Compost can increase soil water availability and nutrient uptake by plants, but it is not clear whether it can also improve the ability of plants to recover after drought stress. Tomato plants (Lycopersicon esculentum L.) were grown in sandy soil without compost or with compost either incorporated or mulched. There were two water treatments: (i) plants grown under sufficient water supply throughout the experiment and (ii) plants grown with sufficient water supply until day 33 after which water was withheld until stomatal conductance was close to zero. Compost addition increased water content at both field capacity and permanent wilting point, but only incorporated compost increased total available water. Compost addition increased shoot and root growth under well-watered and drought stressed conditions with a greater effect by incorporated compost. At sufficient water supply, the rates of photosynthesis and transpiration were similar in all treatments. Drought stressed plants with incorporated compost wilted earlier than control plants, whereas mulched compost increased water availability to plants and hence the number of days until wilting. Photosynthesis and transpiration recovered faster in plants grown with incorporated compost compared to other treatments. The rapid recovery of plants after drought with incorporated compost could be due to their greater root length.

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Background: Rural/remote blood collection can cause delays in processing, reducing PBMC number, viability, cell composition and function. To mitigate these impacts, blood was stored at 4 °C prior to processing. Viable cell number, viability, immune phenotype, and Interferon-γ (IFN-γ) release were measured. Furthermore, the lowest protective volume of cryopreservation media and cell concentration was investigated. Methods: Blood from 10 individuals was stored for up to 10 days. Flow cytometry and IFN-γ ELISPOT were used to measure immune phenotype and function on thawed PBMC. Additionally, PBMC were cryopreserved in volumes ranging from 500 µL to 25 µL and concentration from 10 × 106 cells/mL to 1.67 × 106 cells/mL. Results: PBMC viability and viable cell number significantly reduced over time compared with samples processed immediately, except when stored for 24 h at RT. Monocytes and NK cells significantly reduced over time regardless of storage temperature. Samples with >24 h of RT storage had an increased proportion in Low-Density Neutrophils and T cells compared with samples stored at 4 °C. IFN-γ release was reduced after 24 h of storage, however not in samples stored at 4 °C for >24 h. The lowest protective volume identified was 150 µL with the lowest density of 6.67 × 106 cells/mL. Conclusion: A sample delay of 24 h at RT does not impact the viability and total viable cell numbers. When long-term delays exist (>4 d) total viable cell number and cell viability losses are reduced in samples stored at 4 °C. Immune phenotype and function are slightly altered after 24 h of storage, further impacts of storage are reduced in samples stored at 4 °C.