Cowpea wilt is a soil-borne fungal disease caused by Fusarium oxysporum f.sp. tracheiphilum (FOT), and is one of the most important diseases of cowpea. In our study, several biocontrol bacteria were isolated and evaluated. One of the bacteria which were found the best antagonistic effect to FOT was identified and studied on its antagonistic mechanism and growth promoting function, while it was evaluated by the control and growth-promoting effects. This study established the foundation for the research and development of excellent biocontrol agents for cowpea Fusarium wilt. 93 strains of bacteria were isolated by plate dilution method, and 11 biocontrol strains, which exhibited good inhibitory effect on the pathogenic bacteria of cowpea wilt, were screened by plate confrontation method, and the antagonistic strain SD13 had the best inhibition rate (the inhibition rate reached 82.0%). SD13 was identified as Bacillus velezensis based on Morphology and 16S rDNA sequence. Liquid medium co-culture method showed that SD13 could break down the cell wall of the hyphae, spores, and germinated spores of the FOT. Assay medium test results indicated that SD13 could secrete cellulase, protease and β-1,3-glucanase, and had the function related to the production of siderophore, nitrogen fixation and solubilise inorganic phosphorus. Plate confrontation method showed that SD13 had antagonistic activity against a wide spectrum of pathogenic fungi, with inhibition rate ranging from 66.7% to 82.3%. Pot experiments indicated that in four treatments in concentration of 10⁴, 10⁶, 10⁸, 10⁹ CFU/mL, there were the best control effect of SD13 in concentration of 10⁶ CFU/mL, reaching 62.0%, and the growth promotion effect was the second, lower than that of the concentration of 10⁸ CFU/mL. This study shows that SD13 has good biocontrol and growth-promoting effects, and is preliminarily clarified the antagonistic mechanism and functions related to growth-promoting ability, which has potential application value for the prevention and control of Fusarium wilt.

Cymbidium eburneum and Cymbidium insigne are species endemic to Hainan exclusively and belong to the endangered species. 23 F₁ hybrid progenies from C. eburneum and C. insigne were used to accurately verify hybrids, to clarify the genetic relationships between hybrid progenies and the parents with SSR molecular markers. Eight pairs of primers were screened out from 48 pairs of primers using PCR, and 23 hybrid progenies were confirmed to be true hybrids, with the true rate of hybrid progenies100%. 23 hybrids populations identified by primers Cym45, Hub131 and Hub8 had both parental specific loci. 23 hybrid populations identified by primers Hub125 had only father specific loci, Cym9 had a new specific loci. Primer Cym25, Hub125 and Cym47 were low polymorphi [polymorphism information content (PIC)<0.25], primer Cym45, Hub131, Hub8 and Cym9 were middle-highly polymorphi (0.25<PIC<0.5). The PIC of primer Cym172 was 0.59, indicating that it was highly polymorphi, and could be used as the preferred primer for fingerprint construction of the progenies of C. eburneum × C. insigne. UPGMA cluster analysis results showed that when the genetic coefficient was 0.8111, the studied germplasms could be divided into three categories. Among which the parents constituted two categories, and the hybrid population belonged to the third. The hybrid population could be divided into three clusters, X₇ was a clade, X₆ and X₂₁ were clustered together, and the other 20 F₁ hybrid population s were the third. This study showed that SSR molecular markers could be used in hybrid identification and genetic diversity analysis of orchids species endemic to Hainan, which could provide an effective foundation and data base for orchid breeding and new species selection in Hainan. At the same time, the PIC of SSR molecular markers was an important indicator reflecting the ability of molecular markers. The middle-highly polymorphic primers and highly polymorphic primers developed in this study could lay a foundation for the construction of Hainan wild orchid gene atlas and the establishment and development of Hainan wild orchid germplasm bank.

