Breeding of a new grape rootstock cultivar‘Zhenghan No. 1’北大核心CSCD

‘Zhenghan No.1’was newly selected from hybrids of the cross between‘Hean 580’(female parent) and Shan putao (male parent) in 2008，432 hybrid seeds were harvested in autumn. In March 2009，156 hybrid seedlings were obtained by sowing hybrid seeds through sand accumulation treatment. Through selection and elimination，120 hybrid seedlings were preserved until 2011. In 2012，46- 8- 4 showed the characteristics of high cold resistance and salt-alkali resistance，and was designated as a superior cold-resistant rootstock line. In 2013，regional test sites were established in Weishi county in Kaifeng，Changyuan county in Xinxiang，Mengzhou county in Jiaozuo and Yanqing county in Beijing，and main varieties such as Sunshine Rose，Xiahei Seedless and Hutai No.8 were grafted. Regional test showed good grafting compatibility. The cultivar is high resistant to salinity tolerance，wide adaptability and high yield. It has good grafting affinity with common varieties in production.‘Zhenghan No. 1’ has strong growth potential，strong branch growth，few bad branches，good maturity of branches，and can yield 10 250 meters per mu. The relative conductivity and recovery growth of branches were measured after freezing at different temperatures. The semi- lethal temperature of‘Zhenghan No. 1’ was -30.78 ℃ ，‘Beida’was -28.88 ℃ ，‘Zhenghan No. 1’had higher cold resistance than‘Beida’，and the germination rate of‘Zhenghan 1’was also higher than‘Beida’. In spring，18 rootstocks of one-year- old‘Kangzhen No. 3’‘Kangzhen No. 1’‘HuajiaNo.8’‘DogRidge’‘Saltreek’‘Cloire’‘Beida’ ‘SO4‘’3309C‘’1103‘’5BB‘’SandyGrape‘’5C‘’775P‘’110R‘’420A‘’Zhenghan No. 2‘’Zhenghan No. 1’were cut into branches. Cuttings with 3-5 buds were cultured in laboratory. After the cuttings had grown a small number of roots，they were cultured with 1/10 Hoagland nutrient solution until the branches had grown a large number of roots. Treated with different concentrations of Nacl and saturated lime water. The results showed that‘Zhenghan No. 1’could tolerate 0.3% NaCl + 18% saturated lime water under hydroponic conditions，while Beida could only tolerate 0.2% NaCl + 15% saturated lime water. Compared with the commonly used cold-resistant rootstock‘Beida’，there was no obvious effect on the economic characters of the scion varieties such as‘Summer Black seedless’‘Hutai No.8’and‘Sunshine rose’. The survival rate of‘Zhenghan No. 1’grafted with‘Summer Black Seedless’and‘Hutai No. 8’was 90.0% and 86.6%，respectively; the yield of‘Sunshine Rose’grafted with‘Zhenghan No. 1’ could reach 646 kg in the second year and 2 132 kg in the third year. It can be seen that ‘Zhenghan No. 1’ had good affinity with the main varieties ‘Summer Black seedless’‘Hutai No. 8’and‘Sunshine Rose’. It began to germinate in early April，blossom in early May，branch began to aging in early July，leaves began to fall in early November，and the whole year’s growth period was about 216 days in Zhengzhou. ‘Zhenghan No. 1’had no leaf and branch diseases throughout the year，and no chemical control was needed. ‘Zhenghan No. 1’showed good plantability in different producing areas. It could grow normally in the areas such as Changyuan with low temperature in winter and Boai with cloyed ground. © 2019 Journal of Fruit Science