Effects of sand burial depth on Xanthium spinosum seed germination and seedling growth

Abstract

AbstractIn desert habitats, sand burial is an important factor affecting germination of plant seeds and seedling growth.Xanthium spinosumhas strong adaptability in arid desert areas, and is a common malignant invasive plant in Xinjiang, China. The effects of different sand burial depths on seed germination, seedling emergence, growth and biomass allocation were studied to provide a scientific basis for further control ofX. spinosum. Six sand burial depths (1, 2, 3, 5, 7 and 9 cm) were established to explore the response ofX. spinosumseed germination and seedling growth to sand burial. The first emergence time, peak emergence time, emergence rate, seedling growth height, biomass and biomass distribution ofX. spinosumseeds was significantly different at sand burial depths (P< 0.05). TheX. spinosumseeds had the highest emergence rate (71.5%) at 1 cm sand burial and the maximum seedling height (7.1 cm). As sand burial depth increased, the emergence rate and seedling height gradually decreased. Emergence rate (12.25%) and seedling height (2.9 cm) were lowest at 9 cm sand burial. The root length at 9 cm depth (13.6 cm) was significantly higher than that at other sand depths (P< 0.05). The sand burial depth affected the biomass accumulation and distribution ofX. spinosum. As sand burial depth increased, the root biomass and rhizome ratio increased, and the most deeply buried seedlings allocated more biomass for root growth. The optimal sand burial depth for seed germination and seedling growth ofX. spinosumwas 1–3 cm, and high burial depth (5–9 cm) was not conducive to the germination and growth ofX. spinosumseedlings. For prevention and control ofX. spinosum, we suggest deeply ploughing crops before sowing to ensureX. spinosumseeds are ploughed into a deep soil layer.