Submitted to: Field Crops Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/23/2004
Publication Date: 2/14/2005
Citation: Kiniry, J.R., Simpson, C.E., Schubert, A.M., Reed, J.D. 2005. Peanut leaf area index, light interception, radiation use efficiency, and harvest index at three sites in Texas. Field Crops Research. 91(2-3):297-306.
Interpretive Summary: Peanut crop growth processes need to be quantified for computer models to be able to simulate peanut yields. Stable values for growth variables for peanuts is important because of the diversity of climatic conditions in which peanuts are grown. Our objective in this study was to measure leaf area and dry weight increases of some common peanut cultivars at three sites in central and western Texas. We studied four cultivars at Stephenville, TX, and one cultivar near Gustine, TX in 2001. In 2002, we measured four cultivars at Seminole, TX. We calculated similar values for the important parameters describing peanut growth as have been reported in the literature for experiments in Florida, Australia, and Canada. At Seminole, peanut weight increases for the Low-Energy Precise Application (LEPA) irrigation treatment were greater than for any other treatment. Values describing peanut growth for the cultivars in this study and similarities between this study and values reported in the literature will aid researchers working to simulate peanut development and yield with computer models, and will aid breeders in identifying key traits critical to peanut seed yield improvement.
Technical Abstract: Stability of parameters describing crop growth processes is a major concern of modelers wanting to simulate crops and breeders wanting to compare cultivars. Parameter stability for peanuts (Arachis hypogaea L.) is important because of the diversity of climatic conditions in which peanuts are grown. Accordingly, the objective of this study was to quantify key processes for biomass and yield production of some common peanut cultivars at three sites in central and western Texas. We measured the leaf area index (LAI), the light extinction coefficient (k) for Beer's law, nitrogen and phosphorus concentrations, and the harvest index (HI) in 2001 for four cultivars at Stephenville, TX, and one cultivar near Gustine, TX. In 2002, we measured LAI, biomass, and nitrogen and phosphorus concentrations on four cultivars at Seminole, TX. Dry matter was linearly related to intercepted PAR for all the data sets. The mean radiation use efficiency (RUE) values were 1.98 g MJ**-1 at Stephenville, 1.92 at Gustine, and 2.02 at Seminole. For two cultivars, RUE at Stephenville was similar to the spray irrigation treatment's RUE at Seminole, with higher RUE values for the Low-Energy Precise Application (LEPA) irrigation treatment. Maximum LAI values ranged from 5.6 to 7.0 at Stephenville, from 5.0 to 6.2 at Seminole, and was 5.3 at Gustine. Mean k values ranged from 0.60 to 0.64 at Stephenville and was 0.77 at Gustine. The overall mean HI was 0.36, with a mean of 0.33 for Stephenville, 0.44 for Gustine, 0.53 for spray irrigation at Seminole, and 0.58 for LEPA irrigation at Seminole. Values of RUE, k, nutrient concentrations, and HI for the cultivars in this study and similarities between this study and values reported in the literature will aid modelers simulating peanut development and yield and aid breeders in identifying key traits critical to peanut grain yield improvement.