To investigate the effects of priming treatments on the germination and physiological characteristics of wheat seeds and to screen the optimal priming method for wheat seeds with low germination ability, Jimai 325 seeds with a germination rate of 32.67% after artificial aging treatment were used as the research object. Nine priming agents from three categories, including PEG 6000, gibberellic acid (GA3), and Vitamin B1 (VB1), were applied at different concentrations for soaking durations of 8 h, 16 h, and 24 h. The study examined the effects of various priming treatments on germination indicators, such as germination potential, germination rate, germination index, electrical conductivity, and the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). The results showed that all priming treatments significantly enhanced the germination capacity of aged wheat seeds. The priming agents had significant impacts on germination potential, germination rate, and germination index, with VB1 and VB2 showing the best priming effects. As the priming time was extended, the germination potential, germination rate, and germination index of wheat seeds all significantly increased, with the effects of 16 h and 24 h being significantly better than those of 8 h. By measuring the leachate electrical conductivity and the activities of SOD, POD, and CAT for priming combinations that increased the germination rate to over 85%, it was determined that soaking in 0.08% VB1 for 16 h is the optimal priming method for Jimai 325 wheat seeds with an initial germination rate of 32.67%.
To investigate the characteristics of aerial roots in maize inbred lines with different genetic backgrounds and their relationship with lodging resistance, 56 maize inbred lines were used as experimental materials. Eight aerial root traits were comprehensively analyzed using correlation analysis, path analysis, and cluster analysis. Stalk anti-thrust was measured using a plant stem strength tester as an evaluation index for lodging resistance, and the relationship between aerial root traits and lodging resistance was analyzed. The results showed that the coefficients of variation (CV) for all aerial root traits were relatively large, with the CV of the aerial root angle being the largest (31.70%) and that of the aerial root emergence time being the smallest (10.77%). Among the aerial root traits, all except emergence time and puncture resistance exhibited significant correlations with one another. Specifically, the number of aerial roots and the aerial root anchoring radius were highly significantly and positively correlated with stalk anti-thrust, with correlation coefficients of 0.560 and 0.522, respectively. Additionally, aerial root puncture resistance and the number of aerial root tiers also showed significant positive correlations with stalk anti-thrust. Path analysis indicated that both the direct and indirect effects of the number of aerial roots and the aerial root anchoring radius on the lodging resistance evaluation indicators were relatively large. Therefore, strengthening the selection and improvement of these two traits in lodging resistance breeding would help enhance the lodging resistance of maize varieties. Cluster analysis classified the tested inbred lines into four groups. Inbred lines in Group II, such as Xun M6968 and LH190, were characterized by high mean values for both stalk anti-thrust and aerial root traits, providing a germplasm foundation for the breeding of new lodging-resistant varieties.
As a commonly used bulk medicinal material in China, Astragalus membranaceus has seen increasing demand in recent years. However, the breeding and propagation of superior varietals are relatively weak, and currently cultivated varietals are inconsistent in quality and suffer from severe degeneration. Therefore, the breeding of superior strains of A.membranaceus is crucial for promoting the high-quality and sustainable development of the industry. In this study, using field-cultivated A. membranaceus as material, three new strains were bred from 2013 to 2023 using the “mass selection method” of systematic breeding based on agronomic traits such as stem color, pod characteristics, seed characteristics, and the number of leaflets. A systematic comparative analysis was conducted on their agronomic traits and active pharmaceutical ingredients (APIs). The results showed that strains 13-1 and 13-2 had green stems and pods, while 13-3 had anthocyanins-purple stems and light red pods. Strain 13-2 had the highest number of leaflets (27.9) and seeds (4.5). The fresh root yield of strain 13-2 was greater than that of 13-1 and 13-3 in the Weiheyanchuan and Beishan ecological areas; however, the yield of 13-3 was greater than that of 13-2 and 13-1 in the Southern Eryinshan area. Moreover, the disease incidence of 13-2 was lower than that of the other two strains in all three ecological areas. Additionally, 13-2 had the highest content of extracts and astragaloside IV, with the content of calycosin- 7-O-glucoside 2.6 times that specified in the Pharmacopoeia of the Peopleʼs Republic of China. Comprehensive analysis indicates that 13-2 performs better in agronomic traits, APIs, yield, and disease resistance, and has potential for application and promotion. This study also lays a foundation for the breeding of superior new varietals of A.membranaceus by providing germplasm material.
