The Potential of Legume Tree Prunings as Organic Matters for Improving Phosphorus Availability in an Acid Soil

A study that was aimed to elucidate roles of Gliricidia sepium and Tithonia diversifolia prunings and their extracted humic and fulvic acids on improving phosphorus availability and decreasing aluminum concentration in an Ultisol was conducted in a glasshouse. Thirteen treatments consisting of two prunings, six rates of pruning application (5, 7.5, 10, 20, 40 and 80 t/ha) and one control (no added prunings) were arranged in a randomized block design with four replicates. Each mixture of prunings and soil was placed in a pot containing 8 kg of soil and maize of Srikandi cultivar was grown on it for 45 days. At harvest, soil pH, P content and aluminium concentration were measured. Results of the glasshouse experiment showed that application of Gliricidia and Tithonia prunings significantly increased soil pH, reduced Alo concentration, increased Alp content, increased P availability, and increased P taken up by maize grown for 45 days. The optimum rate of both Gliricidia and Tithonia pruning should be 40 t/ha. However, at the same rate, optimum production gained by Tithonia would be higher than that of Gliricidia

Effects of Biochar and Crop Residues Application on Chemical Properties of a Degraded Soil of South Malang, and P Uptake by Maize

Low productivity of food crops on marginal dry lands of South Malang, East Java occurs due to low levels of soil fertility in the region due to low soil organic matter content and low content of available P. The purpose of this study was to evaluate the effect of the combination of biochar and plant litter on chemical properties of a degraded soil of South Malang, and P uptake by maize. The treatments tested in this study was a combination of types of biochar (sugarcane litter biochar and maize litter biochar), and the type of fresh litter (sugarcane and maize). Biochar doses applied were 0, 20 and 40 t biochar / ha, whereas the doses of fresh litters applied were 0, 40, and 80 t litter / ha. Three maize seed of BISI 2 variety was grown in each pot (treatment) for 49 days. Nine treatments were arranged in a completely randomized design with three replications. The results showed that application of litter and biochar tended to lower pH, CEC, exchangeable Ca, and total P the soil studied. The interaction of litter and biochar did not significantly increase P availability in the soil. However, application of litter and biochar also increased P uptake by maize. The best treatment for maximum increase of P availability and uptake of P was application 80 t sugarcane fresh litter / ha and 40 t maize litter biochar / ha

The Potential of Phosphate Solubilizing Bacteria Isolated From Sugarcane Wastes for Solubilizing Phosphate

Most of P in agricultural soils is in unavailable forms for plant growth. Phosphate solubilizing bacteria can increase soil P availability. This study was aimed to isolate phosphate solubilizing bacteria from sugarcane waste compost and to test ability of the isolated bacterial to dissolve phosphate. The bacteria were isolated from three types of sugarcane waste, i.e. filter cake compost, bagasse compost, and a mixture of filter cake + bagasse + trash biomass compost. The potential colony was further purified by the Pikovskaya method on selective media. Eight isolates of phosphate solubilizing bacteria were obtained from all wasted studied. Amongst them, T-K5 and T-K6 isolates were superior in dissolving P from Ca3(PO4)2 in the media studied. The two isolates were able to solubilize P with solubilizing index of 1.75 and 1.67 for T-K5 and T-K6, respectively. Quantitatively, T-K6 isolate showed the highest P solubilization (0.74 mg / L), followed by T-K5 isolate (0.56 mg / L), while the lowest P solubilization (0.41 mg / L) was observed for T-K4 isolate. The increase of soluble P was not always followed by the decrease in pH

