Dualex便携式智能气象-叶绿素-花青素-黄酮醇测量仪
 

摘氮（N）是一种经常与环境问题有关的基本元素，利用叶夹传感器来调节N施肥是一项令人感兴趣的技术。本研究旨在评估在不同氮剂量下种植的甜椒作物周期中，SPAD和Dualex测量的指标，确定SPAD和Dualex光学传感器评估氮状况的能力，并确定叶绿素指数作为产量估计器的准确性。甜椒植株移栽（DAT）后在平板上培养150天，施肥6种不同的N剂量，分为10次，每两周施用一次。在每个处理的最上部成熟叶片上，在整个周期内测量SPAD、叶绿素（CHL）、类黄酮（FLV）和氮平衡指数（NBI）。我们测定了这些叶片的氮含量和最终的商业产量。氮剂量与生长期之间存在交互作用。高达60dat的氮剂量对SPAD和CHL指数没有显著影响。FLV和NBI指数对N剂量的反应显示出相反的模式。我们发现SPAD、CHL和NBI与叶片中的氮含量以及这些指标与几个评估日期的商业产量之间存在很强的相关性。然而，我们没有观察到商业产量和FLV之间的显著相关性。这两种叶夹传感器都可以预测叶片的氮素状况和商业产量，随着作物发育的进行，这种相关性得到改善。

Application of Proximal Optical Sensors to Assess Nitrogen Status and Yield of Bell Pepper Grown in Slab
 

Abstract

Nitrogen (N) is an essential element frequently associated with environmental issues, and the utilization of leaf clip sensors to adjust N fertilization is a technology of interest. This study aimed to evaluate the indices measured with SPAD and Dualex through the bell pepper crop cycle cultivated under different N doses, to identify the ability of the SPAD and Dualex optical sensors to assess N status and establishing the accuracy of the chlorophyll indices as yield estimators. Bell pepper plants were cultivated for 150 days after transplanting (DAT) in slabs fertigated with 6 different N doses divided into 10 bi-weekly applications. The indices SPAD, chlorophyll (CHL), flavonoids (FLV), and nitrogen balance index (NBI) were measured over the cycle on the uppermost mature leaves of each treatment. We determined the N content of these leaves and the final commercial yield. An interaction effect was found between N dose and growth stage. The SPAD and CHL indices were not significantly affected by N dose up to 60 DAT. The FLV and NBI indices show an opposite pattern in response to N dose. We found a strong correlation between the SPAD, CHL, and NBI and the N content in the leaves and between these indices and commercial yield in several evaluated dates. However, we did not observe a significant correlation between commercial yield and FLV. Both leaf clip sensors could predict the N status of the leaves and the commercial yield, improving the correlation as the crop development progressed.