In order to investigate the adaptability of quinoa in Jiaodong Peninsula and determine the suitable sowing period, 7 sowing periods were set for 'Qingli No. 1' in this experiment, and agronomic traits, yield and quality traits were evaluated. The results showed as follows. The plant height of quinoa treated in 7 sowing dates ranged from 163.50 to 172.08 cm, stem diameter from 19.59 mm to 26.07 mm, effective branching rate ranged from 39.81% to 55.91%, main spike length ranged from 46.08 cm to 54.75 cm, and the above indexes decreased significantly with the delay of sowing dates. The grain yield, 1000-grain weight and grain diameter decreased significantly with the delay of sowing date. The highest yield was 4432.56 kg/hm2, and the highest 1000-grain weight was 2.94 g. In early sowing (March 12), the crude protein, crude fat and starch contents were 14.44%, 7.27% and 63.62%, which were significantly higher than those of late sowing. The results showed that the high yield and high quality of quinoa could be achieved by proper early sowing (mid-March) under the warm and humid climate at low altitude in Jiaodong Peninsula.
To prevent and control the spread of potato cyst nematode, a research on field control methods for this pest was carried out. In the experiment, dazomet fumigation and fosthiazate hole application were adopted. The effects of these measures on potato production were analyzed through various indicators, such as the SPAD value and nitrogen content of the leaves, plant height, plant weight, yield at maturity, and the number of potato cyst nematodes at the pre-sowing, flowering, and maturity stages of the potatoes, and the control effect of potato cyst nematode. The results revealed that both of the treatments significantly improved the plant height and enhanced photosynthesis of leaves. At the same time, the control measures reduced the infection of potato roots by cyst nematode. The average control efficacy of dazomet fumigation for potato new cysts nematode was 91.07%, which was significantly higher than that of fosthiazate hole application and control treatment. Compared with the control, dazomet fumigation and fosthiazate hole application increased the average yield by 20.13% and 9.69%, respectively. Dazomet fumigation was notably more effective in suppressing the potato’s infection of potato cyst nematode than fosthiazate hole application, and it also substantially increased the rate of big tuber and potato yield.
Sulfuric acid digestion is an effective method to decompose cellulose, hemicellulose and lignin into monosaccharides or disaccharides. The experiment was designed as a 3-factor completely randomized experimental design with response surface method was used to investigate the effects of sulfuric acid mass fraction, acid digestion temperature and acid digestion time on the content of fulvic acid using rapeseed cake as the raw material for acid digestion, and to screen the optimal parameters for the preparation of fulvic acid from rapeseed cake. The results showed that the mass fraction of sulfuric acid, acid digestion temperature and acid digestion time had significant effects on the content of xanthohumic acid. The optimal parameters for the preparation of fulvic acid from rapeseed cake by sulfuric acid digestion were the temperature of 100℃, sulfuric acid mass fraction of 25% and acid digestion time of 0.5 h. The content of fulvic acid prepared from rapeseed cake by sulfuric acid digestion was the highest in this condition, which was 14.17%, nitrogen content was 0.56%, phosphorus content was 0.25% and potassium content was 0.0028%.
To clarify the interaction effects of planting density and N-fertilization rate of summer maize, the maize varieties ‘DH605’ and ‘MY73’ were used as experimental materials, 2 densities (67500 plants/hm2, 82500 plants/hm2 ) and 2 N-fertilization rate (210 kg/hm2, 300 kg/hm2) were set to analyze the effects of density and N-fertilization on summer maize yield. The results showed that as the density increased, the effective number of ears increased, and yield increased by 18.0%, while the number of grains per spike and the number of grains per row decreased significantly; increasing N-fertilization rate could reduce the adverse effects of densification on maize plant yield and ear traits. The yield increased by 6.0%, the kernels per ear increased by 2.6%, and the leaf area per plant increased by 6.4%. Density and N-fertilization rate mainly affected the kernels per ear. ‘MY73’ had higher yield, better ear characteristics and leaf area under high-density and high N-fertilization rate conditions. It was found that the adverse effects of maize plant and population competition after increasing planting density could be regulated by appropriate increase of nitrogen fertilizer. Therefore, when the planting density of the two varieties increased to 82500 plants/hm2, the N-fertilization rate of 300 kg/hm2 was more likely to achieve high yield. The study is expected to provide some technical support for the synergistic improvement of summer maize quality and yield in western Henan.