This study used wild Solanum torvum Swartz. as rootstock and cultivated eggplant Solanum melongena L. Yunqie 9 as scion. The grafting method was cleft grafting. The structure of graft union at 0, 2, 4, 6, 8, 10, and 12 days after grafting was observed, and physiological indicators such as phenylalanine ammonia lyase (PAL), peroxidase (POD), superoxide dismutase (SOD), and soluble protein (SP) were measured to study the tissue structure and physiological characteristics during healing process after eggplant grafting. The results showed that the healing process of grafting between S. torvum Swartz. and Yunqie 9 could be divided into four stages, including isolation layer and callus formation stage (0-4 d), callus division and proliferation connection stage (5-7 d), cambium connection stage (8-9 d), vascular tissue differentiation and formation stage (10-12 d). The physiological indicators measured within 12 days after grafting showed that the changes in physiological characteristics of grafted seedlings and self-grafted seedlings were basically consistent. Among them, PAL activity showed an overall downward trend, SOD activity showed a “V” shaped change of first decreasing and then increasing, while POD activity and SP content showed an “M” shaped change. In addition, there were significant changes in most physiological indicators at four days after grafting; After six days, the SOD activity of all treatments showed an overall increase, and the increasing trend of SOD activity in grafted seedlings was more pronounced, with a difference of 19 times between the highest and lowest values; During the 6th to 8th days, the SP content of grafted seedlings rapidly increased and reached its highest value on the 8th day, which was 5.6 times the lowest value. In summary, the healing process between S. torvum Swartz. and Yunqie 9 could be basically completed 12 days after grafting, and the key healing time points might be 4, 6, and 8 days after grafting.
Microbial agents are a novel type of fertilizer that can promote the growth and development of plant roots, and they have an important impact on improving nutrient absorption and yield formation in crops. However, their effects on rice grain quality remain unclear. This study used two conventional japonica rice varieties, Nanjing 9108 and Huaidao 5, as experimental materials to investigate the effects of two microbial agents of Bacillus subtilis (BS) and Trichoderma harzianum (TH) on rice grain quality under field cultivation conditions. The results showed that compared with the treatment without microbial agent (CK), the application of the BS and TH had no significant effect on the processing quality of rice. However, the BS treatment reduced the chalkiness rate by 5.5%-5.7% in Nanjing 9108 and 6.3%-7.2% in Huaidao 5, with a slightly decrease in chalkiness degree. The TH treatment significantly reduced the chalkiness rate by 7.7%-12.0% in Nanjing 9108 and 9.3%-11.1% in Huaidao 5, while the chalkiness degree decreased significantly by 10.3%-10.6% and 12.4%-12.5%, respectively. In a two-year experiment, the BS treatment decreased the taste value of two varieties to varying degrees, while the TH treatment increased it, reaching a significant level in 2022. Additionally, after microbial agent application, the amylose content of the rice decreased, while gel consistency and protein content increased. The peak viscosity and breakdown value of rice flour increased, whereas the setback value decreased. In conclusion, the application of B. subtilis and T. harzianum microbial agents contributed to improving the appearance and nutritional quality of rice. Furthermore, T. harzianum also enhanced the taste value of rice.
To elucidate the effects of nitrogen application rate and N-P-K ratio on the source-sink characteristics of small-seed hybrid rice, a field experiment was conducted using the small-seed hybrid rice variety Zhuoliangyou 0985 as material. The experiment involved four nitrogen application levels [120 (N1), 150 (N2), 180 (N3), and 210 kg/ha (N4)] and three NPK ratios [1.0:0.5:0.8 (F1), 1.0:0.5:1.0 (F2), and 1.0:1.0:1.0 (F3)]. The results showed that leaf area index (LAI), high-efficiency LAI, relative content of chlorophyll (SPAD values), and dry matter accumulation increased with increasing nitrogen application rate. There were no significant differences between N3 and N4 treatments, but both were significantly higher than the N1 treatment. Among different N-P-K ratios, the F3 treatment generally resulted in higher values, though the differences were not significant. Total spikelets and total sink capacity increased with the increase of nitrogen application rate, and the available filled ratio of sink capacity followed the order of N1 > N3 > N2 > N4. Under different N-P-K ratios, the effective filling degree of sink capacity was generally the highest in F2, though the difference was not significant. Effective panicles increased with the increase of nitrogen application rate, while the number of grains per panicle initially increased and then decreased. Both seed-setting rate and 1000-grain weight decreased with the increase of nitrogen application rate, but these differences did not reach a significant level. Yield showed a trend of first increasing and then decreasing with the increase of nitrogen application, with the N3 treatment producing the highest yield. Among the interaction treatments, N3F2 achieved the highest yield, followed by N3F1. Correlation analysis indicated that LAI, high-efficiency LAI, leaf SPAD value, dry matter accumulation, total spikelets, total sink capacity, and effective panicles were extremely significantly and positively correlated with yield. The available filled ratio of sink capacity and seed-setting rate were negatively correlated with yield, while the number of grains per panicle was significantly and positively correlated with yield. No significant correlations were found between 1000-grain weight, grain-leaf ratio, and yield. Under the conditions of this experiment, N3F1 was considered the optimal treatment for Zhuoliangyou 0985. It had a relatively large leaf area, a high number of grains per panicle, a large sink capacity, and a high available filled ratio of sink capacity, with a moderate grain-leaf ratio, which coordinated source-sink relationship and achieved the dual effects of fertilizer saving and yield increase.
