Studies On Propagation, Medium Cultivation And Flowering Regulation Of Azaleas

Pot Azalea {Rhodedendron hybridum) production of 4 flower colours 'red', 'pink', 'orange ' and 'white edging pink' were studied in respects of propagation of leafy cuttings, potting medium and nutrient management, as well as flowering regulation aimed in new year season.In the azalea propagation of leafy cuttings, rooting test was conducted in brick bed that was covered with plastic film in spring, otherwise, the rooting was conducted under mist in summer. Different rooting medium, concentration of INA+NAA and type of cuttings were tested, data showed that perlite + peatmoss had higher root length (14mm) than perlite and perlite + vermiculite; cuttings treated with 1000 and 1500 mg/L of IB A +NAA rooted best (rooting rate 100%). Terminal cuttings had highest root number(48.7). In under mist condition, the best concentration of IBA +NAA is also the lOOOmg/L and 1500 mg/L level. In another test, IBA +NAA in talc rooted better than IBA +NAA in solution. 12000 and 16000 mg/kg had 100% rooting rate, 16000 mg/kg had the highest root number (79.6) and root length (1.79cm).Pot azaleas were grown in 7 kinds of mixed medium, plants were measured after 1 year growth, the data showed that azalea grew best in coconut fiber: peat moss: perlite 2:l:lplus 0.5% of wet agent gaming the highest height(30.7cm), diameter(33.2cm) and leaf area(6.35cm2); azaleas also grew well in the same media without wet agent; azaleas grew normally in 3 other medium of coconut fiber: peat moss: perlite 1:1:1; peat moss: perlite 2:1; peat moss: perlite 1:1; azaleas grew unnormally in2 medium consisted of coconut fiber and perlite.Nutrient solution of Siders and Young was tested on uniform azalea potted in medium of coconut fiber : peatmoss : perlite 2:1:1, data showed that azaleas grew well in constant applying method, 3 nutrient applying plus 1 water method had highest new shoots(168) and leaf area(7.52cm2). EC level showed an increasing trend and reach to 0.87ms/cm after 20 times constant nutrient applying, pH level showed a decreasing trend and it was below 5.0 after 30 times of constant nutrient applying. 3 or 2 times of nutrient applying plus 1 time water maintained correct pH level of 5.5.In tunnel greenhouse condition, the flowering influence of different disbudding and protecting time were comppared, data showed that disbudding in Jul.25, start protected cultivation in Nov.l had the best flowering effect, the coloured bud reached to 124.5, the flower number 139.7. Effects of three growth retardants--B9, CCC and PP333 on the flower bud initiation and GA3 on the flower forcing were studied. Growth retardants would initiate flower bud by inhibiting plant growth, but also inhibit flowering process. GA3 would stimulate bud to flower effectively, spraying 300 mg/L PP333 solution twice before bud initiation and spraying 1000mg/L GA3 solution 8 times in the later stage of bud development is the best method on azalea flowering forcing. In this treatment, buds appear color or partly open abundantly by Jan. 10, flowers bloom abundantly by 10 Feb., pot plants could be marketed much earlier.