Sweetpotato: improving crop management as dual purpose to increase food and feed on small-scale crop-livestock farmers

摘要

Sweetpotato (Ipomoea batatas) is grown for different purposes: human consumption, animal feeding,and industrial products (bio-fuel). Vines,foliage,and unsaleable or damaged roots are frequently used to feed animals in Latin America,Africa and East Asia. Demand for feed,fodder,fuel,and traditional supplements are increasing and competing with human needs. Sweetpotato (SP) offers a viable alternative to satisfy different demands by using it as a dualpurpose crop. 1172 clones were evaluated and classified by the combined criteria of root and vine relation (R/F) and vines and roots dry matter production. Among them, 19 clones were selected for animal feeding and human or industrial use. As the relation (R/V) was not consistent under selected material,therefore the roots biomass R/(V + R) was used to differentiate the proportion of roots over total biomass,Consequently,a modification of traditional crop management consisting of different cutting frequencies under saline and non saline soils was evaluated. Results showed that cuts at about 75 days of growth reduced root production by 27% while vine production was increased by 15%. increasing the total biomass by 11-19. 5%. Saline soils decreased the total biomass by 32.5% and 22.4 for 75 and 150 day cut frequency. This cutting regime provided the conservation of biomass to be used as silage,either alone or as a supplement for pig feeding as well as roots for different uses. The utilization of SP stands by grazing/foraging pigs caused no significant effect on soil structure or organic matter content,but brought about significant increments in soil nutrients:nitrogen (25%),phosphorus (50%) and potassium (41%). Grazing/foraging or confined swine fed on SP plus silage and a protein supplement showed no significant difference in weight gain between the grazing/foraging treatments but penned pigs gained 17.5% more weight (p<0. 01). Grazing/foraging and semi confinement swine feed with soybean and wheat showed no significant difference.