Programmable precision maize planter

管理和最小化田间试验误差对于生成高质量数据至关重要。对玉米来说，这始于土地和试验设计决策，然而种植和早期地块管理实践也起着同样重要的作用。将玉米粒种植到均匀深度和在行内精确间距的能力是至关重要的。它减少了出苗差异，几乎消除了植物之间的可变间距，这两个因素都是造成小区内变异的主要原因。我们总共种植了4万多行玉米用于实验试验，在遗传苗圃种植了7000行玉米。这4万行实验包括多地点大规模QTL研究（Lee和Lukens）、植物间竞争实验（Lee、Swanton和Tollenaar）和不同选择的种质（Lee和Tollenaar）。这类研究的关键是能够在广泛的植物密度范围内种植均匀间隔的植物（15,000至60,000株/英亩）。为了达到这些均匀的林分，需要在地块上过度种植，并物理移除幼苗，这需要大量的手工劳动。更具挑战性的是，玉米幼苗在非常早期的发育阶段就能感知到植物间的竞争信号，这使得在感知到竞争信号之前几乎不可能达到这些密度。Lee、Colasanti和Lukens共同拥有的玉米遗传苗圃的规模随着他们各自项目的发展而不断扩大。苗圃在籽粒大小、类型和形状方面代表了广泛的种质资源。遗传苗圃内的一致性也很重要，因为收集到的一些表型信息，如株高、花期、叶数等，会受到植物间竞争的影响。设备要求是一种可编程的精密播种机，它能够改变植株密度，并在一行内均匀地精确种植籽粒，无论籽粒大小，类型或形状如何。它将取代已有20年历史的“锥形”播种机，因为这种播种机无法精确地播种谷粒。

Managing and minimizing experimental error in field plots is essential for generating high-quality data. For maize, this begins with land and experimental design decisions, however planting and early plot management practices play an equally important role. The ability to plant maize kernels to a uniform depth and to a precise spacing within a row is crucial. It reduces emergence differences and virtually eliminates variable spacing between plants both major causes of within plot variability. Collectively we plant over 40,000 rows of maize for experimental trials and 7,000 rows of maize in the genetics nursery. The 40,000 rows encompass experiments involving multi-location large-scale QTL studies (Lee and Lukens), plant-to-plant competition experiments (Lee, Swanton and Tollenaar) and divergently selected germplasm (Lee and Tollenaar). Crucial for this type of research is the ability to grow uniformly spaced plants at a wide range of plant densities (15,000 to 60,000 plants/acre). To achieve these uniform stands requires over-planting the plots and physically removing young seedlings, requiring large amounts of hand labor. Even more challenging is that maize seedlings perceive plant-to-plant competition signals at an extremely early stage of development, making it virtually impossible to achieve these density stands prior to the competition signal being perceived. The maize genetics nursery shared by Lee, Colasanti and Lukens is growing in size as their respective programs grow. The nursery represents a wide array of germplasm with respect to kernel size, type and shape. Uniformity within the genetics nursery is also important, as some of the phenotypic information collected such as plant height, flowering date, leaf number can be affected by plant-to-plant competition. The equipment request is for a programmable precision planter that is capable of varying the plant density and precisely planting kernels uniformly within a row, regardless of kernel size, type or shape. It will replace the 20-year old 'cone-style' planter that is not capable of precisely planting kernels.