Photoperiodic termination of diapause in spider mites
Photoperiodic termination of diapause in spider mites
复制标题
红蜘蛛滞育的光周期终止
作者：
A. Veerman
蜘蛛叶螨滞育的终止被认为完全取决于冷冻期，即所谓的冷静期1-3。重新激活一定比例的越冬种群所需的最短冷冻期在不同地理来源的种群之间可能有所不同。然而，寒冷期和纬度之间并没有建立明确的关系，因为来自邻近地区的菌株之间的最小冷休息期可能存在明显的差异5。在Dubynina发现这一物种的一种俄罗斯品系的重新激活随着时间的推移而线性增加后，情况似乎更加复杂，当在漫长的白天、突然的温度变化和对食物的激烈竞争的影响下诱导螨类滞育时，重新激活是周期性的，而当短天数和相对较低的温度诱导滞育时，重新激活是周期性的。冷藏滞育40d和75d后，滞育雌虫复活百分率最高，50d和95d后复活百分率最低，105d左右复活完成。然而，在英国的实验没有证据表明英国的麻风杆菌株5周期性地重新激活。使用一种荷兰的麻风菌菌株，该菌株具有恒定的光周期反应，并已在实验室饲养了15年以上(参考文献)。7)，我们现在发现，该物种滞育的终止不仅取决于冷期，还取决于光周期。
TERMINATION of diapause in the spider mite Tetranychus urticae is considered to depend solely on a period of chilling, the so-called cold rest1–3. The minimal period of chilling required to reactivate a certain percentage of the overwintering population may vary between populations of different geographic origin4. No unambiguous relationship, however, has been established between chilling period and latitude, for there may be appreciable differences in the minimal period of cold rest between strains from close localities5. The situation seemed more complex after Dubynina's6 discovery that reactivation of a Russian strain of this species increased linearly with time when mites had been induced to diapause under the influence of long days, abrupt temperature changes and severe competition for food, while reactivation was cyclical when diapause had been induced by short days and relatively low temperatures. In the latter case maximal percentages of reactivating females were obtained after diapausing mites had been kept in cold storage for 40 and 75 d. Minimal percentages were obtained after 50 and 95 d. Reactivation was complete by about the 105th day of storage. Experiments in England, however, produced no evidence for cyclical reactivation in British strains of T. urticae5. Using a Dutch strain of T. urticae, which has a constant photoperiodic reaction and has been reared in the laboratory for more than 15 yr (ref. 7), we have now found that termination of diapause in this species depends not only on a period of chilling but on photoperiod as well.