In order to assess the breeding value of HoCP series sugarcane germplasms introduced from USA, 12 HoCP sugarcane clones (HoCP00-1142, HoCP01-517, HoCP01-564, HoCP02-610, HoCP02-623, HoCP03-704, HoCP03-708, HoCP03-716, HoCP05-902, HoCP07-613, HoCP07-617 and HoCP92-648) were used as core parents in 73 sugarcane cross combinations. The effect on combining ability, economic breeding values of height, diameter, effective stem number, sugar content and cane yield for the 11 HoCP sugarcane parents and 73 F₁ population were estimated using the family test method. Significant differences were found for height among HoCP males and cross combinations, whereas no significant differences were detected for height among HoCP females, suggesting that the plant height was affected by only male and cross combination. For the stem diameter, effective stem number, sugar content and cane yield, there were significant differences existed among different HoCP female, male and cross combination, indicating that the four characters were affected by female, male and cross combination. Among the 12 clones, the highest general combining ability for height, diameter, effective stem number, sugar content and cane yield appeared in HoCP03-704, HoCP02-623, HoCP02-610, HoCP07-617, and HoCP92-648 as female, respectively, while HoCP03-704, HoCP02-623, HoCP07-617, HoCP03-708 and HoCP02-623 as male possessed the highest general combining ability for height, diameter, effective stem number, sugar content and cane yield, respectively. The better economy breeding value (EBV) and general combining ability (GCA) in cane yield and sugar content were detected in HoCP02-623, HoCP03-708 and HoCP92-648 as the female, and HoCP01-517and HoCP07-617 as the male, which indicated that the clones could be used as excellent female and male with high-yield and hight-sugar, respectively. Among the 73 cross combinations, the highest special combining ability for height, diameter, effective stem number, sugar content and cane yield appeared in HoCP03-704×'Neijiang 03-218', 'Yuetang 00-236'×HoCP00-1142, 'Yacheng 07-71'×HoCP05-902, 'Yuetang 00-236'×HoCP03-708, HoCP01-564×'Guitang 92-66', respectively. A total of 38 cross combinations showed possitive EBV. The combinations 'Yuetang 94-128'×HoCP01-517, HoCP01-564×'Guitang 92-66', 'Guitang 02-467'×HoCP01-564 had better special combining ability in cane yield, sugar content and EBV than the others, which could be considered as the most important productive families in future breeding program. However, HoCP03-716×'Funong 02-6404', 'Yuetang 99-66'×HoCP01-564 and 'Yuenong 73-204'×HoCP01-564 showed lower special combining ability in five characters and lower EBV than other combinations, suggesting that the combinations did not suit for using as productive families in future breeding program. Therefore, the results would provide helpful information for using HoCP sugarcane parents in cross combination.

Low temperature is an important factor limiting the growth, development and yield of pitaya. 2,4-Epibrassinolide (EBR) can enhance the resistance of plants to various stresses such as low temperature. In order to improve the cold resistance of pitaya and alleviate the damage caused by low temperature, the cutting seedlings of red pulp pitaya 'Taiwan No. 6' was sprayed with 0.5 mg/L EBR, and treated under low temperature stress (4℃/0℃, 12 h/12 h) for 7 days. Reactive oxygen species (ROS) content, antioxidant enzyme activity, relative conductivity (REC), malondialdehyde (MDA) content, fatty acid composition and content were determined to clarify the regulatory effect of EBR on the cold tolerance of pitaya seedlings. Furthermore, the relationship between antioxidant system and fatty acid unsaturation of membrane lipids under low temperature stress was studied. Low temperature stress (4℃/0℃, 12 h/12 h) increased the content of reactive oxygen species (ROS), significantly decreased the content of unsaturated fatty acids. The fatty acids unsaturation (UFA/SFA) and double bond index (DBI) reduced by 32.1% and 32.4% respectively, and significantly increased the content of malondialdehyde (MDA) and relative conductivity (REC), resulting in decreased membrane stability and increased membrane permeability. The plants showed obvious watery stains and slight wilting, and the index of chilling injury reached 0.60. Under low temperature, exogenous EBR treatment increased the activities of superoxide dismutase, peroxidase and catalase, effectively removed the excessive accumulated ROS, significantly reduced the production rate of superoxide anion and the content of hydrogen peroxide, alleviated the oxidation reaction between ROS and unsaturated fatty acids in membrane lipids, and increased the relative content of unsaturated fatty acids in pitaya seedlings. The proportion of saturated fatty acids decreased significantly, UFA/SFA and DBI increased significantly, EBR maintained the stability of cell membrane, reduced REC and the content of membrane lipid peroxidation products MDA, greatly reduced watery stains of plants, and the index of chilling injury was reduced to 0.25. It is becouse EBR can activate the antioxidant enzyme system and effectively remove a large number of accumulated ROS under stress, leading to reduce the double-bond fracture of unsaturated fatty acids in membrane lipids, alleviate the degree of membrane lipid peroxidation, maintain the stability and function of membrane membrane. In conclusion, under low temperature stress, exogenous EBR can effectively improve the cold tolerance of pitaya seedlings. Its mechanism is by increasing the activity of antioxidant enzymes in pitaya seedlings, remove excess accumulated ROS, and significantly increase the unsaturation of cell membrane fatty acids, so as to reduce the degree of membrane lipid peroxidation and electrolyte leakage, maintain the stability and function of cell membranes.