MANFAAT BIOMASA TUMBUHAN LOKAL UNTUK MENINGKATKAN KETERSEDIAAN NITROGEN TANAH DI LAHAN KERING MALANG SELATAN

A research that was aimed to study the possible use of Mucuna pruriens, Psophocarpus tetragonolubus, Phaseolus lunatus, Dolichos lablab biomass as sources of local organic matters to improve soil fertility, and growth of maize on a Typic Tropaquent of South Malang. Six treatments, i.e. Mucuna pruriens, Psophocarpus tetragonolubus, Phaseolus lunatus, Dolichos lablab, Urea, and Control (no added legume biomass and fertilizers), were arranged in a Randomized Block Design with three replicates. Results of the study showed that the highest increase of soil N was due to addition of Phaeseolus, followed by Dolichos, Mucuna, and Psophocarpus. Application of Dolichos, Phaseolus, Psophocarpus and Mucuna could substitute 66%, 36%, 30% and 28% of N supplied by urea, respectively. The percentage of N urea recovered by maize was only 23,60%, while Dolichos and Phaseolus treatments resulted in 29,60% and 24,80% N recover

PELEPASAN NITROGEN DARI PANGKASAN POHON LEGUM PADA SISTEM BUDIDAYA PAGAR

Decomposition and nitrogen mineralization of prunings from five species of legume hedgerow trees (Calliandra calothyrsus, Peltophorum dasyrrachis, Leucaena leucocephala, Gliricidia sepium, and Flemingia congesta) in relation to the pruning quality and methods of pruning application were studied in a laboratory and in the field. N mineralization of the prunings was tested upon application to the soil in a laboratory under controlled leaching and non-leeching conditions over the period of 14 weeks. The absolute decomposition rates of the prunings was measured using litterbags placed randomly on the soil surface or incorporated in the soil in the field over the period of 8 weeks. The results showed that the contribution of decomposing pruning materials to the soil was not only associated with their quality and with the leaching conditions, but also with the method of application of the prunings in the field. The decomposition and N release rate constants of the prunings declined in the order of Gliricidia> Leucaena > Flemingia > Calliandra > Peltophorum for all experiments carried out. The effect of quality of N release from legume prunings was modified by leaching conditions. Where there was no leaching, the protein-binding capacity of polyphenols in the prunings can play an important role in controlling the rate of N release. Under leaching conditions, the combined (lignin + polyphenol)/N ratio became an important quality factor in affecting the N release. The amounts of N released from the prunings placed on the soil surface were much smaller than those released from the incorporated pruning

Effects of Application of Groundnut Biomass Compost on Uptake of Phosphorus by Maize Grown on an Ultisol of South Sulawesi

Low crop production is acid dryland area of South Sulawesi is due to low availability of P in the soils. One of alternatives that can be performed to overcome the problems of acid soils having high level of exchangeable Al, is through the addition of organic material. In the upland areas in South Sulawesi, crop rice, maize and groundnut crop residues are readily available, but the crop residues are generally only used as animal feed or even burned. This study was aimed to elucidate the effects of groundnut compost on P uptake by maize in Ultisol of Moncongloe, South Sulawesi. Eight kilograms of air dried soil was mixed with compost according to the following treatments; 0, 10, 15, 20, 25, 30, 35 and 40 t compost/ha. All pots received 200 kg/ha KCl and 300 kg Urea/ha as basal fertilizers. Two maize seeds were planted in each pot and thinned to one plant per pot after one week. At harvest maize shoot dry weight and maize root dry weight, length of maize cop, cob weight, cob diameter, weight grains per cob, P uptake by maize, P content in maize grain, soil available P were measured. Results of the study showed that groundnut compost has the ability to improve the availability of P in the soil and increase P uptake by maize grown on an Ultisol of South Sulawesi. Application of 25 t groundnut compost/ha was the optimal rate that can be used to increase P availability in an Ultisol of South Sulawesi

Humic and Fulvic Acids of Gliricidia and Tithonia Composts for Aluminium Detoxification in an Ultisol