In order to explore the morphological characteristics and germination characteristics of Rhododendron species, the morphological structures of seeds from eight species were observed using a stereo microscope (LIOO SZ745). We also explored the impacts of gibberellin (GA3) concentration, GA3 treatment time, and soaking time in water on the germination traits of Rhododendron species. Additionally, we conducted a comparative analysis of germination traits among different species and provenances of Rhododendron species, as well as the impact of seed size on germination. The results showed that: (1) the seeds of the Rhododendronspecies were spindle-shaped, oval and small, the longitudinal and the aspect ratio of R. micranthum seeds was significantly higher than the other three Rhododendron seeds, the transverse diameter of the R. molle seeds was significantly higher than the other three Rhododendron seeds (P<0.01). (2) R. micranthum had the highest germination rate at GA3 0 mg/L, 4 h in the processing time, and the soaking time of 24 h; R. simsii seed was the highest in germination rate at GA3 100 mg/L, the processing time was 12 h, and the soaking time was 48 h; when the GA3 400 mg/L, the processing time was 4 h, the soaking time was 24 h, the germination rate of the R. mucronulatum was the highest; when the GA3 0 mg/L, the processing time was 4 h, the soaking time was 48 h, the germination rate of R. molle was the highest. (3) There were differences in germination rate, germination potential, germination lag, germination peak, germination duration and germination index of Rhododendron seeds among different provenances. R. simsii had the highest germination rate and germination potential, R. mucronulatum had the longest germination lag, germination peak and germination duration, and R. molle had the largest germination index. (4) The longitudinal diameter, transverse diameter and aspect ratio of Rhododendron seeds were negatively correlated with germination rate, germination potential, germination time lag, germination peak period, germination duration and germination index. This study can provide a theoretical basis for species identification and introduction and propagation of Rhododendron plants.
In order to summarize the research practice of tea tree breeding in Guizhou since the 11th Five-Year Plan, based on relevant literature on tea economy, technological achievements, talent cultivation, discipline construction, and variety resource research, this paper systematically summarizes the main research and development activities and landmark achievements of tea tree breeding in Guizhou from the perspectives of industrial technology economy and technological history. The results showed that Guizhou had conducted a series of studies on the diversity, functional genes and genomics, physiological characteristics, reproductive technology, variety adaptability, and wild tea tree protection of tea tree resources. 15 tea tree varieties have obtained the right of new plant variety protection, 2 varieties have passed provincial approval, and 4 varieties have been registered as national non major crop varieties. One invention patent was obtained, and one provincial standard was formulated and issued. It won 2 provincial second prizes and 2 provincial and ministerial third prizes. The paper provides excellent seed source guarantee for the high-quality development of the tea industry in the province, and lays the foundation for further research on tea tree breeding in the future.
To investigate the effects of different parents in interspecific hybridization of the genus Fraxinus on hybrid F1 seeds, a total of 36 interspecific hybridization combinations of the genus Fraxinus were designed, and F1 seeds from various hybrid combinations were collected. Statistical analysis of characteristic data such as thousand seed weight, wing length, wing width, and wing length/width of seeds was conducted. SPSS 24.0 software was used to perform variance analysis on the data, comparing the differences between inter species hybrids and intra species hybrids, as well as the effects of different genotypes of maternal and paternal parents on hybrid species. The results showed that there were significant differences in the four indicators of F1 seeds between interspecific hybridization and intraspecific hybridization when F. pennsylvanica was used as the maternal parent and different species of Fraxinus male parent. The variation range between different combinations of interspecific hybridization was large. However, when using F. velutina as the maternal parent and different species of Fraxinus male parent, there was no significant overall difference in seed traits between interspecific hybridization and intraspecific hybridization. Four genotypes of F. velutina were hybridized with the female parent of F. mandshurica, resulting in significant variations in seed traits in the F1 generation. Five genotypes of F. velutina were hybridized with the male parent of F. pennsylvanica, resulting in significant differences in thousand seed weight traits in the F1 generation; The F1 seed trait variation obtained by crossing the male parent of F. mandshurica with and the female parent of F. velutina was superior to that of the hybrid combination with F. pennsylvanica as the female parent. The results showed that the F1 hybrid seeds in the interspecific hybrid of the genus Fraxinus had abundant genetic variation. Overall, it is believed that the variation of hybrid seeds with F. velutina as the maternal parent is higher than that as the paternal parent. Different genotypes of F. mandshurica as the paternal parent have no significant effect on the seed traits of F1 generation. The study provides a reference for the selection of parents for interspecific hybridization in the genus Fraxinus, further improving the efficiency of Fraxinus.
In response to the pressing challenges of land resource scarcity, climate change, and environmental pollution, this study designs an AIoT-based smart soilless cultivation system that integrates soilless cultivation with modern information technology. The system aims to overcome the limitations of traditional agriculture and promote the development of agricultural automation, intelligence, and precision management. This system incorporates Internet of Things (IoT) sensing, computer vision, big data analytics, and machine learning technologies. It employs multi-source heterogeneous data fusion to analyze crop growth conditions, utilizes artificial intelligence algorithms for intelligent greenhouse environment regulation, and enables remote visual monitoring through web and mobile interfaces. The entire system is highly integrated in terms of hardware and software on the Jetson nano platform, offering excellent parallel computing capabilities and scalability. Experimental results demonstrate that, compared to the manually managed control group, vegetables under the intelligent regulation exhibited a 15.4% shorter growth cycle, a 17.0% increase in plant height, a 26.7% increase in leaf count, and a 27.4% improvement in plant weight. Additionally, the remote control interface proved to be convenient and efficient, validating the system's outstanding performance in promoting the modernization of soilless agricultural cultivation. This system provides robust technical support for the development of precision agriculture and has the potential to drive modern agriculture towards sustainable, efficient, and environmentally friendly development.