With the rapid development of the livestock industry, the demand for forage is increasing, and it is urgent to screen new forage crop varieties. In this study, two national forage sugarcane varieties were used as the control. The biological yield of 15 sugarcane varieties and the routine nutritional components of 10 green fodder were measured and analyzed to explore the principal component variation of sugarcane at different cutting stages, and evaluate the feeding value of sugarcane, so as to provide scientific basis for more than one year of sugarcane harvest and whole plant feeding. Crude protein (CP), acid detergent fiber (ADF), water-soluble carbohydrate (WSC) and crude fat (EE) were selected by factor principal component analysis, which basically contained all the information of the indexes measured. Among the 15 sugarcane varieties, 'Yunzhe 12-201' had the highest CP content, which was 8.80 %, 'ROC22' with the lowest ADF content, 35.25 %. The highest WSC content was from 'Yunzhe 00-290', 6.16 %. The highest EE content was from 'Yunzhe 01-286', 1.40 %. The CP content of 'ROC22' and 'Yunzhe 12-201' was higher than that of CK1 and CK2. The ADF content of 'Q27','ROC22','Yunzhe 01-286', 'Yunzhe 06-160','Yunzhe 12-142-1-J', 'Dianzhe 11-728' was lower than that of CK1 and CK2. The WSC content of 'Q27', 'Yunzhe 00-290', 'Yunzhe 12-142-1-J', 'Yunzhe 16-16', 'Dianzhe 11-726' and 'Dianzhe 11-728' was higher than that of CK1 and CK2. There was no significant difference in EE content between 15 sugarcane varieties and CK1 (P>0.05), except 'Yunzhe 06-160'. There was no significant difference in EE content between 14 sugarcane varieties and CK2. Except for 'Dianzhe 11-726', there was no significant difference in Ca content between 14 varieties and CK1 and CK2. The CP content of all sugarcane varieties in the first cutting period was higher than that in the second cutting period, and the ADF, WSC, EE and Ca content in the first cutting period was higher than that in the second cutting period, with 12, 5, 4 and 14 sugarcane varieties, respectively. The total yield of 15 sugarcane was 71.40-163.95 t/hm², higher than that of CK1 and CK2. The yield of CP, ADF, WSC and EE per unit area of 15 sugarcane varieties exceeded that of CK1 and CK2, and the Ca yield of 15 sugarcane varieties exceeded that of CK2. Comprehensive evaluation showed that sugarcane could be used as ruminant feed with high nutritional value and economic benefit. In this study, five varieties 'Q27', 'ROC22', 'Yunzhe 01-286', 'Yunzhe 12-201', 'Dianzhe 11-728' were selected as the sources of forage sugarcane, which could not only meet the raw material needs of forage animals, but also form an industrial development model of sugar-animal linkage..

