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Gaylussacia brachycera (box huckleberry) is a unique relict species and is the monospecific member of Gaylussacia sect. Vitis-idaea. As part of investigations to understand interspecific crossability in Gaylussacia, pollinations were made between evergreen 2x G. brachycera and deciduous 2x G. dumosa (dwarf huckleberry). The primary pollinations succeeded at a low level and produced four viable hybrids. Three of these hybrids had box huckleberry as the female, and one of them, dwarf huckleberry, as the female. Morphologically, these hybrids were distinct from the parents and were generally intermediate. The fertility of the hybrids was low, but one hybrid flowered sufficiently to allow collection of pollen and to backcross it as a male to box huckleberry. Four BC1 hybrids were produced from this cross. The F1 and BC1 hybrids were all verified using simple sequence repeat markers developed for the closely related genus Vaccinium. These hybrids are notable for being the first recorded hybrids of this rare species, G. brachycera, with any other Gaylussacia species, and these hybrids are expected to lead to a better understanding of species relationships both within Gaylussacia and between Gaylussacia and Vaccinium.
Numerous studies have highlighted the role of X-ray computed tomography (X-ray CT) in understanding root architecture. Nevertheless, setting definitive scanning parameters for diverse soils in varied container sizes remains challenging. This study investigates the influence of X-ray CT system voltage on the penetration capability in diverse soils and container sizes, focusing on two key parameters: (1) gray values, which indicate X-ray attenuation and contribute to image contrast, and (2) signal-to-noise ratio, a measure of image clarity. Five soil samples were collected from various depths within a soil profile to encompass bulk density values ranging from 1.34 to 1.84 g·cm−3 to conduct the experiment. Containers with dimensions of 6 × 6 × 6 cm³, 8 × 8 × 6 cm³, 10 × 10 × 6 cm³, 12 × 12 × 6 cm³, 14 × 14 × 6 cm³, and 16 × 16 × 6 cm³ were used. Voltage levels spanning 75 to 225 kV, in 25-kV increments, were applied to each sample. The observed gray values of the X-ray images were fitted using a logistic model of three parameters. Results showed that increasing voltage leads to enhanced penetration up to a plateau point, irrespective of soil density or container size. This plateau could potentially yield higher quality scans, given that lower voltages result in subdued gray values and reduced image contrast. Notably, it was observed that soil properties, including mineral composition, directly affect image gray values. This study established optimal voltage settings for specific soil types at fixed densities, offering valuable insights for researchers investigating soil–root interactions. Although the current findings are based on five soils, a more extensive sampling encompassing diverse soil textures and densities is necessary for a comprehensive understanding of X-ray penetration behavior across various soil types.
California is the nation’s primary producer of almonds, pistachios, and walnuts, and an important producer of rice. Because of California’s diverse cropping systems, off-target herbicide drift can be a considerable problem, particularly from aerial applications that are commonly used in flooded rice production systems. Triclopyr is an auxin-mimic type herbicide that has been commonly used in rice for many years for control of broadleaf weeds and the industry is familiar with symptoms of off-target triclopyr drift. Florpyrauxifen-benzyl is a newly registered auxin-mimic herbicide in California rice with activity on key weeds and is being rapidly adopted. Although symptoms typically are similar among auxinic herbicides, it is important to understand subtle differences and risks among these herbicides as stewardship for newly registered products. This research was conducted in 2020 and 2021 to determine the relative sensitivity of almond, pistachio, and walnut trees to simulated drift rates of florpyrauxifen-benzyl and triclopyr as well as characterize and compare symptoms caused by these two herbicides. The fractional herbicide rates tested were 1/200X, 1/100X, 1/33X, and 1/10X of the florpyrauxifen-benzyl use rate of 29.4 g·ha−1 a.i. and 1/200X, 1/100X, and 1/33X of the triclopyr use rate of 420.3 g·ha−1 a.e. Florpyrauxifen-benzyl and triclopyr herbicides were applied directly to one side of the canopy of 1- to 2-year-old almond, pistachio, and walnut trees. The general symptoms of florpyrauxifen-benzyl and triclopyr were chlorosis, chlorotic spots, leaf curling, leaf narrowing, leaf distortion, leaf malformation, leaf crinkling, shoot curling, stem coloring, stunting, terminal bud death, and twisting. The florpyrauxifen-benzyl and triclopyr injury symptoms were compared at the same fractional rates and found to be similar to each other. The herbicide injury was observed on the entire pistachio canopy, particularly on developing leaves and terminal buds. In contrast, injury symptoms on almond and walnut were more apparent on the side of the canopy to which the herbicides were applied. Symptom severity peaked at 14 days after treatment with the 1/10X florpyrauxifen-benzyl rate, when the visible injury was 16%, 48%, and 78% on almond, walnut, and pistachio, respectively. Although almond and walnut symptoms from the 1/10X florpyrauxifen-benzyl rate remained visible longer than all other treatments, all trees gradually recovered throughout the growing season. In contrast, pistachio trees did not recover fully and had injury symptoms that persisted for the remainder of the treatment year and at leaf-out the following spring. When drift occurs, it is typically at rates below 1/100X up to 1/33X of herbicide use rates. This research suggested that proper herbicide drift management practices and application precautions are likely to minimize the risk of significant injury from florpyrauxifen-benzyl drift to almond and walnut because of low injury symptoms at the typical drift rates. However, extra precautions may be needed if there are nearby pistachio orchards.
