Researches On Collecting Time And Storage And Germination Characteristics For Jacaranda Acutifolia Seeds

Jacaranda acutifolia was Deciduous tree of Bignoniaceae Jacaranda. The researches about them almost focused on as pulping,ornamental plants and landscaping in the world. There were few researches on propagation. Jacaranda acutifolia seeds were used as experimental material in the research. The experiment applied to outdoor observation and laboratory analysis. According to effects on germination of collecting time, storage, soaking temperature,germinative temperature and adjustment material. The studies tried to find the best collecting time ,the appropriate storage ways and time and the optimum soaking temperature,germinative temperature and the best adjustment material. The results showed that:(1)Jacaranda acutifolia fruit was capsule ,wide oval and flat. The length was 4～6 cm and the width was 3～5 cm. The fruit color was heavy brown. There were 45～95 seeds in every fruit. The seed was flat .The seed color was brown. The length was 5.7～6.4mm,the width was 4.8～5.5mm. The 1000-grain weight was 8.823g.(2)Jacaranda acutifolia seeds absorbed fast and germinated quickly. Seeds absorbed rapidly when soaking 0～9 hours. Seeds absorbed slowly in 9 to 18 hours and rapily in 18 to 21 hours,this was the second imbibition peak,then seeds absorbed slowly in 21 to 24 hours. So Jacaranda acutifolia seeds should be soaked 24 hours and then sowed.(3)The 1000-grain weight was different when collected in different time.there was small difference when collected in November and next June. But there was only 7.201g when collected in August,and there was big difference between the former one. The germination was the best when collected in November. The germination rate, the power of sprouts,the index of sprouts and the seed vigor index were 32.67%,29.00%,3.02,80.33. They were 8.81,13.5,2.20,6.03 times more than collected in August. So the fruits should be collected in November or December every year and stored adaptablely to keep seed quality and enhance germination rate.(4)The germination rate was the lowest by no storage. As time going ,the germination rate rose and then dropped, there was shell or not ,the germination result was the best when stored 60 days. The germination rates were 81.33% and 76.67%.The seed vigor indexes were 730.20 and 697.64.It indicated Jacaranda acutifolia seeds needed afterripening and then enhanced the germination rate. As time going ,the rate of germination , the power of sprouts ,the index of sprouts and the vigor index dropped when stored with shell. The result was better storage under low temperature than storage under room temperature. The best storage scheme was storing seeds in 5℃environment and then stored continuely without shell after 2 months.(5)The adaptable germination temperature range was 26 to 28℃. The appropriate germinate temperature and soaking temperature can largely enhance germination and seed vigor. The germination rate, the power of sprouts ,the index of sprouts and the seed vigor index were 75.29%,35.40%,31.77,770.22.So the new seeds should be soaked 24 hours in 25℃warm water before sowing or soaked in 45℃warm water when stored more than 2 months.(6)The effects on Jacaranda acutifolia seeds were different when treated with different adjustment material and different concentration. There was high germination dealing with 15% PEG, the germination rate, the power of sprouts ,the index of sprouts and the seed vigor index were the best. The treatments dealed with urea can improve germination . The germination rate, the index of sprouts and the seed vigor index were 26.67%,7.49 and 259.83 when dealed with urea which concentration was 0.125%.The result dealed with urea was better than the control. The germination rate was high dealing with NH₄Cl soaking half an hour in concentration 50mg/L,150mg/L when stored nine months. The germination rates were 82.67% and 81.33%. The germination rate, the power of sprouts ,the index of sprouts and the seed vigor index were best when soaking inNH₄Cl half an hour which concentration was 150mg/L.