly in the last couple of decades. Selection of cultivars with high yield ... California is one of the major alfalfa (Medicago sativa L) forage-producing states in the U.S, but its production area has decreased significantly in the last couple of decades. Selection of cultivars with high yield and nutritive value under late-cutting schedule strategy may help identify cultivars that growers can use to maximize yield while maintaining area for sustainable alfalfa production, but there is little information on this strategy. A field study was conducted to determine cumulative dry matter (DM) and nutritive values of 20 semi- and non-fall dormant (FD) ratings (FD 7 and FD 8 - 10, respectively) cultivars under 35-day cut in California’s Central Valley in 2020-2022. Seasonal cumulative DM yields ranged from 6.8 in 2020 to 37.0 Mg·ha−1 in 2021. Four FD 8 - 9 cultivars were the highest yielding with 3-yrs avg. DM greater than the lowest yielding lines by 46%. FD 7 cultivar “715RR” produced the highest crude protein (CP: 240 g·Kg−1) while FD 8 cultivar “HVX840RR” resulted in the highest neutral detergent fiber digestibility (NDFD: 484 g·Kg−1, 7% greater than the top yielding cultivars) but with DM yield intermediate. Yields and NDFD correlated positively but weakly indicating some semi- and non-FD cultivars performing similarly. These results suggest that selecting high yielding cultivars under 35-day cutting schedule strategy can be used as a tool to help growers to maximize yield while achieving good quality forages for sustainable alfalfa production in California’s Central Valley. 展开更多
关键词 ALFALFA Maximizing yield Nutritive value CULTIVAR Cutting Schedule Production Area California
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Sustainability Assessment of Banana (Musa spp.) Yield Gap Reduction through Value Chain Development Interventions in Smallholder Farming Systems in Manicaland, Zimbabwe
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作者 Mthintwa Tawanda Hove Hlamalani Ngwenya Johan Van Niekerk 《Agricultural Sciences》 2024年第8期962-992,共31页
This study evaluated the effectiveness of donor supported agricultural value chain development projects in sustainably narrowing yield gaps for banana smallholder farmer producers in Manicaland, Zimbabwe. The study us... This study evaluated the effectiveness of donor supported agricultural value chain development projects in sustainably narrowing yield gaps for banana smallholder farmer producers in Manicaland, Zimbabwe. The study used a mixed methods research design that relied on farmers records for the quantitative analysis and focus group discussion and in-depth interviews for key experts for the qualitative aspects. A mix of regression analysis, t-tests, Pearsons’s correlation and analysis of variance statistical methods were used for the quantitative analysis while thematic response analysis was used for the qualitative engagements. The findings showed that by the end of the activity, the project had successfully narrowed the banana yield gaps to 18.66 tons per hectare working with a potential yield base of 40 tons. However, 5 years after the project closure the yield gap had fallen to 24.7 tons indicating a lack of sustainability of yield gap reduction. However, the yield gap slump does not override the fact that farmers on average were still able to sell approximately 5 tons per every 6 months after 5 years from the project closure which is beyond any poverty threshold. This suggests genuine upward economic mobility. Additionally, in analyzing what factors had the greatest influence on yield gap reduction, the access to fertilizer ranked highest where genetics, irrigation and improved agronomy followed in that respective order. The study further showed that farmers who receive value chain development support whilst at an already commercialized state tend to maintain productivity thresholds higher in comparison to those who are at a pre commercial state. This is evidenced by the fact that the pre commercial farmers had a yield reduction of 30.83 percent after 5 years of the project closure whereas the former realized a productivity growth of 7.84%. In conclusion, whilst the intervention was successful in transitioning farmers out of poverty, more investment should be made towards transitioning smallholder farmers to integrated soil fertility management practices and improvement of agronomic efficiency through stronger on field collaboration between research institutions, the government and development institutions. 展开更多
关键词 yield Gap value Chain Development Soil Health Varietal Replacement Rate Sustainability and Economic Mobility
