Studies On Breeding System Of Three Species In Corydalis DC.

Corydalis is one of the large genus of the North temperate zone. This genusare known to have428kinds in the world, distributed in the north temperateregions, south to North Africa-the edge of the desert areas of India, individualdistribution of the grassland areas of East Africa. Our country has about298species, accounting for70%of the total. We studied and analyzed the floweringdynamics and breeding systems of Corydalis edulis Maxim., Corydalisdecumbens (Thunb.) Pers. and Corydalis incisa (Thunb.) Pers. in naturalpopulations and discussed their adaptability to the environment of early spring, byfield observations and laboratory experiments. The main results are as follows:1. The population of C. edulis come into bloom from March to May andflowering span among populations is72days. The flowering span for a racemewith5-15flowers is14-24days. The life span of one single flower isapproximately5-10days. Spatial positioning of stigma and anthers were spatiallydesperation on the day of anthesis. We conducted that the filaments were shorterthan the styles through pollen vitality and stigma receptivity experiments. There aretwo acceptable pollen contact on the stigma. A self-pollination breeding system canbe reflected by OCI=3, pollinators are required in sometimes; a complex crossbred can be indicated by P/O=857.14, combined with the result of the bagging andaritificial pollination experiment, the breeding system of C. edulis is mixed withself-pollination and outcrossing.2. The population of C. decumbens come into bloom from early March toMay, and reach the flowering stage in late March. Flowering span amongpopulations is about46days; the flowering span for a raceme with6-12flowers is7-11days; the life span of one single flower is approximately3-7days. Spatialpositioning of stigma and anthers were spatially desperation on the day of anthesis.We conducted that the filaments were shorter than the styles through pollen vitality and stigma receptivity experiments. There are four acceptable pollen contacts onthe stigma. A self-pollination breeding system can be reflected by OCI=3,pollinators are required in sometimes; a complex cross bred can be indicated byP/O=935. The breeding system of C. decumbens is facultative outcrossing withpart of self-compatible. The experiments of pollen germination of C.decumbens showed that, the optimal sucrose solution is10%. Flower openingwithin1-2days showed maximum activity, with the germination rate of76.97%. Stigma can reach the highest receptivity within1-2days after theflowering by the method of benzidine-hydrogen peroxide.3. The population of C. incisa come into bloom from early March andflowering span among populations is43days. The flowering span for a racemewith15-30flowers is12-17days. The life span of one single flower isapproximately2-7days. Spatial positioning of stigma and anthers were spatiallydesperation on the day of anthesis. We conducted that the filaments were shorterthan the styles through pollen vitality and stigma receptivity experiments. There aremore than four acceptable pollen contacts on the stigma. A self-pollination breedingsystem can be reflected by OCI=3, pollinators are required in sometimes; acomplex cross bred can be indicated by P/O=526. The breeding system of C.incisa is facultative outcrossing with part of self-compatible. The experimentsof pollen germination showed that, the pollen of C. incise had the highestgermination rate of71.58%in the early flowering stage (petals slightly open)in10%sucrose solution. Stigma have the highest receptivity from petalsslightly opening to1-2days after the flowering by the method ofbenzidine-hydrogen peroxide.