Study on the cross compatibility among 9 apricot cultivars in Xinjiang

【Objective】To understand the cross compatibility between apricot cultivars in Xinjiang,andprovide a theoretical basis for selection of pollinizer.【Methods】The pollen quantity,pollen viability of 9apricot varieties in Xinjiang were examined and the fruit-setting rates and the growth status of pollentubes were evaluated for 72 cross combinations,as experimental material,to determine the cross compati-bility.【Results】The average pollen number of 9 apricot cultivars per anther was 1 474.4 and there was sig-nificant difference in the pollen number of different cultivars. The average pollen viability of 9 apricot cul-tivars was 44.0%,in which‘Kumanti'got the highest pollen germination 80.0% and‘Shushanggan'gotthe lowest,only 17.5%. The average fruit-setting rate of the 9 apricot cultivars that were pollinated withdifferent pollens from various pollinizers was 25.9%,which was 2.7 times higher than the natural pollina-tion on average;the highest fruiting rate 64.2% was found in‘Akeayi',which was pollinated with thepollens from‘Luntaibaixing'. The fluorescence microscopic observation results show that the pollen ofmost apricot cultivars had started to germinate and elongate on stigma after 24 hours of pollination,and the pollen tubes of all cultivars reached to style base after 96 hours,but there were significant differencesin the germination rate and pollen tube growing speed of various hybrid combinations;the most pollentubes of nine hybrid combinations like the female parent‘Jianali'pollinated with the male parent‘Kuerl-etuoyong'stopped growth after reached the middle and lower part of style,and only a few can reached theovary and completed the normal fertilizations.【Conclusion】There were great differences in the pollen num-ber and pollen viability of the different varieties. the pollinate combinations that fruiting rate was less than6% in 72 combinations showed the hybrid incompatibility,of which the pollen tube did not reach thestyle base or its growing speed was too slow. And the pollination combinations that fruit-setting rate washigh showed strong compatibility,of which the pollen tube grew fast and mostly reached the style base,the successfully-reached ratio was high;the combinations were suitable to use in apricot orchards.