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Correlation Analysis of SPAD Value with Chlorophyll Content and Economic Yield Traits of Brassica napus L. 被引量:6
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作者 高建芹 浦惠明 +4 位作者 张洁夫 龙卫华 陈锋 周晓婴 张维 《Agricultural Science & Technology》 CAS 2013年第10期1421-1428,共8页
[Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish reg... [Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish regression functions. [Method] Based on 34 Brassica napus L. varieties, SPAD value, chlorophyll content, agronomic characters, economic characters and yield traits were measured and re- gression functions were established according to correlations. [Result] SPAD value, chlorophyll content, agronomic and economic characters and yield traits all achieved significant level in differences among 34 varieties. Specifically, SPAD value was of extremely significant correlation with chlorophyll a and b, total chlorophyll and carotenoid, and the correlation from high to low was chl-b〉chl-z〉chl-a〉chl-x. SPAD value was of significantly positive correlation with total pod number per plant, plant height, seed number per pod, yield per plant and harvest yield, and of insignificant correlation with branch point height, effective branch number, pod density of main stem, and pod length. [Conclusion] It is simple and rapid to predict chlorophyll con- tent, economic characters and yields of Brassica napus L. with SPAD value and re- gression functions. 展开更多
关键词 Brassica napus L. SPAD value Chlorophyll content Economic yield Correlation analysis
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Effects of Nitrogen Level and High Temperature Stress on Yield, SPAD Value and Soluble Sugar Content of Early Rice Ganxin 203 被引量:2
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作者 杨军 余秋英 +10 位作者 陈小荣 朱昌兰 彭小松 贺晓鹏 傅军如 欧阳林娟 边建民 胡丽芳 孙晓棠 徐杰 贺浩华 《Agricultural Science & Technology》 CAS 2016年第2期385-390,共6页
This study aimed to investigate the combined effects of nitrogen level (high and ordinary) and high temperature stress (37 ℃, 4 d) at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar con... This study aimed to investigate the combined effects of nitrogen level (high and ordinary) and high temperature stress (37 ℃, 4 d) at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar content of Ganxin 203, an early rice cultivar. The results showed that under both high and ordinary nitrogen levels, high temperature stress reduced the seed-setting rate, yield per stem, SPAD value and soluble sugar content of Ganxin 203; under both high and ordinary tem- peratures, high nitrogen level increased the seed-setting rate, yield per stem and soluble sugar content of Ganxin 203; the seed-setting rate, yield per stem and yield per plant of Ganxin 203 under high temperature and high nitrogen level were higher than those under high temperature and ordinary nitrogen level. It suggests that ap- propriate high nitrogen level contributes to weakening the negative effects of high temperature stress on rice yield. 展开更多
关键词 RICE Late panicle initiation stage High temperature yield SPAD value Nitrogen level
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Loss Rate Estimation of Yield and Output Value of Tobacco Leaf Infected by Tobacco Blown Spot (Alternaria alternata) 被引量:3
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作者 余清 《Plant Diseases and Pests》 CAS 2010年第6期23-27,63,共6页
[Objective] The paper was to study the effect of tobacco blown spot on the yield and output value of tobacco leaf.[Method]The upper,middle and lower leaves in tobacco plant were selected during the harvest period of t... [Objective] The paper was to study the effect of tobacco blown spot on the yield and output value of tobacco leaf.[Method]The upper,middle and lower leaves in tobacco plant were selected during the harvest period of tobacco to carry out loss rate estimation of yield and output value of tobacco leaf caused by different disease levels of brown spot.Regression correlation analysis was also conducted.[Result]The disease levels of brown spot had extremely significant strong negative correlation with single leaf weight of tobacco leaf,and it had extremely significant strong positive correlation with the loss rate of single leaf weight.The increase speed of loss rate of single leaf weight of middle and upper leaves was obviously faster than that of lower leaves.The loss rates of single leaf weight of upper,middle and lower leaves were 3.18%-28.95%,3.43%-28.88% and 10.07%-26.90%,respectively.The higher the disease level of blown spot was,the lower the yield and output value of tobacco leaf was,and the corresponding loss rate was also higher.Correlation analysis showed that the disease level of blown spot had extremely significant strong negative correlation with the yield and output value of tobacco leaf,and it had extremely significant strong positive correlation with the loss rate of yield and output value.The negative impact of blown spot on the output value of tobacco leaf was far greater than that on the yield.The highest loss rate of the yield of tobacco leaf was 28.56%,while the highest loss rate of output value reached 89.67%.[Conclusion] The study provided theoretical basis for accurately holding the critical period for the control of blown spot,thus reducing the damage on tobacco leaf and improving the output value of tobacco leaf. 展开更多
