In order to determine the optimal conditions for the preparation of jackfruit starch-coconut oil complexes by Rapid Visco Analyzer (RVA), the influence of addition of coconut oil, complexation time and complexation temperature on the complexation index of jackfruit starch-coconut oil complexes was studied. The Box-Benhnken response surface method was used to optimize the process conditions for the preparation of jackfruit starch-coconut oil complexes. The optimal preparation parameters of the jackfruit starch-coconut oil complexes were 4% of the addition of coconut oil, 2.40 min of complexation time, 90.70 ℃ of complexation temperature, respectively. Under the optimal condition, the experimental value of complex index was 24.33%, which was in good agreement with the value predicted by the model (24.64%). The gelatinization temperature, peak viscosity, and though viscosity of jackfruit starch-coconut oil complexes were higher than those of the raw starch, while the final viscosity and setback value were lower than those of the raw starch. This indicated the thermal stability of the complex was improved. The swelling ability of the starch was restricted when the jackfruit starch-coconut oil complexes was formed, resulting in the lower swelling power and a lower solubility than those of the raw starch.

Neonicotinoids (NEOs) contain imidacloprid (IMI) and acetamiprid (ACE), which are widely used in the world. In this study, earthworms (Eisenia foetida) were used as soil animal. Through high-throughput sequencing and measurement of soil physical and chemical properties, the changes of bacterial communities between IMI and ACE contaminated red soil (BCK, DCK) and soil after earthworm introduction (B, D), and the relationship with environmental factors were analyzed to explore the animal remediation mechanism of contaminated red soil. The introduction of IMI and ACE reduced the diversity of microbial population, significantly changed the composition of soil bacterial community structure, and decreased the content of soil organic matter (SOM) and total nitrogen (TN), compared with the natural red soil (CK). The addition of earthworms increased the relative abundance of Actinobacteriota, Proteobacteria and Bacteroidota, which have the ability of insecticide resistance and degrading. pH value, TN, total phosphorus (TP) and total potassium (TK) contents of contaminated soil increased. Combined with the correlation analysis of soil physiochemical properties, it was found that pH, TN, TK and SOM had a great influence on the bacterial community structure among the treatment groups at the genus level. The study showed that IMI and ACE pollution reduced the contents of SOM and soil TN, and destructed the original bacterial community structure in the soil. Earthworm activity improved soil fertility of contaminated red soil, alleviated the adverse effects of IMI and ACE on soil microbial flora, restored and enriched the diversity of microbial species in NEOs-contaminated soil to a certain extent, and then accelerated the degradation of NEOs in soil. This study showed the feasibility to screen the efficiently IMI and ACE-degrading bacteria from drilosphere, and would provide theoretical basis for the earthworm remediation of IMI and ACE-contaminated soil.

A technique system for detecting the genome size of Camellia oleifera by flow cytometry was established to analyze the genome size genetic diversity between the superior lines of C. osmantha var. Yilu and C. vietnamensis var. Hongu 23, and to provide reference for selection of special germplasm and analysis of ploidy difference, based on the key links such as the type of dissociated liquid, the plant of internal reference, the tissue organ of the test material, evaluation indexes such as the nuclear dissociation, the degradation of secondary metabolites, the stability of the cell peak, the clear degree of the main peak, the separation degree of the main and miscellaneous peak, the easy degree of sampling, the difference of the genome size of the internal participating samples, the accuracy of genome size determination and the coefficient of variation. The method was used to determine the genome size of the superior lines of C. osmantha and C. vietnamensis. The disintegrating effect of WPB and mG^b was better among common dissociative fluids WPB, Tris-MgCl₂, OTTO, mG^b. Pean and corn were the favorable internal plants, and young leaf or root tip were the favorable experimental materials. The genome size of the superior lines of C. osmantha was from 5.12 to 9.31 Gb, with an average value of 7.60 Gb, the genome size distribution of the superior lines No. 1, No. 37 and No. 45 was extreme, and it was speculated that there were ploidy differences or interspecific hybridization between the parents. The genome size of superior lines of C. vietnamensis varied from 9.17 to 9.85 Gb, the mean value was 9.47 Gb. There was significant difference in genome size between the superior lines of C. osmantha and C. vietnamensis.

