Effects of phosphorus fertilizer on yield and nutritional value of sorghum (<i>Sorghum bicolor</i>) fodder at three cuttings

Abstract

An experiment was conducted to evaluate the effect of various levels of phosphorus fertilizer on the yield and nutritional value of sorghum fodder at three cuttings. The experiment was conducted by using 4 levels of Phosphorus fertilizer viz. 0 (T) 40 (T), 80 (T) and 120 (T) kg TSP/ha in a Completely Randomized Design (CRD). A significant effect (P<0.01) of phosphorus fertilizer application on plant height was observed with 80 kg TSP/ha at 60 days in 1st cutting and at 15 and 30 days in 2nd and 3rd cuttings. Highest green fodder was observed at 40 kg TSP/ha in 1st cutting but the effect was non significant. A significant effect (P<0.01) in green matter yield was observed at 80 kg TSP/ha in 2nd and 3rd cuttings. On the other hand, a significant effect (P<0.01) was observed on DM yield in first and second cuttings. Application of phosphorus fertilizer had a significant effect (P<0.01) on DM content in second cutting but non significant effect in 1st and 3rd cuttings with 80 kg TSP/ha. In 1st and 3rd cuttings, a significant difference on CP content was observed but in 2nd cutting the difference was non significant. CF, EE and P content were increased significantly in three cuttings. Highest phosphorus content was observed at 120 kg TSP/ha in each cutting. A significant effect (P<0.01) was observed on Ash content in 3rd cutting but the effect was non significant in 1st and 3rd cuttings. In 2nd cutting, IVOMD content of sorghum fodder was statistically significant but in 1st and 3rd cuttings the effect was non significant with 120 kg TSP/ha. A significant effect (P<0.01) was observed on ME content of fodder in 2nd and 3rd cuttings but the effect was non significant in 1st cutting at 120 kg TSP/ha. Based on the above findings, it may be suggested that sorghum fodder can be cultivated through the application of 80 kg TSP/ha and harvested at the age of 66 days at first cutting for maximum production.

Key words: Phosphorus; Sorghum fodder; Cuttings; Chemical composition; Metabolizable energy

DOI: http://dx.doi.org/10.3329/bjas.v39i1-2.9683

Bang. J. Anim. Sci. 2010, 39(1&2): 106-115