查询词典 yield gap

Meteorologic data and rice yield data were analyzed in Xinyang from 1991 to 2004, and the reason of yield's decreasing was intense change of sunlight and temperature from July to September, and the rice yield was reduced by 28.28% compared with average of recent five years.

通过对信阳地区1991—2004年的气象数据和水稻产量数据的分析，发现2003年水稻的减产是由于7—9月光温条件的剧烈变化所造成，产量相比近五年平均（2000—2004年）降低了28.28%。

Bis-imidazoline was prepared from triethylene tetraamine and N,N-dimethylformamide dimethyl acetal at 85℃ for 2 h with toluene as solvent, with a yield of 90.4%. The reaction of bis-imidazoline with 1,2-dibromoethane and potassium carbonate in acetonitrile provided with a monobromide salt yield of 78.7%. Hydrolysis of monobromide salt under aqueous causic solution formed 1,4,7,10-tetraazzcyclododecane in a 74.2% yield.

用甲苯作溶剂，使三乙烯四胺和N，N-二甲基甲酰胺二甲基缩醛在85℃反应2 h，得到中间体双咪唑啉，产率90.4%，在乙腈溶剂中，碳酸钾存在下，双咪唑啉和1，2-二溴乙烷进行扩环反应，得到环状中间体一溴盐，产率78.7%，一溴盐经碱性水解2 h，得到1，4，7，10-四氮杂十二烷，产率74.2%。

In order to provide theoretical basis and technological for high-quality and high-yield cultivation of a strong gluten wheat variety,Jimai 20,the experiment studied effects of the radio of nitrogenous fertilizer and potassic fertilizer on yield and qualitly of Jimai 20 under the field conditions with High-yield cultivation.

为了给强筋小麦品种济麦20优质高产配套栽培提供理论依据及技术支撑，在大田高产栽培条件下，研究了氮钾肥施用量及其配比对强筋小麦品种济麦20产量和品质的影响。

The final yield showed that the yield of plastic ridging and furrow drilling increased yield of conventional flat planting 1472.10 kg/hm^2, increased by 19.3%; increased 1844.79 kg/hm^2 compared with ridging and furrow drilling, increased by 25.4%, differences between different treatments were up to super remarkable level.

最终产量测定，起垄覆膜沟播冬小麦极显著的高于传统平作，比传统平作栽培高1472.10 kg/hm^2，增产幅度19.3%；比起垄沟播冬小麦最终产量高1 844.79 kg/hm^2，增产25.4%，差异均达到极显著水平。

The thermal property studies indicate that the mass loss of compound B was 54.39% at 242.2~750℃, and when the temperature was 1000℃, there was 25.11% char residue left, which showed that the title compound has a good thermal stability and char forming capability. Using acetonitrile as the solvent instead of trichloromethane or 1, 2-dichloethane gave higher yield. During the synthesis, the yield was very low when triethylamine was used as acid acceptor alone, and when a little amount of 4-dimethylaminopyridine was added at the same time, the yield could be 81%.

结果表明，所合成的化合物B的结构与预期的结构一致；热性能研究表明，化合物B在242.2~750℃质量损失为54.39%，1000℃时仍有25.11%的炭残渣，显示出优异的热稳定性和成炭性；在相同反应条件下，用乙腈作为溶剂的反应产率比使用氯仿和二氯乙烷为溶剂的高，并且在合成过程中，单独使用三乙胺作为缚酸剂时产率很低，而当同时加入少量4-二甲氨基吡啶时，产率可达81%。

The result shows that the 0503 ripes earlier and suits to be a cultivar of Zizania caduciflora reaped earlier than usual in spring. The 0501 also ripes a little earlier, so the 0503 and the 0501 both suit to be cultivars of Zizania caduciflora reaped earlier than usual in autumn. The 0504, the 0505 and the 0506 all have high yield, in some special situation they can be planted in flowing cold water or planted in high hills to harvest earlier in fall. Thought of the reap time, the yield, the quality of the appearance and the quality of the nutrition, the 0504, the 0505 and the 0506 have high yield and high quality, which can be spread and exported.