Chili pepper (Capsicum annuum) is an important vegetable and condiment, but the current cropping pattern makes its continuous cropping obstacles increasingly prominent. Most studies show that reasonable rotation is an effective method and means to solve the continuous cropping obstacles of chili pepper. Industrial hemp (Cannabis sativa) is an ideal rotation plant, but the effect of industrial hemp rotation on alleviating the continuous cropping obstacle of chili pepper is not clear. In order to explore the effect of industrial hemp-chili pepper rotation on the growth and physiology of chili pepper, this study took the industrial hemp variety Yunma 1 and two local chili pepper varieties Taiyanghong and Yangjiaola as the materials in the agronomic experiment greenhouse of Yunnan University from 2018 to 2019. Pot experiments were carried out on chili pepper continuous cropping and industrial hemp-chili pepper rotation, respectively. The morphological growth and physiological and biochemical indexes of chili pepper after industrial hemp rotation were comparatively analyzed, and the effect of industrial hemp rotation on the growth and physiology of chili pepper in the later season was preliminarily explored. The results showed that the main physiological and biochemical indexes of chili pepper in the rotation group and the continuous cropping group had the same trend. However, compared with the chili pepper continuous cropping, the chlorophyll content of the two chili pepper varieties increased to a certain extent at 40, 50, 60 and 100 days after seedling thinning, while the activities of antioxidant enzymes (SOD and POD) and root activity also increased correspondingly, especially in the harvest period (100 days after seedling thinning) in the industrial hemp-chili pepper rotation. After the industrial hemp rotation, the net photosynthetic rate (P_n), stomatal conductance (G_s), intercellular CO₂ concentration (C_i) and transpiration rate (T_r) of the leaves of the two pepper varieties were significantly increased at 40, 50 and 60 days after seedling thinning, resulting in a significant increase in plant height, stem diameter, shoot dry weight and root shoot ratio at harvest stage. Compared with the chili pepper continuous cropping, the plant height of Yangjiaola and Taiyanghong increased by 20.65% and 16.85%, the stem diameter increased by 16.32% and 19.94%, the aboveground dry weight increased by 15.39% and 27.50%, and the root shoot ratio increased by 33.26% and 25.47% in the industrial hemp-chili pepper rotation, respectively. In conclusion, the industrial hemp rotation enhanced the physiological activity of late season chili pepper and better maintained the normal growth and development of chili pepper. The results have a guiding significance for the selection of reasonable planting mode of chili pepper in the future.

Rubber tree is an important economic tree species. In order to explore the reasonable amount of fertilization in rubber plantations, field experiments with different nitrogen fertilizer dosages were set up to clarify the nitrogen transportion characteristics of rubber plantations after mid- and late-stage fertilization. Four treatments were set up: ① blank control (CK), no fertilization; ② conventional fertilization (C, total fertilization 2 kg/plant, early stage∶middle stage∶late stage=5∶3∶2); ③ reduced fertilization (J, total fertilization 1.6 kg/plant, early stage : mid dle stage∶late stage=5∶3∶2), and the reduction of fertilization is equivalent to a 20% reduction in conventional fertilization; ④ simultaneous fertilization (T, total fertilization 1.6 kg/plant, early stage∶middle stage∶late stage=3∶3∶2). The results showed that the characteristics of soil nitrogen transportion in rubber plantations with different fer tilization treatments were different, mainly vertical transportion, and horizontal transportion fluctuated significantly within 5 cm, and there was no obvious change with the increase of horizontal distance. The ammonium nitrogen in the mid-term fertilization mainly transported to 40-60 cm, while the ammonium nitrogen in the later fertilization mainly stayed at 0-20 cm. The trend of inorganic nitrogen was consistent with that of ammonium nitrogen, the main form of soil inorganic nitrogen under different fertilization treatments was ammonium nitrogen. The transportation ability of both ammonium and nitrate nitrogen was reduced and the transportation to deep soil was reduced in the late fertilization. Therefore, adjusting the amount and time of fertilization is beneficial to improving the utilization rate of nitrogen fertilizer in rubber plantations and reduce nitrogen loss.

Pitaya has both edible and medicinal value, the major fruit in tropical and subtropical regions of China. But it is susceptible to diseases during storage. Pitaya soft rot disease is a common major disease in storage. To clarify the pathogen of pitaya soft rot, the antagonist activity and inhibition effect of antagonistic actinomycetes against pathogen, pitaya with soft rot characteristics were used to isolate pathogens by tissue separation, purification and identification. The pathogenicity of pathogen was determined by inoculated without injuries and fruit acupuncture inoculation. 26 Streptomyces spp. as the antagonist strains were tested. The inhibitory effects of cell-free filtrate on mycelial growth of the pathogen were studied by agar block method and growth rate methods. Control effect of LWL1827 cell-free filtrate spraying of different concentration and PPO, POD and PAL activity of concentration 1∶10 were carried out. ZYW18 was the pathogenic fungus according to the pathogenicity test, which was identified as Fusarium verticillioides based on morphological characteristics and molecular identification. LWL1827 could significantly inhibit the mycelia growth of ZYW18, the radius of inhibition zone was (18.32±2.13)mm, and the colony extension was inhibited significantly, the inhibitary rates of sterile fermentation filtrates with different concentrations of 1∶5、1∶10、1∶50 was 91.23%±3.11%, 87.21%±3.22%, 80.22%±2.03%, respectively. LWL1827 cell-free filtrate (1∶10) significantly improved the activity of PPO, POD and PAL, even 2-3 times higher than that of the control. Meanwhile, LWL1827 could reduce disease index and improve its control effect. Conclusively, the pathogen that causes pitaya is identified as F. verticillioides. This is the first report of pitaya caused by F. verticillioides. The Streptomyces sp. LWL1827 has significant antagonistic effect, and the antagonistic strain LWL1827 has potential value in biological control against pitaya soft sot.

