The increasing of paddy production give an environmentally impact, because paddy cultivation contributes 46.2% of the total greenhouse gas emissions from agriculture. The paddy cultivation emission amounted to 76% of methane. Meanwhile, the grain produced by paddy consists of 16.3% to 28% husk with 18 to 22.3% silica. Silica contained in the soil can increase the root oxidation power of paddy, thus it will reduce methane emissions. The objective of this research was to evaluate the reduction of methan emissiom from paddy field by using silica from rice husk. This research used experiment with randomized block design and has eight treatments with three repetitions. The dose of biosilica is equivalent with 200 kg ha-1 of ameliorant in the form of ash, biochar, and compost. The methane analysis was carried out at 1, 5, 8, 12, and 15 weeks after planting. The methane was analized by GC with FID. The result of the research show that the ash produced from rice husk is the best single source of biosilica in paddy soil that can reduce methane emissions by 80.75%. The composition of ash, biochar, and compost (1:1:1) can increase the paddy growth and paddy production as well as reduce methane emissions effectively. The reduction of methane emission by giving silica into the soil is happened through the dissolved silica mechanism. The dissolved silica causes the increasing of pH and the root oxidation power of paddy. تفاصيل المقالة

Roses (Rosa hybrida L.) are prevalent ornamental flowers used as cut and sow flowers. This study aims to examine the effect of gibberellins on the acceleration of flowering of roses planted in pots in Rahma Village, South Lubuklinggau I District, Lubuklinggau City, South Sumatra (-3°018’10”, 102°054’41”) with a height of 110.5 meters above sea level, from September to December 2021. The planting media consisted of Ultisol soil, cow dung, and rice husk (1:1) of 10 kg/pot. Gallica varieties of roses are given gibberellins (GA3) sprayed every 7 days until the plants are 98 days old. Harvesting is done when the flowers are in full bloom. The first harvest is from day 57 to day 116, a total of 17 harvests. The treatment of gibberellin concentration is tested at 6 levels, namely: 0 ppm (Z0), 50 ppm (Z1), 100 ppm (Z2), 150 ppm (Z3), 200 ppm (Z4), and 250 ppm (Z5), with 4 groups and each consists of 3 pots. From the study results, it can be concluded that the administration of gibberellins (GA3) with concentrations between 50 ppm to 200 ppm accelerated flowering time between 2.88 to 10.5 days. Z3 increased the number of flowers by 32.5 buds, and Z2 produced flowers with the largest diameter of 7.16 cm. The length of the stalk and the number of petals on roses cannot be increased by giving gibberellins. For the flowering of roses, it is recommended to administer gibberellin with a concentration of 150 ppm (Z3). تفاصيل المقالة