机灵的“土豆”

我有一个可爱的妹妹，今年7岁，因为她特别爱吃土豆，不知什么时候，大伙儿都亲切地叫她“土豆”了。“土豆”喜欢扎两条长长的辫子，大大的眼睛炯炯有神，她的胳膊腿儿胖乎乎的，一坐下来，就挤出一节节饱满的“莲藕”来，让人看了真想咬一口。

我家的“土豆”

我家的＂土豆＂是一只兔子,非常可爱。＂土豆＂这个名字可是我琢磨了半天才起的。 ＂土豆＂和其他兔子一样,有一双红色的眼睛,好像是被谁给气红的。长长的耳朵,高兴时竖得老高,生气时就垂了下来。它的鼻子小小的,嘴巴可奇怪了,分成了三瓣,就像一个奔驰的标志。＂土豆＂的毛是黑色的,摸上去毛茸茸的,很柔软。

信息存储空间提供者的版权侵权责任——以“土豆案”为视角

信息存储空间提供者的版权侵权责任是信息时代新传播技术冲击传统版权制度的激烈表现之一。本文以"土豆案"为视角,分析了信息存储空间提供者版权侵权的责任形态、责任构成,并审视了新技术与版权制度的未来发展方向。

“土豆”巴兰钦的音乐剧之旅（上）

巴兰钦是一位有着丰富芭蕾积淀的艺术大师，他不仅有着令人羡慕的“基洛夫”的资历，还有和现代派芭蕾制作人佳吉列夫4年合作的经历，可以说，巴兰钦在芭蕾艺术上的成熟得益于俄国芭蕾大师彼季帕的作品，而巴兰钦美学风格的建立则是从佳吉列夫时期开始的。巴兰钦知道芭蕾不仅能将人们带入童话世界，去“天鹅湖”寻找“睡美人”，它也能直探人类的内心世界，发掘人类的七情六欲；它还能反映伟大音乐的韵律和节奏，化音响为具体的形象，在肉体和情感上同时反映乐曲的内涵。这样一位舞蹈大师来到百老汇，可以说是上帝对百老汇的眷顾。

鼓励提问,把创新教育落到实处——从“土豆体积的计算”想到的

创造性活动是异常的行为 ,鼓励创造在教学工作中首先就得从鼓励学生提问着手 ,创设安全容忍的氛围 ,其次教师可以引导学生学会提问 ,培养讨论习惯 ,以触发创新思维 ,真正把创新教育落到实处 .

冈特·兰堡“土豆”系列招贴设计的符号学阐释

冈特·兰堡曾被誉为世界三大平面设计师之一,其招贴设计作品在国际上享有盛誉。本文以冈特·兰堡"土豆"系列招贴设计为研究样本,运用符号学研究范式中"符号阐释的空间"理论探索招贴设计中作者、语境、文本、读者四个阐释维度的相互关系和招贴设计图像与符号的意蕴结构。

土豆牛肉的分与合

提起土豆与牛肉，许多人会联想到“土豆烧牛肉”的故事。在20世纪60年代，几乎人人都知道前苏联领导人赫鲁晓夫的著名政治笑话——“土豆烧牛肉”式共产主义，可能还背诵过毛泽东在《念奴娇·鸟儿问答》中通俗并且很有气魄的批判词句：“土豆烧熟了，再加牛肉。不许放屁，试看天地翻覆。”但是，却很少有人明白“土豆烧牛肉”到底是怎么回事。

Influence of functionalized graphene on the bacterial and fungal diversity of Vicia faba rhizosphere soil

The effect of functionalized graphene on the growth and development of Vicia faba L.was investigated by analyzing its impact on the composition and diversity of the microbial community in rhizosphere peat soil.Seedlings of V.faba planted in this peat soil were treated with either distilled water(CK)or 25 mg·L^(−1)(G25)of functionalized graphene solution.Results showed that the height and root length of V.faba seedlings in the G25 group were significantly larger than those in CK group.The microbial com-munity was analyzed by amplifying and sequencing the 16S rRNA gene V_(3)-V_(4) region of bacteria and internal transcribed spacer re-gion of fungi in rhizosphere soil using Illumina MiSeq technology.Alpha and beta diversity analysis indicated that functionalized graphene increased the richness and diversity of bacteria and fungi in the V.faba rhizosphere peat soil.The abundances of three ni-trogen cycling-related bacteria,Hydrogenophaga,Sphingomonas and Nitrosomonadaceae,were also altered after treatment with the functionalized graphene.The relative abundance of Basilicum,related to soil phosphorus solubilization,decreased in the fungal com-munity,while the relative abundance of Clonostachys and Dimorphospora,which exhibited strong biological control over numerous fungal plant pathogens,nematodes and insects,increased in the soil after functionalized graphene treatment.Redundancy analysis re-vealed that the potential of hydrogen(pH),organic matter,and total phosphorus contributed the most to the changes in bacterial and fungal community composition in the rhizosphere soil.Overall,our findings suggested that the addition of functionalized graphene altered the relative abundances of nitrogen and phosphorus cycling-related microorganisms in peat soil,promoting changes in the physicochemical properties of the soil and ultimately leading to the improved growth of V.faba plants.

