The triose-phosphate/phosphate translocator (triose-phosphate/phosphate translocator, TPT) is a triose phosphate transporter that plays an important role in plant carbon metabolism pathways as well as abiotic stresses. Sucrose has a wide range of edible value and important economic value. Sugarcane is the main raw material for sugar production, and sucrose from sugarcane accounts for more than 80% of China's sugar production, so it is very important to achieve the goal of high yield and high resistance of sugarcane. In this study, the sugarcane variety ROC22 was used as the material to clone the sugarcane triose/phosphate transporter gene ShTPT, and the physicochemical properties, conserved domains, transmembrane structure prediction and protein sequence comparison of ShTPT were carried out by bioinformatics methods. The results showed that the CDS of ShTPT was 1221 bp, encoding 406 amino acids, the molecular weight of the protein was 43.63 kDa, and the isoelectric point (pI) was 9.80. It was rich in alanine and leucine, its instability coefficient was 42.51, and its hydrophilic coefficient was 0.583, which was an unstable hydrophobic protein. ShTPT did not contain signal peptides but had 9 transmembrane domains. Conserved domain prediction showed that ShTPT contained a tpt domain, which was consistent with the characteristics of the TPT family. The results of phylogenetic analysis showed that ShTPT was clustered with Sorghum bicolor SbTPT (XP_002454867.1) and Zea mays ZmTPT (NP_001105497.1) with homology of 97.04% and 94.13%, respectively. Further subcellular localization analysis of ShTPT showed that ShTPT was localized in chloroplasts. Tissue expression pattern analysis of sugarcane showed that ShTPT was mainly expressed in leaves, and the expression level in roots and stems was very low. Under the drought stress conditions simulated by PEG, the expression of ShTPT showed an upward trend, indicating that it responded to drought stress. The results of this study suggest that ShTPT is a chloroplast-localized transmembrane transporter, which may be involved in the transport of primary carbon metabolic compounds in sugarcane leaves and responsive to drought stress. This study preliminarily determined that ShTPT gene plays an important role in the transport of carbon assimilates in leaves and abiotic stress, which provides a theoretical basis for further study of its function.

Pineapple, an important tropical fruit, belongs to the family Bromeliaceae (Ananas Merr.), and its flower and fruit development theory and transcriptional regulation technology are one of the hot spots in the pineapple industry. Ethylene is one of the important hormones that regulate the flowering and fruit development of pineapple. In the study of watercore disorder in Bali pineapple varieties, it was found that two MYB transcription factors, AcMYB68 and Ac-MYB109, played an important role in fruit development. With the completion of pineapple genome sequencing, 94 pineapple R2R3-MYB transcription factors have been identified in the pineapple genome, which are divided into 26 subfamilies, and are differentially expressed by salt and other stresses and ABA hormones. In this study we proposed a scientific hypothesis that ethylene mediated MYB transcription factors to regulate the development of pineapple fruits. In order to elucidate the molecular regulatory mechanism, a MYB transcription factor AcMYB103 was cloned from the fruit of pineapple Tainong 17, with a total length of 1204 bp, a coding region of 1038 bp, and encoding 345 amino acids. The protein contains two typical SANT domains, localized to the nucleus, without transmembrane domain and signal peptide, and was a member of the plant R2R3 MYB transcription factor family. Cluster analysis of pineapple and Arabidopsis MYB family members showed that AcMYB103 had the highest similarity with Arabidopsis AtMYB80, At-MYB103 and AtMYB35, and belonged to the S19 subfamily. Furthermore, four ethephon concentrations (volume fraction) of 0%, 0.5%, 1.0% and 1.5% were used to treat the fruits at the small fruit stage, expansion stage and ripe stage of the three cultivars Tainong 17, Xiaomushousi and Damushousi, and the expression level of AcMYB103 was analyzed. The results showed that with the increase of ethephon concentration at the small fruit stage, the expression of AcMYB103 in Tainong 17 showed a down-regulated pattern, and upregulated in the Xiaomushousi and Damushousi mode. In the expansion stage, the downward adjustment pattern was shown in the Tainong 17 and Xiaomushousi varieties, and the upward pattern was shown in the fruit of Damushousi. AcMYB103 was not expressed in fruits at the ripening stage, indicating that the expression of AcMYB103 gene was specific in ethephon-treated varieties and fruit development periods, and played a differentiated regulatory role in the early stage of fruit development. This study would lay a foundation for in-depth study of the mechanism of AcMYB103 gene in the regulation of growth and development of pineapple fruit.

