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    A conservative pattern of water use, rather than deep or profuse rooting, is critical for the terminal drought tolerance of chickpea

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    Chickpea is mostly grown on stored soil moisture, and deep/profuse rooting has been hypothesized for almost three decades to be critical for improving chickpea tolerance to terminal drought. However, temporal patterns of water use that leave water available for reproduction and grain filling could be equally critical. Therefore, variation in water use pattern and root depth/density were measured, and their relationships to yield tested under fully irrigated and terminal drought stress, using lysimeters that provided soil volumes equivalent to field conditions. Twenty chickpea genotypes having similar plant phenology but contrasting for a field-derived terminal drought-tolerance index based on yield were used. The pattern of water extraction clearly discriminated tolerant and sensitive genotypes. Tolerant genotypes had a lower water uptake and a lower index of stomatal conductance at the vegetative stage than sensitive ones, while tolerant genotypes extracted more water than sensitive genotypes after flowering. The magnitude of the variation in root growth components (depth, length density, RLD, dry weight, RDW) did not distinguish tolerant from sensitive genotypes. The seed yield was not significantly correlated with the root length density (RLD) in any soil layers, whereas seed yield was both negatively related to water uptake between 23–38 DAS, and positively related to water uptake between 48–61 DAS. Under these conditions of terminal drought, the most critical component of tolerance in chickpea was the conservative use of water early in the cropping cycle, explained partly by a lower canopy conductance, which resulted in more water available in the soil profile during reproduction leading to higher reproductive success

    RELATIONSHIP BETWEEN OXIDANT AND ANTIOXIDANT ENZYMES STATUS IN TYPE 2 DIABETIC PATIENTS WITH NEPHROPATHY IN SAUDI POPULATION.

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     Objective: Oxidative stress has crucial role in pathogenesis of diabetic complications. Diabetic nephropathy (DN) is an important microvascular complication of diabetes and is widely recognized as the most common cause of the end-stage renal disease (ESRD) seen in clinical practice. Chemically, oxidative stress occurs as a result of increased levels of lipid peroxides and free radical intermediates, as well as a decrease in the total antioxidant capacity. This study analyzed the relationships between oxidant and antioxidant markers of DN in patients with type 2 diabetes mellitus (T2DM).Methods: A descriptive study was taken during the period from November 2016 to August 2017. The present study included 53 patients suffering from T2DM without nephropathy and 51 patients T2DM with nephropathy along with 69 age- and sex-matched healthy controls. Various biochemical parameters, antioxidant enzymes, and malondialdehyde (MDA) levels were measured and compared.Results: The glycosylated hemoglobin (HbA1c), urea, creatinine, microalbuminuria, and MDA levels were significantly increased (p<0.001), and antioxidant enzyme activities such as glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CTL) were significantly decreased (p<0.001) in T2DM with nephropathy patients followed by T2DM without nephropathy and control groups. There were a good negative correlations of HbA1c and GPx (r=−0.79), SOD (r=−0.61) and CTL (r=−0.74) (p≤0.05), whereas there was an excellent positive correlation of MDA concentration (r=0.85, p≤0.05) with HbA1c levels in diabetes with nephropathy.Conclusion: The study illustrated that, in diabetic patients, there is an increased concentration of lipid peroxides which may contribute to decreased levels of cellular antioxidant enzymes, further leading to T2DM with nephropathy. Hence, monitoring of these antioxidant enzymes and microalbuminuria parameters in the early stage of diabetic patients could be vital importance in possible preventing further development of complications. We suggest potential and new multiproperty antioxidants therapy as one of the most important treatment strategies for diabetic patients without nephropathy for the prevention and slowing of diabetic with nephropathy before reaching to ESRD
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