Effects of Intercropping Patterns on Cadmium Tolerance of Perilla Frutescens and Soybean

In this study, we intercropped hyperaccumulator Perilla frutescens with soybean to explore the effects of intercropping under cadmium stress based on the physiological growth indexes of plant, cadmium absorption capacity, and soil cadmium forms Experiments showed that compared with mono-cropping, intercropping soybean’s biomass, catalase (CAT) activity, peroxidase (POD) activity, total chlorophyll and net photosynthetic rate were significantly increased by 1042%~10658%, 1578%~7381%, 1345%~2337%, 376%~1500% and 7121%~31278%, while P frutescens’s significantly decreased by 9387%~9507%, 1562%~2572%, 12056%~15331%, 715%~756% and 3056%~5076% Under 5 and 10 mg kg-1 Cd treatments, the Cd content in roots, stems, leaves, pods and grains of intercropping soybean decreased significantly by 1072%~3174%, 1488%~2168%, 1995%~3413%, 2222%~5270% and 791%~1786% along with enrichment coefficient decreasing by 1486%~2787%, while those of P frutescens significantly increased by 8700%~2141%, 948%~2155%, 2305%~3766% and 1818%~9412% along with enrichment coefficient significantly increasing by 2000%~7775% Additionally, citric acid, succinic acid, oxalic acid and tartaric acid worked importantly in heavy metal detoxification in plants Strikingly, the content of soil exchangeable Cd (EXC) under intercropping was the highest, even higher than that of mono-cropping soybean and P frutescens, which accounted for 37%~42% under the same stress condition Therefore, intercropping Perilla frutescens with soybean provide a potential strategy for Cd phytoremediation

Effects of Mixed Application of Wood Vinegar and Biochar on Cadmium Absorption of Pakchoi under Different Concentrations of Cadmium Stress

Because of its characteristics, wood vinegar is widely used in agricultural production processes. Wood vinegar can be used as a strong antioxidant, anti-bacteria, plant growth agent, an insecticide, and currently shows superiority in the treatment of heavy metals. Wood vinegar contains organic acids, organic compounds, and phenol, which can effectively adsorb heavy metals. A large number of studies have been conducted on the adsorption of heavy metals by biochar, but few studies have analyzed the effects of biochar and wood vinegar fertilization on the growth of cadmium soil genus plants and changes in soil heavy metal forms. This article analyzed the effects of wood vinegar and biochar mixed fertilizer on the growth and plant efficacy of pakchoi from the properties of wood vinegar, and confirmed that 0.75% wood vinegar liquid treatment is the most effective concentration. By analyzing the effectiveness of 0.75% wood vinegar and biochar mixture and single fertilization, the combined application of biochar + wood vinegar reduced the absorption rate of cadmium by pakchoi leaves and roots by 12.8% and 13.1% compared with the single treatment group. The yield of crops increased by 111.9~150.1%. The results of evaluating the enrichment coefficient and single-factor index are 0.17~0.67%, 0.005-0.008, and the ranking is D> E> C> B> A> CK. When observing the changes in soil morphology, the content of residual cadmium, carbonate-bound cadmium, and iron-manganese oxide-bound cadmium increased by 0.3~233.7 times, and the exchangeable cadmium content and the content of organic and sulfide-bound cadmium were reduced to 1.0~6.6 times. It can be seen that under different cadmium stress conditions, the mixed fertilization of wood vinegar and biochar will reduce the growth of pakchoi and the plant availability of cadmium, and it has a higher mitigation effect on cadmium soil pollution.

Resequencing of 1,143 indica rice accessions reveals important genetic variations and different heterosis patterns

Obtaining genetic variation information from indica rice hybrid parents and identification of loci associated with heterosis are important for hybrid rice breeding. Here, we resequence 1,143 indica accessions mostly selected from the parents of superior hybrid rice cultivars of China, identify genetic variations, and perform kinship analysis. We find different hybrid rice crossing patterns between 3- and 2-line superior hybrid lines. By calculating frequencies of parental variation differences (FPVDs), a more direct approach for studying rice heterosis, we identify loci that are linked to heterosis, which include 98 in superior 3-line hybrids and 36 in superior 2-line hybrids. As a proof of concept, we find two accessions harboring a deletion in OsNramp5, a previously reported gene functioning in cadmium absorption, which can be used to mitigate rice grain cadmium levels through hybrid breeding. Resource of indica rice genetic variation reported in this study will be valuable to geneticists and breeders.