Pineapple is prone to intern browning during storage at room temperature. Diseased and healthy parts of pineapple at early stage of intern browning were used to explore the mechanism of the disease. Three samples from each part were used for transcriptome RNA-Seq analysis. GO, KEGG, cluster analysis of gene expression in various metabolic pathways, and RT-qPCR validation on differential genes were performed and the differential gene expression levels between the diseased (IB) and healthy (WT) parts were compared. IB vs WT had 1037 differentially expressed genes, of which 886 were up-regulated and 130 were down-regulated. GO and KEGG analysis found that the differentially expressed genes in amino acid biosynthesis were the most significant, and the proportion of differentially expressed genes was large. Cluster analysis and RT-qPCR validation found that the sugar metabolism pathway significantly up-regulated the expression levels of related enzyme genes in glycolysis, tricarboxylic acid cycle (TCA), and oxidative phosphorylation processes after fruit disease onset. The response of plants to external environmental signaling pathways revealed a significant down-regulation of resistance enzyme gene expression, a significant up-regulation of pathogenic protein gene expression, and a significant down-regulation of resistance protein gene expression. The antioxidant pathway revealed significant down-regulation of glutathione synthesis gene expression, significant up-regulation of flavonoid biosynthesis related gene expression, significant down-regulation of L-ascorbate peroxidase (APX) gene expression, and significant up-regulation of L-ascorbate oxidase (AOX) homologous gene expression. RNA-Seq and RT-qPCR analysis indicated that pineapple tissue significantly up-regulated key genes in sugar metabolism to accelerate sugar metabolism in fruit disease part, significantly up-regulated key genes in the MAPK signaling pathway, and significantly down-regulated metabolic pathway changes such as antioxidant substances, leading to pineapple intern browning. The results could enrich the gene network of pineapple intern browning and provide a valuable reference for the subsequent gene screening of pineapple intern browning.

Chalcone synthase is a crucial enzyme in the initial stage of the flavonoid biosynthetic pathway. To explore the biological functions of our previously identified chalcone synthase coding gene DlCHS9 from longan, which is associated with anthocyanin accumulation, DlCHS9-SX and DlCHS9-HP from Shixia and Hongpi longan, were cloned respectively. Amino acid sequences of DlCHS9-SX and DlCHS9-HP were compared and found to differ only at position 328, which was not a key active site. Subsequently, an expression vector was created, and the Agrobacterium-mediated leaf disc method was used to introduce DlCHS9-SX into wild tobacco. The anthocyanin content in the petals of transgenic tobacco was notably higher than that in the wild type, suggesting that the DlCHS9-SX gene enhances anthocyanin accumulation in tobacco petals. The promoter sequences of the two DlCHS9 genes revealed a similarity of 96.2%. Compared to the promoter of DlCHS9-HP, the promoter of DlCHS9-SX had 32 SNPs, 14 base insertions, and 12 base deletions. Specifically, the DlCHS9-SX promoter contained an additional abscisic acid responsive element (ABRE), one fewer light-responsive element (Box4), one less low temperature-responsive element (LTR), and one less MYC transcription factor binding site. In conclusion, DlCHS9-SX plays a pivotal role as a structural gene in longan anthocyanin biosynthesis. The differences in the DlCHS9 promoter in Shixia longan may contribute to its lower expression level.

Cold resistance and high-yielding are always the core breeding objectives of Yunnan rubber tree planting area in China. The superior clone was selected by artificial hybridization, and was systematically identified by nursery trial, advanced clonal trial and resistance test. The results showed that Yunyan 80-1983 was a fast-growing, high-yielding and early-maturing rubber tree clone which could be tapped 0.5-1 years earlier. In advanced clonal trials, the girth reached 52.7 cm in the seventh year, which was 122.6% of the control RRIM600 (43.0 cm). The dry rubber yield of 1-13 tapping year was 4.3 kg per tree and 1622.7 kg/hm², which was 130.3% and 122.5% of the control RRIM600 (3.3 kg per tree,1324.8 kg/hm²). The cold resistance was basically equivalent to that of RRIM600, lower than that of GT1 and Yunyan 77-4. It is recommended to be planted in the low-altitude and slight cold damage zone in Yunnan. This clone would provide variety support for optimizing the variety structure, increasing the yield and output value in Yunnan and other rubber planting areas.