To clarify the relationship between high-molecular-weight glutenin subunits (HMW-GS) composition and quality traits in newly developed wheat varieties (lines) in the Southern Huang-Huai Wheat Region, a total of 93 newly developed wheat varieties (lines) from this region were used as materials. The HMW-GS composition was identified using SDS-PAGE, and their distribution and quality characteristics were systematically analyzed in conjunction with grain quality traits. The results showed that nine subunit types were detected across the three Glu-1 loci, specifically, subunits 1 (72.04%) and Null (27.96%) at the Glu-A1 locus; subunits 7+9 (64.52%), 7+8 (30.11%), and 14+15 (5.38%) at the Glu-B1 locus; and subunits 2+12 (37.63%), 5+12 (32.26%), 5+10 (29.03%), and 2+10 (1.08%) at the Glu-D1 locus. Among the 15 identified subunit combinations, the most frequent combination was 1/7+9/2+12 (19.35%), while the frequency of the combination 1/7+8/5+10 was 8.60%. Based on quality traits, the tested materials were clustered into three groups, with Group I, Group II, and Group III accounting for 47.3%, 17.2%, and 35.5%, respectively. Group III exhibited the best performance across all quality indicators such as protein content, water absorption rate, and wet gluten content; the frequencies of subunits 14+15, 7+8, and 5+10 in group III were 6.06%, 36.36%, and 30.30%, respectively. Varieties (lines) carrying the pedigree of two founder parents, Yumai 2 and Zhou 8425B, accounted for 70.96% of the tested materials. Eight varieties such as Zhengmai 366, Xinmai 26, Jimai 44, and Fumai 916, were screened for carrying high-quality subunits and combinations. These results provide a theoretical basis for parent selection in wheat quality breeding in the Southern Huang-Huai Wheat Region and serve as an important reference for further optimizing HMW-GS composition and improving wheat quality.
In order to investigate the influence mechanism of pH level on the growth and development of rice and nutrient uptake under different nitrogen forms, rice cultivar Guanghui 751 was grown with five pH treatments (pH 3.5, 4.5, 5.5, 6.5, and 7.5) to study the effects on the biomass accumulation, root morphology, and nutrient uptake of rice under ammonium-nitrogen and nitrate-nitrogen conditions hydroponically. The results showed that under ammonium-nitrogen conditions, the highest rice biomass accumulation was found at pH 6.5 treatment; compared with the pH 3.5 treatment, the shoot and whole-plant biomass accumulation increased by 146.6% and 142.5%, respectively. Plant height and maximum root length increased significantly; total root length, root surface area, and root volume increased by 612.6%, 317.8%, and 147.1%, respectively. The uptake of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), copper (Cu), zinc (Zn), iron (Fe), and manganese (Mn) increased by 159.5%, 114.3%, 181.9%, 241.4%, 124.4%, 74.9%, 173.4%, 366.2%, and 3058.0%, respectively. Under nitrate-nitrogen conditions, the highest rice biomass accumulation was found at pH=4.5 treatment; compared with the pH=3.5 treatment, the shoot, root, and whole-plant biomass accumulation increased by 36.7%, 49.6%, and 38.6%, respectively. Plant height and maximum root length increased significantly; total root length, root surface area, and root volume increased by 129.9%, 83.0%, and 47.5%, respectively. The uptake of N, P, K, Ca, Mg, Cu, Zn, Fe, and Mn increased by 40.0%, 27.7%, 51.0%, 78.5%, 71.2%, 53.9%, 292.1%, 1449.5%, and 695.1%, respectively. In conclusion, the optimum pH values for rice under ammonium-nitrogen and nitrate-nitrogen conditions were 6.5 and 4.5, respectively. Under their respective optimum pH conditions, ammonium-nitrogen and nitrate-nitrogen primarily increased rice biomass accumulation by promoting root growth and development and increasing nutrient uptake.
