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This paper reported the synergistic effect of KT and IAA, and the effects of age of seedlings, length of hypocotyls, nitrogen contents and NH(+)(4)-N/TN ratio on the induction of female flowers in derooted seedlings of Cucumis sativus L. for the establishment of an efficient system for the induction of female flowers. When cultured on MS basal medium supplemented with KT 3.0 mg/L and IAA 0.01 mg/L, an induction rate of 28% was obtained for the 7-day-old derooted seedlings with 1/2 hypocotyl, 12% and 26% higher than when cultured with KT 3.0 mg/L alone and IAA 0.01 mg/L alone, respectively, while no female flowers was formed on the control medium, which indicates that KT and IAA have an evident synergistic effect on the induction of female flowers. Experiment was done with N concentration of 60-90 mmol/L or with NH(+)(4)-N/TN ratio of 12.5%-50% (total N kept at 80 mmol/L), with lengths of hypocotyls of 0-4/4, and with different ages of seedlings of 5-8-day-old, the highest induction rate of 40%, 48% and 57% for female flowers was achieved on medium of N 80 mmol/L (NH(+)(4)-N/TN 37.5%), from seedlings with 1/4 hypocotyl and from the treatment using 6-day-old seedlings respectively.

Objective: To obtain Maackia amurensis callus and investigate some factors influencing total isoflavonoid production in callus., Method: Different media were used for callus induction from cotyledonary and hypocotyl explants. Total isoflavonoid content was determined by UV spectrophotometer., Result: Medium types and hormone combinations influenced both callus formation and their developmental states. MS medium supplemented with NAA/BA or containing 2,4-D was suitable for callus induction from cotyledonary explants. Among the basal media tested, MS, N6 and B5 were suitable for cotyledonary callus formation and SH for hypocotyl callus formation. The formed callus could synthesize isoflavones. Media containing NAA were suitable for isoflavonoid production in cotyledonary callus and media containing 2,4-D/BA were suitable for hypocotyl callus, but 2,4-D/KT at high concentration inhibited the isoflavonoid accumulation in hypocotyl and coytledonary calli. According to the developmentally morphological characters, the formed callus could be classified into four types. II-type callus with yellow in color and friability in texture showed the highest accumulation of isoflavones., Conclusion: The influences of medium type and hormone combinations on Maackia amurensis callus formation are reflected in both developmentally morphological characters and isoflavonoid accumulation of calli. Yellow, friable callus induced from cotyledonary and hypocotyl explants in MS or N6 medium supplemented with 2,4-D and BA exhibit the optimum growth and isoflavonoid production.