In this study, four stabilizers including potassium hydroxide (KOH), ammonia, sodium dodecyl sulfate (SDS) and potassium laurate were added to concentrated natural rubber latex (CNRL). The performance of the CNRL film was most affected by the amount of KOH. With the increase of KOH content, the Mooney viscosity of the film increased and the shrinkage rate decreased. The tensile strength, tensile stress, elongation at break, tear strength and hardness all decreased rapidly. With the increase dosage of potassium laurate, the Mooney viscosity and the shrinkage rate of the raw rubber film decreased to a certain extent. The tensile strength had a tendency to increase first and then decrease. With the increase of ammonia consumption, there was also a trend of first rising and then falling. More dosage of sodium dodecyl sulfate (SDS) would lead to lower tear strength of the raw rubber film. The performance of the vulcanizate film was also most affected by the amount of KOH. With the increase of KOH dosage, the M_L and M_H of the vulcanizate film would increase. The t₁₀, t₅₀ and t₉₀ would be shortened, and the film shrinkage was reduced. In addition, the tensile strength and elongation at break of the rubber film decreased. The tensile stress and tear strength had a trend of increasing first and then decreasing. As the amount of ammonia increased, the t₉₀ of the vulcanizate film would increase. The shrinkage rate of the film increasesd, and the tensile stress first increased and then decreased. With the increase of the amount of SDS, the t₉₀ of the vulcanizate film would be prolonged and the film shrinkage was reduced. With the increase of potassium laurate dosage, the M_L and M_H of the vulcanizate film would increase, the film shrinkage was reduced, and the tear strength showed a trend of increasing first and then decreasing. It could be seen from the hardness change that the film would become soft after adding KOH and the hardness would be greatly reduced. The Mooney viscosity of the film was greatly improved. After the addition of potassium laurate, the Mooney viscosity of the film decreased significantly, but the hardness of the film did not change much. From the perspective of vulcanization, after adding KOH, the vulcanization degree of the rubber film increased, and the vulcanization time decreased. KOH had a certain promotion and promotion effect on the vulcanization degree of the film. However, combined with the mechanical properties of the vulcanized film. The tensile stress of the film increased after adding KOH, but the tensile strength, tear strength and elongation were significantly reduced. However, the film strength changed little when the other three stabilizers were added.

Vertical greening is a technology that uses a new substrate to plant plants on the structure facade and vertical surface, which has been widely used in various urban scenarios. The performance of vertical greening substrate has fundamental research significance for three-dimensional greening cultivation. The effect of water and fertilizer maintenance effect of the substrate is the key factor to determine whether the vertical greening planting plants can survive and grow well. Curing soilless matrix is a cultivation material processed by artificial waste. It has the advantages of clean hygiene, stable nature and good cultivation performance. It is an ideal material for vertical greening cultivation. Retention effect of water and fertilizer is the key factor to determine whether survival and growth of plants in vertical greening, this study was based on the three types of solidified soil-free substrates, which are currently commonly used in vertical greening, including the soilless substrate 'Lei Tu', the Japan solid soilless substrate 'Pafcal' and the domestic solid soilless substrate 'Tan Mian'. Peat soil was selected as the control. The physical and chemical properties, retention of water and fertility were compared, and the potted experiment was executed to verify the effect on cuttage and griwth of plants. The 'Lei Tu' bulk density was small and the water holding capacity was strong, which had advantages over the other two substrates, but the air permeability of the three substrates was poor, so it needed to keep the plant gap in the planting process. The pH value of the 'Lei Tu' and the 'Pafcal' was more suitable for plant growth. The organic matter content and nitrogen content of the three substrates were higher than the natural soil. The concentration of nitrogen and phosphate loss of the three substrates in soluble experiments was extremely low, which would hardly cause the water body to be nutritious and affect the environment. The results of the three types of matrix solidification had reached experimental expectations, which had a significant advantage over peat, the traditional substrates. The effects of cuttings and growth of Callisia repens 'Pink Lady' of the 'Lei Tu' were the best and were the most ideal vertical greening substrate among the three tested substrates. The results would provide the theory of the cultivation of vertical greening.

