Development of Datura metel in different pot sizes

Datura metel L. belongs to Solanaceae family and presents medicinal and ornamental potential. The use of D. metel as an ornamental plant is still unexplored, however there is a need to gather more information about this species planting, especially for pot cultivation. This study aimed to verify the effects of different pot sizes in the development of D. metel, in order to enable the use of this species in the potted flower market. The work was conducted in a greenhouse at the Biotechnology Department located at Center of Agricultural Sciences of the Federal University of Paraíba (CCA-UFPB), Areia, PB, Brazil. The experimental design used was completely randomized with 3 treatments (pot sizes: T1 = 0.82 dm3, T2 = 1.55 dm3 e T3 = 3.68 dm3) and 10 replications. The variables analyzed were: plant height, stem diameter, canopy diameter, number of ramifications, leaf length, leaf width, leaf number, flower number, flower length, flower diameter, chrolophyll a e chrolophyll b. The data obtained was submited to analysis of variance and later on clustered based Tukey’s test (5%). All the analyses were made on GENES software. There is variation between treatments for characteristics evaluated. Treatments 2 (1.55dm3) and 3 (3.68dm3) had similar values and the highest mean values for the characteristics of plant height, number of leaves and chlorophyll b. The size of the vase influences the development of the Angel’s trumpet (D. metel). Pot size influences D. metel development. The medium size recipient (1.55 dm3) is recommended for cultivation of D. metel because it presents ideal plant development, such as plant height and number of leaves, for use with ornamental species pots.

Root Foraging Precision: Do Experimental Conditions Matter?

Purpose: Root foraging precision, i.e., preferential root proliferation in nutrient-rich patches in heterogeneous soil, contributes significantly to plant nutrient acquisition. The ability to forage is usually studied experimentally, although often under different conditions. It remains unclear whether different experimental conditions affect root foraging precision. We studied the effect of experiment duration, pot size and root separation on root foraging precision and the appropriateness of using root foraging as species-specific values in databases and meta-analyses.Methods: We cultivated three perennial species in pots with spatially heterogeneous nutrient supplies and manipulated the experiment duration (4 – 10 weeks). We partly replicated the experiment in two consecutive years. In two of the three species we compared outcomes when root types were separated and unseparated, and for one species we also manipulated pot size. We assessed the effects of the manipulated factors on foraging precision expressed as the ratio of root biomass in nutrient-rich and poor patches.Results: Root foraging precision was not affected by experiment duration or pot size. Separating roots to use only the fine ones for root foraging assessment amplified foraging precision values and reduced their intraspecific variation.Conclusions: Our study investigated various methods of the root foraging research and their impact on the root foraging precision. Root foraging precision is invariable to the studied factors, therefore it is suitable as a species-specific trait, if the effect of other factors (such as nutrient patch characteristics) is taken into account.

Can Manipulation of Soil Microbiota Enhance, Stabilize and Sustain Cannabinoid Production?

Cannabis is one of the oldest cultivated crops in the history for food, fiber and drugs for thousands of years. Extension of cannabis genetic variation developed in a wide- ranging choice of varieties with various complementary phenotypes and secondary metabolites. Cannabis grow practices is very diverse, especially indoor cultivation factors, such as different lighting conditions, pot size, humidity, fertilizers. These growth factors influence a lot on the production of cannabinoids. For medical or pharmaceutical purposes, ratio of CBD or THC is very important. Plants traits and metabolic compounds are related to various conditions produced by microbes. Investigating this crosstalk between plants and microbes can play a vital role not only for stimulating the biosynthetic and signaling pathways of the host plants for the production of agronomically or pharmaceutically essential metabolic compounds but also against pathogens. This study emphasis on decoding the crosstalk between cannabis and associated microbes in the belowground environmental niches that would unravel the complexity of stabilizing cannabinoid production.

A Greenhouse Method to Evaluate Sunflower Quantitative Resistance to Basal Stalk Rot Caused by Sclerotinia sclerotiorum

Resistance of sunflower to basal stalk rot (BSR) caused by the fungus Sclerotinia sclerotiorum is quantitative, controlled by multiple genes contributing small effects. Consequently, artificial inoculation procedures allowing sufficient throughput and resolution of resistance are needed to identify highly resistant sunflower germplasm resources and to map loci contributing to resistance. The objective of this study was to develop a greenhouse-based method for evaluating sunflower quantitative resistance to BSR that would be simple, space- and time-efficient, high throughput, high resolution, and correlated with field observations. Experiments were conducted with 5-week-old sunflower plants and Sclerotinia-infested millet seed as inoculum to assess the impact of pot size and temperature and to determine the most favorable inoculum rate and placement. Subsequently, an additional experiment was performed to assess the correlation of the greenhouse inoculation procedure with field results by using a panel of 32 sunflower genotypes with known field response to BSR previously determined in multiyear, multilocation artificially inoculated trials. Experimental observations indicated that the newly developed greenhouse inoculation procedure provided improved resolution to identify highly resistant genotypes and was strongly correlated with field observations. This method will be useful for screening of sunflower experimental and breeding materials, disease phenotyping of genetic mapping populations, and evaluation of resistance to different pathogen isolates.

The leaf-feeding beetle, Cassida rubiginosa, has no impact on Carduus pycnocephalus (slender winged thistle) regardless of physical constraints on plant growth

The leaf-feeding beetle, Cassida rubiginosa, is an oligophagous biocontrol agent capable of feeding on most species in the tribe Cardueae (thistles and knapweeds). The beetle was released in New Zealand in 2007, primarily to control Cirsium arvense (Californian thistle), with the recognition that it had potential to control multiple thistle weeds. The objective of this study was to test the impact of different densities of Cassida rubiginosa larvae (0, 50, 100, or 200 per plant) on the growth and reproductive performance of the annual thistle weed, Carduus pycnocephalus (slender winged thistle). Since the effectiveness of biocontrol agents is often enhanced when plants are stressed, different levels of growth constraint were imposed by growing the weed in different pot sizes (0.5, 1, 5, and 12 litres). We hypothesised that feeding damage by Cassida rubiginosa larvae would have a greater impact on the weed when grown in smaller pots, since root growth would be constrained, and the weed’s ability to compensate for feeding damage would be restricted. Contrary to our hypothesis, pot size had no effect on feeding damage by Cassida rubiginosa on Carduus pycnocephalus. As expected, most measures of plant performance increased with larger pot sizes, including plant height, biomass, and the number of seedheads per plant. The results of this study indicate that Cassida rubiginosa is unlikely to contribute to the control of Carduus pycnocephalus. Additional oligophagous biocontrol agents targeting the rosette stage and seed production should be considered for release in New Zealand.