Lily (Lilium spp.) has elegant flowers and beautiful colors, which makes it popular among people. However, the poor stress resistance and self-propagation ability of lily limit its application in landscaping to a great extent. In addition, transgenic technology is an important means to improve plant characteristics, but the lack of a stable and efficient genetic transformation system is still an important factor restricting the development of lily transgenic technology. Therefore, this study established a good lily regeneration system by screening different explants and plant growth regulators of different concentrations. Then, the genetic transformation system of lily was optimized by screening the critical concentration of antibiotics, the concentration of bacterial solution, and the infection time. Finally, the homologous lily cold resistance gene LlNAC2 and bulblet generation gene LaKNOX1 were successfully transferred to ‘Siberia’ and ‘Sorbonne’ to obtain lily transgenic lines. The results showed that when the stem axis was used as explant in ‘Siberia’, the induction rate was as high as 87%. The induction rate of ‘Sorbonne’ was as high as 91.7% when the filaments were used as explants. At the same time, in the optimized genetic transformation system, the transformation rate of ‘Siberia’ and ‘Sorbonne’ was up to 60%. In conclusion, this study provides the theoretical basis and technical support for improving the resistance and reproductive ability of Oriental lily and the molecular breeding of lily.

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This paper analyzed the clustering degree and spatial distribution characteristics of the imported timber landing processing industry in China’s Heilongjiang province based on the survey and statistical data during 2019–2021. The location entropy method was used to quantify the clustering degree of timber landing processing. Multi-distance spatial clustering analysis, hotspot analysis, and spatial autocorrection analysis were conducted to identify the spatial pattern of enterprises and analyze the hotspots and spatial correlation among the prefecture-level cities in the region. Results showed that there was obvious industrial agglomeration in imported timber landing processing in Heilongjiang Province, and the overall spatial pattern of the industry showed significant spatial aggregation at different spatial scales. The hotspots were primarily concentrated in the southeast of the province with a high level of industrial development, while the cold spots were primarily in the western and northern parts with a low level of industrial development. The distribution of the imported timber landing processing industry at the provincial level was positively correlated, but not very significantly. There was large spatial heterogeneity for the imported timber landing processing industry. Some suggestions were put forward in order to accelerate the construction of imported timber landing processing industrial clusters in the region.

This paper considers the procurement mechanism with two supply channels, namely, an option contract purchase and a spot market. For the mechanism, under the stochastic demand and the stochastic spot price, we consider the portfolio procurement with the spot trading liquidity and the option speculation respectively. To maximize the buyer’s profit, we establish two optimal portfolio procurement strategy models for those two scenarios. Based on the buyer’s cost-benefit analysis, we present a solution method to each model and provide an optimal ordering policy to the buyer. By the obtained results, we analyze the role of the spot trading liquidity and option speculation in a buyer’s expected profit. Some numerical experiments are presented to show the validity of the formulated models.

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