The drying characteristics of Docynia delavayi at different temperatures (40, 60, 80 and 100 ℃) were investigated and a kinetic model was established to clarify the hot air drying characteristics and appropriate drying temperature for D. delavayi and to achieve its quality control in the hot air drying process. The effect of different drying temperatures on the dried product quality in terms of color, rehydration ratio (RR), the contents of active ingredients (polyphenols, flavonoids, polysaccharides) and antioxidant capacities were evaluated. The moisture ratio curve of D. delavayi decayed exponentially during the drying process, and the drying rate curve was divided into three stages, acceleration, constant rate and decreasing rate. With the increase of drying temperature, the moisture diffusion of D. delavayi intensified, and the drying rate increased obviously, the effective diffusion coefficient of water (D_eff) and activation energy (E_a) was 0.61×10^-6-1.78×10^-6 m²/s and 17.64 kJ/mol, respectively. The data analysis revealed that the Page model fitted well, with the coefficient of determination (R²) all above 0.98, and X², SSE in the range of 0.149×10^-3-0.548×10^-3 and 0.184×10^-2-0.493×10^-2, respectively, which could better reflect the variation pattern of D. delavayi according to moisture ratio with drying temperature during the hot air drying process. The quality of the D. delavayi exhibited some differences under different drying temperatures. D. delavayi dried at 40 ℃ had good rehydration that at 60 ℃ could maintain the maximum color, and possess the highest total polyphenols, total flavonoids, total polysaccharides content and better antioxidant capacities. The results of the post-drying quality analysis showed that temperature had a significant effect on the quality of D. delavayi, and 60 ℃ was better for the retention of color and active substances content. Correlation analysis showed that there was a correlation between color, rehydration ratio (RR), active substances content and antioxidant capacities of D. delavayi, while the active substances content was negatively correlated with the total color difference value (ΔE) and positively correlated with the rehydration ratio (RR) and antioxidant capacities. In addition, it also confirmed that the antioxidant capacities of D. delavayi were the combined effect results of multiple active substances. In conclusion, the quality of D. delavayi dried at the optimal temperature of 60 ℃ was more outstanding. The present study would provide an experimental basis for the further development and utilization of D. delavayi.

The problem of heavy metal pollution of crops occurs frequently, and heavy metal pollution has become one of the important factors affecting crop quality. By applying 0.75, 1.50 and 3.00 g/kg potassium sulfate into soil under cadmium (Cd) stress, the effects of potassium fertilizer on the physical and chemical properties of rhizosphere soil and cadmium accumulation in plants of Ilex asprella were studied. This study is expected to lay a foundation for the development of cadmium excess reduction technology in Ilex asprella. The result shows that, the application of high amount of potassium sulfate fertilizer could reduce the soil pH by 1.72% to 8.09%. Cadmium stress can reduce the content of soil organic matter, and the application of medium (1.50 g/kg) and high (3.00 g/kg) amount of potassium sulfate can increase the content of soil organic matter, total potassium and available potassium. In addition, the application of potassium sulfate generally increased the content of biologically available cadmium in the soil, only on the 30th day after the application of low concentration of potassium sulfate (0.75 g/kg), the content of bioavailable cadmium in the soil decreased by 1.94% compared with the Cd treatment group. Under cadmium stress, the application of potassium sulfate could increase the SOD activity in leaves of Ilex asprella, and then enhance the tolerance to cadmium stress. Low could increase the SOD activity in leaves of Ilex asprella, and then enhance the tolerance to cadmium stress. Low concentration of potassium sulfate (0.75 g/kg) inhibited the transport of cadmium from rhizome to leaf and effectively reduce the accumulation of cadmium in the root and stem of Ilex asprella. To sum up, the application of high amount of potassium fertilizer decreased the soil pH, and the application of medium (1.50 g/kg) and high (3.00 g/kg) amount of potassium sulfate could increase the content of soil organic matter, total potassium and available potassium, thus improved soil fertility. The results also showed that low concentration of potassium sulfate could reduce the content of bioavailable cadmium in soil, inhibit the transport of cadmium from roots and stems to leaves, and reduce the accumulation of cadmium in roots and stems of Ilex asprella.

