Study On Blossom Pollination And Bear Fruit Characters In Castanea Henryi

It is very important that higher plants flower and seed for the plants itself or for the human. Study Castanea henryi blossom pollination and bear fruit characters, is the basis of further doing research on good quality and high yield cultivation techniques to Castanea henryi. Using’Tiezhen’,’Changmangzi’,’Bailuzi’ and so on, a total of14varieties as experimental materials, Castanea henryi blossom pollination and bear fruit characters which invovled flowering dynamics, inflorescence and pollen germination characteristics, pollination and fructification, and fruit development were elaborated through field observation, pollination investigation, anatomical studies, and physical and chemical analysis methods, the results were as follows:1. Castanea henryi flowering characteristics observations show that: Floresence of female flowers is about11days, and male flowers is about19days, but male and female flowers full-bloom stage only have3～5days. Male infloresences of different varieties have different length, but in one varieties, length of bisexual inflorescence is shorter than length of staminate inflorescences, and the minimum distance between male and female flowers is proportional to the bisexual inflorescence length. Staminate inflorescences have the largest amount of powder in4days after flowering, and its pistillate flowers have he best pollination period in5-7days after flowering.2. Castanea henryi pollen in vitro culture studies show that:14varieties pollen germination rate were lower than40%; N, P, K, Ca, Mg, B7kinds of nutrient elements have different effect on’Tiezhen’, and its pollen germination rate increased from13.48%to68.42%with the optimal proportion of0.05g·L-1K2SO4+0.05g·L-1CaCl2+0.05g·L-1H3BO3;2,4-d, GA3, IBA, NAA4kinds of plant growth regulator under certain concentration can promote pollen and pollen germination rate increased from29.59%to73.79%with the optimal proportion of2.0mg·L-12,4-D+ 50.0mg·L-1GA3+4.0mg·L-1IBA.3. Castanea henryi pollination characteristics studies show that pollens on the top of acicular stigma germinated after pollination3days, and its pollen tube entered into the ovary after pollination25days, while the pollens outer the bifurcation style germinated later relatively, and pollen tubes intertwined and grew disorderly, did not enter inside.One female flower of Castanea henryi has six sepals around bifurcation style, and12staminodes hidden under sepals. In generally, one involucrum just has one ovary, but two to three rarely. One ovary contains8～11loculi and each loculus has two2anatropous, bitegminous and crassinucellate ovule.the embryo sac development is Polygonum type, in addition, the megaspore mother cell was not observed in a handful of ovule, and after many ovule form the mature embryo sac, which seven cells with eight nuclear disintegrated. Castanea henryi male and female flowers matured in different period, which mainly performed in the lagging development of embryo sac. when female flowers have flowered about40days, the mature embryo sac is formed. Different pollination of Castanea henryi have different influence on its fruit-bearing. Self-pollination fruits have experienced three times of fruit drop peaks, while natural and cross pollination fruit have experienced two times of fruit drop peaks. When fruits were ripe, the self-pollination seed setting rates(12.88%) is lower than natural pollination seed setting rates(42.54%), both of which is also lower than cross pollination seed setting rates(59.64%). Involucrum and ovary transverse diameter growth curve in three ways of pollination is "S" type, and when fruits were ripe, self-pollination involucrum and ovary transverse diameter is shorter than natural pollination involucrum and ovary transverse diameter, both of which is also lower than cross pollination involucrum and ovary transverse diameter. Involucrum quality growth curve in three kinds of pollination is "double S" type, while ovary quality in three kinds of pollination grows slowly in early days, then grows fast, and when fruits were ripe, self-pollination involucrum and ovary (nuts) quality natural pollination is lighter than natural pollination involucrum and ovary(nuts) quality, both of which is also lower than cross pollination involucrum and ovary(nuts) quality. Nuts (ovary immature embryo) development in three kinds of pollination, focused after July26.4.’Changmangz’ nut weight, kernel weight, and total starch weight in the kernel increased by6.14g (92.4%),4.97g (99.43%),3.82(99.93%). Ca and Cu contents in the leaves of bearing branch showed a significant decrease tendency, while P and Zn showed an increase tendency; Cu contents in the leaves of foliage branch had a decrease tendency, while P and Zn had an increase tendency; In the prickly burs, Ca, Fe, and Cu contents had a decrease tendency, while Zn increased at the early stage and then decreased, and other mineral elements did not change significantly; In the pericarp&seed coat, N, P, K, Mg and Cu contents had a slight change at the early stage an then decreased significantly, while Ca and Zn increased at the early stage and then decreased; In the kernel, N, P, K, Ca, Mg, Mn, Fe, Zn, and Cu contents had a decrease tendency, while their gross had an increase tendency. The total starch in the kernel was significantly and negatively correlated with the contents of Cu in the leaves of bearing branch, the leaves of foliage branch, and the prickly burs, and the contents of K, Mn in the pericarp&seed coat, while significantly and positively correlated with the contents of N, P, K, Mg, Mn, Fe, Zn, and Cu in the kernel.