Fertilizer management, especially the precise application of panicle fertilizer, has a significant impact on rice yield, quality, and nitrogen use efficiency (NUE). To determine a reasonable panicle fertilizer ratio and application leaf-age stage for the rice-growing region along the Yellow River in Henan Province, this study used rice variety Bianjing 5 as the experimental material. At a nitrogen application rate of 277.5 kg/ha, the effects of two nitrogen fertilizer management modes—the conventional mode (with panicle fertilizer applied at the 2nd and 1st leaf stages from the top) and the precise delayed mode (with panicle fertilizer applied at the 4th and 3rd leaf stages from the top)—combined with silicon and zinc fertilizer on the yield, grain quality, and NUE of japonica rice were investigated. The results showed that both the precise delayed nitrogen mode and the application of silicon and zinc fertilizers had significant yield-increasing effects, with increments ranging from 3.9% to 13.2%. The precise delayed nitrogen mode improved yield by increasing the effective panicle number, improving the panicle-forming rate and grain number per panicle, while silicon and zinc supplementation improved yield by increasing grain number per panicle and 1000-grain weight. The precise delayed nitrogen mode combined with silicon and zinc application significantly increased the milled rice rate and head rice rate, reduced the chalky grain rate and chalkiness, and effectively improved the appearance and processing quality of the rice. Furthermore, the precise delayed nitrogen mode significantly improved nitrogen uptake efficiency, physiological nitrogen efficiency, nitrogen agronomic efficiency, and nitrogen partial productivity, while silicon and zinc application significantly enhanced nitrogen agronomic efficiency and nitrogen partial factor productivity. In conclusion, the precise delayed nitrogen mode combined with silicon and zinc fertilization contributes to the construction of a healthy population of japonica rice in the rice-growing region along the Yellow River in Henan Province, achieving synergistic improvement in yield, grain quality, and nitrogen use efficiency.
The whiteness (WI) of wheat flour and its products is a key indicator influencing the commercial quality of wheat. Using 94 wheat varieties as experimental materials, the differences in flour WI and its products among different varieties and their influencing factors were investigated. The results showed significant differences in WI among wheat varieties, while the correlation analysis of flour and fresh noodle sheet color from the same material showed the same performance. Flour WI was highly significantly negatively correlated with grain hardness, grain protein content, wet gluten content, dough development time, and stability time; significantly negatively correlated with trough viscosity, final viscosity, and setback value; and positively correlated with gluten index, breakdown, and pasting temperature. Grain hardness, grain protein content, sedimentation value, pasting temperature, and breakdown accounted for 80.9% of the variation in flour WI. Gluten index, sedimentation value, pasting temperature, and breakdown had significant positive effects on flour WI, while grain protein content and grain hardness exerted significant negative effects. The negative correlation between flour WI and hardness was the strongest (r = -0.83), indicating that hardness is the key factor affecting wheat WI and color. The WI and color of flour and fresh noodle sheets from soft wheat were generally higher than those from hard wheat. The distribution frequencies of variation loci of quality-related genes, namely Pinb-D1b, Pina-D1b, Ppo-A1b, Ppo-D1a, TaPod-A1b, Lox-B1a, Psy-A1b, Psy-B1a/b, Psy-D1a, TaPds-B1b, TaZds-A1a, and TaLyc-B1b, were 54.7%, 2.2%, 21.3%, 3.9%, 8.0%, 0.0%, 0.0%, 98.9%, 96.6%, 78.5%, 5.3%, and 53.8%, respectively. Thirteen high-WI soft wheat varieties, such as Yangmai 15, Yangmai 25, Chuanmai 93, Mianmai 902, and Yangmai 45, and high-WI hard wheat varieties, such as Zhoumai 36, Huaimai 33, Yangfumai 15, and Ningmaizi 218, were screened. The WI of high-WI soft wheat varieties was higher than that of hard wheat, and the ratio of superior color gene allelic variations in these varieties was higher than that of the overall materials. By strengthening the utilization of elite parents while emphasizing the pyramiding of superior color genes and the screening of related phenotypes, the WI and color of wheat varieties can be gradually improved.