Wicharuck Suwimon, Suang Sutasinee, Chaichana Chatchawan, Chromkaew Yupa, Mawan Nipon, Soilueang Phonlawat, Khongdee Nuttapon
Office of Administration Research, Chiang Mai University, Chiang Mai 50200, Thailand.
Energy Technology for Environment Research Center, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200, Thailand.
MethodsX. 2024 Jan 11;12:102566. doi: 10.1016/j.mex.2024.102566. eCollection 2024 Jun.
The utilization of a non-destructive SPAD-502 chlorophyll meter, which enables the measurement of nitrogen status in plant leaves, has gained popularity in agronomic crops. Its application to horticultural crops like coffee remains relatively uncommon. The device provides quick and real-time measurements, helping to provide on-time nitrogen fertilizer to coffee plants before deficiency signs occur. Coffee leaves are characterized by thick and waxy leaves, together with many layers of tree crown. Therefore, the objective of this study was to develop a method for measuring nitrogen levels in coffee plants using the SPAD-502 Chlorophyll meter for an appropriate nitrogen fertilizer application rate in Arabica coffee plants. •Coffee trees were separated into upper, middle and lower levels. Data on SPAD values and total nitrogen were analyzed.•Pearson Correlation Coefficient (R), Coefficient of Determination (R) and linear regression were calculated for different three levels of both SPAD-502 and total nitrogen values.•The results revealed a strong correlation (R = 0.63) between the SPAD readings of coffee leaves obtained from the upper canopy and their nitrogen content. These findings can provide a good concept of which coffee crown level will be a better part for measuring N content using a SPAD-502 Chlorophyll meter.
一种能够测量植物叶片氮素状况的无损SPAD - 502叶绿素仪在农艺作物中的应用越来越普遍。它在咖啡等园艺作物上的应用仍然相对较少。该设备能够提供快速实时的测量结果,有助于在咖啡植株出现缺氮症状之前及时提供氮肥。咖啡叶片具有叶片厚且有蜡质以及树冠层次多的特点。因此,本研究的目的是开发一种使用SPAD - 502叶绿素仪测量咖啡植株氮含量的方法,以确定阿拉比卡咖啡植株合适的氮肥施用量。•将咖啡树分为上、中、下三层。分析了SPAD值和总氮的数据。•计算了不同三层SPAD - 502值和总氮值的皮尔逊相关系数(R)、决定系数(R²)和线性回归。•结果显示,从树冠上层获取的咖啡叶片SPAD读数与其氮含量之间存在很强的相关性(R = 0.63)。这些发现可以很好地说明使用SPAD - 502叶绿素仪测量氮含量时,咖啡树冠的哪一层是更好的测量部位。