结果认为双季茭0503具有早熟特性，适宜作为春早熟栽培品种；单季茭0501也具有较早成熟的特性，和0503均适宜作为露地秋早熟栽培品种，而较为丰产的0504、0505、0506在条件允许时可以进行冷水栽培或高山种植，实现秋早熟；综合熟期、产量、外观品质、营养品质等各方面进行比较，认为0504、0505和0506丰产优质，适宜常规种植推广，并可出口创汇。

This paper based on Precision Agriculture development of China, and focused on several key problems for developing Precision Agriculture, especially field spatial information distribution processing method. The trail farm is located in Shunyi, Beijing. The area is 11 hectors. We sampled the soil, and got soil spatial distribute data , crop growing status distribute data (such as crop population, crop height, plant dry weight), yield distribute data (such as yield per mu, ears per mu, seeds number per ear, weight of thousand grain, plant yield).

本文在探索我国精细农业发展道路的基础上，以当前开展精细农业实践急需解决的关键问题之一—农田空间分布信息处理方法研究作为切入点，通过对北京顺义&三高&农业示范区一块面积约11公顷的农田进行了定点采样试验，得到土壤空间分布信息、苗情分布信息（株数、株高、地上干物重等）、产量分布信息（亩产量、亩穗数、穗粒数、千粒重、生物产量等）。

It showed that this mode was better than "beyond high yield mode" though lower in yield. Farmers evaluated this mode overmatching normal mode except for difficulty in technology and intensity in labor. Sparse 、 manipulative 、 weight middle season rice high yield in the middle of

轻简化栽培模式在沙洋县大田试验产量达到613kg／667m~2，比常规栽培增产4.6％；纯收入达到288.22元／667m~2，比常规栽培多147.98元；农民对该模式的评价是劳动强度小，技术上较容易，有一半的农户认为经济收益好，其它指标优。

The results showed:Under the same fertilizer consumption,covered with straw and covered with film can increase the chlorophyll content and total leer area duration of the maize,can improve leaf nitrate reeducates activity,Photosynthesis and roots vigor,and the nitrate reeducates activity,the chlorophyll content and the roots vigor present positive correlation with yield. Meanwhile,average dry matter accumulation of straw-covered increased 7.1% than this of no-ploughed,yield increased 15.3%.The average dry matter accumulation of film-covered increased 20.1% than which of no-ploughed and 12.1% than which of plough and covered with straws.And yield increased 26.8% and 10.1%,notable differences.

结果表明：在相同的肥料用量条件下，秸秆覆盖和薄膜覆膜对玉米生长发育具有良好的促进作用，能显著增加玉米叶片叶绿素含量和光合势，增强叶片硝酸还原酶活性和根系活力，同时玉米叶片硝酸还原酶活性、叶绿素含量、根系活力等与最终籽粒产量呈正相关；秸秆覆盖比免耕全生育期平均单株干物质积累量增加7.1%，籽粒产量增加15.3%，薄膜覆膜分别比免耕和翻耕残茬覆盖全生育期平均单株干物质积累量增加20.1%和12.1%，最终籽粒产量增加26.8%和10.1%，差异显著。

5The height, length of leaves, width of leaves, fresh weight of single plant, fry matter weight of single plant, leaf areas of single plant, LAI, yield of single plant and yield components were reduced during drought stress at different growth stages. The decreased percent was the most great to grains per corncob at tasseling drought stress; hundred-grain-weight, at grain stage drought stress; yield of single plant, at booting-blossoming, and the extent was

不同生育时期干旱胁迫处理春玉米株高、平均叶片长度、平均叶片宽度、单株鲜重、单株干重、单株叶面积、叶面积指数、产量及产量构成因子均有不同程度下降。

You'll be in trouble it you don't watch out .

如果你不注意，你会有麻烦的。

Shaped like a biconvex lens.Of, relating to, or having the form of a hyperbola.

双曲线的属于双曲线的，与之有关的，或有双曲线形状的