Study On The Mechanism Of Southern China Fresh-eat Jujube Dropping Flowers And Fruit

Southern China fresh-eat jujube,sweet,small nutlet,highly edible rate,has unique rflavor,good taste and outstanding nutritional value,having great potential in the international and domestic market.Southern China fresh-eat jujube,developing rapidly,has become one of the main varieties of southern red dates.Southern China fresh-eat jujube has lots of flowers,but the vast majority of flowers will fall off after blooming and even if some flowers set fruits,which will become yellow then drop,the percentage of harvested fruit is very low.In this study,the Ziziphus jujube cultivar ’Zhongqiusucui’ was used to be experimental materials,and the flowering process of single flower,the characteristics of falling flower and fruit,the dynamical regulation about flower and dropping in two batches of two types of bearing shoot,the changes of contents of endogenous hormonesin flowers in two batches of two types of bearing shoot in flower dropping period,the comparison of contents of endogenous hormones in fruit in two batches of two types of bearing shoot in physiological fruit dropping period were studied by fixed-point observation,structural anatomy,paraffin section,hormone determination and other methods.And the Canon EOS 70D camera,stereo microscope,biological microscope and other equipment were used in this experiment.This study will provide a theoretical basis for flower and fruit management of the Ziziphus jujube cultivar’Zhongqiusucui’.This paper comes to the following conclusions:(1)The Ziziphus jujube cultivar ’Zhongqiusueui’ flowers open for daytime.Different air temperature and humidity conditions,the time of buds bursting is different,but from the buds bursting to the petals drooping are about 9.33h,petals and stamens instantly separated during the day.5 days after single flower bud bursting ovary began to expand to become young fruit.Physiological deflowering be off after 6-7 days from bud bursting.Non-physiological deflowering drys up after 2-4 days from bud bursting.(2)The ovule of physiological deflowering and physiological fruit drop were atrophic.(3)The average intemodes and total flowers of two batches of two kinds of bearing shoot are different.The first batch lignified bearing shoot and non-lignified bearing shoot internodes on average are 17.6 and 15.4,the total amount of flowers on average are 139.38 and 129.38;The second batch lignified bearing shoot and non-lignified bearing shoot intemodes on average are 16.0 and 11.4,the total amount of flowers on average are 64.33 and 46.90.(4)Having the largest number of buds is different in two batches of bearing shoot of internodes.The first batch lignified bearing shoot usually in the first 5 to 7 internodes inflorescence have the largest number of buds;The second batch hgnified bearing shoot usually in the base of the first 1 to 4 internodes inflorescence have the largest number of buds.(5)Two batches of two kinds of bearing shoot hanging flowers and setting fruit concentrated nodes are different.The first batch bearing shoot flowering nodes are mainly concentrated in 2 to 12 internodes and finit set nodes are mainly concentrated in 5 to 12 internodes;The second batch bearing shoot flowering nodes are mainly concentrated in 1 to 7 internodes and fruit set nodes are mainly concentrated in 1 to 10 internodes.(6)The flowering stage of the first batch bearing shoot and the second batch bearing shoot are about 40d,but the second batch bearing shoot begins its flowering stage later than the first batch bearing shoot about 10 days.The flower dropping rate of Two batches of bearing shoot are a single peak curve.After 10 to 20 days of the beginning of flowering stage the first batch bearing shoot reaches the flower dropping peak;After 20 to 30 days of the beginning of flowering stage the second batch bearing shoot reaches the flower dropping peak.(7)The physiological fruit drop stage of the first batch bearing shoot and the second batch bearing shoot are about 50d,but the second batch bearing shoot begins its flowering stage later than the first batch bearing shoot about 10 days.The physiological fruit drop rate of the first batch bearing shoot and the second batch bearing shoot are bimodal curve,there are two physiological fruit drop peak period.The physiological fruit drop stage of the first batch bearing shoot is mainly concentrated in 10 to 20 days after the beginning of fruit stage;the physiological fruit drop stage of the second batch non-lignified bearing shoot is mainly concentrated in 0 to 20 days after the beginning of fruit stage;the physiological finit drop stage of the second batch hgnified bearing shoot is mainly concentrated in 20 to 30 days after the beginning of fruit stage.(8)The total flower and fruit dropping rate of the first batch non-lignified bearing shoot is 98.24%,1.03%higher than the first batch lignified bearing shoot;the total flower and fruit dropping rate of the second batch non-lignified bearing shoot is 97.99%,4.87%higher than the second batch lignified bearing shoot.(9)There were differences in the jujube flower hormones between the two batches of two bearing shoot.In the first batch lignified and second batch lignified bearing shoot,withering period jujube flower in relatively high concentrations of ABA,GA3,and ABA/(GA3+IAA+ZR)ratio increasing promote ovary to inflate;in the first batch non-lignified bearing shoot,withering period jujube flower in relatively high concentrations of ABA,ZR and ABA/(GA3+IAA+ZR)ratio increasing promote ovary to inflate;in the second batch non-lignified bearing shoot,withering period jujube flower in relatively low concentration of ABA,ZR and ABA/(GA3+IAA+ZR)ratio decreasing promote ovary to inflate.(10)There were differences in the jujube fruit hormones between the two batches of two bearing shoot.In the first batch lignified and second batch lignified bearing shoot,low concentration of GA3,IAA and ABA result in physiological fruit drop;in the first batch non-lignified and second batch non-lignified bearing shoot,high ABA result in physiological fruit drop;GA3 and ZR abnormally elevated lead to physiological fruit drop;in the first batch lignified bearing shoot,first batch non-lignified bearing shoot and second batch non-lignified bearing shoot,high level of ABA/(GA3+IAA+ZR)ratio lead to physiological fruit drop;in the second batch lignified bearing shoot,the abnormal reduction of ABA/(GA3+IAA+ZR)ratio is related to physiological fruit drop.