Effects of foliage fertilizing, maximum leaf length in layering shoot and injuring on layering shoot rooting during Salacca zalacca air layering

In order to optimize propagation techniques of Salacca zalacca air layering, taking N, P, K compound fertilizer made in Norway as foliage fertilizer, effects of foliage fertilizing, maximum leaf length in layering shoot and injuring method on layering shoot rooting during S. zalacca air layering were studied. The results show that foliage fertilizing and maximum leaf length in layering shoot both have signifi cant effects on layering shoot rooting in S. zalacca, the optimum mass concentration of foliage fertilizer is 3 000 mg/L, and the optimum length of the longest leaf is 100-120 cm. Scraping stem has a similar effect on layering shoot rooting with deeply injuring stem, and both of them are suitable for S. zalacca air layering.