Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 7/22/2011
Publication Date: 11/16/2011
Citation: Angadi, S., Sultan, B., Rangappa, U., Oommen, T., Lepcha, I., Gowda, P., Contreras-Govea, F. 2011. Sorghum and legume intercropping to improve resource use efficiency of forage production systems in the Southern High Plains [abstract]. ASA-CSSA-SSSA Annual Meeting, October 16-19, 2011, San Antonio, Texas, 2011 CDROM. Interpretive Summary:
Technical Abstract: Declining water resources and the presence of large dairy and beef facilities in the Southern High Plains necessitates improving efficiency of forage production system to sustain irrigated agriculture in the region. Delayed inhabitance of interrow space by annual row cropping systems leads to inefficient use of resources like sunlight, water and nutrients. Intercropping of sorghum with beans could improve not only radiation interception and use on which dry matter accumulation is dependent, but also dry matter forage yield and quality. However, there is little information regarding intercropping of sorghum with beans in the Southern High Plains. A field experiment of intercropping of forage sorghum, [(Sorghum bicolor (L)] with two legume species [(lablab bean: Lablab purpureus (L.), pole bean (Phaseolus vulgaris L.)] was conducted at the Agricultural Science Center at Clovis, New Mexico, in 2008 and 2009 to compare the different cropping systems (sole-sorghum, sorghum-lablab, and sorghum-pole beans) for radiation interception and use, forage yield and quality. Early in the season (30 to 60 days from planting), intercepted photosynthetic active radiation (IPAR) of sorghum intercropped with beans was greater than sole-sorghum cropping by 11 to 42% and 18 to 75% depending on intercropping combinations and growing seasons, but, there was no difference among cropping systems later in the season. Sorghum-bean intercropping systems generally produced higher dry matter accumulation (DM) than sole-sorghum cropping although this was not statistically significant. This perhaps resulted from a decline in legume contribution to the total DM yield by the end of the season (10-15%, averaged over bean varieties and years). Generally, in 2009 when plants were close to forage harvesting, radiation use efficiency (RUE) of sorghum intercropped with beans was greater than RUE of sole-sorghum although the differences were not significant (3.1,3.4 and 2.7 g dry matter MJ**-1 of IPAR for sole-sorghum, sorghum-lablab, sorghum-pole bean intercropping systems, respectively). At final harvest, for example, with legumes producing significantly higher crude protein (191 to 224 vs 79 to 99 g Kg**-1 for beans and sole-sorghum, respectively), sorghum-beans intercropping systems have a potential to produce acceptable yield and quality forage and hence improve the overall RUE. However, more research would be needed in regards to the choice of density and cultivars of sorghum differing in canopy architecture so that the radiation reaching legumes and subsequent biomass contribution to total forage yield and quality are enhanced.