关键词 Tobacco brown spot Single-leaf weight yield of tobacco leaf Output value of tobacco leaf Loss rate estimation
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Effects of Different Biochar Dosages and Types on Growth, Yield and Output Value of Flue-cured Tobacco in Hanzhong Area
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作者 牛玉德 聂兆君 +8 位作者 李金峰 韩治建 杨宏星 王国良 梅运鹏 李先锋 汤建华 叶协锋 刘红恩 《Agricultural Science & Technology》 CAS 2015年第11期2476-2480,共5页
[Objective] This study was to investigate the effects of different biochar dosages and trpes on growth, yield and output value of flue-cured tobacco in Hanzhong. [Methods] In May-September of 2013, Xiaonanhai Town, Na... [Objective] This study was to investigate the effects of different biochar dosages and trpes on growth, yield and output value of flue-cured tobacco in Hanzhong. [Methods] In May-September of 2013, Xiaonanhai Town, Nanzheng County, Hanzhong City, a field experiment was carded out to study the effects of- biochardosage and type on tobacco agronomic traits, yield and output value in each growth period. [Results] Biochar application significantly increased plant height, stem diameter and leaf size in the early growth pedod, and raised tobacco yield, output value and the proportion of high grade leaf: With the increase of biochar dosage, tobacco agronom~ traits were significantly improved, and yield, output value and proportion of high-grade tobacco leaves also increased significantly, and the highest tobacco yield and output value occurred at the dosage of 900 kg/hm2. Agronomic traits of tobacco leaves with the application of rice husk char and wheat straw char were significantly better than those with the application of peanut shell char, appli- cation of rice husk char was more conducive to the development of leaves in the vigorous pedod and stems in the squaring period, but straw char was beneficial to improvement of plant height and leaf number in the vigorous period and leaf growth in the squaring period, and application of rice husk char had the best effect on the increases of yield and output value of tobacco leaves. [Conclusion] Application of biochar is an effective measure forimproving tobacco-planting soil and promoting the growth and development of tobacco in Hanzhong, biochar application amount should be controlled at about 600-900 kg/hm2, and rice husk char is the preferred choice as soil improvement material. 展开更多
关键词 Flue-cured tobacco BIOCHAR Agronomic traits yield and output value
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Energy Values of Registered Corn Forage Hybrids in France over the Last 20 Years Rose in a Context of Maintained Yield Increase
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作者 Aurélie Baldy Marie-Pierre Jacquemot +3 位作者 Yves Griveau Cyril Bauland Matthieu Reymond Valérie Mechin 《American Journal of Plant Sciences》 2017年第6期1449-1461,共13页
The cultivation of corn silage has developed in France since the 1970s to reach 1.5 million of hectares nowadays. Since 1998, a feeding value criterion (namely UFL for “Unité Fourrage Laitière”) has been t... The cultivation of corn silage has developed in France since the 1970s to reach 1.5 million of hectares nowadays. Since 1998, a feeding value criterion (namely UFL for “Unité Fourrage Laitière”) has been taken into account to register forage varieties in the French forage maize hybrids catalog in addition to other criteria related to plant agronomical performances such as yield, earliness and lodging resistance. It is frequently stated that the improvement of plant’s agronomic performances would led to a decline in forage energy value. Decline of “Unité Fourrage Laitière” values has been repeatedly reported and the expected increase was not yet visible in 2002. In the present study, a set 47 early and mid-early hybrids commercialized in France between 1958 and 2015 has been cultivated in 3 locations in France. “Unité Fourrage Laitière” values and yield have been estimated in order to shed light on the evolution of feeding value criteria during this period and to conclude on the evolution of “Unité Fourrage Laitière” values since the introduction of this criterion for registration. Results obtained in our study demonstrated a recent rise in “Unité Fourrage Laitière” value in a context of strong yield increase. This increase was not necessarily attributable to high cob proportion in the harvested silage. Breeder’s work since the 2000’s has succeeded to offer hybrids that recover “Unité Fourrage Laitière” values similar to the ones of hybrids from the 1960’s (Royal, 1960, 91 UFL/100 kg DM). We propose to accentuate this effort targeting the enhancement of lignocellulosic cell wall digestibility to breed for future forage maize hybrids. 展开更多
