In order to understand the genetic diversity of oat resources and screen excellent oat germplasm materials, 21 agronomic traits of 102 oat germplasm were compared and analyzed for genetic variation, and their agronomic traits were comprehensively evaluated based on principal component analysis and cluster analysis. The results showed that spikelet shape showed the highest diversity (1.100) among the quality traits, while the 1 000-grain weight had the highest diversity index (2.053) among the quantitative traits, followed by the number of main spikelet (2.046). The coefficient of variation of infertile spikelet number reached 56.00%, and all phenotypic traits showed abundant variation. Using principal component analysis, 14 germplasm materials with excellent comprehensive traits were selected, including 340, Bayou 14, Jiaocao 1, Caoyou 1, Bayou 3, Baiyan 19, Jinyan 8, Dingyou 9, Bayou 13, Bayou 12, 469, Guyan 2, 118 and 114. The 102 oat germplasm resources were divided into 3 groups by cluster analysis. Group Ⅰ can be used as the parents of dwarf varieties; Group Ⅱ can be used as the parents of high-yield varieties for grains, and group Ⅲ can be used as the parents of high-yield varieties for forage. This study provided theoretical basis for the improvement of oat varieties and the efficient utilization of excellent germplasm.

The development of high-quality salt-tolerant wheat varieties represents a significant trend in the advancement of agricultural development in China. In this study, Dekang 961 was used as the control, and 156 high-generation wheat breeding lines and three parental materials were subjected to different concentrations (0, 75, and 150 mmol·L^-1) of NaCl stress treatments using the hydroponic method during the seedling stage. Meanwhile, high-quality specific molecular markers were used for assisted selection, combined with quality trait detection and analysis, to obtain wheat lines with strong salt tolerance at the seedling stage and excellent quality traits. The results showed that seven highly salt-tolerant materials, 42 salt-tolerant materials, 51 moderately salt-tolerant materials, 24 salt-sensitive materials, and 35 highly salt-sensitive materials were screened through cluster analysis of the comprehensive evaluation value D. Quality molecular marker identification revealed that 109 materials lack Sec-1 locus but possess the 5+10 subunit; five materials lack both the Sec-1 and Gli-D2 loci; three materials lack the Gli-D2 locus but possess the 5+10 subunit, and three materials lack both the Sec-1 and Gli-D2 loci while possess the 5+10 subunit. Comprehensive analysis led to the selection of one line with high salt tolerance and the pyramiding of three high-quality gene loci, three lines with high salt tolerance and the pyramiding of two high-quality gene loci, and three lines with high salt tolerance and the absence of the Sec-1 locus.

Leaf is an important organ for photosynthesis and a key factor affecting yield in barley. In this study, a total of 23 papers on quantitative trait loci (QTL) mapping for leaf morphological and physiological traits in barley, published from 1999 to 2023, were collected to explore the genetic mechanisms of leaf-related traits in barley. The 356 initial QTLs from different genetic populations were integrated into a high-density consensus map of barley and subjected to QTL meta-analysis. A total of 31 meta-QTLs (MQTLs) were identified. These MQTLs were unevenly distributed across the seven chromosomes, with the majority (54.8%) consisting of 3-5 initial QTLs and three MQTLs containing at least 13 initial QTLs. The average confidence interval (CI) width of these MQTLs was 1.54 cM, which is 6.73 times narrower than the average CI width of the initial QTLs. Among these 31 MQTLs, 10 breeder's MQTLs were selected for further candidate gene mining. Using the barley-rice homology comparative strategy, a total of 12 barley orthologs associated with rice leaf morphology or physiological traits were identified within the breeder's MQTL regions, which may be candidate genes for regulating leaf morphology and physiological traits in barley.

Due to the annual low average temperature, wheat stripe rust (Puccinia striiformis f.sp.tritici, Pst) could complete the annual cycle independently in Zhaosu County, Xinjiang. Meanwhile, neighboring Kazakhstan to the west, the Pst in local may have exchanges with foreign ones. Therefore, it is of great significance to identify physiological race of wheat stripe rust in this county. In this study, 100 samples of wheat stripe rust was collected from Zhaosu county, Xinjiang in 2023, which was conducted to identify physiological race, then to clarify the physiological race composition in this region. The results showed that a total of 16 physiological races were detected, among which CYR34, CYR30, Gui22-13, and Su11-2 had higher frequencies, accounting for 21.62%, 10.81%, 10.81%, and 9.45% respectively. Guinong 22 group was the dominant group, with a high frequency of 39.19%. The occurrence frequencies of strains carrying resistance genes Yr1, YrA, Yr3, Yr6, YrVir1-4, YrSu, and Yr9 were all greater than 70%. However, the available resistance genes against stripe rust include Yr3b+4b, YrJu1-4, Yr1, YrKy1-4, Yr10, Yr24/26, and Yr5.The physiological races of wheat stripe rust in Zhaosu has abundant diversity, with CYR34 race becoming prevalent in the region. Some resistant genes have basically lost their resistance in Zhaosu County.

