马尾松种子园交配系统的时间动态变异

以马尾松种子园不同时期(建园初期、丰产期及衰老期)产出的子代为材料,采用SSR标记分析其遗传多样性,并结合子代测定数据分析交配系统对子代遗传品质的影响。研究结果表明,建园初期与丰产期的子代家系的Shannon多样性指数(I)较高,同为0.53,衰老期的子代家系则为0.47。观测杂合度(Ho)和期望杂合度(He)均以建园初期子代群体为最高,丰产期子代次之,衰老期最低。马尾松种子园建园初期与丰产期的子代均具有较高的遗传多样性。丰产期参与繁殖的父本数量最多,近交水平较低,从而保证了种子的品质。而种子园衰老期子代的遗传多样性明显下降,说明种子园的老化不仅影响种子产量,而且影响种子遗传品质。在亲本分析中,种子园建园初期、丰产期及衰老期的子代均未检测到自交情况。由此可进一步证实马尾松是典型的异交树种。

Temporal Variation of Mating System in A Seed Orchard of Pinus massoniana

We studied the influence of mating system to the quality of the offspring which was based on the Masson pine seed orchard from different period (at the beginning period, high yield period and aging period), SSR markers for genetic diversity and progeny test data of offspring.At the beginning and high yield period, the offspring Shannon diversity index (I) was high, both values were 0.53, and at the aging period was 0.47.The observed heterozygosity (Ho) and expected heterozygosity (He) of the offspring population was highest at the beginning period followed by high yield period, and the aging period was the lowest.Offspring from the beginning period and high yield period of seed orchard of Masson pine had high genetic diversity.In high yield period, the number of male reproductive participation was the largest, and inbreeding level was low, so as to ensure the quality of the seeds.The genetic diversity of offspring was significantly decreased at the aging period, which meant that the aging of seed orchard affected the seed yield and the genetic quality of the seed.In the parent analysis, inbreeding was not detected in offspring at the beginning, high yield and aging period.The Masson pine is a typical outcrossing species.