W Widowati
Universitas Tribhuwana Tunggadewi

Published : 2 Documents

Found 2 Documents

The Effect of Secang Wood (Caesalpinia sappan L.) Extract to Number of Iodine and Peroxide of Groundnut Cake Rusdi, UD; Widowati, W; Sudiarto, Sudiarto
ANIMAL PRODUCTION Vol 7, No 3 (2005): September
Publisher : Universitas Jenderal Soedirman, Faculty of Animal Science, Purwokerto-Indonesia

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This research aimed to analyze the ability of secang wood extract (EKS) to retain the degradation rate of iodine number and to decelerate the peroxide number the represents the occurrences of damage at groundnut cake (BKT) during its storage. Research conducted by experimental method using completely randomized design with 7x5 factoria. Number of iodine and number of peroxide of groundnut cake were assessed. Result showed that with the application of secang wood extract, a 60 days stored groundnut cake had a higher number of iodine and  lower number of peroxide compared to both, control, and BKT treated with hydroxytoluene butylated (BHT) 0.1% and benzoate natrium (NB) 0.1%.  (Animal Production 7(3): 150-155 (2005) Key Words :  Groundnut cake, Iodine,  Peroxide
The use of biochar to reduce nitrogen and potassium leaching from soil cultivated with maize Widowati, W; Asnah, A; Utomo, W H
Journal of Degraded and Mining Lands Management Vol 2, No 1 (2014)
Publisher : University of Brawjiaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (286.368 KB) | DOI: 10.15243/jdmlm.2014.021.211


Nutrient leaching is often a problem especially in tropical areas with soil fertility constraints. This study aims to reveal the effect of biochars on leaching and uptake of nitrogen and potassium from degraded soils cultivated with maize. Each of three types of biochar originated from rice husk, wood, and coconut shell, was applied to the soil placed in PVC tube at four rates (0,15, 30, and 45 t/ha). Maize was then planted in each pot. All pots received urea (135 kg N/ha), SP 36 (36 kg P2O5/ha), and KCl (110 kg K2O/ha). Twelve treatments (three biochars and four application rates) were arranged in a factorial randomized block design with three replicates. Results of the study showed interaction effects of biochar materials and biochar rates on nitrate leaching (except on day 1 to 30) and potassium, N uptake, and plant growth. On day 1-30, leaching of nitrate and potassium was reduced by biochar application. The lowest nitrate leaching was observed at rate of 45 t /ha of wood biochar, while application of 45 t/ ha coconut shell biochar resulted in the highest K leaching. Beside, wood biochar resulted in a similar nitrate leaching with that of coconut shell biochars, but nitrate leaching increased with increasing rate of biochar chaff on 30-60 HST. All biochar materials yielded a similar potassium leaching at all rates. Application of 45 t /ha biochar husk resulted in the best maize growth.