The introduction and evaluation of foreign clones play an important role in promoting the development of rubber trees in China. In order to evaluate the adaptability of Indonesian rubber tree clone Reshi 11-107, the stem circumference growth, dry rubber yield, rubber production and discharge characteristics, and natural rubber quality were examined in the clone trail test, which was arranged according to the breeding technical regulations. The average annual stem girth of Reshi 11-107 increased by 7.6 cm before tapping, and increased by 3.0 cm after tapping, and the fast-growing characteristics were obvious. The average yield was 58.41 g and the dry gum content was 33.37% in the first 5 tapping years, which were significantly better than that of the control clone RRIM600. Reshi 11-107 has a large number of laticifers in the bark, the initial flow rate of rubber discharge is fast, the plug index is low, the thiol content is significantly higher than that of the control, and the sucrose content is equivalent to that of the control. It has good characteristics of rubber production and discharge, better potential for rubber production, and good adaptability to cold damage. Reshi 11-107 natural rubber has large molecular weight, high ash content, high initial plasticity value, high tensile strength, high tear strength and good physical and mechanical properties. In conclusion, the comprehensive characters of Reshi 11-107 are better, which could adapt to the planting environment in China, and could be expanded in the type I planting area.

Sugarcane mosaic disease is one of the main viral diseases threatening the production of sugarcane. Sugarcane streak mosaic virus (SCSMV), Sorghum mosaic virus (SrMV) and Sugarcane mosaic virus (SCMV) are the main pathogens. The occurrence of sugarcane mosaic disease seriously affects the quality and yield of sugarcane. The most economical and effective way to control the disease is the application of resistant varieties. In this paper, the damage and controlling ways of sugarcane mosaic disease were summarized. The recent research progress on identification of resistance germplasm resources, resistance inheritance, molecular markers, mining and application of the resistance gene, and breeding of disease-resistant varieties were reviewed. Moreover, the problems existing in sugarcane disease resistance breeding were pointed out, and some suggestions were put forward to strengthen the research on sugarcane mosaic disease resistance breeding.

Sugarcane pokkah boeng disease (PBD) is a major disease of sugarcane in China, which severely affects the yield of sugarcane and causes significant economic losses. Selection and cultivation of PBD resistant sugarcane germplasms is the most economical and effective control method. In this study, a three-year field experiment was conducted in Dingdang of Guangxi, and Dehong of Yunnan to analyze the natural disease data of sugarcane PBD from 2015 to 2017. The objective was to evaluate the disease resistance of 98 sugarcane germplasms in China and provide a reference for breeding disease-resistant sugarcane. The results indicated significant difference between different regions, with the average incidence and disease index higher in Dingdang than Dehong. Joint analysis of variance (ANOVA) showed that germplasms, year, location, month, germplasms×year, germplasms×location and location×month had a significant impact on the incidence and disease index of tip rot (P<0.001). Among them, genotype and year had the greatest impact, indicating that PBD is mainly controlled by genetic and environmental factors. A comparison of meteorological conditions at various locations revealed a positive correlation trend between the PBD occurrence, air temperature, and annual rainfall. The 98 sugarcane germplasms were categorized into five groups, out of which 16 (16.33%) were highly resistant, 32 (32.65%) were resistant, 18 (18.37%) were moderately susceptible, 24 (24.49%) were susceptible, and 8 (8.16%) were highly susceptible. Highly resistant germplasms such as CP94-1100, Q202, ROC21, ROC23, Yuetang 93-159, Guitang 02-1247, Guitang 02-208, Guitang 02-761, Guitang 03-1403, Yuegan 16, Guitang 05-3846, Guitang 05-827, ROC22, Yuetang 00-236, Yuetang 89-240, and Yuetang 94-128 are recommended as the parents for disease resistance breeding. Conversely, highly susceptibility germplasms such as CP72-2086, PINDAR, ROC26, Guitang 02-619, Guitang 05-2743, Guitang 05-322, Liucheng 03-182, and Shuidian 25, should be used with caution. This study distinguished germplasms with stable resistance in different environments, which is significant for germplasm utilization and the breeding of resistant germplasms.

