华山松球果对食种子动物的防御特征

动植物协同演化过程中,植物为抵御捕食者的侵害,保证自身的生存和繁衍,会演化出不同方式的防御机制。本研究调查了星鸦对藏东南地区华山松弯曲球果上不同部位种子取食的差异性,并检测了华山松球果凹凸面种子的形态特征(长度、宽度、厚度、种壳厚度)和成分(粗水分、70 ℃干物质、粗脂肪、灰分、蛋白质、粗纤维)含量。结果表明: 华山松球果凹凸两面种子的部分形态特征和种子成分具有显著差异,其中,凸面种子种壳厚度(1.11±0.12 mm)比凹面种子(1.07±0.15 mm)厚,但种仁重占比凸面(24.0%)比凹面(25.4%)小。而凸面种子空壳率(11.2%)和种子成分中粗脂肪含量(47.0%)显著低于凹面种子(分别是15.8%和50.5%)。华山松弯曲球果对食种子动物取食造成错误性暗示,尽可能保护优质种子不被取食,因此球果弯曲是华山松对食种子动物的防御特征。

Defensive characteristics of cones of Pinus armandii against seed-eating animals

During the co-evolution with animals, plants evolved different defense strategies to resist predators and ensure their own survival and reproduction. We investigated the forging preference of nutcrackers (Nucifraga caryocatactes) for seeds in different parts of bending Pinus armandii cones in Southeast Tibet. We measured the morphological characteristics (length, width, thickness, and seed hull thickness) and the physical and chemical properties of concave and convex seeds of P. armandii (crude water, dry-matter at 70 ℃, crude fat, ash, protein and crude fiber). The results showed that there were significant differences in seed shell thickness, kernel percentage and empty shell percentage between the concave and convex seeds. The seed shell thickness of convex seeds (1.11±0.12 mm) was thicker than that of concave seeds (1.07±0.15 mm). The kernel weight percentage of convex seeds (24.0%) was smaller than that of concave seeds (25.4%). The empty shell percentage (11.2%), crude fat content (47.0%) of convex seeds were significantly lower than that of concave seeds (15.8% and 50.5%). The curving cones of P. armandii cause false hints to seed eaters, and protect high-quality seeds from being eaten as much as possible. Therefore, the curving cone is a defensive characteristics of P. armandii against seed predators.