The response of biomass allocation and hosts phenology of Pedicularis kansuensis to snow cover

In the present study, the response of biomass allocation of Pedicularis kansuensis and the phenology of P. kansuensis and its hosts to the snow cover changes with the level ±21.54 % for annual average snowfall depth in winter of alpine grassland in Bayinbuluke of Xinjiang were study to analyze their competition and reproductive strategies. Our results showed that the snow cover made the growing season of P. kansuensis and hosts having no consistent change law compared to CK. The flowering phenology of P. kansuensis and most typical hosts advanced under snow cover, which made their autumn phenology postponed. The beginning time of phenology period of P. kansuensis keep ahead of hosts from productive phase to seed dispersal. The reproductive allocation and root to shoot ratio of P. kansuensis significantly decreased(P<0.05). The plant height, canopy, column height and the size of lateral root of P. kansuensis under snow cover addition had significant difference with CK(P<0.05), however, except with lateral root, plants had no significant difference after snow cover removed. Totally, the same phenology stages of P. kansuensis and its hosts had certain differentiation after snow cover change, while the biomass allocation and individual morphology were more sensitive to snow cover which reduced reproductive investment and enhanced nutrient investment under snow cover change