The effects of phosphorus (P) and lime application on yield and biomass and P uptake and utilization of sweet corn were evaluated with a field experiment. Research on the appropriate rate of P application would provide a theoretical basis in improving sweet corn yield and P use efficiency. The field experiment was a split-plot design with main-plot randomly assigned into each of four blocks. The main-plot treatments were four P application rates (0, 60, 120 and 180 kg/hm², expressed as P₀, P₆₀, P₁₂₀ and P₁₈₀). The split-plot factors were two lime levels (0 and 750 kg/hm², expressed as L₀ and L₁). The responses of sweet corn yield, P uptake, soil available P and P fertilizer utilization efficiency to P fertilizer application and lime application were studied. The yield of sweet corn increased significantly under P₁20 and P₁₈₀ treatments without lime by 19.4% and 18.5%, respectively, compared with P₀ treatment. Compared to P₀, the yield of sweet corn increased significantly by 14.0% under P₆₀ treatment with lime. Under P₆₀ treatment, lime increased the yield of sweet corn significantly by 12.7%. P fertilizer application increased both total biomass and P uptake of sweet corn significantly. After two sweet corn growing seasons, soil available P under P₆₀ treatment had no significant difference comparing with the original value. Soil available P basically maintained a balance under P₆₀ treatment. Soil available P in P₁₂₀ and P₁₈₀ treatments increased by 103.8% and 228.4%, respectively, compared with the original value, and soil available P increased obviously in 0-20 cm soil layer. The fresh ear yield per P uptake and P physiological efficiency decreased significantly with P application rates. Also, the P use efficiency of sweet corn declined with P application rates. P agronomic efficiency, recovery efficiency, and partial factor productivity increased significantly under lime treatments with P₆₀ treatment, compared with no-lime treatments. Together, these results indicated that the application of 60 kg/hm² P fertilizer combined with lime can be an efficient way to obtain high yield and P utilization efficiency of sweet corn and maintain the balance of soil available P.

Harvested cucumber is sensitive to low temperature, which is subjected to chilling injury during cold storage and causes heavy postharvest losses. In this study, the method of RNA sequencing combined with bioinformatics analysis was used to analyze the transcriptomic changes of harvested cucumber when subjected to a short-term of cold treatment. The chilling injury index (CII) and relative electrical conductivity (REC) gradually increased but the chlorophyll fluorescence (F_v/F_m) decreased with increasing time when stored at 5℃, indicating that the chilling injury was obviously occurred. Compared with that before treatment (0 h), treatment at 5℃ for 12 h resulted in 2679 differentially expressed genes (DEGs), of which 1194 DEGs were up-regulated and 1485 DEGs were down regulated. Compared with treatment for 0 h, treatment for 72 h resulted in 9494 DEGs, of which 4807 DEGs were up-regulated and 4687 DEGs were down regulated. The results of KEGG enrichment analysis showed that the DEGs caused by cold treatment were most significantly enriched in the pathways of plant hormone signal transduction, phenylalanine metabolism, plant pathway interaction and phenylpropanoid biosynthesis. The results of GO enrichment analysis showed that DEGs were mainly involved in regulation of transcription DNA templated, protein phosphorylation and transmembrane transport in biological process. In cellular component, most enriched DEGs were related to organelle components such as membrane and nucleus. In molecular function, the enriched DEGs were mainly involved in ATP binding, protein serine/threonine kinase activity, DNA binding and transcription factor activity. DEGs related to hormone signal were significantly expressed when cucumber fruits were cold-treated for 12 h. However, the DEGs related to plant pathogen interaction and phenylpropanoid synthesis were significantly induced following 72 h of cold treatment. The results showed that plant hormone participated in the transmission of low temperature signals, the induced pathogenesis-related gene and phenylpropanoid biosynthesis might be important mechanisms for harvested cucumbers to improve chilling tolerance and cope with chilling stress. The results would provide new insights into the molecular mechanisms of harvested cucumber adaptation and resistance to chilling stress, and identify a lot of key gene resources for breeding cold-tolerant cucumber.

