Study On The Prolonged Reproductive Growth Of The Tillers In Puccinellia Tenuiflora And Puccinellia Chinampoensis Populations In Alkalized Meadow In The Songnen Plains

Puccinellia tenuiflora and P. chinampoensis are two salt-tolerant plants of grass family. By big sample, the plasticity of quantitative characters of the reproductive tillers and the growth regulations in P. tenuiflora population and in P. chinampoensis population with different reproductive growth time were analyzed in alkalized meadow in the Songnen Plain of China.The results showed,tiller height, tiller biomass, spike length and spike biomass of the reproductive tillers in P. tenuiflora population increased significantly every five days in early heading stage, heading stage and milking stage as the reproductive growth time was prolonged. Tiller height, tiller biomass, spike length and spike biomass of the reproductive tillers in P. chinampoensis population increased significantly every four days in early heading stage, heading stage and flowering stage as the reproductive growth time was prolonged. There were not regulations in reproductive growth ratio and reproductive allocation. There was large phenotypic plasticity of reproductive growth in the two plants.There was a significantly positive correlation between spike length, biomass and tiller height, and a negative correlation between reproductive growth ratio, reproductive allocation and tiller height in P. tenuiflora population in the four growth stages. There was a significantly positive correlation between spike length and tiller height, between spike biomass and tiller biomass in P. chinampoensis population in the four growth stages.There was large phenotypic plasticity of the reproductive tillers in P. tenuiflora population and P. chinampoensis population. Tiller height, tiller biomass, spike length, spike biomass, reproductive allocation and reproductive growth ratio in P. tenuiflora population increased exponentially as the reproductive growth time was prolonged. Tiller height, tiller biomass and spike biomass in P. chinampoensis population increased exponentially with the time of prolonged reproductive growth, and spike length and reproductive allocation increased linearly, while reproductive growth ratio increased first and then decreased, namely a parabola pattern.There was a significantly positive correlation between spike length and tiller height, between spike biomass and tiller biomass in the reproductive tillers of P. tenuiflora population with different reproductive growth time. Spike length increased exponentially with tiller height in an allometry way, and spike biomass increased linearly with tiller biomass in an isogony way in P. chinampoensis population.