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果实(种子)产量和质量是影响植物种群更新的重要因素。为了探明影响黄连木果实产量和种子命运的因素以及这些影响因素之间的相互作用,作者于2009年对河南省济源市45株黄连木(Pistacia chinensis)结果样树的植株特征、果实特征、果实产量和种子命运等进行了测定,并用结构方程模型进行综合分析。结果表明:(1)黄连木果实产量与树高、树冠面积和果序大小等特征成正相关,但与胸径、果实大小相关性不显著;(2)与捕食者饱和假说的预测不一致,单株果实产量对黄连木广肩小蜂(Eurytoma plotnikovi)的种子捕食率(即虫蛀率)无显著直接负向效应;(3)树高和果实大小对虫蛀率为显著直接正向效应,胸径对虫蛀率为显著直接负向效应,显示黄连木广肩小蜂对植株特征和果实特征有一定的选择能力;(4)空壳率与虫蛀率成显著负相关,空壳果实越多,越易逃避黄连木广肩小蜂的寄生,空壳果实的存在对完好种子起到了一定保护作用,可能是黄连木防御昆虫寄生的重要机制;(5)空壳率和虫蛀率对种子完好率有显著直接负向效应,而胸径、果序大小和果实产量对完好率为间接正向效应,树高和果实大小为间接负向效应。可见,黄连木植株特征和果实特征均不同程度地影响其果实产量和昆虫寄生,从而影响黄连木的种子质量和种群更新。
Fruit (seed) yield and quality are important factors affecting plant population renewal. In order to find out the factors influencing the fruit yield and seed fate of Pistacia chinensis and the interaction between these factors, the author studied the plant characteristics, fruit characteristics, Fruit yield and seed fate were measured, and the structural equation model for a comprehensive analysis. The results showed that: (1) The fruit yield of Pistacia chinensis was positively correlated with the characteristics of tree height, canopy area and fruit size, but not with the DBH and fruit size. (2) The prediction was not consistent with the predator’s hypothesis, There was no significant direct negative effect of fruit yield on the seed predation rate (ie, moth-eaten rate) of Eurytoma plotnikovi. (3) The tree height and fruit size had a significant direct positive effect on the moth- The direct and negative effect on the rate of moth-earing showed that the Pistacia chinensis had a certain selection ability on plant characteristics and fruit characteristics; (4) There was a significant negative correlation between the percentage of empty shell and the rate of moth-eaten. , The easier it is to evade the parasite of Pistacia chinensis, the existence of shell fruit plays a protective role on intact seeds and may be an important mechanism of Pistacia chinensis in preventing insect parasitism; (5) The intact rate had a significant direct negative effect, while the DBH, fruit size and fruit yield had an indirect positive effect on the intact rate, and the tree height and fruit size were indirect negative effects. It can be seen that the plant characteristics and fruit characteristics of Pistacia chinensis affect the fruit yield and insect parasitism to varying degrees, thus affecting the seed quality and population renewal of Pistacia chinensis.