Cassava variety Nanzhi 199 (sweet cassava variety, with erect, compact plant shape and generally unbranched at the top) and chili pepper variety Xiangyan 55 (medium maturity small cowpea variety, with good growth and strong adaptability) were used to study the effects of cassava-pepper intercropping pattern on cassava growth, photosynthetic performance, soil enzyme activity, tuber yield and quality. Three different planting densities of chili peppers in chili peppers and cassava intercropping (T₁, T₂ and T₃, with the spacing of 0.4 m, 0.5 m and 0.6 m, respectively) were designed. The results showed that the aboveground growth indexes of cassava under intercropping treatment had different degrees of inhibition in various growth periods of cassava, and the inhibitory effect deepened with the increase of density and time, so the aboveground plant height and stem thickness of T₃ treatment were minimally inhibited; intercropping treatments were able to improve the relative chlorophyll content of cassava seedling leaves, and the intercropping treatments were able to increase the net photosynthetic rate of the whole period of potato production, stomatal conductance, and the cytosolic rate of the tuber expansion period, and intercellular carbon dioxide concentration during tuber expansion, but had no significant effect on the transpiration rate of cassava in all growth periods; intercropping treatments significantly increased the activities of soil urease, acid phosphatase, catalase and sucrase compared with CK, and the activities of the soil enzymes were significantly higher than those of other intercropping treatments by T₃ except for the activity of soil catalase which had no significant difference among the intercropping treatments; intercropping reduced the aboveground biomass and belowground biomass, and the activity of soil enzymes by T₃; intercropping reduced the relative chlorophyll content of cassava leaves at seedling stage. Although intercropping reduced the above-ground biomass and the number of cassava tubers in the below-ground part, it could improve the weight of cassava, and there was no significant difference between intercropping T₁ and T₂ treatments and the yield of CK, while the acreage yield of T₃ was significantly increased by 13.98%; intercropping could effectively improve the quality of tubers, and the contents of various qualities other than soluble sugar and cellulose in T₃ treatment were significantly higher than that of other treatments, among which, the intercropping treatments were able to increase the starch content of cassava tubers to different degrees, respectively, and increased the starch content of cassava tubers to different degrees. Among them, intercropping treatments were able to increase the starch content of cassava tubers to different degrees, which was increased by 13.06%, 8.25% and 19.33% respectively. In summary, cassava intercropping can improve the yield and quality of cassava tubers by increasing the photosynthetic rate and soil enzyme activity of cassava, and then increase the economic benefits of cassava. Finally, the T₃ treatment with 2 rows of cassava and 2 rows of chili peppers (plant spacing 0.6 m) had the optimal cultivation density, which was a suitable cassava-chili pepper intercropping pattern for Hunan production area.

In view of the deficiency of calcium (Ca), magnesium (Mg), zinc (Zn) and boron (B) in the production of macadamia in Yunnan province, the accumulation characteristics of Ca, Mg, Zn and B in litter, pruned branch and nuts harvest were analyzed to provide a theoretical basis for the optimal management of Ca, Mg, Zn and B nutrients and help the quality and efficiency production of macadamia. In 2021 and 2022, high-yielding trees of macadamia nut variety A16 were used as the test materials to study the quality of dry matter, the content of Ca, Mg, Zn and B nutrients and their cumulative distribution during litter, pruned branch and nuts harvest. The average dry matter weight of litter, pruned branch and nuts harvest of macadamia t was 35.77 kg/plant, among which litter, pruned branch and nuts harvest accounted for 19%, 32% and 49% of the total dry matter weight, respectively. There were significant differences in the content of Ca, Mg, Zn and B nutrients in different tissues, and the overall performance was Ca>Mg>B>Zn. The average cumulative amounts of Ca, Mg, Zn and B in 2 years was 126.13, 23.39, 0.25 g/plant and 0.89 g/plant, respectively. The cumulative distribution of Ca and Mg in litter, pruned branch and nuts harvest was 45%, 48% and 7%, and 26%, 33% and 41%, respectively. The cumulative distribution of Zn was 25%, 28% and 47%, and the cumulative distribution of B was 44%, 36% and 20%, respectively. Among them, leaves (senescent leaves and pruning leaves) were the main accumulation and distribution parts of Ca and B, while pruning leaves and nuts were the main accumulation and distribution parts of Mg and Zn. The estimated apparent nutrient balance indicated that the total nutrient taken by Ca, Mg, Zn and B was 45.41, 8.42, 0.09 kg/hm² and 0.32 kg/hm². After removing some nutrients returned by litter, in the absence of exogenous Ca and Mg input and the input of Zn and B 0.08 kg/hm², Ca, Mg and B nutrients were deficient in macadamia. The results would provide the basis for nutrient optimization management of macadamia.