A field experiment was conducted to investigate the effects of different fertilization and irrigation rates on plant growth, nutrient uptake, yield and fruit quality of MD-2 pineapple. The goal was to deal with the seasonal drought in the main producing areas of pineapple, and determine the appropriate rates of fertilization and irrigation for high-yield and high-quality pineapple variety growth, which can increase the yield and efficiency. MD-2 pineapple was subjected to a field plot experiment with eight treatments: (1) CK (no fertilization and no irrigation), (2) F₁W₀ (no irrigation with conventional fertilization), (3) F₁W₁ (fertigation with 50%-60% of field capacity), (4) F₂W₁ (25% reduction in fertilizer application with 50%-60% of field capacity), (5) F₃W₁ (50% reduction in fertilizer application with 50%-60% of field capacity), (6) F₁W₂ (fertigation with 30%-40% of field capacity), (7) F₂W₂ (the amount of fertilizer was reduced by 25%, 30%-40% of field capacity), and (8) F₃W₂ (the amount of fertilizer was reduced by 50%, 30%-40% of field capacity). The results showed that the total number of leaves, root, stem, leaf, stalk, fruit and plant dry biomass accumulations, and plant N, P, K accumulations of MD-2 pineapple of F₁W₁ treatment were significantly higher than those of CK. Compared with F₁W₀, F₁W₁ treatment significantly increased the plant height, stem height, stem diameter, D leaf length, D leaf width, peduncle diameter, and stem, leaf, peduncle, fruit and plant dry biomass accumulations, and N and K accumulations of plant. The transverse diameter, vertical diameter, fruit weight and fruit yield of MD-2 pineapple of F₁W₁ treatment were significantly higher than those of CK and F₁W₀. And the fruit yield of F₁W₁ was 117.46% higher than CK and 99.40% higher than F₁W₀, while there was no difference between F₁W₀ and CK. The fertilizer contribution rate and agricultural efficiency of each fertigation treatment were significantly higher than those of F₁W₀. The contents of vitamin C and titratable acid of F₁W₀ were the highest, but the sugar-acid ratio was the lowest. Under the same irrigation level, there were no significant differences in growth, dry biomass accumulation and fruit quality of MD-2 pineapple among different fertilization levels. The yield of F₁W₁ treatment was the highest, which had no significant difference with that of F₃W₁ treatment. The irrigation water productivity of F₃W₁ treatment was equivalent to that of all treatments with low irrigation level. Under the same fertilization level, the soluble sugar content and sugar-acid ratio of treatments with high irrigation rate were significantly higher than those of treatments with low irrigation rate. Considering the growth situation, yield and quality of MD-2 pineapple, irrigation water productivity and fertilizer contribution rate, F₃W₁ treatment was the optimal combination of fertilization and irrigation, which was beneficial to realize high yield, quality and efficiency of MD-2 pineapple.

Paris polyphylla var. alba, a medicinal plant of Melanthiaceae, is classed as the national second-grade protected species of China. With the increasing demand for raw materials of Rhizoma paridis, the wild resources of P. polyphylla var. alba have been seriously damaged. In order to protect the genetic resources and clarify the systematic positon of this species, Illumina Hiseq X Ten platform was used to sequence the chloroplast (cp) genome. The structural characteristics of the complete cp genome sequence and phylogenetic relationship of P. polyphylla var. alba in Paris were analyzed. The results showed that the cp genome was 163 944 bp in length with a typical quadripartite structure with a large single-copy (LSC) region of 84 179 bp, a small single-copy (SSC) region of 12 967 bp, and a pair of 33 399 bp inverted repeats (IRs). The genome contained 134 genes, including 88 protein-coding genes (PCGs), 38 tRNA genes and 8 rRNA genes. A total of 645 long repeats and 97 simple sequence repeats (SSRs) loci were detected in the complete cp genome, in which forward and palindromic repeats were the mainly long repeat types, and most of SSRs had A/T base preference. Phylogenetic analysis based on the complete cp genomes showed that Paris formed a monophyletic group, and could be further divided into five major clades corresponding to five sections, respectively. The varieties of P. polyphylla are located in Sect. Euthyra, but are not clustered a monophyletic group, and P. polyphylla var. alba is closely related to P. mairei. This study would provide a scientific basis for studying the phylogeny, species identification and resource conservation of Paris.

