Pengaruh Jenis Pupuk dan Dekomposer terhadap Pertumbuhan dan Produksi Padi Organik

The objective of the research was to study the effect of fertilizer types and decomposer on growth and yield of organic rice Field experiment was carried out in Cikarawang, Dramaga, Bogor from November 2011 to March 2012. The experiment used factorial-randomized complete block design with fertilizer combinations (15 ton chicken manure ha-1and 5 ton Tithonia diversifolia ha-1, 10 ton chicken manure ha-1 and 5 ton T. diversifolia ha-1, and 10 ton chicken manure ha-1 and 5 ton rice straw ha-1) as the first factor and decomposer application (using decomposer and without decomposer) as the second factor. Organic fertilizer types significantly affected root wet weight, nutrient content of P and K in leaves. Rice yields were not significantly different with fertilizer combinations 15 ton chicken manure ha-1 and 5 ton T. diversifolia ha-1, 10 ton chicken manure ha-1 and 5 ton T. diversifolia ha-1, and 10 ton chicken manure ha-1 and 5 ton rice straw ha-1, they were 2.28, 2.22, and 2.16 ton dry seed ha-1, respectively. Decomposer application significantly affected the number of tillers at 8 week afterplanting, leaf color at 5 weeks after planting, nutrient content of P in leaves and panicle length. Rice yield with decomposer application and without decomposer were 2.25 and 2.19 ton ha-1, respectively, and they were not different.Keywords: chicken manure, decomposer, organic rice, rice straw, Tithonia diversifoli

Rice Tolerance to Flooding Stress on Germination Stage and Early Seedling Growth under 5 cm Water Depth

Flood is one of the major environmental constraints that may harm plant productivity which requires specific mechanism to cope with stress. Flood prone area where rice is major crop to be cultivated, transplanting method on cultivation system cost high labor with consequence on low seedling survival. Direct seeding may offer solution for this condition with additional improvement needed on seed tolerant to germinate on anaerobic environment. An experiment was conducted to evaluate 23 rice varieties of tolerance to flooding stress on germination stage under 5 cm water depth. The experiment design was Nested – Randomized Complete Block Design with two factor and three replications. Result showed that rice germination under anaerobic condition was varied with Lambur has highest survival rates among others. Tolerance level was characterized from higher survival ability followed by high biomass accumulation and length of the shoot and root.Keywords: anaerobic germination, direct seedin

Utilization of amelioration and bioremediation to reduce Al stress in upland rice “Inpago 12”

The contribution of rice production in drylands (upland rice) to national rice production is still low, due to several limiting factors including limited water, low pH, and low soil fertility. This study aimed to obtain improved recommendations for amelioration and bioremediation in drylands with Al stress to enhance rice production. The upland rice variety of Inpago 12 was planted at Taman Bogo Experimental Farm, East Lampung in the first planting season of 2020. The experiment was arranged in a split-plot design with three replications. The main plot was the application of amelioration materials consisting of control (without amelioration), CaMg(CO3)2, CaCO3, and rock phosphate. The subplot was the application of bioremediation materials consisting of control (without bioremediation), biofertilizer, endophytic microbes, and citric acid. Results showed that amelioration and bioremediation on dry land with low to moderate Al stress and high Al stress did not significantly increase the growth of rice plants. However, bioremediation in the form of citric acid on land with low to moderate Al stress significantly increased grain production by 6.21% than without bioremediation. Keywords: Aluminium, dryland, limited water, rice production, low soil fertility, low p

Analysis of Non-Structural Carbohydrate in Relation with Shoot Elongation of Rice under Complete Submergence

Regulation of non-structural carbohydrates (NSCs) are important for plants in response to submergence. In this study, the difference in non-structural carbohydrates in relation with shoot elongation between Sub1A and non-Sub1A rice genotypes was investigated. Two rice genotypes, namely Inpari30 (Sub1A genotype) and IR72442 (non-Sub1A genotype), were submerged completely for 6 days and re-aerated by lowering water level up to stem base for 6 days of post submergence. In addition, non-submerged plants (control) was treated with water level up to stem base during the experiment. Photosynthesis rate decreased in both submerged Inpari30 and IR72442 genotypes 71% and 96% lower than their control, respectively. Submerged IR72442 declined Fv/Fm 15.6% lowest than its control and both control and submerged Inpari30. Investigation of the distribution of starch and soluble sugar content in plant organs suggested that shoot elongation of non-Sub1A genotype led to starch and sugar consumption that distributed faster to the new developed organ during submergence. In contrast, Sub1A genotype of Inpari30, which did not exhibit shoot elongation and showed slower NSCs distribution during submergence, performed better on post submergence by maintaining NSCs and distributing to the new developed organ faster than IR72442. These results suggest that Sub1A genotype managed elongation and NSCs during submergence more efficiently than non-Sub1A genotype

Analysis of Non-Structural Carbohydrate in Relation with Shoot Elongation of Rice under Complete Submergence

Regulation of non-structural carbohydrates (NSCs) are important for plants in response to submergence. In this study, the difference in non-structural carbohydrates in relation with shoot elongation between Sub1A and non-Sub1A rice genotypes was investigated. Two rice genotypes, namely Inpari30 (Sub1A genotype) and IR72442 (non-Sub1A genotype), were submerged completely for 6 days and re-aerated by lowering water level up to stem base for 6 days of post submergence. In addition, non-submerged plants (control) was treated with water level up to stem base during the experiment. Photosynthesis rate decreased in both submerged Inpari30 and IR72442 genotypes 71% and 96% lower than their control, respectively. Submerged IR72442 declined Fv/Fm 15.6% lowest than its control and both control and submerged Inpari30. Investigation of the distribution of starch and soluble sugar content in plant organs suggested that shoot elongation of non-Sub1A genotype led to starch and sugar consumption that distributed faster to the new developed organ during submergence. In contrast, Sub1A genotype of Inpari30, which did not exhibit shoot elongation and showed slower NSCs distribution during submergence, performed better on post submergence by maintaining NSCs and distributing to the new developed organ faster than IR72442. These results suggest that Sub1A genotype managed elongation and NSCs during submergence more efficiently than non-Sub1A genotype