Effect of Ethephon and Diquat Dibromide Treatment for Rye Seed Production on Paddy Field

Desiccant was treated to find a way to shorten clum length and protect lodging of rye with Ethephon and a way to advance the harvest time without affecting germination. The results of the desiccant process are as follows for the change of harvest time and seed quality. As for Ethephon treatment, the earing date was delayed two days at the concentration of 250 ppm for the booting stage that when there is no treatment, 5 days later at the concentration of 1,000 or more ppm but no difference for the flowering and maturity stage. The culm length getting shorter as the concentration of Ethephon is higher and the decreasing rate of culm length damaged is 40.1% for 1,500 ppm of booting stage, which is the most effective processing, and the base part culm length damage rate is bigger than the superior upper part culm length decrement rate. Ther was no difference according to the treatment at the number of spike, culm and litter weight but one thousand grain weight was slightly higher in the treatment. There was no any difference in the rate ratio of germination. Yield tended to increase regardless of processing concentration. It reached up to 8% at maximum. The treatment with Ethephon turned out to be the most effective at 1,000 ppm during heading date-time. The number of days it takes from the desiccant treatment to the moisture content for harvesting time is respectively 20 days for seeds of 30 day-treatment, 10 days for seeds of 35 to 45 days-treatment and 5 days for seeds of 50 day-treatment.. As for the harvest time after treatment of desiccant, the treatment at 30th days after the earing is 14 days earlier than the culture by conventional methods, 9 days earlier for the treatment at 35th to 40th day, 4 days earlier for the treatment at 45th to 50th day. When treatment of desiccant is implemented, the one thousand grain weight is heavier as the number of days of treatment gets later. The ratio of germination gets higher as the number of days of treatment after heading gets later but there is no statistically significant difference treated 40 days after the heading. As for the yield of seeds are 30% compared to the culture by conventional methods for the treatment of 30 days after the heading, 48% compared to the culture by conventional methods for the treatment of 35 days after the heading, and 74% compared to the culture by conventional methods for the treatment of 40 days after the heading. Seed quality decreased a bit but it had still eligible as seed. The processing timing of desiccant for the earliest harvest was 40 days after heading date-time during which germination was not affected.