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This study explored the performance and physiological responses of three commercially used peanut cultivars in Australian farming systems under ambient and elevated CO2 conditions, aiming to identify the most suitable genotype for dual-purpose (grain and graze) cropping experiments. The experiment utilized an open-top chamber (OTC) facility to regulate CO2 concentrations. The elevated CO2 (EC) treatment targeted approximately 650 ± 50 µmol mol−1, while both ambient CO2 (AC) and control plots operated at a concentration of approximately 400 µmol mol−1. Notably, control plots without chambers served as a reference for current CO2 and environmental conditions. In contrast, despite having the same ambient CO2 concentration, AC plots were enclosed in chambers, allowing for plant growth comparisons with EC plots with the same environmental conditions aside from CO2 levels. The analyses revealed significant effects of CO2 enrichment on peanut plants. In particular, the EC treatment led to enhanced photosynthetic rates (20% in Kairi, 31% in Holt, and 19% in Alloway), alongside reduced stomatal conductance (−55% in Kairi, −32% in Holt, and −40% in Alloway), transpiration, and increased water use efficiency compared to AC conditions. Elevated CO2 levels positively influenced pod yields in Kairi (+41%) and Alloway (+36%). However, CO2 enrichment did not significantly alter the protein content, total phenolic content, cupric-reducing antioxidant capacity, and ferric-reducing antioxidant power of peanut plant material. Furthermore, no significant differences were observed in the phytochemical composition among the three cultivars under ambient or elevated CO2 conditions. On the other hand, analysis of the fibre structure conducted on peanut stover harvested at plant maturity suggested potential declines in feedstock quality. Based on the findings of this research, further investigations and testing, including simulated grazing trials, will be carried out to identify a single breed line suitable for dual-purpose management under future elevated CO2 conditions. [ABSTRACT FROM AUTHOR]

Inconsistent yield of subtropical table grape across seasons is often associated with low carbohydrate reserves during flowering. In an attempt to increase TNC and thus yield, sucrose was injected into treated trunks during periods of high carbohydrate demand (i.e., between budburst and flowering). Total non-structural carbohydrate (TNC) concentration dynamics were assessed in the grapevine root and trunk tissues of both control and treated vines. In the control (untreated) vines, the TNC concentration in root and trunk tissues was 13.5% and 7.5% w/dw at leaf fall and 7.2% and 3.7% w/dw at flowering, respectively. This decrease in carbohydrate reserve was estimated at ~500 g/vine and is associated with the re-establishment of the plant canopy in early spring. Carbohydrate reserves remained stable or rose slightly between flowering and harvest and recovered between crop harvest and leaf fall. In treated vines, a constantly pressurised low-pressure in situ trunk injection system (69 kPa) with 5% w/v sucrose solution over 45 days from budburst (to flowering), in each of the two seasons, delivered a widely variable amount of sucrose into each vine with variation ascribed to the amount of internal dead wood in the trunk. In the best circumstances, an average of 150 g sucrose/vine/season was injected, and sucrose-injected vines had higher trunk TNC reserve (4.1% compared to 3.6% w/dw in the control) at flowering. A δ13C (‰) analysis confirmed the presence of injected sucrose in the shoot at flowering. However, the correlation between the amount of loaded sucrose and δ13C in young shoot tissue was poor, indicative of variable partitioning patterns. Inflorescence number per vine and berry yield were markedly higher in sucrose-injected vines, but differences were not significant given the high variation between vines. The addition of KCl to the sucrose solution and use of the healthy vines are recommended to increase sucrose loading using the injection method to address inconsistent yielding of subtropical table grape. [ABSTRACT FROM AUTHOR]

Nigella sativa, an annual herbaceous flowering plant of the Ranunculaceae family, is considered an important medicinal plant due to the presence of several bioactive compounds in its seeds, including both volatile and non-volatile compounds. The cultivation of numerous genotypes of N. sativa is seen in different parts of the world with varying compositions of such chemical compounds. Since the variation in composition determines the quality grade of the seeds, this study was carried out to explore the compositional variation of twelve different genotypes of N. sativa cultivated in Central Queensland, Australia. The results showed total phenolic content (TPC), FRAP and CUPRAC (antioxidants), and thymoquinone in the range of 291–529 mg GAE/100 g DW, 703–966 mg TE/100 g DW, 2533–3416 mg TE/100 g DW, and 219–349 mg/100 g DW, respectively. The highest values of TPC, thymoquinone, FRAP, and CUPRAC were observed in genotypes AVTKS#E, AVTKS#F, AVTKS#4, and AVTKS#D, respectively. The lowest values of TPC and FRAP were observed in genotype AVTKS#24, and the CUPRAC and thymoquinone were lowest in genotype AVTKS#23 and AVTKS#1, respectively. Monomeric anthocyanins were absent in the methanolic seed extracts of all nigella genotypes. There was a strong positive correlation among the TPC, CUPRAC, and FRAP. However, despite thymoquinone being reported as a strong antioxidant in the literature, there was no significant correlation of thymoquinone with TPC or CUPRAC, and only a weak positive correlation with FRAP. Overall, the genotypes with comparatively higher values of thymoquinone, TPC, and antioxidant capacity (both FRAP and CUPRAC) showed particular potential for breeding programs. [ABSTRACT FROM AUTHOR]

Three peanut genotypes were cultivated under ambient and elevated CO2 conditions. Elevated CO2 treatment was associated with higher total phenolic content (TPC) values in the shoots and roots of all genotypes. Seeds showed lower levels of TPC compared to the other plant tissue, showing a decline in all three genotypes, and no differences between the CO2 treatments were observed. The Crude Protein (CP) content in seeds varied significantly among the genotypes, and elevated CO2 treatment was associated with mild increases (not significant) in CP of 4 and 6% in Holt and Alloway cultivars, respectively. It is worth mentioning that Kairi contained the highest CP content under elevated CO2 (29%). [ABSTRACT FROM AUTHOR]

A web mapping XYZ Tile Layer Service, such as Google Earth (GE), provides an amazing resource for the visualization of spatial data against aerial and satellite imagery with global coverage, typically at a resolution finer than 5 m. However, the increasing requirement on spatial accuracy in farm information requires a greater appreciation of the issues involved in the use of such services. Position errors can be created in the georeferencing and orthorectification of images, transformation between reference frames (datums) in map projection, e.g., using a spheroid as compared to an ellipsoid earth model, and tectonic shifts. A review is provided of these issues, and a case study is provided of the horizontal positional accuracy of web map imagery for Australian mango orchards. Positional accuracies varied from 1.804 to 6.131 m across four farms using GE 2021 imagery, between 1.556 and 3.365 m in one farm for the most recent imagery available from each of four web map providers, and from 0.806 m (in 2016) to 10.634 m (in 2003) in one farm for the period of 2003 and 2021 using the historical GE imagery resource. A procedure involving the estimation of four transformation parameters was demonstrated for the alignment of GNSS data with GE imagery. However, as the scale factor was unity and the rotational value was near zero, the use of a simple horizontal mean shift vector was recommended. Further recommendations are provided on (i) the use of web mapping services, with a comparison of the use of UAV survey imagery, and (ii) the need for metadata, particularly the date of collection, on collected position data, in the context of use in farm management information systems. [ABSTRACT FROM AUTHOR]