Asam humat merupakan senyawa akhir hasil dekomposisi dan humifikasi sehingga lebih bersifat resisten. Peranan asam humat antara lain : bahan penguat untuk meningkatkan efisiensi remediasi elektrokinetik dari kontaminasi arsenik , membatasi toksisitas Cd dan Pb pada cacing tanah di dalam tanah, agen penyemen dalam matriks tanah untuk menekan degradasi lingkungan tambang mineral. Penelitian dilakukan guna mendapatkan ektrak asam humat dari kompos limbah pertanian dan peternakan. Asam humat diekstrak dari kompos dengan menggunakan asam kuat dan basa kuat. Kompos dari Kotoran ayam diharapkan menjadi solusi  limbah peternakan yang berpotensi mencemari lingkungan. Pembuatan kompos kotoran ayam dipadukan dengan limbah dan gulma pertanian seperti jerami, bonggol jagung, bonggol pisang, kulit durian dan eceng gondok. Dekomposisi dilakukan dengan bantuan biodekomposer EM4, Ragi Kompos dan Cacing tanah. Gugus fungsional yang menjadi penciri asam humat dari kompos kotoran ayam dengan beragam bahan tambahan dan biodekomposer yakni Puncak serapan 3450 - 3300 cm-1 , 2980-2920 cm-1,  1660-1630 cm-1 dan 1170-950 cm-1 . derajat humifikasi yang rendah di semua perlakuan merupakan penciri kompos dengan dengan tong berjalan efektif. EM4 paling efektif untuk meningkatakan laju dekomposisi bahan organikpada perlakuan

<p>Beragam bahan pembuat pupuk organik memiliki karakteristik fisik, kimia dan biologi yang berbeda-beda, demikan juga dengan kandungan unsur haranya. Hasil penelitian sebelumnya menunjukkan belum adanya spesifikasi jenis pupuk organik terhadap macam tanaman sayuran. Penelitian dilakukan di lahan Inceptisols Sumbang selama bulan  Juni hingga Oktober 2019 dan bertujuan untuk  mengetahui 1) tingkat efisiensi dan serapan N  berbagai jenis pupuk organik padat pada tanaman cabai, tomat dan caisin dan  2) pengaruh jenis pupuk organik padat terhadap pertumbuhan dan hasil  tanaman cabai, tomat dan caisin.  Penelitian disusun dalam rancangan petak terbagi dengan 5 jenis pupuk organik padat dan 3 jenis tanaman sayur. Hasil penelitian menunjukan bahwa pupuk organik kompos lengkap paling baik bagi produksi tanaman caisin dan pupuk kotoran ayam paling baik untuk produksi tanaman tomat dan cabai.</p>

Silicon is a beneficial nutrient that has the potential to alleviate the abiotic stress of bok choy grown under salinity stress on entisols. Indonesia has wide areas of entisol soils along its coastline, which could be planted with bok choy. However, salinity conditions pose a problem in entisol soils. The objective of this research was to evaluate the effect of silicon on the agronomic performance of bok choy grown on an Entisols under salinity stress conditions. This research was conducted at the screen house of the Faculty of Agriculture, Jenderal Soedirman University, from May to August 2019. The experimental design was a completely randomized completely block design (RCBD) consisting of 16 treatments with three replications. The treatments comprised two factors: the dosage of silicon fertilizer, which was 0, 5, 10, or 15 g pot^-1; and salinity stress, with a level of 0, 1, 2, or 3 dS m^-1pot^-1. Observed variables included plant height (cm), number of leaves (strands), leaf area (cm²), fresh shoot weight (g), dry shoot weight (g), fresh root weight (g), dry root weight (g), fresh plant weight (g), and dry plant weight (g). The results showed that the provision of silicon (Si) fertilizer from zeolite and sugarcane bagasse compost (SCB) improved plant height, number of leaves, leaf area, fresh plant weight, and dry plant weight of bok choy plants under salinity stress conditions on entisol soil. At a silicon dosage of 10 g pot^-1, fresh plant weight (production of bok choy) was 64.18% greater compared to the control. Increasing soil salinity up to 3 dS m^-1 of soil decreased the plant height and number of leaves but did not significantly affect fresh shoot weight, dry shoot weight, fresh plant weight, dry fresh plant weight, fresh root weight, or dry root weight.

The aims of this research are to know the effect of silica fertilizer (Si), salt stress and their interactions on the agronomic characteristics of tomato plants on Entisol soil. The experiment employed factorial randomized complete block design (RCBD) with 2 factors experiments i.e. level of conductivity, namely K0 = 0ds/m / pot, K1 = 1ds/m / pot, K2 = 2ds/m/pot, and K3 = 3ds/m/pot, and doses of Si fertilizer, namely S0 = 0g/pot, S1 = 5g/pot, S2 = 10g/pot, and S3 = 15 g/pot. There were 16 treatment combinations with 3 replications, in total 48 experimental unit were used. The variables observed were plant height, number of leaves, chlorophyll content, flowering age, number of flowers, number of fruits, fruit weight, and fruit volume. The application of Si fertilizer increased the number of tomato flowers. Salinity stress reduced plant height and weight of tomatoes. The interaction of silica fertilizer (Si) and salt stress influences the number of leaves and the number of flowers. The highest number of leaves was at the dose of KCl 1 ds/m/plant and silica fertilizer 5 g/plant, while the highest number of flowers was at the dose of KCl 3 ds/m/plant and silica fertilizer 10 g/plant.