Youjiang River Valley in Baise is one of the famous dry and hot river valleys in China. Drought is the most serious meteorological disaster in the region. It has a unique suitable environment for mango and is the main mango producing area in China. However, the research on the water use strategy of Mango in Baise dry-hot river valley region is still lacking. Based on based on the measuring of hydrogen and oxygen stable isotope of precipitation, soil water at different layers, groundwater, and mango xylem water, the variation characteristics of hydrogen-oxygen isotope an its influencing factors of precipitation were analyzed, and the water absorption sources of mango roots at different growth stages were quantified. The hydrogen-oxygen stable isotopes and d-excess had obvious seasonal changes in the year, which were low in rainy season and high in dry season. The local meteoric water line was δD=8.2587δ¹⁸O+12.308 (r=0.9968, n=35, P<0.001) for the area. Under the influence of monsoon climate, the stable isotope value of precipitation had a significantly negative linear relationship with precipitation amounts and air temperature (P<0.05). During mango flowering stage, young fruit stage, fruit expansion stage, and mature stage, the stable isotopes of soil water became poor with the increase of soil depth. In the flowering stage and young fruit stage, mango trees used a relatively uniform proportion of soil water at different depths and groundwater, while in the expansion stage and maturity stage, mango trees mainly used deep soil water and groundwater, indicating that mango trees in this area mainly use deep soil water and groundwater as water sources, as mango trees' roots are mainly distributed in deep layers, and reveals its conservative water use strategies. The variation of hydrogen-oxygen stable isotopes of precipitation indicates the xerothermic environment of Baise dry-hot river valley region, and mango mainly uses deeper soil water and groundwater, the above results are expected to provide a basis for the sustainable development of mango industry in this area.

In this study, 100 matreials of innovative germplasm from Yunnan octoploid Saccharum spontaneum L. 84-268 bloodline F₂ population were used as materials, and 7 main agronomic factors including plant height, stalk diameter, brix, effective stalk number, single stalk weight, cane yield and sugar yield were measured, and frequency distribution histogram analysis, coefficient of variation analysis, correlation analysis, principal component analysis and cluster analysis were done. The results showed that the data of the 7 agronomic traits presented a good normal distribution and abundant variation with the variation coefficient ranging from 9.91% to 50.76%, and the maximum variation coefficient of sugar yield was 50.76%. Correlation analysis and stepwise regression analysis showed that the cane yield was significantly and positively correlated with plant height, stalk diameter and effective stalk number, having a determination coefficient of 0.9282. The sugar yield was mainly determined by plant height, stalk diameter, brix, single stalk weight and effective stalk number, and the coefficient of determination was 0.9160. The seven agronomic traits were integrated into three main components by principal component analysis, and the cumulative contribution rate was 86.985%. The first principal component, cane yield and sugar factor, was the most important factor, which contributing rate was 47.615%. At the Euclidean distance of 6.00, the 100 innovative materials were divided into 3 categories, and the results were consistent with the principal component scoring. The 7 traits were excellent in group Ⅰ, and a total of 15 high-quality materials were screened out, which had a high principal component score. In particular, it was worth of paying high attention to YGF₂18-226-7, YGF₂18-226-14, YGF₂18-226-89, YGF₂18-226-48, YGF₂18-226-96, YGF₂18-226-21, YGF₂18-226-43 and YGF₂18-226-5. These materials can be further screened as the parents or reserved as core germplasm for breeding research.