During the evolution from lower plants to higher plants, lignification is the key to adapt to the terrestrial environment, while lignin deposition in the cell wall is an important manifestation of lignification, and MYB61 plays an important role in lignin synthesis pathway. In order to explore the molecular mechanism of MYB61 in lignin synthesis of Impatiens chlorosepala and Impatiens uliginosa, MYB61 genes, named IcMYB61 and IuMYB61 in this study, were cloned by using the RT-PCR method. The full-length cDNA was 1035 bp and 1002 bp, encoding 344 aa and 333 aa, containing an intron of 84 bp and 66 bp, respectively. Physicochemical analysis suggested that IcMYB61 and IuMYB61 were unstable hydrophilic protein. Domain analysis of protein showed that IcMYB61 and IuMYB61 contained two typical SANT conserved domains. The comparison of amino acid sequences of MYB61 with that of other species showed that there were highly conserved R2 and R3 regions at the N-terminal, which was speculated to be R2R3-MYB gene. Based on the phylogenetic analysis, it found that IcMYB61 and IuMYB61 were clustered together with I. glandulifera, confirming that the same genus is more closely related. The qPCR showed that IcMYB61 and IuMYB61 were expressed in three different parts of the two periods, and the expression levels were the lowest in roots. In I. chlorosepala, the highest expression of IcMYB61 was in the leaves at the seedling stage, and the highest expression level was in the stem at the mature stage. In I. uliginosa, the expression of IuMYB61 was the highest in the stems of both periods. By measuring the total lignin content in stems and leaves of the two species, it was found that the lignin content of both species was the highest in stems, which was consistent with the expression trend of MYB61. It is speculated that MYB61 mainly regulates the biosynthesis of lignin in the stems of I. chlorosepala and I. uliginosa. The above-mentioned results would provide some basic data and scientific basis for exploring the regulation mechanism of MYB61 on the lignin synthesis of Impatiens and the culture of new varieties.

Phosphorus is an indispensable element in the process of plant growth and development, but it is mostly in the form of ineffective bound phosphorus in the field. The microorganisms in soil can convert the ineffective phosphorus into free effective phosphorus, and fully improve the utilization rate of phosphorus. In this study, a phosphate-solubilizing fungus XZY3PSF was isolated and purified from the corn rhizosphere soil using the phosphorus-solubilized halo method, and the strain was identified. The activity of the strain to dissolve 2.5-20.0 g/L tricalcium phosphate and the phosphate solubilization ability of 10-10⁵ spores/mL to tricalcium phosphate in 1-25 d were analyzed. The mineralization ability of 2.5 g/L and 5.0 g/L calcium phytate was evaluated, and the interaction between it and Bacillus amyloliquefaciens and the pathogen of banana Fusarium wilt disease was evaluated. Based on the morphological characteristics combined with ITS and β-tubulin gene sequences, the strain XZY3PSF was identified as Talaromyces purpureogenus. The highest content of available phosphorus dissolved by phosphate-solubilizing strain under different concentrations of tricalcium phosphate was between 500 and 570 mg/L. The content of available phosphorus in the medium decreased with the prolongation of culture time. The decreasing range of the available phosphorus content in the tricalcium phosphate medium was weakened. On the 25th day, the available phosphorus content in the 15.0 and 20.0 g/L tricalcium phosphate medium was significantly higher than that of the other concentrations. With the increase of the spore concentration in the medium, higher peak value of the available phosphorus content in the culture medium appeared, and its decreasing range expanded with the increase of the spore concentration. During the test period, with the extension of culture time, the mineralization ability of XZY3PSF to calcium phytate was stronger. XZY3PSF and Bacillus X5 had antagonistic effects on the pathogen of banan Fusarium wilt, but the phosphate solubilizing fungus and Bacillus spp. also antagonized each other. The research results would lay a foundation for the development of microbial fertilizers composed of phosphorus-solubilizing fungi and antagonistic bacteria. At the same time, the mineralization of XZY3PSF on calcium phytate would provide a basic theoretical basis for subsequent studies on whether it can degrade organophosphorus pesticides.