| 1. | Economic threshold for the control of apple fruit borer
桃小食心虫的防治标准 |
| 2. | Economic threshold of the rice stem borer
水稻二化螟防治标准 |
| 3. | The experiment was conducted to estimate the economic injury level ( eil ) and economic threshold ( et ) of b . tabaci
摘要研究了烟粉虱在黄瓜上的经济损害水平和经济阈值。 |
| 4. | Preliminary study on occurring regulation of henosepilachna vigintioctomaculata in yulin area and its economic thresholds
榆林地区马铃薯二十八星瓢虫发生规律及防治指标初步研究 |
| 5. | Relationship between the population density of schizotetranychus nanjingensis with the bamboo output and the determination of economic threshold
南京裂爪螨种群密度与新竹产量的关系及经济阈值的研究 |
| 6. | Maximum economic yield programs require research that develops economic thresholds for the need to apply disease control measures , . especially excessive amounts of tillage and the use of fungicides
最大经济产量研究中，必需为必要防病措施制定一个经济阀值，避免耕地次数过多或施用杀真菌剂过多。 |
| 7. | Via investigation and analysis , it discussed relation between occurrence of wheat yellow dwarf and yield . morbidity and grades standard was determined as well as wheat dwarf economic threshold
摘要通过系统调查与分析，探索了小麦黄矮病的发生程度与产量的关系，确定了其发病程度与分级标准，研究出了小麦黄矮病的经济阈值。 |