关键词 Maize FORAGE UFL value yield BREEDING
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Effect of Different Mulch Paper on Growth and Yield of Different High Value Vegetables in Bangladesh
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作者 Ferdouse Islam AKM Quamruzzaman Sharmila Rani Mallick 《Agricultural Sciences》 2021年第3期237-246,共10页
The study was undertaken to identify the suitable mulch paper for different high-value vegetables during the winter season of November 2019 to March 2020 at the Olericulture research field of Bangladesh Agricultural R... The study was undertaken to identify the suitable mulch paper for different high-value vegetables during the winter season of November 2019 to March 2020 at the Olericulture research field of Bangladesh Agricultural Research Institute, Gazipur, Bangladesh. The study was a randomized complete block design with 3 replications. Four vegetable varieties viz., tomato, brinjal, capsicum and broccoli and 3 mulch treatments viz., T1 = Silver over black mulch;T2 = Black mulch;T3 = No mulch were included in this study. Different vegetables responded differently with the changes of mulches irrespective of different characters. it was clear that fruit number, average fruit weight, fruit length, fruit diameter were strongly related to soil moisture content. The effect of different plastic mulches on fruit weight per plant and yield (t/ha) was significant. Mulching produced higher fruit yield per plant and fruit yield per hectare than for the control, indicating that the mulch had a positive effect in generating increased fruit yield. Silver over black plastic mulch produced the highest fruit yield viz., 98.05 t/ha (tomato), 54.11 t/ha (brinjal), 34.33 t/ha (capsicum), 26.09 t/ha (broccoli) followed by black and no mulches, while the control plot produced the lowest fruit yield. 展开更多
关键词 Mulch Paper Growth yield High value Vegetables BANGLADESH
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Short-Term Effect of Grazing Exclusion and Uncontrolled Grazing on Species Abundance, Dry Matter Yield and Nutritive Value in an Invaded Area by Euryops floribundus in the Eastern Cape, South Africa
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作者 Sive Tokozwayo Eric Cofie Timpong-Jones +6 位作者 Keletso Mopipi Masibonge Gxasheka Unathi Gulwa Siza Mthi Mthunzi Mndela Mzwethu Dastile Azile Dumani 《Open Journal of Ecology》 2023年第6期321-333,共13页
Grazing exclusion (GE) is the most effective rangeland restoration technique which facilitates species diversity and forage quality. This study aimed at assessing short-term impact of GE and continuously grazed rangel... Grazing exclusion (GE) is the most effective rangeland restoration technique which facilitates species diversity and forage quality. This study aimed at assessing short-term impact of GE and continuously grazed rangeland on relative frequency, dry matter yield and nutritive value of dominant grasses in an area invaded by Euryops floribundus. A plot of 2.5 ha was measured and the boundaries demarcated using tape measure and steal pins, the plot was further divided into two subplots of 1ha each which were 5 m apart. One subplot was fenced and protected from grazing livestock, while one subplot was grazed continuously and not fenced. Three parallel belt transects of 100 m × 2 m with 3 m apart were laid out in both subplots. Woody plants occurring within the transects were identified and recorded to determine density. In each subplot, a 0.25 m<sup>2</sup> quadrant measuring was thrown randomly to take detailed records on plant species, relative frequency of species and herbage biomass. Four dominant species at the two sites were harvested to determine the nutritive value. Results indicate that grazing exclusion (GE) facilitates grass species diversity, subsequently sixteen and thirteen grasses species were recorded in the GE and uncontrolled grazed (UG) sites, respectively. Eragrostis chloromelas (21.7%), and Themeda triandra (13.2%) had high relative frequencies in the GE site. Highest biomass production was recorded in the GE site (1400 kg·ha<sup>-1</sup>) compared to UG site (1102 kg·ha<sup>-1</sup>). Crude protein content was relatively lower at UG site (5.4% - 5.8%) as compared to GE site (7.2% - 7.8%). It was concluded that, GE showed a positive impact on a relative frequency (%), dry matter yield and crude protein content. UG creates a conducive environment for Euryops recruitment. Further studies are required to examine the impact of GE in long-term trial setup. 展开更多
