American Journal of Potato Research最新文献

Abstract

Above-ground biomass (AGB) is one of the most important indicators for evaluating potato growth and yield. Rapid and accurate biomass estimation is of great significance to potato breeding and agricultural production. However, high cost, large data volume, and poor model scalability are the main problems of hyperspectral remote sensing and LiDAR in existing AGB measurement methods, especially in small-scale farmland. One of the important methods for solving the above problems is extracting canopy structure features through RGB images. In this study, a new AGB estimation method for potatoes at the field scale was proposed by using canopy leaf detection and digital images. First, using the improved feature fusion network and the soft intersection over union (soft-IoU) layer, an improved detection network of dense leaves, DenseNet-potato, was developed to detect canopy leaves. Second, the detection network was used to extract the canopy structural features, and the corrected number and total area of canopy leaves were obtained. Finally, multilayer perceptron (MLP) regression was introduced to build prediction models for AGB using canopy features. It was found that the DenseNet-potato network had excellent detection effects on dense canopy leaves. The mAP₅₀ and mAP₇₅ of the two detection pipelines reached 76.63% and 64.35%, respectively, which were 9.17% and 6.05% higher than the state-of-the-art RetinaNet method. In addition, the results indicated a strong correlation between the estimated and field-observed AGB using the MLP method from the digital camera dataset (R² = 0.83, RMSE = 0.039 kg/plot, NRMSE = 12.16%), while the unmanned aerial vehicle (UAV) dataset was unsatisfactory (R² = 0.62, RMSE = 0.051 kg/plot, NRMSE = 15.32%). This study can provide a reference for efficiently estimating potato AGB using RGB images.

Cheatgrass (Bromus techtorum) is an non-native grass that has invaded the natural range of the two wild potato species in the USA. We sought to detect evidence that it suppresses Solanum jamesii (jam). We grew flats of 12 cheatgrass populations and dried and stored the straw and the media containing the roots. In the following year, we again prepared flats of actively growing grass as well as flats with plain potting medium as control. One sprouted tuber of each of 35 jam populations was planted in flats of each of the 12 cheatgrass populations for each treatment: Control, Grass, Straw, and Roots. Percent shoots emerged in Root media treatment was not significantly different from Control, each at about 93%, but Grass (70%) and Straw (80%) were significantly lower than Control. The 12 cheatgrass populations inhibited jam tuber shoots compared to Control differently, as Grass (8% to 43% reduction) and as Straw (0% to 33% reduction). Subjective scores of the vigor of cheatgrass and emerged jam stands indicated that a more vigorous stand of cheatgrass is associated with less vigorous jam shoots. It appears that cheatgrass can significantly inhibit jam shoots from sprouted tubers even when growing in optimal conditions.

Potato tuber number, size and quality determine crop value. Elevated soil temperature often reduces yield and quality. Effects of cool soil are less well understood. Potatoes were grown in a greenhouse with 22 °C days and 18 °C nights. Shortly after emergence, soil temperature in some pots was lowered to 10–14 °C using cooling coils wrapped around individual pots. Soil temperature of ambient temperature controls was 17–21 °C. Tuber number and total tuber weight were determined for two chip and four fresh market varieties grown in chilled and ambient temperature soil. Tuber number with chilled soil averaged 3.2 times that of controls. Tuber weight was comparable between the two treatments. ‘Red Norland’ skin was lighter red and ‘Adirondack Blue’ skin was darker purple with chilled soil compared with controls. Skin color was unchanged for the other varieties. Overall, the data suggest that cool soil influences commercially important characteristics of potato.

While potato is an immensely important crop worldwide, its highly heterozygous, autotetraploid nature limits breeding progress. Converting potato to a diploid, inbred-hybrid crop will allow breeders to respond more quickly to changing environmental pressures and consumer demands. Breeders generate dihaploids by a cross between a cultivated tetraploid potato and a Solanum phureja inducer line, resulting in a reduction in ploidy. This cross has a low frequency of success and results in seeds of unknown ploidy. Here, we present the results of using reflectance spectroscopy analysis as a method to determine ploidy in seedlings following a cross with an inducer line. While our models showed high accuracy in determining ploidy, the specificity was insufficient for spectroscopic analysis to be a viable method for ploidy determination. These data also provide an example which suggests that, while a given phenotype distribution may shift after diploidization, breeding could be effective in making diploids that perform similarly to tetraploid varieties.

Potato (Solanum tuberosum L.) is one of the most consumed food crops in the world and plays critical roles in human and animal health. Proper nitrogen (N) management is essential to producing high tuber yield and good quality while not having detrimental impacts on the environment. Efficient in-season monitoring of plant N status can guide potato growers to apply the right amount of N fertilizer at the right time. The traditional analytical methods for monitoring are destructive, labor-intensive, time-consuming, and have poor spatio-temporal resolution. In comparison, the remote sensing (RS) technologies provide non-destructive assessments with capabilities to cover large areas with high resolution. RS monitoring employs spaceborne, airborne, and ground-based platforms with multispectral or hyperspectral sensors in which physically-based or data-driven models are used to predict and map relevant plant or agronomic measurements. However, most of the research on application of these technologies to potato N management is exploratory and not yet mature. This paper reviews 109 previously published manuscripts to provide a comprehensive review of potato reflectance characteristics, three RS platforms (spaceborne, airborne, and ground-based) and two types of optical sensors (multispectral or hyperspectral), three types of models that can predict potato N status using spectral data, how the modeling process is performed, how RS can contribute to precision N application, and challenges and future outlooks for RS technologies to be applied to commercial N management in potatoes. Overall, RS has the potential for assisting potato growers with understanding the spatio-temporal variation of their crop N status, and fine-tuning their N application to avoid excessive or unnecessary use of fertilizer, so eventually N leaching and groundwater contamination can be reduced.

Minitubers serve as an excellent starting material for disease-less and healthy Pre-Elite seed tuber production. Nevertheless, it requires an optimum choice of production technology due to the associated high costs. Optimization and economic study were carried out using three different minituber sizes and five in-row planting distances of two industrial potato genotypes (Lady Olympia “LO” and Russet Burbank “RBB”). Two years of field data on yield and yield-related traits showed that both genotypes performed better at 26 cm intra-row spacing with large minitubers (≥ 25.1 mm). Planting of ≥ 25.1 mm minitubers resulted in the highest average tuber yield in both genotypes at a narrow planting distance of 10 cm. Minitubers of 20.1–25.0 mm and ≤ 20.0 mm produced low tuber yield at any in-row planting distance since large minitubers possess a high amount of food and energy reserves, which made them suitable for commercial seed production. Regression studies revealed a sequential decrease in tuber yield with an increase in plant spacing irrespective of minituber size. Partial budget analysis suggested that large minitubers (≥ 25.1 mm) gave maximum net returns at 22 and 26 cm in LO, while an efficient intra-row distance in RBB was 18 cm. However, if RBB was sown with minitubers of 20.1–25.0 mm, it yielded the highest economic returns at wider plant spacings (22 and 26 cm). Minitubers of ≤ 20.0 mm generated minimum benefits due to the lowest tuber yield and less net economic returns. This study revealed the importance of optimization of plant density depending on minituber size and cultivars for pre-basic seed potato production.