| || || Lal, Rohit|
| || || Influence of mucuna (mucuna pruriens) fallow crop on selected soil properties and taro yield in Taveuni, Fiji |
Institution: University of the South Pacific.
Subject: Fallowing -- Fiji -- Taveuni, Soil fertility -- Fiji -- Taveuni, Soil productivity -- Fiji -- Taveuni, Taro -- Yields -- Fiji -- Taveuni, Mucuna -- Fiji -- Taveuni
Call No.: pac S 602 .8 .L352 2013
Copyright:10-20% of this thesis may be copied without the authors written permission
Abstract: A field study was undertaken to evaluate the comparative effects of grass and mucuna fallow types over 6 and 12 months duration with additional applications of lime and rock phosphate in Taveuni, Fiji. A separate fallow trial was established to investigate the effects of 6 months grass and mucuna fallow on the yield and yield components of taro. A comparative gross margin analysis for taro grown on both the fallow types was carried out. Mucuna fallow had significantly higher (P<0.05) biomass production and accumulated higher levels of N, P, K and Ca in its foliage. However, there were no significant (P>0.05) differences between grass and mucuna fallow on the changes in soil properties over time. Under both fallow types, as the fallow duration increased from 6 to 12 months, total soil OC, N, K, bulk density and earthworm numbers increased significantly (P<0.05). Furthermore, application of lime over 12 month fallow duration significantly (P<0.05) improved soil pH and Ca levels. Application of rock phosphate had no significant (P>0.05) effect on taro yield and soil phosphorus levels under both fallow types and duration. Taro grown under mucuna fallow significantly out-yielded those grown under grass fallow system (11.8 vs. 8.8 t/ha). Overall taro grown under mucuna fallow had 33.5% higher yield than taro grown under grass fallow. Taro leaf area, plant height, leaf number and leaf length significantly differed (P<0.05) between the two fallow types at 120 DAP. Significant associations (P<0.05) were found to exist between taro yield and leaf area (r = 0.75), taro yield and leaf number (r = 0.52), and taro yield and leaf length (r = 0.32). Weed suppression in taro grown under mucuna was significantly greater (P<0.05) than that grown under natural fallow of grass.