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- average crop yield 农作物平均产量
- Crop yield correlates closely with annual rainfall. 农作物的收成与年降雨量有密切关系。
- Ways of Improving Crop Yield Per Unit Area and the Countermeasures. 提高作物单产的途径与对策。
- The study of plant nutrition and growth as related to soil condition, especially to determine ways to increase crop yield. 农业生物学; 土壤生物学关于植物养分和与土壤条件相关的生长的研究，尤其是对判定如何增加农作物产量方法的研究
- Blackened circles denote accumulated temperatures and open ones crop yield. 涂黑圆圈表示积温,空白圆圈表示作物产量。
- The crop yields for the year are phenomenal. 当年的庄稼产量是惊人的。
- USDA analysts continue to work on details for the Average Crop Revenue Election (ACRE) program as signup for the 2009 Direct and Counter-cyclical Program (DCP) moves forward. 随着2009年直接补贴和反循环补贴报名登记的推进，美国农业部分析师们正在继续深入研究作物平均收入备选方案的细节问题。
- Effect of long-term single application of chemical fertilizer on soil properties and crop yield. 长期单施化肥对土壤性状及作物产量的影响。
- Effects of rice straw mulch and water-retaining agent on soil properties and crop yield. 施用保水剂和稻草覆盖对作物和土壤的效应。
- N2O is a gas released by ammonium nitrate, which is widely used as a fertilizer to increase crop yield. N2O是由硝酸铵释放出来的气体,硝酸铵是一种广泛使用的化学肥料用于增加农作物的产量。
- Effect of plastic film mulching on crop yield and nitrogen efficiency in semiarid areas. 半干旱地区地膜覆盖对作物产量和氮效率的影响。
- Ex perimental results also indicated that sprinkler uniformity had little effect on crop yield for the studied range of CU. 试验结果还表明，在所研究的喷灌均匀系数范围内，均匀系数对产量的影响不明显。
- Vegetation Indies (VI) have been used to estimate crop yield and monitor crop growth for many years. 地表具有各项异性的特征，在监测地表植被时，经过大气纠正的数据，通过多时相和多角度合成时对于它的二向反射率必须经过角度归一化。
- The seed bourgeon ,seedling growth ,crop yield and heavy metals contents were influenced by contaminated soil. 土壤重金属污染影响了种子萌发、幼苗生长、作物产量及体内重金属含量,探讨了污染土壤的酶学评价方法。
- How to break crop yield stagnation is a serious question warranting an explanation. 如何打破作物产量徘徊的局面是应找到答案的一个严重问题。
- Fertilizer has a large influence on increasing crop yield, following practices, however, should be focused on MYR. 在高产研究中，充分发挥肥料的作用仍然是一项重要措施。目前应当注意以下几个问题。
- The relation between crop water use efficiency and crop productivity potential,crop yield were investigated. 研究了作物水分利用效率与作物生产潜力、产量的关系。
- Coupling remote sensing data with crop growth models to predict crop yield is a hot research topic. 将遥感信息与作物生长模式结合来预测作物产量,是目前的一个热点研究课题。
- On the other hand long-term no fertilization could make the crop yield at a lower level. 长期不施肥则导致作物产量维持在较低的水平。
- Heterosis is a common phenomenon in biological kingdom and plays an important role in increasing crop yield. 杂种优势是生物界普遍存在的现象，利用杂种优势是提高作物产量的一条重要途径。