关键词 Dry Matter yield Crude Protein Nutritive value Relative Frequency
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The Edible and Medicinal Value of <i>Coix lacryma-jobi</i>and Key Cultivation Techniques for High and Stable Yield
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作者 Li Feng Yonghong Zhao +4 位作者 Zhuqi Zhang Shengai Zhang Hongxia Zhang Mingli Yu Yiwei Ma 《Natural Resources》 2020年第12期569-575,共7页
<span style="font-family:;" "=""><span style="font-family:Verdana;">In this paper, it was introduced that </span><i><span style="font-family:Verdana;&... <span style="font-family:;" "=""><span style="font-family:Verdana;">In this paper, it was introduced that </span><i><span style="font-family:Verdana;">Coix lacryma-jobi</span></i><span style="font-family:Verdana;"> is a traditional dual-</span></span><span style="font-family:;" "=""><span style="font-family:Verdana;">use edible and medicine crops in China, and the nutritional components and medicinal value of </span><i><span style="font-family:Verdana;">Coix lacryma-jobi</span></i><span style="font-family:Verdana;"> were described. Based on the published literature at home and abroad, a variety of chemical components found in </span><i><span style="font-family:Verdana;">Coix lacryma jobi</span></i><span style="font-family:Verdana;"> and their medicinal effects were reviewed. At the same time,</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">the problems existing in the production of </span><i><span style="font-family:Verdana;">Coix lacryma jobi</span></i><span style="font-family:Verdana;"> were put forward. With the improvement of people’s living standards, the nutritional and health care value of </span><i><span style="font-family:Verdana;">Coix lacryma-jobi</span></i><span style="font-family:Verdana;"> has been paid more and more attention.</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">The problems of </span><i><span style="font-family:Verdana;">Coix lacryma-jobi</span></i><span style="font-family:Verdana;"> in production were analyzed.</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">Some biological characteristics of </span><i><span style="font-family:Verdana;">Coix lacryma-jobi</span></i><span style="font-family:Verdana;">, especially its hygrophyte characteristics, were re-recognized, which is very important to increase the yield of </span><i><span style="font-family:Verdana;">Coix lacryma jobi</span></i><span style="font-family:Verdana;">. In the paper, the key cultivation techniques for high and stable yield of </span><i><span style="font-family:Verdana;">Coix lacryma-jobi</span></i><span style="font-family:Verdana;"> were also summarized. In order to obtain high quality, high and stable yield, we should adopt the new technical methods of “two wet, two dry and two water” in water management. At </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">same time, if artificial pollination is applied in the peak of flowering period, the seed setting rate and the yield will be increased.</span> 展开更多
关键词 Artificial Pollination Edible and Medicinal value High and Stable yield Key Cultivation Techniques yellow River Delta
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QUANTITATIVE RELATION BETWEEN YIELD STRESS AND R-VALUE OF Ti PLATE ALONG PARALLEL AND PERPENDICULAR TO ROLLING DIRECTION
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作者 ZHANG Derong Shenyang Institute of Aeronautical Engineering,Shenyang,China ZHANG Derong Associate Professor.Dept.of Aeronautics,Shenyang Institute of Aeronautical Engineering,Shenyang 110031,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1990年第9期196-199,共4页
An attempt was made on the quantitative prediction of the relationship hetween the yield stress and R-value along the parallel and perpendicular to the rolling direction of Ti plate based on analysis of the previous e... An attempt was made on the quantitative prediction of the relationship hetween the yield stress and R-value along the parallel and perpendicular to the rolling direction of Ti plate based on analysis of the previous experimental data.It is shown that the yield stress along one direction and another is quite synchronized with the R—value.According to the plasticity theo- ry,an formular of σ_(1s)/σ_(2s)=[(1+1/R_2)/(1+1/R_1)/^(1 2) was proposed,In statistic estima- tion.the calculated results are in good agreement with the experimental data.The availability of this formula was briefly discussed also. 展开更多