In this paper, the evolution characteristics (spatiotemporal distribution, persistence, intensity, etc.) of summer high temperature days and heat waves in the middle of Hexi Corridor were studied, and the effects on the growth and yield components of maize during the critical period were analyzed, providing theoretical foundations for the development of early warning of high temperature events, risk prediction, maize flowering and yield forecasting services in the region. Based on daily maximum air temperature data from June to August at meteorological stations in the middle of Hexi Corridor from 1961 to 2023, linear trend, Mann-Kendall test and other methods were used to reveal the frequency, process, intensity characteristics and evolution of high temperature weather, and to analyze the effects on the growth traits and yield components such as 100-seed weight of maize, the local dominant crop. The results indicated that high temperature weather in the middle of Hexi Corridor mainly occurred in the desert oasis from late July to early August. An abrupt change of high temperature weather took place in the late 1990s. About the number of (hazardous) high temperature days and heat waves, big interannual changes, massive occurrences in a short time and an upward trend were discovered. There was a significant negative correlation between the number of high temperature days and the spike period. The intervals between tasseling and silking stages in years with more high temperature days were equal or shorter than the climatological normal. In years with more high temperature days in the jointing-booting stage, the tasseling-silking stages were simultaneous or delayed compared to climatological normals. The number of high temperature days during and after the flowering stage was significantly negatively correlated with 100-seed weight (R=-0.8495). For every additional day, the 100-seed weight decreased by 1.345 grams. Finally, it is proposed to establish an intelligent agricultural monitoring network to predict disasters, carry out experiments on high temperature meteorological applicable technologies and screen high temperature resistant varieties to cope with high temperature risk, so as to ensure high quality and high yield of maize.
To clarify the comparative advantage characteristics of corn planting regions in Yunnan Province, based on the corn planting region and yield data of 16 prefectures and cities in Yunnan Province from 2000 to 2020, production scale index, production concentration index, scale comparative advantage index, efficiency comparative advantage index, and comprehensive comparative advantage index were used to calculate and analyze. The results showed that: (1) the corn planting regions in Yunnan Province were concentrated in the northeast and south, especially in Qujing, Zhaotong, and Wenshan. (2) Qujing, Zhaotong, Wenshan, Pu'er, and Lincang had contributed the most to the total corn planting area in the province, which concentrated more than half of the total maize planting area in the province. (3) Qujing, Zhaotong, Wenshan, Dali, and Honghe had contributed the most to the province's corn yield, accounting for more than half of the total corn yield in the province. (4) The comparative advantage of corn production scale in Yunnan Province was generally on the rise, while the comparative advantage of corn production efficiency and comprehensive comparative advantage were generally stable. The comprehensive advantageous production regions had been formed in the northeast regions such as Zhaotong and Qujing, the southeast regions such as Wenshan, and the southwest regions such as Lincang, and the northwest regions such as Nujiang and Diqing. The scale comparative advantage accelerated the continuous enhancement of the polarization effect of comprehensive comparative advantage. In order to accelerate the high-quality development of the corn industry in Yunnan Province, it is necessary to continuously ensure policy support for advantageous corn planting regions, gradually tap into the production potential of corn planting comparative advantages, and appropriately reduce the proportion of corn in non advantageous corn planting regions.
The study of rural energy in China is of great value for comprehensively promoting the realization of the strategy of rural revitalization. Through the CiteSpace visual metrology software, this paper conducted a scientific econometric analysis of the CSSCI source journals and the core source journals of Peking University in China's rural energy research from 1992 to 2023, analyzed the research status, hot spots, research themes and development trends of rural energy problems in a visual way, and drew relevant conclusions. The research overview shows that the overall literature volume in rural energy research shows a trend of ‘slow growth-rapid increase-gradual decrease-increase again’. The compound impact factor of the top journals is high, indicating that the research field of rural energy in China has high academic value and influential achievements. Secondly, from the perspective of research hotspots and themes, the research on related energy issues mainly includes four types of themes, namely: the study of the evaluation indicators of rural energy problems, the problem of rural energy poverty in the context of rural revitalization, the influencing factors of rural energy consumption, and the impact of rural energy policies. The development process of research is divided into two stages, the stage of ‘germination and emergence’ and the stage of ‘exploration and development’. Future research can expand the research content and methods from the macro and micro perspectives of individuals and society, or the spatio-temporal dynamic differences between regions, pay attention to the problems of rural energy poverty and clean energy, and provide a scientific basis for policy practice.