In order to meet the demand for high-quality leguminous forage varieties in southern livestock production, comprehensive evaluation of the botanical characters of high-quality breeding resources is the premise of breeding. Dendrolobium triangulare is a perennial shrub with large leaves, high yield and high nutritional value. It is an excellent high-protein green feed. At present, there are only studies on the genetic diversity among the subgroups of the locust, and the analysis and research on the morphological genetic diversity of the genus Desmodium Desv. are relatively scarce, and there is a lack of research on the morphological genetic diversity of germplasm in a large range. In this experiment, a random block design was adopted, and the research materials were 76 germplasm resources of the genus Desmodium Desv. 35 botanical traits were observed, and the genetic diversity characteristics of Desmodium Desv spp. were analyzed for future breeding work of Desmodium Desv. Provide basic materials. The genetic diversity was studied by morphological observational analysis. The 35 botanical traits, the hair condition on the back of the leaf (CV=46.92%), the color of the stem (CV=39.77%) and the condition of the petiole hair (CV=39.52%) had the largest coefficients of variation, indicating that the false D. triangulare. was rich in genetic diversity. There were correlations among several botanical characters, there was a very significant positive correlation between leaf length and leaf width (r=0.887), the aspect ratio was about 2.0, and the leaf shape was close to ellipse. There was a correlation between the shape of the stem and the length of the leaf (r=-0.459) and the width of the leaf (r=-0.491), indicating that if the yield of pseudo pigeon is mainly based on the leaf area, the cylindrical stem should be selected as much as possible. There was a very significant correlation between the leaf shape of the central leaflet and the length of the pod (r=0.360), so the selection of obovate leaves during breeding could improve the seed yield. There was a very significant correlation between the hair condition on the back of the leaf, the hair condition on the petiole (r=0.462) and the hair condition on the pod (r=0.589), indicating that the hair coat condition of the same plant has a high correlation, and the resources with less hair coat on the whole plant can be screened. Through cluster analysis and systematic evaluation, four germplasm resources were screened out (D. triangulare 070314022, D. triangulare GX121121004, D. triangulare 050218087, D. triangulare 050307492), and the germplasm resources had the characteristics of high yield and high quality. This experiment explored the characteristics of genetic diversity of botanical traits among the species of D. triangulare, which could provide basic materials for subsequent breeding work.

Two new records and one mainland new record of Dematiaceous hyphomycetes from China, Beltraniella fertilis Heredia, R.M. Arias, M. Reyes & R.F. Castañeda, Subulispora cylindrospora P.M. Kirk and Subulispora procurvata Tubaki wre reported. The specimens were collected from Kuankuoshui National Nature Reserve and Xishui National Nature Reserve of Guizhou. Morphological description, figures were provided for each species, ITS and LSU sequence were provided for B. fertilis and S. procurvata. The specimens are deposited in the Mycological Herbarium of Zunyi Normal College (HMZNC).

To investigate the characteristics of plant diversity in the understory of eucalyptus plantations in Hainan, vegetation surveys were conducted in different areas of eucalyptus plantations, and the biomass of the upper part of the interior of the sample plots was measured by combining the standard wood method and the harvesting method, then theα-diversity index of the irrigation and grass layers was combined with the biomass of the above-ground part to construct a comprehensive functional index, and the new index was compared with the α diversity index. There were 101 species of understory plants in eucalyptus plantation, among which 49 species appeared in shrub layer, belonging to 45 genera of 31 families, and 52 species appeared in herb layer, belonging to 48 genera of 28 families. There was no significant difference in the diversity index of understory shrub layer in different regions of eucalyptus plantations. The α diversity index of herbaceous layer in Lingao was significantly higher than that of other areas. It means the diversity level of shrub layer was similar, while the diversity level of herb layer was more affected by environment. There were significant differences in aboveground biomass allocation between shrub layer and grass layer in different regions. Although shrub layer was larger than herb layer, the distribution ratio fluctuated widely. Yd indices of shrub layer of eucalyptus plantations in different areas had no significant difference, and Yd indices of herb layer in Lingao and Ding'an were significantly higher than those in Tunchang and Dongfang. It means that the ecological functions of shrub layer in different areas were similar, while the ecological functions of herbaceous layer were obviously stronger than those of Lingao and Ding'an. The Yd index of the shrub layer was strongly correlated with the α-diversity index; the Yd index of the herb layer was generally correlated with the α diversity index and strongly correlated with above-ground biomass. The results show that the plant diversity characteristics of the eucalyptus understory are influenced by the regional environment, with the herbaceous layer being more susceptible than the shrub layer; the α-diversity index of the shrub layer has a greater influence on the Yd index, while the above-ground biomass of the herbaceous layer has a greater influence on the Yd index. The Yd index can reflect both the α-diversity level and biomass of the understory, and is a good complement to evaluate the ecological functions of the understory vegetation of eucalyptus plantations.