Legume rhizodeposition promotes nitrogen fixation by soil microbiota under crop diversification.

Biological nitrogen fixation by free-living bacteria and rhizobial symbiosis with legumes plays a key role in sustainable crop production. Here, we study how different crop combinations influence the interaction between peanut plants and their rhizosphere microbiota via metabolite deposition and functional responses of free-living and symbiotic nitrogen-fixing bacteria. Based on a long-term (8 year) diversified cropping field experiment, we find that peanut co-cultured with maize and oilseed rape lead to specific changes in peanut rhizosphere metabolite profiles and bacterial functions and nodulation. Flavonoids and coumarins accumulate due to the activation of phenylpropanoid biosynthesis pathways in peanuts. These changes enhance the growth and nitrogen fixation activity of free-living bacterial isolates, and root nodulation by symbiotic Bradyrhizobium isolates. Peanut plant root metabolites interact with Bradyrhizobium isolates contributing to initiate nodulation. Our findings demonstrate that tailored intercropping could be used to improve soil nitrogen availability through changes in the rhizosphere microbiome and its functions.

Analysis of Biomechanical Parameters of Martial Arts Routine Athletes' Jumping Difficulty Based on Image Recognition.

This paper uses image segmentation technology to examine the biomechanical parameters of martial arts routine athletes' whirlwind legs and backflips, two difficult jumping sports. The successful completion of the whirlwind leg, a typical martial arts jumping difficulty, during the buffer period of the take-off stage, the left knee angle flexion, the drop of the body's center of gravity, and the drop of the horizontal speed of the center of gravity are all significantly correlated, so it is only necessary to grasp airborne altitude and speed from landing. The 720-degree cyclone foot has a flying height of 0.470.11 m, which is 4 cm higher than the 540-degree cyclone foot (0.430.11 m). The antigravity of the last foot is greater than about 1.3 kgf/kg of the left foot during the run-up stage, which allows for a higher rotational angular velocity and completion of the 720-degree difficulty of the whirlwind foot. As a result, it is crucial to pay attention to how you step with your right foot. In the backflip, the coordination of the two legs and the upper body is crucial. The right foot's effective braking can help to increase the body's rising angle. The trunk inclination angle in the flying stage is between 110° and 120°, the knee angle is between 60° and 70°, and the angle between the two legs is between 35° and 35°. When lifting off the ground and landing, the tibialis anterior muscle discharge is greater than the gastrocnemius muscle discharge, which helps to maintain the balance between the fulcrums. As a result, it is necessary to let the non-supporting leg fall first in order to achieve the goal of a smooth landing.