Indica-japonica hybrid rice cultivars show great yield potential but poor eating quality and require more nitrogen (N) input relative to japonica rice. However, the effect of N levels on the eating quality of indica-japonica hybrid rice is little known. A field experiment was carried out to investigate the effects of four N levels on two indica-japonica hybrid rice cultivars (Yongyou12 and Yongyou17) differing in eating quality. The results showed that the contents of amylose chains and water-insoluble storage proteins, especially prolamin, increased largely under a high N level, leading to deterioration of the rice-eating quality, although a low N level (100 N kg/ha) had a less negative effect on the eating quality. Moreover, both of the indica-japonica hybrids had high ratios of inferior grains (IG), and the ratio of IG increased with the N level. Grain weight and the immature ratio of IG were reduced and increased with the N level, respectively, which are also factors for deterioration of the eating quality. The two cultivars differed greatly in the responses of eating quality to the N level, with Yongyou17 being more sensitive than Yongyou12. The current results indicated that a high N level deteriorates the eating quality of indica-japonica hybrid rice mainly due to a large increase of IG.

In Brassica napus, hypocotyl elongation under shade conditions poses a significant challenge in intensive agricultural systems, particularly in rice-rapeseed rotation regimes where straw mulching reduces light quality. However, the genetic basis of light-mediated hypocotyl growth responses in B. napus remains poorly understood. In this study, hypocotyl lengths were measured in a panel of 267 diverse rapeseed accessions under five light conditions including white, red, far-red, blue light, and complete darkness. Substantial phenotypic variation was observed among accessions and treatments, with red light exhibiting the weakest inhibitory effect on elongation, and white light showing the strongest suppression. Genome-wide association studies (GWAS) (−log₁₀ (p) > 4.5) identified numerous significant SNPs associated with light response, highlighting candidate genes such as KAN1, ILL2, VQ18, HDA15, and HAT3 involved in photomorphogenesis and hormonal signaling pathways. These findings elucidate the polygenic control of light responsiveness in B. napus and provide molecular targets for breeding shade-tolerant varieties to enhance crop resilience under dense planting and straw mulching systems.