Respons Pertumbuhan Tanaman Sawi Hijau (Brassica juncea L.) pada Pemberian Bahan Organik Tanah dan Metode Irigasi di Lahan Pasiran Pantai

Yuanita Fifi Anggraini, Dr. Ir. Murtiningrum, S.T.P., M.Eng., IPM., ASEAN Eng.; Dr.nat.techn. Rizki Maftukhah, S.T.P., M.Sc.

2026 | Skripsi | TEKNIK PERTANIAN

Tanah berpasir memiliki kapasitas menahan air dan unsur hara yang rendah sehingga berpotensi membatasi pertumbuhan tanaman. Penelitian ini bertujuan mengevaluasi pengaruh variasi dosis pupuk kandang ayam dan metode irigasi terhadap pertumbuhan, hasil, dan produktivitas tanaman sawi hijau (Brassica juncea L.)., serta pemodelan pertumbuhan tanaman. Penelitian menggunakan Randomized Complete Block Design (RCBD) dengan dua faktor, yaitu metode irigasi (curah dan kabut) serta dosis pupuk kandang ayam (0, 2, 4, dan 6 kg/plot). Data dianalisis menggunakan uji ANOVA dua arah (Two-Way ANOVA) yang dilanjutkan dengan uji lanjut Tukey HSD pada taraf nyata lima persen, sedangkan pemodelan pertumbuhan dilakukan menggunakan model logistik. Hasil penelitian menunjukkan bahwa kombinasi irigasi kabut dan pupuk kandang ayam 6 kg/plot menghasilkan pertumbuhan dan produktivitas tertinggi pada periode tanam kedua. Perlakuan tersebut menghasilkan tinggi tanaman 25,9 cm, jumlah daun 10,0 helai, nilai SPAD 55,9, berat segar tajuk 111,7 g/tanaman, dan produktivitas 2,233 kg/m². Variasi dosis pupuk kandang ayam berpengaruh nyata (nilai p kurang dari 0,05) terhadap seluruh parameter pengamatan, sedangkan metode irigasi berpengaruh nyata terhadap kandungan klorofil, biomassa, dan berat panen. Model pertumbuhan belum mampu merepresentasikan pola pertumbuhan tanaman sawi hijau secara akurat dengan tingkat kesesuaian yang lebih baik pada parameter jumlah daun dibandingkan tinggi tanaman. Berdasarkan hasil penelitian, kombinasi irigasi kabut dan pupuk kandang ayam 6 kg/plot direkomendasikan untuk meningkatkan pertumbuhan dan produktivitas tanaman sawi hijau pada lahan berpasir.

Coastal sandy soils have a low capacity to retain water and nutrients, which can limit plant growth. This study aimed to evaluate the effects of different chicken manure application and irrigation methods on the growth, yield, and productivity of green mustard (Brassica juncea L.) cultivated in coastal sandy soil, as well as to develop mathematical plant growth model. The experiment used a Randomized Complete Block Design (RCBD) with two factors, irrigation method (sprinkler and fog irrigation) and chicken manure application rate (0, 2, 4, and 6 kg/plot). The data were analyzed using a two-way analysis of variance (ANOVA), followed by Tukey's Honestly Significant Difference (HSD) at the five percent significance level. Plant growth was modelled using a logistic growth model. The results show that the combination of fog irrigation and chicken manure applied at 6 kg/plot produced the highest growth and productivity during the second planting period. The treatment resulted in a plant height of 25,9 cm, number of leaves 10,0, SPAD value 55,9, fresh weight of the head of 111,7 g/plant, and productivity of 2,23 kg/m². Chicken manure application rate significantly affected (with p less than 0,05) all measured parameters, whereas irrigation method significantly influenced SPAD content, biomass, and fresh harvest weight. The growth model was not able to accurately represent the growth pattern of green mustard, although it provided a better fit for leaves numbers than for plant height. In conclusion, the combination of fog irrigation and chicken manure at a rate 6 kg/plot is recommended to enhance the growth and productivity of green mustard plants on coastal sandy soil.

Kata Kunci : sawi hijau, pupuk kandang ayam, irigasi kabut, irigasi curah, Two Way ANOVA, model logistik.