Studies On The Using Valuble Of Aged Hybrid Rice Seeds

Using the aged seeds of 12 hybrid rice combinations, whose germinationrate are more than 80% (the seeds crossed a normal year) as the materials, which are Jinyou402,Ⅰyou 402, luliangyou996, Liangyoupeijiu,Ⅱyou441,Ⅱyou838, Shanyou63, Jinyou207,Tyou259, Xinxiangyou80, Weiyou46, Shanyou 46, the new seeds of the same combinationserved(producted on the first year) as the control. Through comparative study on the vitality,field production performance of the new and aged seeds of the different hybrid rice, theresults are as the follows:1. The hybrid rice seeds which germination rate is more than 80% and can germinatenormally in light-temperature germinate bin at the seedling stage, the dry seedling weight perplant have no significant difference between the new and aged seeds; Seeds vitality index ofthe aged seeds are below the new seeds; Soak seeds conductivity of the aged seeds werehigher than the new seeds of the same combination. It showed that the seed vigor of agedseed has decreased.2. Soaking time of the hybrid rice seed affect the germination rate. After soaking 48hours, the germination rate of Jinyou402,Ⅰyou402 seeds have no significant difference. Thegermination rate of aged Luliangyou 996 seed decreased to below 80%. The germination rateof the middle and late hybrid rice dropped to below 80% except Liangyoupeijiu, in whichthe germination rate of aged Shanyou46 seed is only 61%. Except the aged seeds of Jinyou402 andⅠyou 402, the soaking seeds time of other combinations seeds should be within 24hours.3. After seeds sowing of the normal germination, seeding rates of the new seeds aredecreasing, but Luliangyou 996,Ⅱyou441, Tyou 259, Xinxiangyou 80, Shanyou 63, theseedlings of new and aged seeds are not significant difference. The differnce of seedlingsrate are significant betweenⅡyou 838 seeds and the most significant between Weiyou 46seeds. Under 8℃～9℃conditions, the chlorophyll of most aged seed combines content todrop at three times seedlings.4. The difference of seeding quality between new and aged hybrid rice mainlyreflected in tillering rate, stem width and fresh weight per plant. Tillering rate, stem widthand fresh weight per plant in aged seed is lower than in fresh seed, but the significantdifference of tillering rate between new and aged seeds of Xinxiangyou80, Weiyou46, The tillers line of new and aged seed of Shanyou63 seeds of rice with the rate significantly lowerthan the new seeds; Shanyou 63, Weiyou 46, Xinxiangyou 80 seeds significantly lower thanthe new seeds; new seed's stem width ofⅡyou441, Tyou259, Shanyou 63 significantlygreater than aged seeds;The per plant seedling fresh weight of Weiyou 46, Shanyou 63,Ⅱyou441's seeds was significant than aged seeds.5. After transplanting, the growth period of aged seed is shorter one or two days thanthat of new seed. Most of the growth period of aged seeds decrease one day than the newseeds. Shorten the growth period mainly was manifested in the seeding period stage, maturestage shortened less. The yield factors of new and aged hybrid rice seeds were follow thegeneral rice rule, the spike, grains restraint, and coordination are restricted each other. Theultimate yield have no significant difference between the new and aged seeds.In summary, in the seeding rate and quality seedlings, aged hybrid rice seed whichgermination rate are more than 80% were poorer than new seed. when the Soaking seedstage and seedling stage should be strengthened. Aged hybrid rice seeds have vigoradvantage in the field production. Thus, the aged hybrid rice seeds which have germinationrate are more than 80% can be used in production.