美国薄壳山核桃设施育苗技术

Techniques for Industrial Seedling Cultivation of Carya illinoensis

于10月份采收美国薄壳山核桃种子进行砂藏,并于次年1月中旬进行25℃以上增温催芽,挑选已破口或生出胚根的种子,分期分批进行营养钵容器限根培养,要求营养钵大部分埋入苗床,并在苗床上加盖拱棚,覆盖遮光率70%的遮阳网;8月80%以上的砧木苗达到嫁接标准,控制大棚温度35℃左右,湿度70%,进行芽块嫁接,嫁接时在芽块下方割2 cm长的小口,使伤流液流出,可使嫁接成活率达到85%以上,当年达不到嫁接标准或嫁接不成功的则继续培养,次年春季进行劈接或夏季芽接;春季芽体萌动后,保证苗木生理活动充足的水分,以后每两周浇一次透水,气温升高后,每周浇一次透水;幼苗正常展叶、茎干转绿时开始揭膜,并开始施肥,每月施一次复合肥（14N-6P-11.6K）,12 g/营养钵,9月开始停施N肥,每隔15 d喷施一次0.2%~0.5%的磷酸二氢钾,施用复合肥的同时每两周叶面喷施一次3.6 g/L的ZnSO4.H2O,可将美国薄壳山核桃出圃时间由3~4 a缩短到2 a。

Harvesting of pecan was conducted on October and seeds were stored in sand.By the mid-days of January of the next year,pregermination of seeds was carried out by maintaining storage temperature at 25℃,then cracked seeds or with embryo roots were planted in containers buried most part in seed bed,which should be covered by film with 70% of shade.On August,about 80% seedlings could be grafted by bud-block grafting at 35℃ and 70% of humidity.A key technique was to cut bud block 2 cm underneath for outflow of bleaching sap,leading survival rate of 85%.Seedlings not met the demand for grafting or not survived were cleft graft in next spring or bud grafted in summer.In the spring watering grafted seedlings was implemented one time every two weeks,and over time,one time per week.When grafted plant produced leaves and stem turned green,application of 14N-6P-11.6K by 12g/container every month,N fertilizer stopped on September,spraying 0.2%-0.5% of Potassium dihydrogen phosphate every 15days.Application of 14N-6P-11.6K with spraying 3.6g/L of ZnSO4.H2O could shorten grafted seedling time from 3-4 years to 2 years.