Macon Ridge Research Station, Louisiana State University AgCenter, Winnsboro, LA 71295, USA.
Sensors (Basel). 2012;12(6):7529-47. doi: 10.3390/s120607529. Epub 2012 Jun 4.
Estimating crop yield using remote sensing techniques has proven to be successful. However, sugarcane possesses unique characteristics; such as, a multi-year cropping cycle and plant height-limiting for midseason fertilizer application timing. Our study objective was to determine if sugarcane yield potential could be estimated using an in-season estimation of normalized difference vegetative index (NDVI). Sensor readings were taken using the GreenSeeker® handheld sensor from 2008 to 2011 in St. Gabriel and Jeanerette, LA, USA. In-season estimates of yield (INSEY) values were calculated by dividing NDVI by thermal variables. Optimum timing for estimating sugarcane yield was between 601-750 GDD. In-season estimated yield values improved the yield potential (YP) model compared to using NDVI. Generally, INSEY value showed a positive exponential relationship with yield (r(2) values 0.48 and 0.42 for cane tonnage and sugar yield, respectively). When models were separated based on canopy structure there was an increase the strength of the relationship for the erectophile varieties (r(2) 0.53 and 0.47 for cane tonnage and sugar yield, respectively); however, the model for planophile varieties weakened slightly. Results of this study indicate using an INSEY value for predicting sugarcane yield shows potential of being a valuable management tool for sugarcane producers in Louisiana.
利用遥感技术估算作物产量已被证明是成功的。然而，甘蔗具有独特的特点，例如多年的种植周期和植物高度限制了中期施肥的时间。我们的研究目的是确定是否可以使用季节内归一化差异植被指数（NDVI）的估算来估计甘蔗的产量潜力。 2008 年至 2011 年，在美国路易斯安那州的圣加布里埃尔和让内雷特使用 GreenSeeker®手持传感器进行了传感器读数。通过将 NDVI 除以热变量来计算季节内产量估计值（INSEY）。估算甘蔗产量的最佳时间在 601-750 GDD 之间。与使用 NDVI 相比，季节内估计的产量值提高了产量潜力（YP）模型。通常，INSEY 值与产量呈正指数关系（甘蔗产量和糖产量的 r（2）值分别为 0.48 和 0.42）。当根据冠层结构对模型进行分离时，直立品种的关系强度增加（甘蔗产量和糖产量的 r（2）值分别为 0.53 和 0.47）；但是，匍匐品种的模型略有减弱。这项研究的结果表明，使用 INSEY 值预测甘蔗产量具有成为路易斯安那州甘蔗生产者有价值的管理工具的潜力。
