Cotton is one of the world’s important cash crops and occupies a significant position in agricultural production and the national economy. However, insect pests severely affect the growth, yield and quality of cotton. To ensure high and stable cotton yields, the cultivation of insect-resistant transgenic cotton via transgenic technology can not only effectively reduce the impact of chemical pesticides on crops but also exert excellent control effects against pests such as cotton bollworms. In this study, the plant expression vector pC2300-VEC harboring the target genes epsps, cry1Ac and vip3A was introduced into the genome of the recipient cotton cultivar CCRI 24 via Agrobacterium-mediated transformation. The obtained transgenic cotton plants were subjected to the identification of target genes and target traits, and the insect-resistant transgenic cotton line BrsC35 was ultimately obtained. PacBio sequencing combined with conventional molecular characterization methods was used to analyze its insertion site, copy number and other characteristics, providing a new germplasm for insect-resistant transgenic cotton.

Alfalfa (Medicago sativa L.) is a vital global forage crop. Transgenic technology promises enhanced yield and quality, but requires rigorous environmental risk assessment, particularly regarding pollen-mediated gene flow, for which standardized protocols are lacking. Based on an optimized in vitro culture medium, this study developed a method to assess alfalfa pollen viability. Using a single-factor experimental design, key assessment parameters were established at 1/4/8 h and 20/30/40 °C. A comparative analysis revealed no significant difference (p > 0.05) in pollen viability between the transgenic line SA6-8 and its non-transgenic parent “ZM-1” within this evaluation system. This result indicates that the genetic modification did not impact the pollen viability of SA6-8. By establishing this in vitro germination-based pollen viability assessment system and comparatively analyzing pollen viability between transgenic alfalfa and its non-transgenic parent under diverse environmental conditions, our approach provides crucial insights for optimizing transgenic alfalfa planting strategies and strengthening biosafety review protocols.

Rice (Oryza sativa L.) is a vital staple crop, and the environmental risk assessment of transgenic varieties is crucial for formulating biosafety policies. Rice pollen grains are spherical, with an average diameter of 40.03 ± 2.75 μm. This study established a standardized protocol for in vitro pollen germination by first optimizing key culture conditions. A single-factor experimental design identified the optimal medium composition as 150 g/L sucrose, 40 mg/L boric acid, 20 mg/L calcium chloride, 10 mg/L monopotassium phosphate, and 10 mg/L magnesium sulfate. The ideal germination temperature was determined to be 31 ± 1 °C, with no germination observed below 16 °C or above 40 °C. Pollen germination rates declined significantly within 5 min post-isolation and ceased completely after 30 min. Building on this optimized protocol, a standardized evaluation method was developed, defining key assessment conditions at temperatures of 25/31/37 °C and post-isolation times of 0/5/15 min. Under these defined conditions, the pollen viability of glyphosate-resistant transgenic rice G2-6 was compared to its non-transgenic recipient ZH11. No significant differences were found at any tested time–temperature combination (p > 0.05). This work establishes a practical and reproducible standard for transgenic rice pollen assessment, offering a scientific basis for evidence-based biosafety regulation and policy-making.