关键词 titanium plate yield stress R-value
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QUANTITATIVE RELATIONSHIP BETWEEN YIELD STRESS AND r-VALUE OF Ti SHEET
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作者 ZHOU Weixian Northwestern Polytechnical University,Xi′an,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1992年第3期188-192,共5页
Based on the experimental data,it was clarified that the plastic strain ratio R-value is not equal to Hill's r-value for Ti sheet.From the non-quadratic orthotropic yield function pro- posed recently by the author... Based on the experimental data,it was clarified that the plastic strain ratio R-value is not equal to Hill's r-value for Ti sheet.From the non-quadratic orthotropic yield function pro- posed recently by the author,an optimal expression between yield stress and r-value for Ti sheet was developed on overall investigation.The suitable value of exponent in the function seems to be 6—8.Thus,an equation was suggested to estimate strength for the pressure vessel made of Ti sheet. 展开更多
关键词 Ti sheet yield stress R-value ANISOTROPy
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Soil phosphorus dynamic, balance and critical P values in longterm fertilization experiment in Taihu Lake region, China 被引量:16
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作者 SHI Lin-lin SHEN Ming-xing +4 位作者 LU Chang-yin WANG Hai-hou ZHOU Xin-wei JIN Mei-juan WU Tong-dong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2446-2455,共10页
Phosphorus(P) is an important macronutrient for plant but can also cause potential environmental risk. In this paper, we studied the long-term fertilizer experiment(started 1980) to assess the soil P dynamic, bala... Phosphorus(P) is an important macronutrient for plant but can also cause potential environmental risk. In this paper, we studied the long-term fertilizer experiment(started 1980) to assess the soil P dynamic, balance, critical P value and the crop yield response in Taihu Lake region, China. To avoid the effect of nitrogen(N) and potassium(K), only the following treatments were chosen for subsequent discussion, including: C0(control treatment without any fertilizer or organic manure), CNK treatment(mineral N and K only), CNPK(balanced fertilization with mineral N, P and K), MNK(integrated organic manure and mineral N and K), and MNPK(organic manure plus balanced fertilization). The results revealed that the response of wheat yield was more sensitive than rice, and no significant differences of crop yield had been detected among MNK, CNPK and MNPK until 2013. Dynamic and balance of soil total P(TP) and Olsen-P showed soil TP pool was enlarged significantly over consistent fertilization. However, the diminishing marginal utility of soil Olsen-P was also found, indicating that high-level P application in the present condition could not increase soil Olsen-P contents anymore. Linear-linear and Mitscherlich models were used to estimate the critical value of Olsen-P for crops. The average critical P value for rice and wheat was 3.40 and 4.08 mg kg^(–1), respectively. The smaller critical P value than in uplands indicated a stronger ability of P supply for crops in this paddy soil. We concluded that no more mineral P should be applied in rice-wheat system in Taihu Lake region if soil Olsen-P is higher than the critical P value. The agricultural technique and management referring to activate the plant-available P pool are also considerable, such as integrated use of low-P organic manure with mineral N and K. 展开更多
关键词 long-term fertilization soil P dynamic soil P balance crop yield critical P value
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pH Value Effects in Shear Rheology of Concentrated Alumina Suspensions 被引量:1
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作者 曾人杰 魏光 B.Rand 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第2期180-183,共4页
The influence of pH on the rheological properties of concentrated alumina suspensions was investigated. At various pH values, the alumina exhibited pseudoplastic, near Bingham flow behaviors. The fully-deflocculated s... The influence of pH on the rheological properties of concentrated alumina suspensions was investigated. At various pH values, the alumina exhibited pseudoplastic, near Bingham flow behaviors. The fully-deflocculated suspensions exhibited Newtonian flow behaviors, while the fully-flocculated suspensions demonstrated very high viscosity and shear yield stress. 展开更多