Sugarcane plantations are mainly distributed in mountainous areas with high land fragmentation and complex cropping structure in Yunnan Province. Frequent cloud cover reduces the good observations of the land cover by using optical remote sensing. So it is difficult to extract sugarcane plantations with a high accuracy based on satellite optical remote sensing data. Xinping Country, a typical mountainous sugarcane plantation region, was chosen to explore a suitable method for the extraction of sugarcane plantations in mountainous areas. In this study, Landsat-8 and Sentinel-2 optical imagery for Xinping from October 1, 2019 to July 1, 2021 were used as the main data sources, and the DEM data and field survey data were used as the auxiliary data. The synthetic time-series images with high spatial-temporal resolution were constructed on Google Earth Engine (GEE). Firstly, we analyzed the differences among sugarcane and evergreen vegetation, water body, impervious, and other crops in spectral index characteristics, phenological characteristics, and topographic characteristics. Secondly, we determined the optimal thresholds for extracting sugarcane plantations for the four phenological parameters including rise time, fall time, above integral of season and below integral of season, as well as elevation and slope factors based on the training samples. Thirdly, we mapped the sugarcane plantations of 2020 and the mapping accuracy was verified using the validation samples in the study area. Finally, the spatial distribution of sugarcane plantations was analyzed at town scale. The results showed that synthetic time-series images based on the Landsat-8 and Sentinel-2 optical imagery could increase the number of good observations in the study area and improve the spatial resolution of the images, which could solve the problem of low quality of remote sensing images in mountainous areas and could better monitor phenological characteristics and seasonal changes of vegetation. The resultant 2020 sugarcane map had overall, user and producer accuracy of 97.07%, 88.85% and 80.57%, respectively with the Kappa coefficient of 0.83. According to the annual sugarcane map in 2020, there was a total of 7705 hm² sugarcane in Xinping, there were more sugarcane distribution in the southeast than in the northwest, as well as the southeast terrain was lower than that in the northwest. There were significant differences in the area of sugarcane plantations between townships, the township with the largest sugarcane plantation area is Mosha Town (2786 hm²) and the township with the smallest sugarcane plantation area is Gucheng district (0.87 hm²), which is consistent with the actual research. The sensitivity analysis of phenology parameters for sugarcane mapping demonstrated that the four parameters including rise time, fall time, above integral of season, and below integral of season are all important to improve the user accuracy and reduce the commission errors in the sugarcane mapping. The sugarcane plantation mapping algorithm proposed in this study could provide a reference for the extraction of sugarcane plantations in the complex landscapes of mountainous areas in the future.

Dendrobium is the general name of all plants in Genus Dendrobium Sw. It is an important flower resource in orchid plants and has high ornamental and medicinal value. Crossbreeding is the main method to cultivate new varieties of Dendrobium, However, the breeding period of Dendrobium is long, and the whole breeding cycle usually takes several years. The identification of germplasm resources is the basis of breeding work. This study of the identification of the hybrid progeny lines of Dendrobium is expected to provide molecular basis for early selection of hybrid progeny and rapid identification of new varieties (lines), shorten the breeding cycle and accelerate the progress of Dendrobium breeding. As a new type of molecular marker, iPBS marker does not need to obtain the LTR sequence in advance. Compared with other molecular markers, it has the advantages of simplicity, efficiency and wide application. In the study, the authenticity of 19 hybrid F₁ lines of Dendrobium Pittero Gold 'Diamond Ring' × Dendrobium Btilliant Smile 'Hiromi' was identified by iPBS molecular marker technology, and perform genetic diversity and cluster analysis. Seven primers with clear amplification bands, high polymorphism and good repeatability were selected from 83 iPBS primers for the authenticity identification of hybrid progenies of Dendrobium. A total of 69 bands were amplified by the seven primers, of which 51 were polymorphic, and the polymorphic ratio was 73.91%. The 19 F₁ hybrid lines tested could amplify paternal characteristic bands and were identified as true hybrids. A large number of paternal characteristic bands were amplified in the offspring plants, indicating that more genetic information of Dendrobium Pittero Gold 'Diamond Ring' was introduced into the offspring individuals, showing obvious paternal inheritance. Cluster analysis showed that the vast majority of the hybrid offspring tended to be paternal first and then maternal. The results of genetic similarity coefficient analysis showed that the average genetic similarity coefficient between the hybrid offspring and the male parent was greater than that of the female parent, indicating that the tested hybrid offspring were more inclined to the male parent in heredity, which was consistent with the clustering results. The variation of genetic similarity coefficient between the two parents and the offspring was small, indicating that the genetic diversity between the offspring of the hybrid combination was not rich. This is not conducive to the emergence of heterosis varieties, in the subsequent experiments, plants with large genetic differences should be selected for hybrid breeding in order to obtain heterosis varieties. The results showed that the iPBS molecular marker technology could be used as an effective method for the screening and identification of early hybrids in Dendrobium cross breeding. The results of this study would provide a scientific basis for further revealing the genetic diversity between parents and progeny of Dendrobium population.

