# The Analysis of the Applications of Crop Seed Tape Sowing Technology and Equipment: A Review
## 3 Research on Key Technology and Equipment for Seed Tape Manufacture
### Materials Used for Seed Tape  
The material of seed tape is one of the important factors affecting crop growth. Originally, people used paper or common plastic as a carrier to make seed tapes [31]. People gradually preferred a kind of soluble paper to make seed tape according to [PERSON]'s research [5]. With the continuous breakthrough of material technology, the selection of seed tape materials presents a trend of diversification. Researchers have done a lot of work to explore the suitable materials for seed tape. Scientists realized that seed tapes should have good toughness without affecting seed germination. Therefore, the material used to make the agricultural plastic film is a good choice to produce seed tape. However, the extensive use of agricultural plastic film causes great pollution to the environment [32; 33; 34; 35]. To reduce the pollution caused by agricultural plastic films to farmland, [PERSON] et al. [36] recycles agricultural plastic by catalytic cracking. While recovering seed tape materials is a complex and tedious process. Therefore, the seed tape material should also be biodegradable.  
The degradation of agricultural plastic film could be accelerated by adding starch-containing biodegradable plasticizers to it [37]. The biodegradable materials used for seed tape production mainly include two types; one is biodegradable cellulose fibre material and the other is biodegradable synthetic cellulose material [38]. Polylactic acid fibre (PLA) which belongs to biodegradable synthetic cellulose material is widely used in agricultural film production as an environmentally friendly material [39]. Its final degradation products are carbon dioxide and water. This is consistent with the water-soluble membrane proposed by some researchers [40]. In order to improve the properties of seed tape materials and select suitable seed tape materials, researchers have done a lot of work. Table 2 summarized the basic research on improving the property of seed tape material. To determine suitable seed tape material, [PERSON] [27] selected four materials (absorbent cotton non-woven fabric, kraft paper, PP non-woven fabric and PLA non-woven fabric) for a series of tests which includes composition analysis, spectral analysis, tensile strength analysis, degradation rate and seedling emergence rate analysis. The results showed that the degradation rate of absorbent cotton non-woven fabric was the fastest but the tensile strength was lower. The emergence rate of kraft seed tape was the lowest. The degradation rate of PP non-woven fabric was the slowest. After a comprehensive comparison, [PERSON] believes that PLA non-woven fabric was more suitable as seed tape material. Due to the wide variety of crop seeds, the effects of seed tape materials, production techniques and other factors on the growth of different crops are unclear. [PERSON] [41] studied 12 species and batches of seeds with a total of 6200 seeds under different seed tape treatments through a series of experiments which were divided into 3 phases (Figure 1). The results showed that a tissue paper material used by Seed Developments Limited produces maximum seedling penetration rates and the penetration rates of seedlings were greater in 2 ply format seed tapes than 4 ply format seed tapes of the same material. [PERSON] and [PERSON] [42] used sea pandan leaves as the main material for seed tape making, and then carried out the experiment of seed tape cultivation for the choy sum planting, which provided a theoretical basis for the selection of seed tape materials.