Analysis on Waxy Corn/Soybean Intercropping Pattern and Economic Benefit

The research mainly analyzed effects of waxy corn/soybean intercropping on yields of the two crops, as well as agronomic characters, and the economic benefits of the mode. The results showed that although yields of waxy corn and soybean went down by 21.19% and 31.04% per unit area, land equivalent ratio（1.48） kept higher than 1, suggesting the intercropping improves land use rate. Besides, due to the practice of intercropping, many characters of waxy corn grew, but of soybean declined. The economic benefits from high to low were waxy corn/soybean intercropping, monoculture of waxy corn, and monoculture of soybean.

Effects of Nitrogen Fertilization Amount on the Prophase Yield of Phaseolus vulgaris and Available Nitrogen Content of Soil

[Objective] This study aimed to provide certain scientific basis for reasonable application of nitrogen fertilizer in the pollution-free cultivation of Phaseolus vulgaris. [Method] A field experiment was conducted to investigate the effects of different nitrogen fertilization amounts on the prophase yield and economic efficiency of P. vulgaris and available nitrogen content of soil. [Result] With the increased application amount of nitrogen fertilizer, the prophase yield and economic efficiency of P. vulgaris reached the peaks in the Treatment 3 （8 690.48 kg/ hm^2 and 32 222 yuan/hm^2）, and significant differences were found among different treatment groups. With the increased nitrogen fertilization amount, the soil available nitrogen content increased, showing a positive correlation with correlation coefficient of 0.856 5. Excess nitrogen fertilizer reduced the prophase yield and economic efficiency of P. vulgaris. For the open field cultivation of P. vulgaris, the optimum application amount of nitrogen fertilizer was 178 kg/hm^2. [Conclusion] Application of nitrogen fertilizer could effectively increase the soil available nitrogen content.

Tomato Leaf Photosynthetic Responses to Humidity andTemperature Under Salinity and Water Deficit

Greenhouse tomato plants (Lycopersicon esculentum Mill cv. Capello) were grown on peat-based substrate and treated with high (4.5 mS cm-1) and low (2.3 mS cm-1) nutrient solution electric conductivity(EC) under high and low substrate water contents. FOur weeks after the beginning of the treatments, photosynthesis (Th) was measured under different humidity and temperatures to examine the interactive effectswith rhizosphere salinity and water deficit. A rectangular hyperbolic model fitted the light-photosynthesiscurve. Photosynthetic capacity (PC) was decreased but quantum yield (YQ) was increased by rhizospheresalinity caused by high EC. PN was decreased by low humidity only in high EC- and/or water-stressed plants.Under high photosynthetic photon flux (PPF), low humidity induced PC decline in water-stressed plants andPN oscillation in high-EC-treated plants. PN increased steadily as the leaf temperature changed from 18 Cto 23 and then decreased steadily from 23 to 38 . At 34 , PN decreased significantly in waterstressed plants. Dark respiration (RD) increased in an exponential manner as the leaf temperature changedfrom 18 to 38 to an extent about ten times higher under 38 than under 18 . Our data suggestedthat PN decrease under high temperature was attributed, st least in part, to the increased RD. RD in highEC- and/or water-stressed plants was higher than that in the plants of control under lower temperature butlower than that in the plants of control under high temperature. The analysis of stomatal and mesophyllconductance showed that low humidity effect was mainly through stomatal response while temperature effectwas mainly through biochemical functions. The result showed that environmental stresses affected PN in anadditive or synergistic manner.

