Effect of Nitrogen Fertilization on the Yield and Apparent Soil Nitrogen Balance of Hemp (Cannabis sativa L.)

PurposeTo understand precision nitrogen application in fiber industrial hemp (Cannabis sativa L.) production.

MethodTaking ‘Yun ma No.5’ as experimental material, we set up four levels of nitrogen fertilizer (0, 50, 100 and 150 kg/hm²), and two levels proportions of base fertilizer and topdressing (2/3 base fertilizer and 1/3 topdressing, 1/2 base fertilizer and 1/2 topdressing). The impact of nitrogen application on the agronomic traits, nitrogen accumulation, apparent soil nitrogen balance of hemp was analyzed.

ResultsLow rate of nitrogen fertilizer (50 kg/hm²) could obviously improve the agronomic traits of hemp, however, except plant height, with the increase of nitrogen fertilizer rate, the impact was not obvious. Low rates of nitrogen fertilizer (50 kg/hm²) and high topdressing nitrogen (1/2 base fertilizer and 1/2 topdressing) could help the apparent soil nitrogen balance of hemp. But, the nitrogen accumulation of hemp was superior, when the rates of nitrogen fertilizer and topdressing were 150 kg/hm², 1/2 base fertilizer and 1/2 topdressing, which meant luxury consumption of nitrogen fertilizer existed in hemp.

ConclusionIn this experiment, 50 kg/hm² nitrogen fertilizer, and the ratio of topdressing was 1/2 base fertilizer and 1/2 topdressing was the best nitrogen fertilizer application practice by considering hemp fiber yield and nitrogen balance.