ABSTRACT
Different cropping patterns have their own economic and ecological significance. Developing cropping patterns suitable for local conditions is needed to protect and make good use of black soils. At present, the cropping patterns and their spatial characteristics in the black soil region of Northeast China is poorly understood. Based on the crop classification data in 2017-2019, we used geo-information Tupu methods, distribution index model, and bivariate spatial autocorrelation to examine the cropping patterns. The results showed that: 1) The main cropping patterns in the black soil region of Northeast China were continuous maize cropping, continuous rice cropping, continuous soybean cropping, and maize-soybean rotation, accounting for 38.3%, 18.5%, 10.3% and 26.0%, respectively. The maize-soybean rotation included maize-soybean two-year rotation, maize-maize-soybean three-year rotation, and soybean-soybean-maize three-year rotation, accounting for 44.1%, 34.5% and 21.4% of the rotation area, respectively. 2) Various cropping patterns had obviously horizontal differentiation. For instance, continuous maize cropping had very obvious gradient differentiation characteristics in temperature and humidity, but soybean continuous cropping and maize-soybean rotation showed no gradient differentiation, while continuous rice cropping had gradient differentiation only in humidity. 3) Various cropping patterns had obviously spatial clustering characteristics. They had spatial transition characteristics from soybean continuous cropping, soybean-soybean-maize three-year rotation, maize-soybean two-year rotation, maize-maize-soybean three-year rotation, to continuous maize cropping. The cropping pattern in black soil region of Northeast China was dominated by continuous cropping. Understanding its distribution pattern can provide a basis for future spatial optimization of crop rotation.
Subject(s)
Fabaceae , Oryza , Agriculture/methods , China , Soil , Glycine max , Zea maysABSTRACT
Dilated cardiomyopathy (DCM) is the leading cause of morbidity and mortality in diabetic patients. Long noncoding RNA plasmacytoma variant translocation 1 (PVT1) has been shown to be related to the pathogenesis of DCM. However, the mechanism by which PVT1 regulates DCM pathogenesis is unclear. High glucose level was employed to construct a DCM cell model in vitro. Cell viability was determined via cell counting kit-8 assay. The level of lactate dehydrogenase (LDH) was measured with the corresponding kit. Expression levels of PVT1, miR-23a-3p, and caspase-10 (CASP10) messenger RNA were evaluated with a quantitative real-time polymerase chain reaction. Cell apoptosis was assessed by flow cytometry assay. Protein levels of B-cell lymphoma 2-associated X (Bax), cleaved-caspase-3 (cleaved-casp-3), and CASP10 were examined via western blot analysis. The relationship between PVT1 or CASP10 and miR-23a-3p was verified with dual-luciferase reporter assay. We observed that PVT1 and CASP10 were upregulated while miR-23a-3p was downregulated in high glucose-induced cardiomyocytes. High glucose levels repressed cardiomyocyte activity and induced cardiomyocyte apoptosis, but this influence was antagonized by PVT1 knockdown or miR-23a-3p overexpression. Furthermore, PVT1 acted as a sponge for miR-23a-3p, and miR-23a-3p inhibition counterbalanced the influence of PVT1 silencing on viability and apoptosis of cardiomyocytes under high glucose level treatment. PVT1 could increase CASP10 expression via sponging miR-23a-3p. In conclusion, PVT1 acted as a deleterious lncRNA in DCM. PVT1 facilitated cardiomyocyte death by regulating the miR-23a-3p/CASP10, which offered a new mechanism to comprehend the pathogenesis of DCM.