Nutrient Balance in Relation to High Yield and Good Quality of Potato on an Acid Purple Soil in Chongqing,China

A field experiment was carried out to study nutrient balance among N, P, K and Mg in potato cultivation on an acid purple soil in Chongqing, China. The experiment included 8 treatments with equal P rate of 120 kg P2O5 hm-2: N0K2, N1K2, N2K2, N3K2, N2K0, N2K1, N2K1Mg and N2K3, where N0, N1, N2 and N3 stand for the N rates of 0, 75, 150 and 225 kg N hm-2, and K0, K1, K2 and K3 for the K rates of 0, 165, 330 and 495 kg K2O hm-2, respectively. Among the treatments designed, Thatment N2K2 with a nutrient supply ratio of N:P2O5:K2O:MgO = 1.25:1:2.75:0.28 gave the highest tuber yield and dry matter, highest starch and Zn and lowest NO3- contents in tuber, and high N, P and K use efficiency with an uptake ratio of N:P:K:Mg = 11.38:1:13.32:0.33 by tuber. Yield and starch and protein contents of tuber were the lowest in Treatment N0K2. Dry matter was the lowest but protein and NO3- contents were the highest in Treatment N2K0. Treatment N2K1Mg had the highest N, P and K utilization rates. Statistical analysis showed that yields of tuber and starch were in a positive linear correlation with the uptake amount of various nutrients and protein of the potato tuber was in a significantly positive linear correlation with tuber N cotent and in a significantly negative linear correlation with tuber K and Mg contents. Balanced application of N, P, K and Mg fertilizers (Treatmeat N2K2) was recommended for realization of high yield and good quality in potato cultivation.

Movement and Degradation of Metolachlor and Metribuzin in North Central Sand Region of Minnesota Under Irrigated Potato Production

Field studies were conducted to determine the dissipation and movement of metribuzin and metolachlor applied at conventional rates to a Verndale sandy loam (Udic Argiboroll) in north-central Minnesota under irrigated potato production in two years. The rapid dissipation of both metribuzin and metolachlor was found during the initial 10 to 15 days in both years) and more than 70% of the applied herbicide dissipated during this period. From 10 to 15 days after application up to the end of growing season in both years, the levels of both herbicides decreased slowly with time. Metolachlor dissipated at a slower rate than metribuzin in surface soil and could carry over to the next cropping season. Metribuzin and metolachlor were detected in only 6 and 1 of 154 soil samples in the first year and in 3 and 4 of 225 soil samples in the second year, taken from 15 to 75cm, respectively. Fifty to 67% of water samples from suction samplers at 135-cm depth contained detectable levels (>0.4μg L-1 ) of herbicides in both years. Under laboratory conditions degradation of both herbicides was much slower than their dissipation in field. Therefore, it appeared that leaching might be an important dissipation pathway for metribuzin and metolachlor under irrigated potato production.

Nodule Formation and Development in Soybeans(Glycine max L.) in Response to Phosphorus Supply in Solution Culture

Phosphorus (P) is necessary for growth and nitrogen fixation, and thus its deficiency is a major factor limiting legume production in most agricultural soils. The effect of phosphorus supply on nodule development and its role in soybeans (Glycine max L.) was studied in a nutrient solution. Plants were inoculated with Bradyrhizobium japonicum and grown for 35 days in a glasshouse at a day and night temperature of 25℃and 15℃, respectively. Although increasing P supply increased the concentrations of P and N in the shoots and roots, the external P supply did not significantly affect the P concentration in the nodules, and the N fixed per unit nodule biomass decreased with increasing P supply. The nitrogen content in the shoots correlated well with the P content (r = 0.92**). At an inoculation level of 102 cells mL-1, the P supply did not affect the number of nodules; however, at inoculation levels of 103.5 and 105 cells mL-1, increasing P supply increased both the number and size of nodules. Irrespective of the inoculation level, increasing P supply increased the nodule biomass relative to the biomass of the host plant. It is suggested that the P deficiency specifically inhibited the nodule development and thereby the total N2 fixation.

