Exessive use of inorganic fertilizers in rice production systems, causes various negative effects in the environemnt, such as reducing soil fertility and increases pollution, which disturbs agricultural sustainability. Understanding raw materials for developing organic fertilizers which are cheap and adaptive to our environment, is an important study recently. Many researchers reported that brown algae could increase growth and yield of several species of plants. This due to brown algae extract contain plant growth hormone and essential elements to stimulate growth and production of plants. This article report growth and yield of rice plants suplied with mixtured extract of brown algae. Several species of brown algae were collected in coastal beach of Lombok. The seaweeds were cutted into small peaces, extracted with boiled water for 30 minute and filtered using filter whatman no.1 to get solid and liquid extract. Mixtured solid extracts were added in soil media. On the other hand, the mixtured liquid extracts were sprayed to rice plants during vegetative growth. The results shown that mixtured solid extracts increased growth and yield of rice plants. However, mixtured liquid extract did not stimulate growth and yield of rice plants. This suggests that brown algae is a potential raw material for development of organic fertilizers, which are adaptive to environment to support sustainable agriculture.

Chlorophyll is a green pigment in leaves that functions to absorb light energy for photosynthesis. The value of chlorophyll concentration in leaves indicates the health status of a plant and healthy plants will produce more fruit. The purpose of this study was to determine the effect of chemical fertilizer (CF) and solid algae fertilizer (SAF) with different doses on the concentration of chlorophyll in paddy leaves. This research is important to do to determine the potential of macroalgae in reducing the dose of chemical fertilizer use in agricultural activities. In this study, paddy plants were given four different treatments, namely control (without CF and SAF); 100% chemical fertilizer (CF); 100% solid algae fertilizer (SAF); 50% chemical fertilizers and 50% solid algae fertilizers (CF+SAF). Each treatment consisted of ten pots. The results showed that the administration of SAF in the form of a combination of SAF 50% and CF 50% had a significant effect on the increase of chlorophyll b content of the leaves of paddy plants. However, there were no significant difference in chlorophyll a content between CF and CF+SAF group. Current results show that addition of SAF could potentially increase growth quality in paddy plants due to the increase of chlorophyll b content which absorbs higher frequency of blue light for photosynthesis.

Penelitian bertujuan untuk mengetahui apakah Mikroorganisme Lokal Keong Mas mampu menggantikan peran pupuk anorganik pada tanaman kedelai. Pelaksanaan penelitian   di “Teaching and Research Farm” Fakultas Pertanian Universitas Jambi, Desa Mendalo Indah, Kecamatan Jambi Luar Kota, Kabupaten Muaro Jambi. Rancangan yang digunakan adalah Rancangan Acak Kelompok yang terdiri dari perlakuan kombinasi pupuk anorganik N,P,K dan MOL Keong Mas, yaitu K0 = 100% pupuk anorganik, K1 = 75% pupuk anorganik dan 25% MOL Keong Mas, K2 = 50% pupuk anorganik dan 50% MOL Keong Mas, K3 = 25% pupuk anorganik dan 75% MOL Keong Mas, K4 = 100% MOL Keong Mas. Hasil penelitian menunjukkan bahwa  pemberian kombinasi 50% pupuk anorganik dan 50% MOL Keong Mas memberikan hasil yang dapat menggantikan peran pupuk anorganik pada tanaman kedelai dan dapat mempertahankan hasil pada tanaman kedelai (Glycine max L.)

Excessive use of chemical fertilizer could potentially decrease soil productivity by decreasing soil microbiome diversity. In this study, we evaluated the effects of fermented seaweed fertilizer in the soil microbial community of paddy plants (Oryza sativa L.). The paddy seedlings were divided into five groups, control (C0), chemical fertilizer (CF), seaweed fertilizer (SF), chemical and seaweed fertilizer combination 50:50 (CFSF1), and chemical and fertilizer combination 75:25 (CFSF2). The CFSF1 combination showed to be the most effective in inducing plant height (83.99 ± 3.70 cm) and number of tillers (24.20 ± 4.08). After 8 weeks after transplantation, the isolated DNA from each soil treatment were subjected to 16S rRNA (v3–v4 region) next-generation sequencing. The beneficial Acidobacteriota was most abundant in CFSF1. At genus level, the nitrifying bacteria MND1 was seen to be abundant in CFSF1 and also present in other SF treatments. The genus Chujaibacter is highly abundant in CF, which potentially plays a role in denitrification resulting in soil degradation. In addition, the CFSF1-treated soils show significantly higher diversity of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). The current results could potentially contribute to the utilization of SF as a bioremediator and promoting green agriculture practice by reducing the amount of CF usage.

The application of inorganic fertilizers has been continuously increasing since last many decades globally. Farmers nowadays heavily rely on the use of inorganic fertilizers to meet the production of their farms and gardens. This becomes a concerning environmentally and also health issue. One solution is to decrease the use of inorganic fertilizers and substitute with organic fertilizers. In our previous work, we have developed macroalgae-based organic fertilizer (MbOF) which show promising results in increasing the growth and yield of various crops and plants. However, the quality of the formulated MbOF has never been accessed. In this study, we analysed the organic matter composition and heavy metal safety profile of the MbOF. Our results show that MbOF contains considerably high organic C (43.05 ± 2.56 %). The cumulative content of total-N (1.91 ± 0.78 %), P2O5 (2.20 ± 0.81 %) and K2O (2.18 ± 0.54 %) were also above 4%. Furthermore, the C/N ratio was sufficient (22.54 ± 5.81 %). In addition, heavy metal analyses also show low content of Pb (5.61 ± 0.71 ppm) and Hg (0.29 ± 0.14 ppm). Based on the results, the formulated MbOF could be employed as substitute or used together with inorganic fertilizer to get maximum benefits regarding yield and growth of crops and plants.