关键词 shear rate shear stress extrapolated shear yield stress plastic viscosity pH value
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Growth, yield and fiber quality characteristics of Bt and non-Bt cotton cultivars in response to boron nutrition 被引量:1
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作者 MEHRAN Muhammad ASHRAF Muhammad +4 位作者 SHAHZAD Sher Muhammad SHAKIR Muhammad Siddique AZHAR Muhammad Tehseen AHMAD Fiaz ALVI Alamgir 《Journal of Cotton Research》 CAS 2023年第1期1-12,共12页
Background Boron(B)deficiency is an important factor for poor seed cotton yield and fiber quality.However,it is often missing in the plant nutrition program,particularly in developing countries.The current study inves... Background Boron(B)deficiency is an important factor for poor seed cotton yield and fiber quality.However,it is often missing in the plant nutrition program,particularly in developing countries.The current study investigated B’s effect on growth,yield,and fiber quality of Bt(CIM-663)and non-Bt(Cyto-124)cotton cultivars.The experimental plan consisted of twelve treatments:Control(CK);B at 1 mg·kg^(−1) soil application(SB1);2 mg·kg^(−1) B(SB2);3 mg·kg^(−1) B(SB3);0.2%B foliar spray(FB1);0.4%B foliar spray(FB2);1 mg·kg^(−1) B+0.2%B foliar spray(SB1+FB1);1 mg·kg^(−1) B+0.4%B foliar spray(SB1+FB2);2 mg·kg^(−1) B+0.2%B foliar spray(SB2+FB1);2 mg·kg^(−1) B+0.4%B foliar spray(SB2+FB2);3 mg·kg^(−1) B+0.2%B foliar spray(SB3+FB1);3 mg·kg^(−1) B+0.4%B foliar spray(SB3+FB2).Each treat-ment has three replications,one pot having two plants per replication.Results B nutrition at all levels and methods of application significantly(P≤0.05)affected the growth,physiological,yield,and fiber quality characteristics of both cotton cultivars.However,SB2 either alone or in combination with foliar spray showed superiority over others,particularly in the non-Bt cultivar which responded better to B nutrition.Maxi-mum improvement in monopodial branches(345%),sympodial branches(143%),chlorophyll-a(177%),chlorophyll-b(194%),photosynthesis(169%),and ginning out turn(579%)in the non-Bt cultivar was found with SB2 compared with CK.In Bt cultivar,although no consistent trend was found but integrated use of SB3 with foliar spray performed relatively better for improving cotton growth compared with other treatments.Fiber quality characteristics in both cultivars were improved markedly but variably with different B treatments.Conclusion B nutrition with SB2 either alone or in combination with foliar spray was found optimum for improving cotton’s growth and yield characteristics. 展开更多
关键词 BORON COTTON Fiber length Fiber strength GOT Micronaire value Seed cotton yield
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Investigation of Tree Structure Parameters of High-quality and High-yielding Y-shaped Pear Orchards 被引量:1
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作者 Shuwei WEI Shaomin WANG +2 位作者 Ran DONG Kun RAN Hongwei WANG 《Agricultural Biotechnology》 CAS 2019年第2期101-103,共3页
In order to study reasonable tree structure parameters of Y-shaped pear orchards in natural conditions and at management technical level of Tai'an area, the tree structure and population structure of high-quality ... In order to study reasonable tree structure parameters of Y-shaped pear orchards in natural conditions and at management technical level of Tai'an area, the tree structure and population structure of high-quality and high-yielding Y-shaped pear orchards were investigated. The results showed that when the yield of Y-shaped 'Oshu' was 2 550 kg/667 m^2 in the early fully fruiting period, the quantity of the branches per 667 m^2 was about 54 000, and the number of short branches was the largest, accounting for 80.1% of total number of branches, followed by middle branches, long branches and developmental branches. As the yield of Y-shaped 'Qiuyue' was 2 875 kg/667 m^2 in the early fully fruiting period, the quantity of the branches per 667 m^2 was 51 000, and the number of short branches was the largest, accounting for 75.6% of total number of branches, followed by middle branches, long branches and developmental branches. When the yield of Y-shaped 'Niitaka' was 3 000 kg/667 m^2 in the early fully fruiting period, the quantity of the branches per 667 m^2 was 43 000, and the number of short branches was the largest, accounting for 82.0% of total number of branches, followed by long branches, middle branches and developmental branches. 展开更多
关键词 PEAR y shape HIGH-QUALITy and HIGH-yieldING TREE structure parameters
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Effects of PVA and PEG on pH Dependent Shear Yield Stress of Concentrated Alumina Suspensions
