To identify the distribution of disease resistance functional genes in Xinjiang spring wheat materials and provide materials for genetic improvement of wheat disease resistance breeding, KASP technology was employed to detect genes associated with resistance to stripe rust, leaf rust, powdery mildew, and Fusarium head blight in 549 Xinjiang spring wheat materials. The results showed that 121 materials carried five stripe rust resistance alleles with relatively high frequencies (QYrqin.nwafu-2AL, Yr29, QYrsn.nwafu-1BL, QYrqin.nwafu- 6BS, Yr78); 352 materials carried two leaf rust resistance alleles with relatively high frequencies (Lr67, Lr46); and 142 materials carried three Fusarium head blight resistance alleles with relatively high frequencies (QFhb.Hbaas-5AS, QFhb.hbaas-5AL, QFhb.caas-5AL). No presence of the five powdery mildew resistance genes (Pm12, Pm21, Pm2a, Pm5e, PmV) was detected in any of the materials. In summary, Xinjiang spring wheat varieties exhibited high frequencies of resistance genes for stripe rust, leaf rust, and Fusarium head blight, but a notable lack of resistance sources for powdery mildew. Therefore, it is crucial to focus on introducing and utilizing new powdery mildew resistant materials to improve the disease resistance breeding capacity of Xinjiang spring wheat.

To clarify the production status and limiting factors of intercropping systems in the Hetao Irrigation District, Hanggin Rear Banner, a representative area for crop cultivation in the Hetao Irrigation District, was selected as the research site for the survey. Based on 503 valid questionnaires from 24 administrative villages across eight townships of Hanggin Rear Banner, the results showed that the intercropping systems were widely applied in Hanggin Rear Banner. There were wheat/maize, wheat/sunflower, watermelon/sunflower and maize||soybean (mainly food and cash crops). The wheat/maize and wheat/sunflower relay were cropping the most prevalent, accounting for 42.5% and 23.5%, respectively. Both systems significantly improved land use efficiency, with land equivalent ratios of wheat/maize and wheat/sunflower were 1.48 and 1.29, respectively. There were two main limitations of applying intercropping in this region. On the one hand, field managements were more complex in intercropping than monocultures, with the average number of irrigations and weeding times were higher, with an average of 1.0 and 0.9 times higher than in monocropping, respectively; on the other hand, the average amount of nitrogen application in intercropping systems was 70.7% higher than in monocropping. Overall, it is necessary to further explore field management practices and fertilization strategies suitable for intercropping in the area to reduce water and fertilizer inputs. Meanwhile, the research and development of intercropping machinery, herbicides and other related production materials should be strengthened, and technical training should be carried out to enhance farmersʼ understanding of intercropping.

Using SSR molecular markers, genetic diversity and population structure analysis were conducted on 104 local tartary buckwheat germplasm resources in China. The results showed that nine pairs of highly polymorphic SSR primers amplified a total of 22 alleles in the 104 tartary buckwheat germplasm resources. The number of alleles amplified per primer pair ranged from two to four, with an average of 2.444 alleles per locus. The average values for effective allele number (N_e), Shannon’s diversity index (I), observed heterozygosity (H_o), and expected heterozygosity (H_e) were 1.820, 0.629, 0.058, and 0.401, respectively. The polymorphic information content (PIC) ranged from 0.0096 to 0.6115, with an average of 0.3312. UPGMA clustering analysis divided the 104 tartary buckwheat germplasm resources into four groups. The tartary buckwheat from Inner Mongolia, Yunnan, Guizhou, and Sichuan showed similar distributions, primarily clustered in group III and IV. Materials from other provinces were more evenly distributed, demonstrating rich genetic diversity. Population structure analysis and two-dimensional principal coordinate analysis (PCoA) further confirmed that the grouping results were largely consistent with the cluster analysis. This study further clarified the genetic diversity and phylogenetic relationships among local germplasms of tartary buckwheat, and screened 17 genetically pure germplasm materials. This provides a theoretical basis for the effective utilization of tartary buckwheat germplasm resources and the breeding of new varieties.

