Studies On Induction Of Haploid Cucumbers By Irradiated Pollen Pollination Combined Embryo Rescue

Cucumber(Cucumis sativus L.) is one of the world’s top ten important vegetable crops, and it is planted widely in the world. However, the genetic base of cucumber is narrow, breeding of new variety via conventional breeding techniques is not only waste time and energy, but also has low efficiency. It can accelerate the process of breeding through using haploid. Using irradiated pollen pollination combined with embryo rescue is one of the important method to induce haploid and double haploid (DH), via this techniques we can quickly obtain pure breeding lines, shorten the breeding period and improve breeding efficiency. In this study, in order to research the effects of cucumber genotype and irradiation doses on the induction of haploid reproduction, we select different cucumber genotypes as materials, and pollens irradiated by different doses. The results were as:1. Analysis of irradiated pollen pollination combined with embryo rescue to induce haploid showed that genotypes&gamma ray dose have effective influence on the rate of plants regeneration. The rate of plants regeneration under different irradiation doses (150Gy,250Gy,350Gy) were5211(3.92%)>CC3(0.42%)>Nankang No1(0.32%),5211(1.64%)>Nankang No1(0.15%)>CC3(O.11%), CC3(0.15%)>Nankang No1(0.08%), respectively. The rate of haploid plants regenerated were5211(1.96%)>CC3(0.21%)>Nankang No1(0.19%)and5211(1.64%)>Nankang No1(0.15%)>CC3(0.11%),5211(0%)、Nankang No1(0%)、CC3(0%), respectively. Different gamma ray dose had influence on the rate of regenerative plants. In comparison with the rate of regenerative plants on the same genotype and different gamma ray doses,150Gy was better than350Gy. In comparison with the same gamma ray dose and different genotypes,5211had high rate of regenerative plants(3.92%) and haploid plants regenerated (1.96%). Nankang Nol had low rate of regenerative plants (0.32%) and haploid plants regenerated (0.19%). In comparison with different gamma ray dose and different genotypes, the rate of low dose (150Gy) was different among three cultivars, the rate of high dose (350Gy) is low,5211was0, CC3was 0.08%and Nankang No.1were0.15%. The rate of CC3and5211fluctuated greatly, so it was sensitive to the dosage. Nankang No.1was on contrary. Analysis of the model shows that, the irradiated dose has larger effect than the genotype, and the radiation dose is the main factor to affect the regenerative rate.2. The induction of irradiated pollination haploid has better effect in autumn than in the spring.Perhaps the preservative method of the irradiated pollen is inappropriate. But it can affirm that, if the cultivated conditions and radiated operation are suitable, the induction of haploid both in spring and autumn are feasible.