Netiya Karaket

Abstract This study evaluates a practical, low-cost solution for image-based leaf SPAD (Soil and Plant Analysis Development) value and chlorophyll content monitoring using a mobile phone. We compare laboratory assay and SPAD-502+ measurements with image-based estimates from a mobile phone app (PhotoFolia). Performance is tested for four commercial rice varieties grown in Thailand.

1. Introduction Thailand has approximately 1,763,575 ha of sugarcane plantations and was ranked the second-largest sugar exporter in 2021–22 []. In 2022, about 6.62 M tons of cane sugar were exported, generating a national income of about 3100 M USD []. Sugar and related products accounted for about 21% of the national gross domestic product in the agricultural sector and affected more than 425,000 households [].

1. Introduction Sustainability has been in the limelight since 2015, when the 2030 Agenda for Sustainable Development, with 17 sustainability goals, was adopted by all United Nations Member States. These goals promote responsible production and consumption, quality employment, environmental health, and adaptability to climate change.