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作者 曾人杰 B.RAND 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第1期132-133,共2页
The pH dependence of the extrapolated shear yield stress for Alcoa A16 a-Al2O3 suspensions at the powder volume fraction of 0.27 with and without addition of both polyvinyl alcohol (PVA) and polyethylene glycol (PEG) ... The pH dependence of the extrapolated shear yield stress for Alcoa A16 a-Al2O3 suspensions at the powder volume fraction of 0.27 with and without addition of both polyvinyl alcohol (PVA) and polyethylene glycol (PEG) each at fixed 0.18% of the powder mass was studied. With the polymer added, the full deflocculation of the suspension shifts from about pH=4 to around pH=1.5, at which the minimum value of shear yield stress is higher than that at pH=4. The addition of both PVA and PEG was found to prevent the filter cake from cracking. 展开更多
关键词 polyvinyl alcohol polyethylene glycol shearing yield stress pH value alumina suspension
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尿液蛋白激酶Y基因启动子位点甲基化在前列腺癌早期诊断中的价值
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作者 刘伟峰 戴政 +5 位作者 周毅彬 封凯文 魏恺 孙古乐 阳东荣 朱进 《实用医学杂志》 CAS 北大核心 2024年第5期688-694,共7页
目的 探讨尿液蛋白激酶(PRKY)基因启动子位点甲基化在前列腺癌(PCa)早期诊断中的临床价值。方法 收集50例疑似PCa患者的尿液,提取DNA后,通过定量甲基化特异性PCR(qMSP)法检测PRKY基因启动子位点cg05163709、cg08045599及cg05618150甲基... 目的 探讨尿液蛋白激酶(PRKY)基因启动子位点甲基化在前列腺癌(PCa)早期诊断中的临床价值。方法 收集50例疑似PCa患者的尿液,提取DNA后,通过定量甲基化特异性PCR(qMSP)法检测PRKY基因启动子位点cg05163709、cg08045599及cg05618150甲基化水平,同时将患者分为良性前列腺增生(BPH)组和PCa组,并分析两组患者临床指标差异以及两组患者尿液中的PRKY基因启动子位点甲基化状态。建立受试者工作特征曲线(ROC),计算曲线下面积(AUC),分析其在PCa中的诊断价值,并联合临床指标进行联合诊断。结果 PCa患者尿液标本中cg05163709和cg05618150甲基化率明显高于BPH患者,其中cg05163709甲基化诊断PCa的AUC为0.762,敏感度为86.70%。与前列腺特异性抗原(tPSA)等临床指标相比,PRKY甲基化在PCa早期筛查中表现更好。cg05618150甲基化与前列腺特异抗原密度(PSAD)联合诊断的AUC为0.787,敏感度为86.70%;cg05163709甲基化与PSAD联合诊断PCa的AUC为0.855,特异度为95.00%。结论 尿液PRKY基因启动子cg05163709和cg05618150位点甲基化在诊断PCa上具有较高的敏感度和特异度,有望成为PCa早期诊断的生物标志物。 展开更多
关键词 前列腺癌 尿液蛋白激酶y 早期诊断 甲基化 临床价值
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稀土Y对TiZrNb中熵合金组织及性能的影响
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作者 耿甜甜 李炳 +3 位作者 范新会 李想 李宗茂 谭本立 《铸造》 CAS 2024年第11期1506-1511,共6页
采用真空感应熔炼铸造的方法制备出TiZrNb、TiZrNbY_(0.25)和TiZrNbY_(0.5)三种中熵合金,研究了稀土元素Y对TiZrNb合金的组织结构、力学性能以及耐蚀性能的影响。结果表明,随着Y含量的增加,合金晶粒组织得到细化,成分更加均匀,但在枝晶... 采用真空感应熔炼铸造的方法制备出TiZrNb、TiZrNbY_(0.25)和TiZrNbY_(0.5)三种中熵合金,研究了稀土元素Y对TiZrNb合金的组织结构、力学性能以及耐蚀性能的影响。结果表明,随着Y含量的增加,合金晶粒组织得到细化,成分更加均匀,但在枝晶间形成了少量的富Y,富Zr及Ti_(4)Nb相。稀土Y的添加,提高了TiZrNb合金的压缩屈服强度,但TiZrNbY_(0.5)合金枝晶间析出较多强度较差的富Y相,其压缩屈服强度低于TiZrNbY_(0.25)合金。此外,Y元素提高了TiZrNb合金的耐蚀性能,TiZrNbY_(0.25)合金在1 mol/L HCl溶液中的腐蚀电流密度仅为4.71×10^(-7)A/cm^(2)。 展开更多
关键词 稀土y 中熵合金 显微组织 屈服强度 耐蚀性能
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Evaluating Added Benefits from Combined Cattle Manure and Fertilizer Application in a Maize Cropping System
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作者 Mavis Badu Brempong Andrews Opoku +1 位作者 Nana Ewusi-Mensah Robert Clement Abaidoo 《Journal of Environmental Science and Engineering(B)》 2017年第1期34-40,共7页
A field experiment was conducted at Kpongu in the Upper West region of Ghana to determine the added benefits in grain yield of maize derived from the concurrent use of manure and mineral fertilizer, and their cost eff... A field experiment was conducted at Kpongu in the Upper West region of Ghana to determine the added benefits in grain yield of maize derived from the concurrent use of manure and mineral fertilizer, and their cost effectiveness. Factorial combinations of cattle manure and mineral fertilizer each at 0, 50 and 100% of their recommended rates were evaluated in both the field and the laboratory studies. The treatments were applied in a randomized complete block design with three replications on the field. The same treatments were applied in the incubation study in a completely randomized design. The use of 100% NPK (Nitrogen, Phosphorus, Potassium) + 5 t manure gave the highest grain yield of 4,678 kg·ha^-1. Synergistic interactions resulting in added benefits in grain yield were observed in all the combined nutrient inputs except 50% NPK + 2.5 t manure which accrued an added disadvantage of 44 kg·ha^-1. Economic analysis proved that 100% NPK + 2.5 t manure and 50% NPK + 5 t manure were the most economically viable combined treatments in terms of grain yield. Based on the results from this study, resource poor farmers in the Upper West region of Ghana may reduce mineral fertilizer recommended rates by 50% and supplement it with 5 t quality (N 〉2.5%) cattle manure without compromising yield and profit. 展开更多
关键词 Synergistic interaction yield value cost ratio.
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