The worldwide climate changes every year due to global warming, waterlogging, drought, salinity, pests, and pathogens, impedes crop productivity. Brassica napus is one of the most important oil crops in the world, and rapeseed oil is considered one of the most health-beneficial edible vegetable oils. Recently, miRNAs have been found and confirmed to control the expression of targets under disruptive environmental conditions. The mechanism is through the formation of the silencing complex that mediates post-transcriptional gene silencing, which pairs the target mRNA and target cleavage and/or translation inhibition. However, the functional role of miRNAs and targets in B. napus is still not clarified. This review focuses on the current knowledge of miRNAs concerning development regulation and biotic and abiotic stress responses in B. napus. Moreover, more strategies for miRNA manipulation in plants are discussed, along with future perspectives, and the enormous amount of transcriptome data available provides cues for miRNA functions in B. napus. Finally, the construction of the miRNA regulatory network can lead to the significant development of climate change-tolerant B. napus through miRNA manipulation.

Rice–crayfish rotation expanded rapidly in China, as it provides considerable profit and reduces pesticide application. This study investigated the impact of different mechanical transplanting methods and planting geometry on the yield and lodging resistance of an indica rice variety under a rice–crayfish rotation system in 2018 and 2019 in Hongze Lake district, using an excellent-quality variety Taoyouxiangzhan. Seedlings were mechanically transplanted using two mechanically transplanted carpet seedling (MTCS) with equal spacing (30 cm) at five spacings and mechanically transplanted pot seedling (MTPS) with wide and narrow rows (23 cm + 33 cm) at five spacings. The yield of MTPS was 8.3% higher across 2 years under the most optimum density than MTCS using the same density, mainly due to a significantly increased number of spikelets per panicle. Accompanied by the decrease in planting density, rice yield first increased and then decreased under each mechanically transplanting method, and reached the maximum in the A4 and B4 treatments (63.9 × 10⁴ seedlings ha⁻¹), respectively. Compared with MTCS, MTPS significantly increased the fresh weight of single stem, plant height, gravity center height, ear weight, length and area of the upper three leaves, so as to increase the bending moment at basal internodes by whole plant (WP), while it also increased the stem diameter, wall thickness and stem and leaf sheath dry weight per unit length of the second internode at the base, resulting in a significant increase in the force applied to break the base segment (F) and the bending moment of whole plant (M). The higher increase percentage in M than WP led to a decreased lodging index. The lodging index of both mechanically transplanting methods reduced with declined planting density in virtue of the improved breaking load of the basal internode, and it was primarily a result of increased stem diameter, wall thickness and plumpness of basal internode. The balance between the high yield and lodging resistance of Taoyouxiangzhan under a rice–crayfish rotation system can be realized at 63.9 × 10⁴ seedlings ha⁻¹, with MTCS at 15.7 cm plant spacing and MTPS at 16.8 cm. Generally, MTPS showed obvious advantages in yield and lodging resistance than MTCS.

Remote sensing has been used as an important means of monitoring crop growth, especially for the monitoring of the formation of crop yield in the middle and late growth period. The information acquisition on the yield formation period of winter wheat is of great significance for winter wheat growth monitoring, yield estimation and scientific management. Hence, the main goal of this study was to verify the possibility of monitoring the grain-filling process of winter wheat and its in-field variability using an alternative non-destructive method based on orbital remote sensing. High-resolution satellite imageries (3 m) were obtained from the PlanetScope platform for three commercial winter wheat fields in Jiangsu Province, China during the reproductive stage of the winter wheat (185–215/193–223/194–224 days after sowing (DAS)). Based on the quantitative analysis of vegetation indices (VIs) obtained from high-resolution satellite imageries and three indicators of the winter wheat grain-filling process, linear, polynomial and logistic growth models were used to establish the relationship between VIs and the three indicators. The research showed a high Pearson correlation (p < 0.001) between winter wheat maturity and most VIs. In the overall model, the remote sensing inversion of the dry thousand-grain weight has the highest accuracy and its R² reaches more than 0.8, which is followed by fresh thousand-grain weight and water content, the accuracies of which are also considerable. The results indicated a great potential to use high-resolution satellite imageries to monitor winter wheat maturity variability in fields and subfields. In addition, the proposed method contributes to monitoring the dynamic spatio-temporality of the grain-filling progression, allowing for more accurate management strategies in regard to winter wheat.

The rice–crayfish continuous production system developed rapidly due to its high economic benefits and eco-friendly nature in China. This study explored the effects of mechanically transplanted methods and planting geometry on the relationship between rice yield and canopy structure, under rice-crayfish rotation using excellent-quality indica rice, and carried out in 2018 and 2019. Three mechanical transplantation methods were set as follows: carpet seedlings mechanically transplanted with 30 cm equal row spacing (CMTE), pot seedlings mechanically transplanted with narrow row spacing with alternating 23 cm/33 cm wide row spacing (PMTWN), and equal row spacing at 28 cm (PMTE). Different plant spacings (CMTE1-CMTE6, PMTWN1-PMTWN6, PMTE3, and PMTE4) were set in accordance with different mechanical transplanting methods. CMTE and PMTWN both included six transplanting densities, while PMTE included 2 transplanting densities. Results showed that rice yield was improved by 2.87–6.59% under PMTWN when compared to CMTE, which was mainly due to the increase in spikelets per panicle and filled-grain percentage. Dry matter accumulation was increased and larger leaf area indexes were observed under PMTWN than CMTE at the rice main growth stage. Yield of CMTE and PMTWN treatments increased at first and then declined with decreased planting density. Under suitable planting density, PMTWN could optimize rice population structure and increase rice yield compared with PMTE. For tested rice variety, pot seedlings were mechanically transplanted alternating alternating 23 cm/33 cm wide row spacing, combined with a plant spacing of 16.8 cm, was proper for its yield improvement under rice-crayfish rotation.