Tolerance of VA Mycorrhizal Fungi to Soil Acidity

A 45-day greenhouse experiment was carried out to determine effect of vesicular-arbuscular (VA) mycorrhizal fungi on colonization rate, plant height, plant growth, hyphae length, total Al in the plants, exchangeable Al in the soil and soil pH by comparison at soil pH 3.5, 4.5 and 6.0. Plant mung bean (Phaseolus radiatus L.) and crotalaria (Crotalaria mucronata Desv.) were grown with and without VA mycorrhizal fungi in pots with red soil. Ten VA mycorrhizal fungi strains were tested, including Glomus epigaeum (No. 90001), Glomus caledonium (No. 90036), Glomus mosseae (No. 90107), Acaulospora spp. (No. 34), Scutellospora heterogama (No. 36), Scutellospora calospora (No. 37), Glomus manihotis (No. 38), Gigaspora spp. (No. 47), Glomus manihotis (No. 49), and Acaulospora spp. (No. 53). Being the most tolerant to acidity, strain 34 and strain 38 showed quicker and higher-rated colonization without lagging, three to four times more in number of nodules, two to four times more in plant dry weight, 30% to 60% more in hyphae length, lower soil exchangeable Al, and higher soil pH than without VA mycorrhizal fungi (CK). Other strains also could improve plant growth and enhance plant tolerance to acidity, but their effects were not marked. This indicated that VA mycorrhizal fungi differed in the tolerance to soil acidity and so did their inoculation effects. In the experiment, acidic soil could be remedied by inoculation of promising VA mycorrhizal fungi tolerant of acidity.

Soil Respiration During a Soy bean-Growing Season

Soil respiration induced by soybean cultivation over its entire growing season and the factors influencing soil respiration were investigated to examine the seasonal pattern of soil respiration induced by soybean cultivation, explore soybean growth and photosynthesis on soil respiration, and determine the temperature dependence on soil respiration. Soil respiration in a pot experiment with and without soybean plants was sampled using the static chamber method and measured using gas chromatograph. Air temperature was a dominant factor controlling soil respiration rate in unplanted soil. Additionally, rhizosphere respiration comprised 62% to 98% of the soil respiration rate in the soybean-planted soil varying with the soybean growth stages. Harvesting aerial parts of soybean plant caused an immediate drop in the soil respiration rate at that stage. After harvesting the aerial parts of the soybean plant, a highly significant correlation between soil respiration rate and air temperature was found at the flowering stage （P 〈 0.01）, the pod stage （P 〈 0.01）, and the seed-filling stage （P 〈 0.05）. Thus, rhizosphere respiration during the soybean-growing period not only made a great contribution to soil respiration, but also determined the seasonal variation pattern of the soll respiration rate.

Temporal and Spatial Dynamics of Bacterial Community in the Rhizosphere of Soybean Genotypes Grown in a Black Soil

The dynamics of rhizosphere microbial communities is important for plant health and productivity, and can be influenced by soil type, plant species or genotype, and plant growth stage. A pot experiment was carried out to examine the dynamics of microbial communities in the rhizosphere of two soybean genotypes grown in a black soil in Northeast China with a long history of soybean cultivation. The two soybean genotypes, Beifeng 11 and Hai 9731, differing in productivity were grown in a mixture of black soil and siliceous sand. The bacterial communities were compared at three zone locations including rhizoplane, rhizosphere, and bulk soil at the third node （V3）, early flowering （R1）, and early pod （R3） stages using polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DCGE） of 16S rDNA. The results of principal component analyses （PCA） showed that the bacterial community structure changed with growth stage. Spatially, the bacterial communities in the rhizoplane and rhizosphere were significantly different from those in the bulk soil. Nevertheless, the bacterial communities in the rhizoplane were distinct from those in the rhizosphere at the V3 stage, while no obvious differences were found at the R1 and R3 stages. For the two genotypes, the bacterial community structure was similar at the V3 stage, but differed at the R1 and R3 stages. In other words, some bacterial populations became dominant and some others recessive at the two later stages, which contributed to the variation of the bacterial community between the two genotypes. These results suggest that soybean plants can modify the rhizosphere bacterial communities in the black soil, and there existed genotype-specific bacterial populations in the rhizospbere, which may be related to soybean productivity.

Ecotoxicity of Cadmium to Maize and Soybean Seedling in Black Soil

Ecotoxicity and bioavailability of cadmium （Cd） to the maize （Zea mays L.） and the soybean （Glycine max （L.） Merr.） were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity and bioavailability of Cd were quantified by calculating the median effective concentration （ECs0） and bioaccumulation factor （BAF）. The measurement endpoints used were seed germination and seedling growth （shoot and root）. The results showed that concentrations of Cd in the soil had adverse effect on the growth of roots and shoots. Seed germination was not the sensitive indicator for the ecotoxicity of Cd in the soil, while the growth of roots was the most sensitive measurement endpoint. Absorbability and transport of Cd in plants depended on the test crop species and Cd concentrations in the soil. The maize retains more Cd in its roots, while the soybean transports more Cd to the shoots from roots.