Unmanned aerial vehicles (UAV) and the sensors they can be equipped with are becoming more technologically advanced and common place within the agricultural industry. The output analyses from UAV captured data helps drive decisions for improving input efficiency in agricultural systems, which can result in maximum return on investment and reduced environmental impact. Advances in UAV technologies provides producers with options for assessment of crucial factors impacting crop yield and quality including crop water status and nutrient stress, competition from weeds, insects, and pathogens, and soil characteristics and precision field maps. Thus, integrating UAV technologies as a component of production agriculture enables producers to identify and locate problem areas in their fields in near real time and take corrective actions once these areas are verified. UAV technologies also offers researchers with a non‐destructive, objective manner for obtaining phenotypic measurements such as height assessment, biomass estimation, canopy reflectance, and abiotic and biotic stress tolerance, which can greatly expedite field data collection for advancing germplasm with desired agronomic traits. This review covers more than a hundred articles that were obtained from the existing literature and illustrates common UAV types, common sensor types, imagery processing options, and their practical application and pitfalls in the modern agricultural industry.
Dormancy of buds is a critical developmental process that allows perennial plants to survive extreme seasonal variations in climate. Dormancy transitions in underground crown buds of the model herbaceous perennial weed leafy spurge were investigated using a 23 K element cDNA microarray. These data represent the first large-scale transcriptome analysis of dormancy in underground buds of an herbaceous perennial species. Crown buds collected monthly from August through December, over a five year period, were used to monitor the changes in the transcriptome during dormancy transitions.
Seed dormancy has been associated with red grain color in cereal crops for a century. The association was linked to qSD7-1/qPC7, a cluster of quantitative trait loci for seed dormancy/pericarp color in weedy red rice. This research delimited qSD7-1/qPC7 to the Os07g11020 or Rc locus encoding a basic helix-loop-helix family transcription factor by intragenic recombinants and provided unambiguous evidence that the association arises from pleiotropy. The pleiotropic gene expressed in early developing seeds promoted expression of key genes for biosynthesis of abscisic acid (ABA), resulting in an increase in accumulation of the dormancy-inducing hormone; activated a conserved network of eight genes for flavonoid biosynthesis to produce the pigments in the lower epidermal cells of the pericarp tissue; and enhanced seed weight. Thus, the pleiotropic locus most likely controls the dormancy and pigment traits by regulating ABA and flavonoid biosynthetic pathways, respectively. The dormancy effect could be eliminated by a heat treatment, but could not be completely overcome by gibberellic acid or physical removal of the seed maternal tissues. The dormancy-enhancing alleles differentiated into two groups basically associated with tropical and temperate ecotypes of weedy rice. Of the pleiotropic effects, seed dormancy could contribute most to the weed adaptation. Pleiotropy prevents the use of the dormancy gene to improve resistance of white pericarp cultivars against pre-harvest sprouting through conventional breeding approaches.