A Seeding Method To Increase Efficiency In The Production Of Glyphosate-resistant Cotton Hybrid

Cotton is an important cash crop in China.Cotton has obvious heterosis.And obvious heterosis can inprovre yield.Spraying glyphosate can cause cotton sterility.This is a new way to kill cotton males.People use this method to produce hybrid seeds.In this experiment,We use glyphosate-resistant transgenic cotton S06-1 to produce hybrid seed in shandong province.The main research results are as follows: 1.Determination of appropriate glyphosate concentrationSpraying glyphosate which has different concentrations to glyphosate-resistant cotton.The results showed,The transgenic glyphosate resistant cotton which spraying the concentration of glyphosate that 3.6 g/L had long period and high boll setting percentage;The transgenic glyphosate resistant cotton which spraying 7.2 g/L of glyphosate had long period,but the boll setting percentage is low;The transgenic glyphosate resistant cotton which spraying the concentration of glyphosate that 1.8 g/L had high boll setting percentage.but a number of pollen was fertile.It can affectthe purity of hybrids.Therefore,It is suggestion that use 3.6g/L of glyphosate to Produce hybrid seeds.2.Planting density of cotton suitable for producing hybrid seeds in the fieldIn order to insure the high hybrid yield.we increased the The planting density of cotton.The results showed that when planting density was 52500 / ha,It has the hight boll number per plant?boll number per acre and yield.And the purity of hybrid reached 92.5%.3.Use a specific concentration of glyphosate to distinguish between hybrids and self-crossbreedsSpraying the 1.44g/L of glyphosate to smear the Leaf blade of hybrid and self-hybrid.After 7 days,the results showed that the glyphosate-resistant cotton hybrid had no effect,and the leaves of non-glyphosate-resistant cotton SF06 grew yellow color in veins,but no non-glyphosate-resistant cotton SF06 became dry and exfoliated.After 21 days,the new leaves that in the top of the glyphosate-resistant cotton grew normally,But,the non-glyphosate-resistant cotton is new leaves which in the top was died and could not grow normally.Applying 1.44g/L glyphosate to determine the chlorophyll content of leaves.The glyphosate reduced the chlorophyll content in the leaves of SF06,but it had not effect on the chlorophyll content of glyphosate-resistant cotton S06-1.After 7 days,the content of shikimic acid in cotton leaves was determined.The results showed that the content of shikimic acid was accumulated in the leaves of non-glyphosate-resistant cotton,and the content of shikimic acid which smeared the glyphosate was similar to the leave with water in the glyphosate-resistant cotton leaves.After smeared the 1.44g/L of glyphosate,the accumulation of kimkimic acid in the leaves of non-glyphosate-resistant cotton was about three times of that in glyphosate-resistant cotton.Thus,cotyledons of hybrid and self-crossbred cotton can be differentiated between hybrid and self-crossbred by applying 1.44g/L of glyphosate.4.The production of hybrid seed with glyphosate-resistant cotton s06-1 as male parentUsed glyphosate resistant cotton shannon SF06 as female parent,in the cotton budding period,spraying 100 mg/kg concentration of gibberellin,it can promote stigma extension after flowering.then,used the glyphosate-resistant cotton S06-1 as male parent,artificial supplementary pollination,using 1.44 g/L of glyphosate identified the hybrid seed which was harvest.the results show that the cotton hybrid purity was 72.5%.