Plastic mulches made from nonbiodegradable polymers (e.g., polyethylene) provide an essential service in commercial horticultural production systems by enhancing crop productivity through weed suppression, soil moisture conservation, and moderating soil and canopy temperature conditions. Plastic mulches are particularly important in organic agriculture because weed management options are limited. Nevertheless, there is increasing concern about addressing the negative environmental impacts of plastic mulch waste. Soil-biodegradable plastic mulch (BDM) films that are designed to biodegrade in soils after incorporation are promising alternatives to nonbiodegradable plastic mulch. However, although the US organic standards technically permit the use of BDM films, no commercially available products meet National Organic Program (NOP) requirements for 100% biobased content and 90% degradation after 2 years following soil incorporation (7 Code of Federal Regulations, section 205.2). Other concerns about biodegradable film mulches include high perceived cost, esthetics, and uncertainties regarding the impacts of soil incorporation. New mulch technologies have emerged to diversify sustainable mulch options and overcome barriers associated with BDM film use in organic production. The objective of this study was to provide an overview of alternative and emerging mulch technologies, with an emphasis on biodegradable mulches, including water-based sprayable mulches such as hydromulch and foam mulch, and biobased agrotextiles. Information about how these mulch technologies contribute to organic and sustainable agriculture is provided, along with definitions, opportunities, challenges, and recommended areas for future research.
Breeding programs around the world continually collect data on large numbers of individuals. To be able to combine data collected across regions, years, and experiments, research communities develop standard operating procedures for data collection and measurement. One such method is a crop ontology, or a standardized vocabulary for collecting data on commonly measured traits. The ontology is also computer readable to facilitate the use of data management systems such as databases. Blueberry breeders and researchers across the United States have come together to develop the first standardized crop ontology in blueberry (Vaccinium spp.). We provide an overview and report on the construction of the first blueberry crop ontology and the 178 traits and methods included within. Researchers of Vaccinium species—such as other blueberry species, cranberry, lingonberry, and bilberry—can use the described crop ontology to collect phenotypic data of greater quality and consistency, interoperability, and computer readability. Crop ontologies, as a shared data language, benefit the entire worldwide research community by enabling collaborative meta-analyses that can be used with genomic data for quantitative trait loci, genome-wide association studies, and genomic selection analysis.
Ginger (Zingiber officinale Rosc.) is a valuable sciophyte crop used as a spice or fresh herb in culinary dishes and for treating medical issues such as osteoarthritis, neurological diseases, vomiting, and asthma. The demand for ginger in the United States is remarkably high; it is produced commercially and exclusively in Hawaii but can only meet ∼20% of US demand. Light for ginger growth may be more important than is often assumed, but the roles of light in ginger growth and rhizome yield are not fully understood. We hypothesized that artificial shade would produce the highest yielding ginger compared with no shade. This study evaluated the impact of different shading suited for ginger growth and rhizome yield of different cultivars grown in a high tunnel. There were three levels (0%, 22%, and 40%) of shade using RCBD design. We analyzed the overall yield (weight) of ginger and the specific yield (weight) of different rhizome parts (biological root, edible root, and seed ginger) per plant in addition to plant growth data. Data were analyzed for 2018 and 2019, and shade conditions influenced ginger growth and yield. There was no significant difference between shade conditions or cultivars, but general trends found that data differed between the two growing seasons. In 2018, Chinese White and Hawaii Yellow produced a better (higher) yield under 0% and 40% shade. However, in 2019, Chinese White and Hawaii Yellow produced the highest total yield under 22% shade, but Bubba Blue produced the highest overall yield at 0% shade.