Optimization Of Tillering Onion Tissue Culture Seedling Medium And Test Tube Bulb Induction Conditions

In this study,the start-up of tillering onion tissue culture seedlings was carried out,the rooting medium and tube bulb induction conditions were optimized,and the related physiology was discussed,the results are as follows:1.In order to ensure the continuous supply of tissue culture test materials and speed up the overall test process,a test of breaking the dormancy of tillering onions was carried out with different concentrations of GA₃ and variable temperature as test factors.The test results showed that after the bulbs of tillering onion were soaked in200 mg/L GA₃ for 24 hours,the dormancy-breaking effect was the best.The changes in the transverse and longitudinal sections of the bulb and the state of the young buds are the most significant.The soluble sugar content,VC content,POD activity and CAT activity tend to increase first and then decrease with the increase of days.2.On the basis of a large number of preliminary experiments in the early stage,the start-up of tillering onion tissue culture seedlings and the optimization of the rooting medium were carried out.The start-up medium was set with different hormone ratios as the test factors.MS+0.4 mg/L 6-BA+0.1 mg/L NAA,MS+0.4 mg/L 6-BA+0.1 mg/L IAA,MS+0.1 mg/L 6-BA+0.025 mg/L NAA+0.05 mg/L GA₃ 4 treatments,the rooting medium is set with different hormone ratios as test factors,a total of 1/2 MS+0.05 mg/L NAA+1.5 mg/L IBA,1/2 MS+0.01 mg/L NAA+1.5 mg/L IBA+0.1 mg/L PP₃₃₃,1/2MS+0.1 mg/L NAA 3 treatments,using a randomized block trial design.The test results show that MS+0.4 mg/L 6-BA+0.1 mg/L NAA is the best starting medium.The combination of 6-BA and NAA not only induces a high survival rate,but is also beneficial to the growth and development of tillering onion tissue culture seedlings.Under the stimulation of different hormones,the sensitivity of POD activity is greater than that of SOD activity,and in the effect of POD activity,0.4 mg/L 2IP>0.1 mg/L NAA>0.1 mg/L IAA.1/2 MS+0.01 mg/L NAA+1.5 mg/L IBA+0.1 mg/L PP₃₃₃ is the best rooting medium.The combination of NAA,IBA and PP₃₃₃ has significant survival rate and rooting rate in the induction of rooting of tissue cultured seedlings.It is higher than other treatments,and is conducive to the growth of tissue culture seedlings and the development of roots.Under the stimulation of different hormones,adding a certain concentration ratio of NAA,IBA and PP₃₃₃ to the medium is beneficial to increase the soluble protein content of tillering onion tissue culture seedlings.3.In order to induce tillering onion bulbs,the PB test was carried out with 8 test factors,the comprehensive evaluation index was used as the response value,and the sucrose concentration,paclobutrazol,NAA and photoperiod were selected as significant factors.Then,a 3-factor 4-level orthogonal experiment was designed with sucrose concentration,paclobutrazol and NAA as the experimental factors.After 50days,the agronomic traits and physiological and biochemical indexes of the test-tube bulbs of the tillering onion were measured.The test results showed that when the concentration of sucrose was 90 g/L,the POD activity and SOD activity of the tuber bulbs of the tillering onion were the highest;while when the concentration of paclobutrazol was 0.5 mg/L,the VC content,soluble sugar content,soluble protein content and the POD activity were the highest The highest;and when the NAA concentration is 1.0 mg/L,the VC content and soluble sugar content of tillering onion bulbs reach the maximum.Through intuitive analysis,variance analysis and comprehensive balance analysis of the test indicators,the optimal combination of tillering onion bulb induction is finally obtained as A3B1C3,that is,the concentration of sucrose is 90 g/L,the concentration of paclobutrazol is 0.5 mg/L,and the concentration of NAA is 1.0 mg./L.