Spatial distribution of SPAD value and determination of suitable leaf for N diagnosis in cucumber
1.Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, Jiangsu University, Zhenjiang, Jiangsu 212013, China| 2.Suzhou Institute of Industrial Technology, Suzhou, Jiangsu 215104, China
Abstract： To determine the best leaf position for nitrogen diagnosis in cucumber with SPAD meter， greenhouse experiments were carried out to study spatial distribution of SPAD value at different position of the 3rd fully expanded cucumber leaf for different nitrogen levels, and the correlation between SPAD va lue and nitrogen concentration of chlorophyll was also analyzed. The results show that there is remarkable difference for SPAD value at different positions of the 3rd fully expanded leaf in the flowering and fruiting stage. Comparing the coefficients of SPAD value variation, it is found that the variation coefficient of leaf edge is significantly higher than that of the main vein edge, while the variation coefficient of triangular area of leaf tip is significantly higher than those of other leaf areas. There is a significant correlation between SPAD value and leaf nitrogen content. Preliminary study shows that triangular area of leaf tip from the 20% leaf tip to leaf edge is the best position for nitrogen diagnosis.
胡静, 毛罕平, 左志宇, 李青林. 黄瓜叶片上SPAD值的空间分布及氮素诊断的位点选择[J]. 江苏大学学报（自然科学版）, 2015, 36(4): 411-417.
HU Jing, MAO Han-Ping, ZUO Zhi-Yu, LI Qing-Lin. Spatial distribution of SPAD value and determination of suitable leaf for N diagnosis in cucumber[J]. Journal of Jiangsu University(Natural Science Eidtion)
, 2015, 36(4): 411-417.
2015, Vol. 36 
