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A momentary increase in cytoplasmic Ca 2+ generates an oscillation responsible for the activation of proteins, such as calmodulin and kinases, which interact with reactive oxygen species (ROS) for the transmission of a stress signal. This study investigated the influence of variations in calcium concentrations on plant defense signaling and photosynthetic acclimatization after mechanical damage. Solanum lycopersicum Micro-Tom was grown with 0, 2 and 4 mM Ca 2+ , with and without mechanical damage. The expression of stress genes was evaluated, along with levels of antioxidant enzymes, hydrogen peroxide, lipid peroxidation, histochemistry, photosynthesis and dry mass of organs. The ROS production generated by mechanical damage was further enhanced by calcium-free conditions due to the inactivation of the oxygen evolution complex, contributing to an increase in reactive species. The results indicated that ROS affected mechanical damage signaling because calcium-free plants exhibited high levels of H 2 O 2 and enhanced expression of kinase and RBOH1 genes, necessary conditions for an efficient response to stress. We conclude that the plants without calcium supply recognized mechanical damage but did not survive. The highest expression of the RBOH1 gene and the accumulation of H 2 O 2 in these plants signaled cell death. Plants grown in the presence of calcium showed higher expression of SlCaM2 and control of H 2 O 2 concentration, thus overcoming the stress caused by mechanical damage, with photosynthetic acclimatization and without damage to dry mass production.

What is the relation between seed quality and food security? Here we built a summary diagram that links the development stages of the seeds with their potential of providing grain yield. This idea was tested using cowpea as a model crop, grown in a tropical environment. Initially, seed quality attributes such as water content, dry weight, germination, vigor, and longevity were characterized during seed development. With this, we were able to elucidate at which point the late maturation phase and the acquisition of seed with superior physiological quality starts. From these data, the proposed summary diagram highlighted the seed quality as a technological basis for generating a more productive plant community. It also showed that only seeds with a high-quality profile have a better chance to establishment in an increasingly challenging agricultural environment. Overall, we bring the concept that cowpea seeds with superior quality besides being the essential input for tropical agriculture is also a strategy that can contribute food security., Competing Interests: The authors have declared that no competing interests exist.

The rapid and uniform establishment of crop plants in the field underpins food security through uniform mechanical crop harvesting. In order to achieve this, seeds with greater vigor should be used. Vigor is a component of physiological quality related to seed resilience. Despite this importance, there is little knowledge of the association between events at the molecular level and seed vigor. In this study, we investigated the relationship between gene expression during germination and seed vigor in soybean. The expression level of twenty genes related to growth at the beginning of the germination process was correlated with vigor. In this paper, vigor was evaluated by different tests. Then we reported the identification of the genes Expansin-like A1 , Xyloglucan endotransglucosylase/hydrolase 22 , 65-kDa microtubule-associated protein , Xyloglucan endotransglucosylase/hydrolase 2 , N-glycosylase/DNA lyase OGG1 and Cellulose synthase A catalytic subunit 2 , which are expressed during germination, that correlated with several vigor tests commonly used in routine analysis of soybean seed quality. The identification of these transcripts provides tools to study vigor in soybean seeds at the molecular level.

Purpose: To evaluate the maximal intraluminal pressure (MIP) supported by canine cadaveric urinary bladders that underwent cystotomy followed by cystorraphy, with and without serosal patching-supplementation., Methods: Two groups (n=8 each) were formed, and in one (conventional) the cystotomy was closed with cushing pattern. In the other group (serosal), the same procedure was performed, and a piece of jejunum was used for the construction of the serosal patching over the cystorraphy. MIP was measured by means of an invasive blood pressure transducer with closed stopcock attached to a multiparameter monitor. At the end of each measurement, the bladder body circumference was assessed., Results: Mean ± SD MIP sustained for the conventional and serosal groups were 28.88 ± 5.08 and 65.38 ± 10.99 mmHg, respectively (p < 0.0001). Bladder circumference did not change significantly between groups (p = 0.35) and did not correlate with MIP assessed in conventional (p = 0.27; r = 0.4379) and serosal groups (p = 0.37; r = -0.3637)., Conclusion: Serosal patch-supplemented cystorraphies were able to sustain intraluminal pressures 55.8% higher, than nonsupplemented cystorraphies in specimens from canine cadavers.