关键词: 潜在产量, 可获得产量, 东北三省, 玉米, 农户潜在产量, 农户实际产量

Abstract: Fast-start is one of the important swimming modes, which is closely related to predation and escape behaviors in fish species. The aims of the present study were to compare the effects of food deprivation on fast-start swimming performance between a predator Channa argus and a prey Pseudorasbora parva and the consequent outcome of predatorprey interaction. To achieve our goals, variables related to faststart swimming were measured in C. argus after 0, 7, 14, 28, 63 (semilethal starvation time) days of starvation and P. parva after 0, 7, 14 (semilethal starvation time) days of starvation under water temperature of (25±1) ℃. The predationprey interaction course was also documented after 0, 7 and 14 days of starvation. The results showed that C. argus showed  significantly higher maximum linear velocity (V_max), moving distance during first 120 ms (S_120ms) and maximum linear acceleration (A_max) than P. parva (P<0.05), whereas their reaction latency (R) showed no significant difference. All measured variables of fast-start swimming in both fish species were quite conservative as only the semilethal group (14 or 63 days) showed significantly lower V_max, shorter S_120ms and slower R (P<0.05), with the predator showing relatively profound change in R and the prey showing relatively profound change in V_max. Fourteen days of starvation resulted in more hunting activities of the predator and shorter duration while hunting successfully. The present study suggested that the faststart swimming of the prey was more sensitive to starvation than that of the predator and the two species showed different response strategies possibly due to differences in availability of food resources and foraging modes. In general, starvation with the same degree would be more beneficial to the predator according to the outcome of predatorprey interaction.

Key words: attainable yield, potential yield, Northeast China, potential farmers&rsquo, yield., maize, yield, actual farmers&rsquo