Stomatal regulation plays a pivotal role in mitigating the impacts of abiotic stressors such as drought. It is necessary to clarify the physiological and ecological response of stomata of flag leaves to drought stress in wheat under semiarid rainfed region, which is helpful to provide guidance for dissecting traits for rapid screening indicators of drought and stress resistance varieties and exploring the improvement directions of stomatal related traits. Field experiments were conducted in two cropping seasons with 101 winter wheat genotypes under rainfed agriculture in Gansu and 3 main cultivars in Huanghuai wheat area as materials. Some indices were measured, which included stomatal distribution frequency and morphological indices, photosynthetic physiological parameters and agronomic traits of flag leaves at the mid-filling stage. The index D of stomatal character was obtained by principal component analysis and membership function method to comprehensively analyze winter wheat. The results showed that stomatal index was positively correlated with stomatal density and stomatal width, while stomatal density was negatively correlated with stomatal length. Genotype and rainfed region environment significantly affected stomatal, photosynthetic physiological, and agronomic traits．Also, the interaction between genotype and environment significantly affected the growth and development of winter wheat. Using principal component analysis, six single drought tolerance evaluation indices were transformed into three independent comprehensive indices, which reflected 84.49% of the original drought tolerance index information. The first principal component explained 37.64% of the total variation information, in which the absolute values of the load coefficients from stomatal width was the largest. The second principal component contained 26.08% of the raw information, which mainly reflected stomatal density. The third principal component played a major role in the stomatal length index, which contained 20.77% of the original information. According to the D value, the drought tolerance of the winter wheat was divided into three categories. Sixteen winter wheat varieties with strong adaptability were selected, including Lantian 131, Lantian 28, Lantian 18, and Jinmai 47, etc. The winter wheat in dryland with small, flat stomata, and high stomata density has higher leaf water use efficiency, which has sustainable yield potential in water deficient region. In summary, stomatal width, density and length can be used as the preferred indices for drought and stress resistance screening during filling stage of winter wheat. The comprehensive index D value of stomatal traits can effectively and reliably analyze the drought tolerance of winter wheat during grain filling period.

To explore the effects of sowing season and site on the antioxidant enzyme activity of barley, 48 barley varieties from Yunnan were sown continuously for two years in Dianyuan town during the four different seasons of spring, summer, autumn, and winter, and also sown at three different altitudes in Dianyuan, Xiaojie, and Yanhe town. The antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT), and polyphenol oxidase (PPO) in barley grass powder were determined by microplate reader and differential analysis was conducted. The results showed that there were significant differences in the antioxidant enzyme activity of barley planted in different seasons and at different sites. Under the conditions of four-season planting, the SOD and CAT activities of summer-planted barley grass powder were significantly higher than those of spring, autumn, and winter planting, while the PPO activity of summer planting was slightly lower than that of autumn planting, but higher than that of spring and winter planting. The SOD and CAT activities of barley grass powder at different sites were all highest at the low altitude of Yanhe town but lowest at the high altitude of Dianyuan town. The PPO activity was highest at Xiaojie town but lowest at Yanhe town. The antioxidant enzyme activity of barley grass powder was mainly affected by the planting season. Combining the membership function method and cluster analysis, the antioxidant activity of barley was evaluated, and high-quality barley varieties with high antioxidant enzyme activities were preliminarily screened (Yunpi 22, Aisi 500, Yunke 1, Yunsimai 7).