The combining ability and heterosis of sorghum sterile line and restorer line in spring-sown early maturing regions were studied to provide theoretical basis for the parent selection of sorghum hybrid combinations in the future. Using 31 sorghum as parent materials, 206 hybrid combinations were prepared by incomplete diallel cross design, and 13 main traits including plant height, panicle length and combining ability and heterosis of parents and their hybrid F₁ were analyzed. The results showed that there were significant differences in various traits between the sterile and restorer lines of sorghum, and the combining ability of different materials was significantly different. Among the 31 materials, Ji 64A, SX44A, Ji 5535A, Ji 5575A, HLS×125×2999, HLS Zao and Ji R4334 had more advantages in plant height, panicle length, grain weight per panicle, yield, penultimate leaf angle, penultimate width, and antepenultimate leaf angle, etc. The general combining ability of other traits was also excellent, so the six materials were ideal parents. There was a large heterosis utilization potential in the hybrid combination, but the mid-parent heterosis was not prominent. Meanwhile, the yield of the hybrid combination was affected by both additive and non-additive effects. To select excellent parents attention should be paid to the comprehensive traits and general combining ability of the parents, as well as the special combining ability and the complementary effect of the parents.

The effects of nitrogen (N) application on maize yield, root distribution, and N metabolism were analyzed under high-density planting by using the maize cultivar Xianyu 335 as material, setting up a conventional density treatment of 6.75×10⁴ plants/ha (D1) and a high-density treatment of 8.25×10⁴ plants/ha (D2), and applying N at five rates (0, 160, 220, 280, and 340 kg N/ha) per density treatment. The results indicated that with the increasing of N application rate, the maize yield showed a trend of increasing and then decreasing. The yield of D2 treatment was significantly higher than that of D1 treatment and the combination of high-density planting and optimized N application (160-220 kg N/ha) increased the yield by 39.1%-51.8% compared to conventional management. The optimized combination of N rates and planting densities increased root length, root length density, root surface area, root volume, specific root length, as well as the activities of glutamate synthase and glutamine synthetase in roots. The two enzyme activities were positively correlated with root growth distribution. In conclusion, an application of 160-220 kg/ha of N at a planting density of 8.25×10⁴ plants/ha is recommended. This combination enhances nitrogen metabolism enzyme activities, promotes root growth, and increases soil nutrient uptake, thereby improving maize yield. This can serve as a high-yield maize planting model for the Guanzhong region of Shaanxi.

To address the issues of soil structure deterioration, decreased organic carbon content, and low maize yield caused by soil wind erosion in semi-arid aeolian sandy regions, a long-term field positioning experiment was conducted in Durbod Mongolian Autonomous County, Heilongjiang Province. Four treatments were established: rotary tillage with ridging (CK), no-tillage with straw mulching for one year (T1), continuous no-tillage with straw mulching for three years (T2), and continuous no-tillage with straw mulching for seven years (T3). The effects of each treatment on soil aggregate distribution characteristics, organic carbon accumulation, and maize yield across different soil layers were analyzed. The results showed that in the 0-30 cm soil layer, compared with the other treatments, the T3 treatment significantly reduced soil bulk density and significantly increased soil moisture content. Meanwhile, the T3 treatment enhanced the percentage of >0.25 mm water-stable aggregates, the organic carbon content, and the contribution rate within these aggregates, while also increasing the mean weight diameter and geometric mean diameter. No-tillage with straw mulching significantly increased maize yield, with the increase ranging from 14.98% to 39.54% compared with the CK treatment. In summary, no-tillage combined with straw mulching helps improve soil aggregate stability, the organic carbon content of aggregates across all size classes, and maize yield in semi-arid areas, with the T3 treatment yielding the best results.

A field experiment was conducted to investigate the effects of planting densities and nitrogen application levels on the growth, biomass allocation and yields of Salvia prionitis Hance. Three planting density levels, high density (666 666 plant/ha), medium density (200 000 plant/ha), and low density (95 238 plant/ha); and three fertilization levels [no nitrogen application, low nitrogen (22.5 g/m²) and high nitrogen (45 g/m²)] were set. The results showed that both the density and nitrogen level significantly affected plant size, biomass allocation and yield of S.prionitis. However, the interaction effect only extremely significantly affected the parameters related to biomass allocation. In general, nitrogen application increased the plant height, number of flower stalks, and number of primary branches flower stalks of S.prionitis under all planting densities, and leaf length, leaf width, and plant height of the two low density treatment were greater than those of the high density treatment under all nitrogen levels. Nitrogen level did not significantly affect the root biomass ratio and root- shoot ratio of S.prionitis at medium density treatment, while the root biomass ratio and root-shoot ratio at low and high densities were significantly reduced with the increasing of nitrogen application. Under each densities, the root biomass, supporting structure biomass, total biomass, whole plant yield and root yield of S.prionitis were the greatest in the low nitrogen treatment, then followed by the high nitrogen treatment. under every nitrogen application levels, the root biomass, supporting structure biomass and total biomass of S.prionitis increased significantly with the decreasing of density, However, the whole plant yield and root yield increased significantly with the decreasing of density. In all treatments, whole plant yield and root yield of S.prionitis were the greatest at high density (666 666 plant/ha) with low nitrogen level (22.5 g/m² pure nitrogen, urea).

