The Relationship Of Fruit Polymorphyism And Population Adaptive Of Six Ephemearl Plants Of Cruciferae In North Of Tianshan Mountains

The northern of Tianshan Mountains is located in the northwest arid area of China, there are rich ephemeral plant resources. The Tianshan Mountains is one center of the distribution of Arabidopsis thaliana and its related species. A.thanalia and its related species:Malcormia africana (L.) R. Br., Lobularia maritima (L.) Desv., Leptaleum filifolium (Willd.) DC, Alyssum linifolium Steph.ex wild, Tetracme quadricornis and other Cruciferous ephemeral plants which grow under the local unique geographical and climate conditions, are widely distributed in that area.Current work on A.thaliana in molecular genetics has accumulated a wealth of research results, but the characteristics of natural distribution habitats and phenotype changing characteristics in changing environment of A.thaliana, M.africana (L.) R. Br., L.maritima (L.) Desv., L. filifolium (Willd.) DC, A.linifolium Steph.ex wild, T.quadricornis are few studied, which greatly limits the understanding of the dynamic evolution and mechanisms of related species. In order to understand the characters of populations distribution and phynotype change of six Cruciferous ephemeral plants under micro-environment, this reaserch studied the relationship between environmental factors and populations distribution characters and phenotypic changing characteristics of many populations which distributed inTarbagatay Mountains, Altai Mountains and Tianshan Mountains characteristics of the six species. The results showed that:Shoot height, Shoot biomass, Root biomass, Single fruit weight, Number of fruits, Total Fruits weight, Fruit length, Fruit dehiscence force, Total Fruits weight/Plant biomass showed significant differences among populations except for branch production of A.thaliana, which indicate that there are strongly plasticity in the nine characters. Fruit length and Fruit dehiscence force have little various in and among populations. Phenotypic characters various little between different mountains, altitudes, latitudes and longitudes.A. thaliana populations were mainly distributing at sandy grounds which content lower HCO3-and pH values, higher SOC and the annual precipitation was between 171mm and 279mm. Frequency distribution within populations of Arabidopsis is very low, at 1.56%-10.69%, and the spatial autocorrelation distance are from 15.4cm to 46.7cm, changed greatly. Ten populations were all highly clumped distribution (P<0.01), which was significantly effects by the fruit dehiscence force, while the fruit dehiscence force increased obviously as environmental intimidation increase. We suggest that the growth and distribution of A. thaliana in North Of Tianshan Mountains are influenced mainly by microenvironments. In drought environment A. thaliana will increases the ratio of reproduct distribution and produces difficult dehiscence fruits which can make seeds dispersed around maternal plants, which can utilize formerly feasible habitats.Branch production, Shoot height, Shoot biomass, Root biomass, Single fruit weight, Number of fruits, Total Fruits weight, Ruit length, Fruit dehiscence force and Total Fruits weight/Plant biomass of M.africana (L.) R. Br., L.maritima (L.) Desv., L. filifolium (Willd.) DC, A.linifolium Steph.ex wild and T.quadricornis showed significant differences among populations. The fruit dehiscence force of Siliques of A.thanalia, M.africana(L.) R.Br., T.quadricornis(Steph.) Bunge, L.filifolium (Willd.) DC were significantly correlated with environmental factors, the general rules for this correlation were that the fruit dehiscence force increased as the reduction of annual precipitation and pH values, HCO3-concentration increased; The fruit dehiscence force of L.maritima (L.) Desv. and A.linifolium Steph.ex wild. were not significant correlated with environmental factors.The fruits of A.thanalia, M.africana(L.) R.Br., T.quadricornis(Steph.) Bunge are long pod mustard fruits, The fruit dehiscence force were positive correlated with the degree of the clumpy of the population distribution patterns, the difficulty cracking fruits can promote short-distance diffusion of seeds which made seeds around the parent plants to ensure the full use of the original offspring suitable habitat. The results show that the fruit dehiscence force played an important role in the the cluster distribution patterns of both the mother and the offspring generation; The fruit of L.maritima (L.) Desv. and A.linifolium Steph.ex wild. is round with short pod, the fruit very easy to crack, the fruit cracking strength with no significant correlation with population distribution pattern, the two species may be larger by producing quality seeds, and higher fruit number, to make up the environmental changes which may brought the high mortality rate, that can ensure the population size.