To investigate the yield characteristics and temperature and light use efficiency of early-maturing wheat varieties under late sowing after rice stubble and early harvest in the southwestern, a two-factor split-plot experiment was designed, with sowing date as the main plot namely, early sowing (S₁, 23 October), regular sowing (S₂, 30 October), late sowing for 7 d (S₃, 6 November), late sowing for 14 d (S₄, 13 November), and late sowing for 21 d (S₅, 20 November), and planting density as the split-plot (2.50×10⁶, 3.25×10⁶, 4.00×10⁶ plants·hm^-2), to study the effects of sowing date and planting density on yield and its components, dry matter accumulation and translocation, filling characteristics and temperature, light use efficiency of winter wheat. The results showed that there was no significant difference in wheat yield among S₂, S₃ and S₄, while S₁ and S₅ reduced yields by 7.6% and 32.2%, respectively, compared to S₂. There is no significant difference in yield between different planting densities. Late sowing can shorten the entire growth period of winter wheat, and reduce the effective accumulated temperature and daily average temperature before jointing. Compared with S₂, S₃, S₄ and S₅ reduced the accumulated temperature during wheat growth by 65.4, 84.1 and 93.8 ℃, and the daily average temperature by 1.3, 2.4 and 3.7 ℃, respectively. Late sowing increased the daily average temperature during jointing to booting and booting to flowering stages, reduced the effective number of spikes, and increased the number of grains per spike. Late sowing wheat has abundant temperature and light resources after flowering, manifested by an increase in daily average temperature and radiation after flowering, an increase in dry matter accumulation after flowering, an acceleration in grain filling rate, a shortened duration of grain filling, and stable grain weight. Increasing planting density increased the contribution rate of pre-flowering dry matter, reduced the duration and activity time of grain filling, and had a relatively small impact on the grain filling rate. Moderate late sowing can improve temperature use efficiency, with an increase rate of 2.24% and 8.02% for S₃ and S₄, respectively, compared to S₂. In summary, late sowing winter wheat can achieve stable yield by increasing the number of grains per ear, and the accumulation amount and transport efficiency of dry matter after flowering can be improved.

In order to explore the suitable nitrogen fertilizer management mode for wheat under wheat-rice rotation mode (rice stubble ) and wheat-soybean rotation mode (dry land ) in Chengdu Plain, Shumai 1963 was used as the material. Two nitrogen fertilizer application rates of 150(N₁) and 200 kg·hm^-2 (N₂) were set up in the field, and four nitrogen application ratios were conducted∶seedling fertilizer∶jointing fertilizer=10∶0∶0(R₁), 6∶4∶0(R₂), 6∶0∶4(R₃), 6∶2∶2(R₄), with no nitrogen fertilizer as the control (CK). The effects of different nitrogen fertilizer management modes on population quality, dry matter accumulation and translocation, and wheat yield in rice stubble and dryland wheat at the seedling stage were analyzed. The results showed that the waterlogging of wheat after rice was serious 30 days after sowing. Compared with dryland wheat, the plant height, chlorophyll content, and leaf area index of top leaves of rice-stubble wheat at the seedling stage and jointing stage were significantly reduced, the number of effective panicles was significantly reduced by 11.6%-37.2%, and the yield was significantly reduced by 14.4%-45.5%. Compared with N₁, N₂ increased the chlorophyll content and leaf area index of top leaves, dry matter accumulation, and yield at the seedling stage and jointing stage of wheat under two rotation modes, and the increase of wheat after rice was greater than that of wheat in dry land. Under N₂, the yield of rice-stubble wheat was significantly increased by 7.8%, and the yield of wheat in dry land was increased by 2.5%. Topdressing at the seedling stage (R₂) and split topdressing at the seedling + jointing stage (R₄) significantly increased the yield of wheat after rice compared with R₃ and R₁. Topdressing at the jointing stage (R₃) and split topdressing at seedling + jointing stage significantly increased the yield of dryland wheat compared with R₂ and R₁. Under the same nitrogen application rate, topdressing at the seedling stage (R₂) and topdressing at the seedling + jointing stage (R₄) significantly reduced the yield of rice-stubble wheat and dryland wheat at jointing stage. Under the conditions of rice stubble, topdressing at the seedling stage (R₂) significantly increased the dry matter translocation amount, translocation rate, and contribution rate to grain before anthesis. Under dryland conditions, topdressing at the jointing stage (R₃) and the seedling + jointing stage (R₄) significantly increased dry matter accumulation after anthesis. On the whole, the nitrogen application modes of base fertilizer∶seedling fertilizer=6∶4 and base fertilizer∶seedling stage∶jointing stage=6∶2∶2 are suitable for rice-stubble wheat in Chengdu Plain under 200 kg·hm^-2 nitrogen application rate, while the nitrogen application mode of base fertilizer∶jointing fertilizer=6∶4 and base fertilizer: seedling stage∶jointing stage=6∶2∶2 are more suitable for dryland wheat under 150 kg·hm^-2 nitrogen application rate.

