PENINGKATAN PERTUMBUHAN TANAMAN PADI PADA TANAH SALIN-SODIK MELALUI APLIKASI AMENDEMEN GIPSUM DAN BIOCHAR SEKAM PADI-KOTORAN SAPI SERTA BIOPRIMING BENIH DENGAN BACILLUS PUMILUS DAN AZOTOBACTER CHROOCOCCUM

• Main Author: Rebecca Tiurma Siregar, Febrita
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/68179
• Institution: Institut Teknologi Bandung

The need for rice is increasing along with the population increase of Indonesia by 1% every year. However, the rice harvested area decreased by 6.33% from 2018 – 2020. The use of marginal land to increase the harvest area is one solution to this problem. Coastal land is a marginal land where 3.35% of it has the potential to be converted into agricultural land. This land is unproductive due to poor physical, chemical, and biological properties, especially high salinity. Rice plants are glycophytic plants that are sensitive to high salinity that can reduce productivity to death. Although the leaching process can decrease salinity, it takes a large amount of water followed by the leaching of soil nutrients. The attempt to optimize leaching is by adding amendments. Gypsum is commonly used because it can replace sodium or Na+ ions in the soil with Ca2+. However, with the continuous use of gypsum, the fertility of the soil will decrease. Organic amendments, namely cow dung digestate and rice husk biochar, are used to provide nutrients by increasing the organic matter needed by plants. Inoculation of rhizosphere bacteria (PGPR) on plant seeds is also an efficient approach in resistance to salinity and triggers plant growth. The study began by watering the paddy soils using a 3.5% percent saline solution, to make saline-sodic conditions. Then followed by the treatment of amendments addition. In this study, variation in the treatment of gypsum amendment was selected; 100% (G100); 80% (G80); 40% (G40); 20% (G20); and 10% (G10) of the theoretical gypsum requirement and organic amendments (BK), namely a mixture of rice husk biochar and cow dung digestate as much as 2.5% of the soil weight. The effect of the amendment addition treatment on the physicochemical characteristics of the soil on the salt leaching process was observed for 40 days before the soil was used as a plant growing medium. The effect of seed biopriming through PGPR inoculation (P) on soil physicochemical characteristics and rice growth was carried out using soil without the addition of amendments. The PGPR used in this study was a consortium of Bacillus pumilus and Azotobacter chroococcum. Growth parameters are observed during the planting period which is 112 HST. This study shows that the addition of amendments to the leaching process has a significant effect on the decrease in dissolved salts. G100 variations can optimize soil chemical characteristics such as EC decrease (75%), Na+ decrease (77%), Ca2+ increase (55%), pH decrease to 5.6, ESP decrease (93%), and SAR decrease (94%). BK variations can optimize the physical characteristics of the soil such as a decrease in density (0.865 g/cm3) and an increase in water retention capacity (85%). The highest growth of rice plants was obtained in variation BK for height (81.8 cm), chlorophyll value (2.27 mg /g), root length (14.8 ± 1.6 cm), and number of leaves (67 ± 35 / plant). P variations obtained an increase in the number of tiller (25 ± 5 /plant), biomass weight (59.02 ± 1.38 g) and grain weight gain (3.27 ± 0.17 g).