The phenotypic characters of sugarcane germplasm resources native of domestic were analyzed to study the law of genetic variation, so as to provide a theoretical basis for the selection of sugarcane genetic breeding parents and the construction of core germplasm population. 160 sugarcane varieties/parents from 8 different regions native of domestic were used as materials to evaluate the phenotypic traits with reference to the specification and data standard for sugarcane germplasm resources description. Most traits showed rich genetic diversity. Among them, the diversity index of the 20 quality traits was 0.07-1.40, with a mean of 0.84, which was the highest in bud type and the lowest in stalk shape. Five quantitative traits had 8.74%-38.26% of the coefficient of variation, with a mean of 17.69%, which was the highest in millable stalks (38.26%) and the smallest in stalk lengt (8.74%). The diversity index (H′) of the five traits was 1.46-1.83, with a mean of 1.64, which was the highest in stalk lengt (1.83) and the lowest in millable stalks (1.46). The average coefficient of variation of the tested materials in different regions was 13.56%-22.33%. The coefficient of variation of the variety population from Hainan was the largest (22.33%), and the dispersion of quantitative characters was the largest. The coefficient of variation of variety population from Fujian was the lowest (13.56%). By cluster analysis,160 accessions materials were divided into seven categories based on four traits, among them class 5 accounted for 90.62% of the total germplasm resources. This group resource has the characteristics of high yield and sugar content. The results could provide an important reference for the utilization of sugarcane germplasm resources, parental selection and variety breeding.

Leaf color mutants are not only an ideal material for the study of rice functional genomics, but also of great significance for hybrid rice breeding. They can also be used as ornamental rice, committed to building rural leisure agricultural sightseeing spots and promoting rural revitalization. Based on a rice bright green leaf mutant bgl-2 obtained by radiation mutagenesis in the early stage of our research group, this study compared the difference in leaf color between the mutant bgl-2 and the wild-type SIPI, and showed that the mutant bgl-2 showed a bright green color different from the wild-type SIPI. The content of photosynthetic pigments in leaves was determined by 95% ethanol extraction at tillering stage. The results showed that the chlorophyll content of mutant bgl-2 was not significantly different from that of wild-type SIPI. By observing the other plant morphology of mutant bgl-2, it was found that the leaf tips of its flag leaf and the last two leaves were bent, and the flag leaf was significantly shorter than that of wild-type SIPI, and its plant height was also significantly shorter than that of wild-type SIPI. It was found that the 1000 grain weight, grain length and grain width of mutant bgl-2 was significantly smaller than those of wild-type SIPI, but its length width ratio was not significantly different from that of wild-type SIPI. The structure of flag leaf cells of wild-type SIPI and mutant bgl-2 at tillering stage was observed by the transmission electron microscope. The results showed that the cell wall of mutant bgl-2 was significantly thickened, but the thickness of outer membrane of cell membrane was significantly reduced, the inner membrane was almost degraded, and the lamellar structure of thylakoid in chloroplast ultrastructure was looser than that of wild-type SIPI. F₁ plants were obtained by hybridization with mutant bgl-2 as female parent and wild-type SIPI as male parent. The investigation found that its leaves were normal green, and the morphology of flag leaf and inverted two leaves were normal, while the F₂ population after self pollination isolated normal green leaf seedlings and bright green leaf seedlings with obvious leaf color differences. The segregation ratio of normal leaf color plants and bright green leaf plants in the population was counted, which showed that it conformed to the single gene model of 3 : 1. The above results clarify the phenotype and genetic characteristics of the mutant bgl-2, and provide a theoretical basis for the study of the molecular regulation mechanism of the mutant bgl-2 and promoting its application in rice breeding. The location cloning and functional analysis of BLG-2 gene will be carried out later.