不同施氮水平下甘蔗内源激素、产量和糖分的变化特征

桂糖42号是我国甘蔗推广面积最大的自育品种,探讨该品种的氮肥需求特性,可以为指导该品种在蔗区科学管理提供理论依据。以桂糖42号为供试材料,在分蘖前施用不同水平的氮肥（CK：尿素0 kg/hm ²;低水平：尿素150、300 kg/hm ²;中水平：尿素450 kg/hm ²;高水平：尿素600、750 kg/hm ²）,研究不同氮肥水平甘蔗内源激素含量（GA、CTK、BR和ABA）、产量和糖分的变化特征。结果表明,不同施肥水平下甘蔗产量顺序为150 kg/hm ²>300 kg/hm ²> 0 kg/hm ²>450 kg/hm ²>600 kg/hm ²>750 kg/hm ²,其中150 kg/hm ²和300 kg/hm ²分别比对照提高了5.40%和2.54%（P<0.01）,超过300 kg/hm ²施肥量后甘蔗产量呈下降趋势;不同施肥量下的每公顷含糖量从大到小顺序与产量顺序相同,但施氮肥多少不同不会对糖分产生影响;经济效益顺序为150 kg/hm ²>0 kg/hm ²>300 kg/hm ²>450 kg/hm ²> 600 kg/hm ²>750 kg/hm ²;不同施氮肥水平下GA含量和BR含量的表现一致,在150 kg/hm ²施肥条件下达到最高值,随后随施氮肥量的增加而呈下降趋势;ABA则呈相反趋势,即含量随着施肥量的增加而增加;而CTK则呈先升高后下降再升高的趋势。

The Change Characteristics of Endogenous Hormone and Quality Content of Sugarcane under Different Nitrogen Fertilization

The sugarcane variety GT42 is a home-bred variety which is the most widely planted in China. It’s necessary to explore the nitrogen demand of the variety to provide references for the scientific management of the variety in the planting areas. Different nitrogenous levels (CK: 0 kg/hm ², low level: carbamide 150 kg/hm ², 300 kg/hm ², middle level: carbamide 450 kg/hm ², high level: carbamide: 600 kg/hm ², 750 kg/hm ²) were applied to the variety before the tiller stage, and the content of endogenous hormone (GA, CTK, BR and ABA), final yield and sugar content were measured under different nitrogen fertilization level in the tillering stage. The yield under different levels nitrogenous fertilizer from more to less was 150 kg/hm ², 300 kg/hm ², 0 kg/hm ², 450 kg/hm ², 600 kg/hm ², 750 kg/hm ², and the yield at 150 kg/hm ² and 300 kg/hm ² fertilizer level was 5.40% and 2.54% more than the CK, respectively (P<0.01). And the highest yield was in the 150 kg/hm ² of nitrogen fertilization treatment. The sugar content per hectare was in the same order as the yield, but the nitrogen fertilization levels had no effect on sucrose content. The economic benefit in the order from more to less 150 kg/hm ², 0 kg/hm ², 300 kg/hm ², 450 kg/hm ², 600 kg/hm ², 750 kg/hm ². The variation tendency of the content of GA and BR were the same that reached the maximum at 150 kg/hm ² of nitrogen fertilization level and then decreased with the increase of nitrogen fertilization level. The content of ABA was the opposite, increasing with the increase of nitrogen fertilization level. The content of CTK increased first, decreased then and increased finally.