Effects of maternal nutrient and water availability on seed production, size and germination of heterocarpic Atriplex aucheri

摘要

Atriplex aucheri, which can be used as fodder, is a heterocarpic plant producing three types of fruits and seeds. The main aim of this study was to investigate the effects of maternal nutrient and water availability on changes in the mean value and within-cohort variation in seed production, seed size and germination of Atriplex aucheri seeds. Application of high levels of nutrients and water increased seed yield, but did not affect allocation to each seed type. Both nutrient and water treatments had significant effects on size of brown seeds and germination of small and large black seeds. Seed yield and seed size exhibited the greatest variation under high water availability and low or moderate nutrient levels. Brown seeds had the highest size, germination percentage and variation in seed yield and size, and had the least variation in germination. Size of black seeds and germination of brown seeds were not affected by maternal environment. These findings indicate that maternal nutrient and water levels differentially affect seed yield and seed traits of Atriplex aucheri. Appropriate irrigation can not only increase seed yield but also improve the germinability of black seeds.