Effect Of Light And Fertilization On Growth,Reproduction And Sex Allocation In Hosta Ventricosa

The biological and non-biological factors(including temperature,light,soil,water,air,etc.)affect the plant growth in nature is changing with time and space,which namely environmental heterogeneity.Environmental heterogeneity results in the decrease of resource availability in different environmental conditions,after long-term natural selection,In order to achieve maximum fitness,plants have evolved a set of complete resource allocation model,allocated the limited resources to growth,reproduction,and other components reasonablely.sex allocation,the core component of life history,is mainly research about the resource allocation between male and female sexual function.The pattern of resource allocation in plants changes with the change of habitat conditions.Therefore,Exploreing how the resource allocation response to the environmental changes in natural is very significant to realize the evolution history of plant.Field potted plant experiment in this paper,in the control of light intensity(strong light,weak light)and fertilizer(fertilizer respectively 10g,5g,0g)conditions,characteristics of growth and sex allocation model in Hosta ventricosa is discussed.Sex allocation,respectively,expressed by two different indexes:biomass index(biomass of stamens,biomass of pistil and ratio of biomass of stamen/biomass of pistil per flower)and quantitative index(pollen,ovule and P:O ratio per flower).Provide theoretical basis for the strategy of response to the change of light and fertility in Hosta ventricosa.The main results were as follows:(1)Light and fertilizer has a significant influence on growth and reproduction in Hosta ventricosa,The flower number in strong light is significantly more than weak light(P<0.01);leaf area in weak light larger than in strong light dramaticlly(P<0.01);Remarkablely,The more fertilizer the greater plant height(P<0.01);The interaction of light and fertilization has obvious effect on the plant height and number of flowering.The nutrients used on the growth of aboveground part is not absorbed from the soil,photosynthesis is.more resources distributed to the vegetative growth to improve the competitiveness of the plant itself in weak light,but under the strong light,more energy is put in to reproduction,to increase the potential productivity.The interaction effect of light and fertility on plants redistribution of resources,in order to achieve the optimal compensation mechanism.(2)Light and fertilization has significant impact on sex allocation in Hosta ventricosa.Measured sex allocation by biomass index:light and fertilization respectively has no significant effect on stamens,and pistil biomassper flower.The greater the intensity of the light,significantly bigger ratio of stamen,pistil biomass per flower(P<0.01).With the increase of fertilizer,stamens/pistil biomass ratio per flower was significantly decreased(P<0.01);Measured by quantitative index:light and fertilizer had no significant effect on ovule respectively per flower,fertilizer has a significant influence on pollen per flower(P<0.050),light has no significant effect on ovule per flower,with the strength of illumination,pollen/ovule ratio per flower has no significant variation(P=0.93),with the increase of fertilizer,pollen/ovule ratio per flower significantly decreased(P<0.05).(3)Inflorescence position has a significant impact on sexual allocation patterns in Hosta ventricosa.from the base(first open flowers)to the top(after open flowers),biomass index(stamen biomass,pistil biomass),and quantitative index(pollen,ovule)per flower were significantly increased,reproduction input at the base is greater than the top.there is no significant difference between ratio of stamen,pistil per flower at the base and the top(P=0.380).The pollen,ovule ratio per flower at the base significantly greater than the top(P<0.01).from the base(open flowers first)to the top(after open flowers),showed partial female sex allocation in Hosta ventricosa.(4)There is no size dependent sex allocation in Hosta ventricosa.Expressed sex allocation by the biomass:the size of plant influence significantly on stamens biomass per flower(P<0.01)and pistil biomass per flower(P<0.05),but no significant influence on ratio of stamens/pistil biomass per flower(P=0.106).size dependent sex allocation does not exist;Expressed by the number:the effect of the size of plant on pollen(P=0.073)and the ratio of Pollen/ovule(P=0.796)is not significant.but significant effect on ovule(P<0.01).size dependent sex allocation does not exist either.