A laboratory experiment was conducted to elucidate roles of Gliricidia sepium and Tithonia diversifolia composts and their extracted humic and fulvic acids on aluminum concentration in an Ultisol. Those composts and humic and fulvic acids extracted from them mixed with soil were arranged in a complete randomized design with three replicates, and incubated for 90 days. Al concentration and pH of the soil were measured at 0, 3, 10, 20, 30, 45, 60, 75 and 90 days after incubation. Results of the study showed that the highest decrease in exchangeable Al concentration (90.5%) was observed for Tithonia fulvic acid treatment during 90 days, followed by Tithonia compost (88.4%), Gliricidia fulvic acid (82.3%), Gliricida compost (82.2%), Tithonia humic acid (75.66%), and Gliricidia humic acid (73.46%) treatments, whereas control only decreased exchangeable Al concentration by 0.9%. The rate of change in exchangeable Al concentration was fast for the first 45 days, but it then slowed down for the second 45 days (45-90 days). This was particularly observed with organic acid treatments, whereas compost treatment still showed a subsequent decrease. Patterns of Al chelate and pH were very similar to that of exchangeable Al. It was thus concluded that roles of humic and fulvic acids in reducing exchangeable Al was only short term, whereas compost played roles in the long term

Potensi Pohon Lokal untuk Fitostabilisasi Logam Berat pada Tanah Tercemar Limbah Sianidasi Emas di Lombok Barat

The discharge of mercury amalgamation and cyanidation tailings of small-scale gold mining in West Lombok to agricultural lands caused Hg, Cd, Cu, Pb and Zn contamination. Phytostabilization may be a feasible approach for the management of contaminated sites. The objective of this study was to search for tree species that are potential for phytostabilization of soils contaminated by small-scale gold mine tailings in West Lombok, Indonesia. Results of this study showed that there were at least 28 tree species found in areas contaminated by gold cyanidatation tailing. Based on cyanide concentration, Hg concentration, and energy of above-ground parts of the identified plants, Duabanga moluccana (DM), Erythrina orientalis (DM)., and Paraserianthes falcataria (PF) were selected to study their phytostabilization potential. Results of plant growth experiment showed that the tolerance of the three species to heavy metals was in the order of Zn > Pb > Cu > Cd. The highest concentration of Cd (0.9 mg/kg) was found in the roots of DM. The highest concentration of Cu (37,7 mg/kg) was found in roots of EO. Roots of PF contained the highest concentrations of Pb (37.7 mg/kg) and Zn (546 mg/kg). The three plant species had metal shoot / metal root ratios of less than one. This indicates that Duabanga moluccana, Paraserianthes falcataria, and Erythrina orientalis are suitable for phytostabilization of Cu, Pb, Cd, and Zn in gold cyanidation tailing contaminated soils of West Lombok, Indonesi

Fitoekstrasi Merkuri dari Tanah Tercemar Limbah Tambang Emas Skala Kecil dan Pengaruhnya pada Pertumbuhan Tanaman Jagung

In West Lombok, gold amalgamation tailings are commonly discharged to agricultural lands resulting in reduced maize yield in the area. Phytoremediation can represent a low-cost alternative to traditional techniques such as soil removal. This study was aimed to elucidate the potential of Lindernia crustacea (L.) F., Paspalum conjugatum L., and Cyperus kyllingia Endl., for phytoremediation of mercury-contaminated soils in conjunction with the ammonium thiosulphate to phytoextract mercury and its effect on maize growth. Each of the plant seedlings was planted in a plastic pot containing 15 kg of mercury-contaminated soil for 9 weeks. Treatments tested were three plant species), and two rates of ammonium thiosulphate application, i.e. 0 and 8 g / kg of soil. Ammonium thiosulphate was applied one week before harvesting the plants. At harvest (9 weeks) shoots and roots were analyzed for mercury concentration. The remaining soils in the pots were used to grow maize for 8 weeks. The results showed that on average, the addition of ammonium thiosulphate increased the accumulation of mercury in plant shoots and roots by 82% and 47%, respectively, compared to the media without addition of ammonium thiosulphate. In comparison to the control treatment, the average increase of dry weight of maize (shoot+root) grown on media previously remediated with three plant species with addition of ammonium thiosulphate was 40%, while that grown on media previously remediated with three plant species without addition of ammonium thiosulphate was 62%