Crop straw returning to the field is an effective practice for straw utilization to improve soil fertility and sustain crop productivity. However, little information is available about the long-term effects of paddy straw return on soil properties and rice yield under a double-rice system. The objectives of this study were to test the hypothesis of the effects of different amounts of paddy straw returned to the field on soil physicochemical properties and rice yield, and to clarify the correlation between crop yield and soil physicochemical properties as well as quick-acting nutrients under different straw-returning modes. The experiment, initiated in the 2005 rice season, utilized “Xiang 45” and “Xiang 13” long-grained rice cultivars within a double-season rice cropping system. Three straw-returning treatments were implemented: rotary tillage with full rice straw incorporation (RTS), incorporation of one-third of the rice straw (1/3RTS), and incorporation of two-thirds of the rice straw (2/3RTS). This study found that among the three straw return rates, 2/3RTS had the most significant impact on soil physicochemical properties. Soil nitrogen content was identified as a crucial factor influencing soil organic carbon (SOC) accumulation, while pH levels significantly affected rice yield. Straw incorporation effectively increased the content and stocks of SOC.

Wheat powdery mildew and stripe rust, caused by Blumeria graminis f. sp. tritici (Bgt) and Puccinia striiformis f. sp. tritici (Pst), respectively, are two devastating diseases that threaten global wheat production. Long-term reliance on a limited number of resistance genes can accelerate resistance breakdown. Triticum urartu (2n = 14, A^uA^u), the progenitor of the wheat A subgenome, serves as a valuable gene pool for disease resistance. In this study, we identified three T. urartu accessions exhibiting high resistance to Bgt and Pst. Molecular marker analysis indicated that PI 428215 and PI 428315 carry Pm60b, whereas CITR 17664 carries both Pm60 and YrU1. Durum–T. urartu amphiploids (AABBA^uA^u) displayed resistance responses identical to their T. urartu parent and were used as bridges to transfer these resistance genes into a common wheat (AABBDD) background. Using marker-assisted selection (MAS), recurrent backcrossing, selfing, and phenotypic screening, we developed wheat lines carrying Pm60, Pm60b, YrU1, or Pm60 + YrU1. Segregation analysis in backcross-derived populations supported the functionality of these genes in the common wheat background. The selected introgression lines have high resistance to Bgt and Pst and showed no obvious adverse agronomic effects, providing useful germplasm for wheat disease resistance breeding. This study used a “multi-resistance, multi-combination” pyramiding strategy by MAS to introduce resistance genes from wild wheat into common wheat.