In order to explore the characteristics of dry matter accumulation and N and P nutrition of high-yield (>9 000 kg·hm^-2) drip irrigation spring wheat in northern Xinjiang, a spring wheat variety Xinchun 44 was used as experimental material, and five phosphorus application（P₂O₅） treatments were set up:0 kg·hm^-2 (P0), 30 kg·hm^-2 (P1), 90 kg·hm^-2 (P2), 150 kg ·hm^-2 (P3) and 210 kg·hm^-2 (P4). The different yield levels of spring wheat in northern Xinjiang were established, and characteristics of dry matter accumulation, transport and utilization, nitrogen and phosphorus nutrition characteristics of spring wheat with different yields were analyzed. The results showed that the appropriate amount of phosphorus fertilizer can promote the accumulation, transport and distribution of dry matter, nitrogen and phosphorus nutrition characteristics and yield of spring wheat. When the phosphorus application rate increased from 0 kg·hm^-2 to 210 kg·hm^-2, the yield increased and then decreased, and reached the high yield level at 150 and 210 kg·hm^-2, ranging from 9 401.59 and 9 080.63 kg·hm^-2, respectively. Among the five phosphorus application treatments, the accumulation, transport and distribution of dry matter and the accumulation, transport and distribution of nitrogen and phosphorus were the best at 150 kg·hm^-2phosphorus application. Under the high yield levels of 150 and 210 kg·hm^-2, spring wheat had higher nitrogen production efficiency and phosphorus production efficiency, with an average of 29.98 and 94.80 kg·kg^-1. Therefore, under the drip irrigation planting mode of spring wheat in northern Xinjiang, the appropriate application amount of phosphorus fertilizer can increase the yield of spring wheat, so that high-yield spring wheat has a higher level of dry matter accumulation and transport capacity, nutrient absorption and utilization capacity, under the experimental conditions. The application amount of 150 kg·hm^-2 is the best dosage, taking the yield and nutrient utilization of spring wheat into account.

In order to investigate the effects of different control released urea on nitrogen metabolism and yield of wheat, 60 days of control released urea (SCU) and 150 days of control released urea (LCU) and normal urea (U) were used as nitrogen fertilizers. Six treatments were set up: no nitrogen fertilizer (N₀), regular fertilization (basal∶tiller∶jointing fertilizer=4∶3∶3, CK), 40% U basal fertilizer+30% SCU basal fertilizer+30% U jointing fertilizer (F₁), 40% U basal fertilizer+40% SCU basal fertilizer+20% U jointing fertilizer (F₂), 40%U+30% SCU+30% LCU as basal fertilizer (Y₁), 40% U+40% SCU+20% LCU as basal fertilizer (Y₂). Nitrogen application was consistent for all treatments except for N₀. The aim of this study was to investigate the impact of different types of urea combined application on soil inorganic nitrogen content, as well as on the activities of wheat flag leaf and grain nitrate reductase (NR), glutamine synthetase (GS), glutamine aminotransferase (GOT), and glutamine transaminase (GPT), free amino acids, soluble protein content, wheat nitrogen accumulation, yield, and nitrogen use efficiency. The results showed that compared with CK, the soil NO₃^--N and NH₄⁺-N contents during the filling period of F₂ treatment were increased by 10.67% and 4.69%, respectively; flag leaf and grain NR, GS, GOT, and GPT activities were significantly increased by 3.46%-16.55%, and free amino acid and soluble protein contents were increased by 9.95%-25.03%. The yield of the F₂ treatment was found to be significantly higher than that of CK (P<0.05), with an increase rate of 4.81%. In contrast, the Y₁ and Y₂ treatments were observed to have a significant negative impact on yield, with reduction rates of 7.59% and 4.79%, respectively, compared to CK. From the perspective of yield components, the control released fertilizer treatment resulted in a significant reduction in the number of effective spikes. The F₂ treatment led to an improvement in yield, with an increase in thousand-grain weight. Furthermore, the F₁ and F₂ treatments demonstrated a notable enhancement in nitrogen use efficiency, with the F₂ treatment exhibiting a 10.23 percentage point increase compared to CK. Under the conditions of this experiment, the best fertilization method to increase the yield and nitrogen use efficiency of wheat following rice stubble in the Jianghuai region is to apply 40% of normal urea and 40% of control released urea basally for 60 days during the release period, and 20% of normal urea retrospectively during the nodulation period, considering the level of N metabolism and nitrogen use efficiency of wheat.