紫翅猪毛菜果实异型性及个体大小依赖的空间变化

紫翅猪毛菜（Salsolan affinis C．A．Mey）是藜科1年生植物，广泛分布于新疆准噶尔盆地，具有果实异型性现象。本研究在准噶尔盆地周缘选择了代表性的9个样点（种群），将野外调查与室内观测相结合，对比分析不同种群异型果实的形态特征，以及异型果实输出比例与植物大小的关系。结果表明：所有样点紫翅猪毛菜果实均存在异型性，但异型情况存在差异，其中6个样点有A、B、C、D4种类型，3个样点只有A、B、D3种。总体上来看，同一样点内的异型果实在果实直径、果实百粒重存在变化，其中A型果实在果实直径、果实百粒重上均显著高于其它类型。6个样点中的紫翅猪毛菜的A型果实所占比例明显大于其他3种类型，且与植株大小呈极显著的正相关，而B、C、D型果实所占比例与植株大小间大致呈负相关关系。表明该物种当生存条件有利时，倾向于“机会型”策略，产生较多扩散能力强、易于萌发的A型果实；生存条件不利时，倾向于产生扩散能力弱、不易萌发的B、C、D果实类型，采取较“保守型”繁殖策略。在准噶尔荒漠波动强烈的环境条件下，紫翅猪毛莱可以通过产生不同组合的异型果实及不同异型果实比例来提高环境适应性。

Salsola a f finis Heterocarpy and Size-Dependent Spatial Variation

Salsola a f finis is an annual plant, and widely distributed in Junggar Basin, Xinjiang, China. Our aim is to determine the morphological characteristics of heterocarpy fruits and relationship between size and yield of plants produced by them. Re- sults show that all of the Salsola affinis in this review have fruit heterocarpy,6 plots can produce 4 types of fruits,and the oth- ers are only three types of fruits. Overall,the different types of fruits have changed in the fruit size and weight. The fruits of type A are significantly higher than others on fruit size and weight. In 6 plots,there are more proportion of fruit type A than other types,and the proportion of fruit type A in an individual is positively correlated with plant size, while the proportion of three other fruit type is negatively correlated with plant size. This suggests that plants produce more fruits of type B,C, D with weakest dispersal ability and lower germination percentages in poor environment,while it produce more fruit type A with strong dispersal ability and higher germination in suitable environment. In the unpredictable environment of the Junggar Basin, plant size of Salsola affinis is closely related to micro-habitat. This species can reduce competition among siblings and increase adap- tive responses to different micro-environmental conditions by making full use of germination differences between peripheral and central achenes and regulating yield of both achenes in different plant sizes.