Apart from directly affecting the growth and development of crops, Cd in the soil can easily enter the human body through the food chain and pose a threat to human health. Therefore, understanding the toxicity of Cd to specific crops and the molecular mechanisms of their response to Cd is essential. In this study, hydroponic experiments were utilized to study the response of foxtail millet to Cd stress through phenotypic investigation, enzyme activity determination, ultrastructure, ionome, transcriptome and metabolome. With the increase in cadmium concentration, both the growth and photosynthetic capacity of foxtail millet seedlings are severely inhibited. The ultrastructure of cells is damaged, cells are deformed, chloroplasts swell and disappear, and cell walls thicken. Cd stress affects the absorption, transport, and redistribution of beneficial metal ions in the seedlings. Multi-omics analysis reveals the crucial roles of glycolysis, glutathione metabolism and phenylpropanoid and lignin biosynthesis pathways in Cd detoxification via energy metabolism, the antioxidant system and cell wall changes. Finally, a schematic diagram of foxtail millet in response to Cd stress was we preliminarily drew. This work provides a basic framework for further revealing the molecular mechanism of Cd tolerance in foxtail millet.

The use of various sustainable materials and cement is a frequent and successful strategy for stabilizing problematic soil. The current research discusses the potential use of discarded millet husk ash (MHA) and cement (C) as subgrade ingredients to improve the geotechnical qualities of soil (S). MHA and cement are mixed in different proportions and the engineering characteristics of the stabilized soil are studied. The study involves examining fundamental properties, such as specific gravity and Atterberg's limits, as well as engineering properties, including Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR) tests. These evaluations are conducted to assess the feasibility of using the MHA-cement blend as a construction material. Additionally, FTIR & SEM analysis shows the addition of MHA-cement blend effectively couples with the soil. The test findings demonstrate that adding MHA to soil lead to decreased liquid limits and plasticity indices. The maximum dry density (MDD) was observed to decrease when MHA was mixed with soil. When 8% cement was incorporated to the S:MHA (84.5:7.5) combination, the UCS value rose even higher reaching 1600.1 kPa. The S:MHA:C arrangement in the ratio of 84.5:7.5:8 had the greatest California bearing ratio (CBR). Fourier transform infrared spectroscopy (FTIR) elucidated the various types of bond formations present within the soil composite and deeper peaks depicted greater presence of cementitious compounds after curing period. SEM analysis exhibited a greater density of N-A-S-H and C-A-S-H gels in comparison to natural soil samples. The findings suggest that the MHA-cement blend can effectively enhance the geotechnical properties of problematic soils, while addressing issues of agricultural waste management. This research contributes to several Sustainable Development Goals (SDGs), including SDG 9 (Industry, Innovation, and Infrastructure) by promoting innovative construction materials.

To solve the problem of large sowing amount and poor sowing uniformity for millet, according to the physical characteristics of the millet seed and its sowing agronomic requirements, an electromagnetic vibration type fine and small-amount seeder was designed, and the main technical parameters of the seeder were determined, in order to realize the functions of furrow opening, electronically controlled seed metering, soil covering and pressing. Based on the principle of electromagnetic vibration, an electromagnetic vibration type seed metering device was designed to achieve uniform seeding of the millet seed with a small sowing amount; a seeding amount electronic control device was designed using an STM32 microcontroller, which realized the switching to sowing agronomic mode and the adjustment of the seeding amount with sowing operation speed; a vibration experimental bench was set up to simulate the vibration state of field operation, and studies on the seeding performance and vibration damping of the seed metering device by the isolation spring were carried out, as well as field sowing tests for verification. When the working voltage of the seed metering device is 80-160 V, the coefficients of variation for seeding uniformity per row and for total seeding uniformity are not greater than 3.57% and 2.39%, respectively, and the seed damage rate is less than 0.5%. The installation of isolation springs can increase the maximum vibration acceleration of the seed metering device by 10.61-28.20%, significantly reducing the impact of external vibrations on the seed metering device. Within the range of suitable sowing operation speeds, the electronic control device can meet the seeding amounts along with sowing operation speed in the 6, 7.5 and 9 kg/hm2 sowing agronomic modes, and the coefficient of variation for seeding uniformity per row, for total seeding uniformity and for sowing uniformity are not greater than 4.63%, 2.48% and 23.38%, respectively. This study provides a reference for the development of sowing machinery for millet crop.

Optimizing canopy spacing configuration can enhance resources utilization, supporting robust growth and dry matter production, while mitigating the risk of lodging and improving crop yield and quality. However, research specifically addressing optimal canopy spacing configurations for foxtail millet remains limited. Over a two-year period, a field experiment in the North China Plain assessed the impacts of four-row spacing configurations (T0: 40 + 40 cm; T1: 30 + 50 cm; T2: 20 + 60 cm; T3: 10 + 70 cm), to investigate the effects of row spacing configuration on lodging resistance, canopy spatial configuration, stem characteristics, yield, and water productivity (WP) of foxtail millet, aiming to elucidate the underlying regulatory mechanisms. Row spacing configurations significantly influenced lodging resistance, yield, and WP. Under T1, improvements were observed in stem morphology and mechanical properties, particularly in the 2nd-6th basal internodes (I2-I6). The light interception rate in T1 at wide rows in the middle canopy (30-90 cm aboveground) increased by 97.89 %, compared to T0. Partial least squares-structural equation modeling revealed that improved light interception in wide rows in the middle canopy contributed to a rise in diameter and dry plumpness of I2. This, in turn, promoted greater breaking resistance of I2 and tensile resistance, ultimately reducing the lodging likelihood. Simultaneously, the decrease in lodging resulted in higher yield and WP at yield level of foxtail millet. Therefore, T1 demonstrated the lowest lodging rate (67.34 %-91.92 % lower than T0), and the highest yield and WP at yield level (4.10 %-8.03 % and 20.79 %-22.46 % higher than T0). Optimizing canopy spacing configuration is essential for cultivating high-yielding and water-efficient foxtail millet populations. The results indicated that the 30 + 50 cm row spacing configuration improves light distribution in the middle canopy, enhancing lodging resistance and consequently increasing both yield and WP. This research offers a theoretical foundation for foxtail millet breeding and agronomic practices to achieve lower lodging rate, higher yields, and enhanced WP in the North China Plain.