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All Journal Jurnal Ilmu Pertanian Teknotan: Jurnal Industri Teknologi Pertanian JTSL (Jurnal Tanah dan Sumberdaya Lahan) Planta Tropika Jurnal Agro Industri Perkebunan Empowerment : Jurnal Pengabdian Masyarakat AGROMIX jurnal Ilmu Pertanian (Agricultural Science) Community Empowerment Agrisintech (Journal of Agribusiness and Agrotechnology) PERTANIAN TROPIK Agroista: Jurnal Agroteknologi Amal Ilmiah: Jurnal Pengabdian Kepada Masyarakat
Valensi Kautsar, Valensi
Faculty of Agriculture, Yamagata University
Agriculture, Biological Sciences & Forestry Arts Humanities Biochemistry, Genetics & Molecular Biology Education Environmental Science Public Health Social Sciences Other

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Journal : Planta Tropika

 1 
Estimating SPAD, Nitrogen Concentration, and Chlorophyll Content in Rice Leaves using Calibrated Smartphone Digital Image Kautsar, Valensi; Faizah, Kuni; Uktoro, Arief Ika; Khasanah, Lutfiatun; Filiphus, Filiphus
PLANTA TROPIKA Vol 12, No 2 (2024)
Publisher : Department of Agrotechnology, Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/pt.v12i2.20553

Abstract

Laboratory analysis is commonly used to determine nitrogen and chlorophyll content. However, smartphones can serve as rapid, mobile, and non-destructive tools for this purpose. An equation can be created to calculate nitrogen and chlorophyll content by analyzing color parameters from digital images of rice leaves. An examination was performed on 86 rice leaf samples from the maximum tillering and mature stages. Rice leaf photos were taken with a smartphone in natural outdoor lighting. Color calibration with Spydercheckr was needed to adjust for lighting conditions. Uncalibrated and calibrated image data were analyzed to determine RGB values converted into CIELAB color space. The L*, a*, and b* values had a significant correlation with SPAD parameters, nitrogen concentration, chlorophyll a, b, and total chlorophyll content. This connection was higher after image calibration. The study found that smartphone images could predict SPAD values with 87.9% to 92.3% precision, depending on color space. Using a smartphone digital picture of L* and a* values, N content could be estimated with 84.7% and 81.9% accuracy. Average accuracy for chlorophyll a, b, and total chlorophyll content was 65% to 76%. This study shows smartphone images can estimate rice leaf SPAD and nitrogen content. 
Weeding Frequencies Improve Soil Available Nitrogen in Organic Paddy Field Maimunah, Margi Asih; Kautsar, Valensi; Bimantara, Putu Oki; Kimani, Samuel Munyaka; Utami, Asih Indah; Sabri, Riza Kurnia; Tawaraya, Keitaro; Utami, Sri Nuryani Hidayah; Purwanto, Benito Heru; Cheng, Weiguo
PLANTA TROPIKA Vol 10, No 1 (2022)
Publisher : Department of Agrotechnology, Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/pt.v10i1.12707

Abstract

Appropriate weeds control is needed against weeds constraints in field, especially the organic field. With the appropriate management, weeding would benefit the organic field not only in reducing weeds but also in increasing nitrogen (N) availability in organic rice fields. This research aims to observe soil available N changes affected by weeding frequencies in organic paddy fields. Treatments applied were five weeding frequencies (WF) such as 0 WF, 2 WF, 4 WF, 6 WF, and 8 WF, to study the effect of various weeding frequencies on soil total N and available N ( NH4+ and NO3–) in the organic rice field. The soil in the conventional field was analyzed as a comparison to organic field soil. The results showed that soil C and N contents are similar in all treatments. Meanwhile, 6 WF performed the highest soil  NH4+ among organic plots (10.36 mg N kg–1) and 8 WF enhanced soil NO3– to the highest average among all plots (10.12 mg N kg–1). The treatment of 6 WF and 8 WF also maintain the increase of soil  NH4+ to 51 days after transplanting (DAT), meanwhile 0 WF, 2 WF, and 4 WF decreased after 40 DAT. Water samples from fields inlet-outlet and river showed that  NH4+ content found in water sample was higher than NO3–. We concluded that the more frequencies of weeding applied to organic fields potentially preserved soil inorganic N longer, which is very important in supporting rice growth. 
Co-Authors Afrizal Al Ayyubi, Muhammad Azzahra, Icha Bekti, Rokhana Benito Heru Purwanto Bimantara, Putu Oki Chizuru Sato, Chizuru Dyah Ully Parwati, Wiwin Faizah, Kuni Ferhat, Amallia Filiphus, Filiphus Hironori Yasuda, Hironori Illahiyah, Ahmad Muqit Nur Ismawanto, Diky Ismiasih, Ismiasih Keitaro Tawaraya Khasanah, Lutfiatun Kimani, Samuel Munyaka Kristiyani, Cicilia Dewi Maimunah, Margi Asih Mawandha, Hangger Gahara Miwa Takei, Miwa Muhammad Andang Novianta Nadeak, Filemon Hepron Nidia Lestari Noviyanto, Amir Nusantara, Alfonsus Eka Bara Parwati, Wiwin Dyah Ully Petroningdyah, Alya Prabowo, Fajar Yulianto Purnawan Purnawan Purnawan Rokhana Dwi Bekti, Rokhana Dwi Sabri, Riza Kurnia Samsuri Tarmadja, Samsuri Satoru Sato, Satoru Silalahi, Edo Hasiholan Sri Nuryani Hidayah Utami Suparni Setyowati Rahayu Uktoro, Arief Ika Utama, Made Andy Wira Utami, Asih Indah Weiguo Cheng, Weiguo Yohana Theresia Maria Astuti, Yohana Theresia Maria Yuka Sasaki, Yuka