In order to clarify the pathogenicity and the potential risk of major corn pathogens to soybean root rot in corn-soybean inter planting, this study artificially inoculated non-co-occurring pathogens onto soybean roots and observed the symptoms in pots, and identified the infection grades of pathogens on soybean root rot. The results showed that Curvularia lunata causing corn curvularia leaf spot, Bipolaris maydis causing southern corn leaf blight, and Exserohilum turcicum causing northern corn leaf blight were non-co-occurring pathogens and could cause soybean root rot. Isolation and identification confirmed that the isolated strains were identical to the inoculated pathogens; C.lunata could cause soybean root rot up to Grade 5, B.maydis and E.turcicum could lead to soybean root rot up to Grade 3. The above results indicated that all three pathogens were causal agents of soybean root rot, and there was a potential risk of causing soybean root rot.

To analyze the genetic diversity of rice germplasm resources in the border areas of Yunnan Province and identify SSR markers closely related to major agronomic traits, a total of 376 newly collected rice germplasm resources from Yunnan (China), and its adjacent Myanmar and Laos were used as experimental materials. These resources were divided into three analysis units, and 11 phenotypic traits were investigated. Genetic diversity and association with phenotypic traits were analyzed using 27 pairs of SSR markers. Results showed that a total of 142 allelic variation loci were detected, including 100 rare allelic variation loci and nine peculiar allelic variation loci. Based on the comprehensive evaluation of six genetic diversity parameters, the scoring order of rice germplasm resources from the three analysis units was: Yunnan, China analysis unit > Myanmar analysis unit > Laos analysis unit. Among the 27 pairs of SSR markers, RM214, RM1086, RM5481, RM6089, RM1509, and RM7479 were closely associated with phenotypic traits, could explain more than 10.0% of the variation in panicle length, panicle exsertion, filled grains per panicle, unfilled grains per panicle, grains per panicle, and 1000-grain weight. Principal component analysis of phenotypic traits extracted four principal components with a cumulative contribution rate of 77.218%. A total of 36 excellent germplasm resources (comprehensive score ≥1.000) were selected. Among these, Huake, Nalei 5, and Haonuolang had a score greater than 2.000. They demonstrated potential as parents for multiple-tillering and large-panicle type, large-panicle type, and glutinous type, respectively.

Using Wanzhi 21 sesame as the experimental material, four harvesting periods of sesame leaf vegetable were set as follows: starting from the 40th day (P40), the 50th day (P50), the 60th day (P60), and the 70th day (P70) after the emergence of sesame, with the without harvesting sesame leaf vegetable as control (PCK). Through the two year continuous experiment, the effects of different harvesting periods on the main economic traits and yield of sesame leaf vegetable were studied, and a comprehensive benefit analysis was conducted. The results showed that the effects of the harvesting period of sesame leaf vegetable on the plant height, capsule axis length, effective node number, number of capsules per plant, number of seeds per capsule, and 1000-seed weight reached a significant level. The later the harvesting period of leaf vegetable, the slower the decline in the economic traits, which was specifically reflected as PCK > P70 > P60 > P50 > P40. The later the harvesting period of leaf vegetable, the higher the yield of sesame seeds, and the lower the reduction rate of seed yield. On the contrary, the earlier the sesame leaf vegetable harvesting, the higher the yield and net benefit of sesame leaf vegetables, but the lower the dry-fresh ratio of leaf vegetable. Specifically, the dry-fresh ratio showed an order of P40 < P50 < P60 < P70. The benefit from sesame seeds was just the opposite, and the later the sesame leaf vegetable harvesting, the higher the benefit from sesame seeds. The comprehensive benefit of harvesting leaf vegetable was the highest at P70 treatment, which increased by 39.06%-58.22% compared with PCK treatment. Therefore, the 70th day is the best harvesting period for sesame leaf vegetable, which can achieve the greatest comprehensive benefit of sesame cultivation.