不同氮肥用量对网纹甜瓜产量和品质的影响

针对设施栽培粗网类型网纹甜瓜施氮不合理的问题,试验设置3个施氮水平：0、100、200 kg/hm²,采用田间调查与室内检测相结合的方法,测定了植株的株高、茎粗、叶片纵横径和坐果节位比较植株长势;测定伸蔓期、结果期、网纹形成期和果实成熟期的顶3叶叶片纵横径、叶色、SPAD值和叶片氮含量;以及甜瓜产量和品质等指标。结果表明：粗网网纹甜瓜的施氮量为100 kg/hm²时品质最佳,产量虽略低于200 kg/hm²的处理,但商品果率最高;顶3叶的叶色、叶片纵横径和SPAD值随着氮肥的施用量增加均表现出相关性,初步摸索了顶3叶对氮素的响应规律,指导田间生产。

Effects of Different Nitrogen Application Rates on Yield and Quality of Netted Melon

To solve the problem of unreasonable nitrogen application of netted melon in protected cultivation, three nitrogen levels were set up: 0, 100, and 200 kg/hm². By combining field investigation with laboratory index detection, plant height, stem diameter, leaf longitudinal and transverse diameter, fruiting node position were measured to compare the plant growth vigor. Leaf longitudinal and transverse diameter, leaf color, SPAD value and leaf nitrogen content of the top 3 leaves were measured at elongation stage, fruiting stage, reticulation stage and fruit ripening stage, and so were the yield and quality indicators. The results showed that the quality of netted melon was the best when the nitrogen application rate was 100 kg/hm ², and the yield was slightly lower than that of 200 kg/hm², but the commodity fruit rate was the highest. The leaf color, leaf longitudinal and transverse diameter and SPAD value of the top 3 leaves showed correlation with the increase of nitrogen fertilizer application rate. The response law of the top 3 leaves to nitrogen was preliminarily explored to guide field production.