Intraspecific and interspecific interaction and fitness cost of stink bugs Euschistus heros, Diceraeus melacanthus, and Piezodorus guildinii in soybean.

BACKGROUND: The most common pentatomid species in soybean crops are Euschistus heros (F.), Piezodorus guildinii (W.), and Diceraeus melacanthus (D.), causing a significant reduction in yield. It is known that these stink bugs inhabit the reproductive structures of soybeans simultaneously; however, there are few studies addressing their intraguild interactions, as well as aspects of possible competition between them in plants. Thus, the interspecific and intraspecific interactions of these stink bugs were evaluated in laboratory and field conditions, throughout the duration of the instars and adulthood, including longevity, mortality, and the number of eggs per female. RESULTS: Euschistus heros had a higher competitive capacity in the interaction with D. melacanthus and P. guildinii, negatively interfering in the abundance or development (duration of instar, fertility, and mortality) of these stink bugs in soybean crops. This interference may act on the natural balance of these insect pests. Mortality of adults in interactions containing E. heros as a competitor or not showed that this species was not affected by the other species under field conditions. In the scenario where D. melacanthus was evaluated, it was observed that the presence of other species caused higher mortality in D. melacanthus. Additionally, higher P. guildiniii mortality was observed in interspecific interactions. CONCLUSION: Our results suggest that E. heros has a greater competitive ability in the soybean crop, followed by D. melacanthus and P. guildinii. Therefore, the results found justified the greater abundance of E. heros and helped to explain the increasing occurrence of D. melacanthus in soybean crops, contributing to new directions for understanding the interaction of the soybean stink bug complex. © 2023 Society of Chemical Industry.

A Comparison Between Saline and Balanced Solutions in Kidney Transplants: A Randomized Clinical Trial.

Objective This study aimed to investigate the impact of different types of intravenous fluids - normal saline (NS), lactated Ringer's solution (LR), and PlasmaLyte (PL) - on the acid-base balance and electrolyte concentration following kidney transplant, a common procedure for patients with end-stage renal disease (ESRD). Methodology A randomized controlled trial design was employed, wherein the primary parameters analyzed were postoperative pH and serum potassium levels. Postoperative concentrations of serum bicarbonate, sodium, chloride, and creatinine, as well as graft functionality, were assessed as secondary outcomes. These measurements were performed at the start and end of surgery, as well as 24 and 72 hours postoperatively. Results A total of 53 patients were included in the study and randomized into three cohorts: NS, LR, and PL, each of which showed comparability in terms of demographic and transplantation specifics. Notably, patients in the NS group exhibited a more significant decrease in pH (NS group: 7.285 ±0.098, LR group: 7.324 ±0.075, PL group: 7.7338 ±0.059) and bicarbonate levels (17.0 ±4.2, 20.9 ±2.8, 20.0 ±4.5) post 24 hours after the operation and displayed a similar pattern immediately after the surgery. However, there were no discernible differences in potassium (p=0.460), sodium (p=0.681), and chloride (p=0.321) levels across the groups. Furthermore, the study did not observe any significant differences in postoperative graft functionality. Conclusion The use of NS as the intraoperative fluid of choice led to lower pH and bicarbonate levels following kidney transplant, as compared to LR and PL. However, these results did not correlate with improvements in graft functionality.