Various Organic Nutrient Sources in Combinations with Inorganic Fertilizers Influence the Yield and Quality of Sweet Corn(Zea mays L.saccharata)in New Alluvial Soils of West Bengal,India

Nutrient management plays a crucial role in the yield and quality of sweet corn.A field experiment was conducted in consecutive two kharif seasons in 2018 and 2019 to investigate the effect of various organic sources of nutrients in combination with inorganic sources on the yield and quality of sweet corn under new alluvial soils of West Bengal,India.Treatments were:T_(1):Control(without fertilizers);T_(2):100%recommended dose(RDF)of chemical fertilizers(CF)(RDF CF_(100%));T_(3):100%recommended dose of N(RDN)through vermicompost(VC)(RDN VC_(100%));T_(4):50 RDN through CF+50%RDN through VC(RDN CF_(50%)+RDN VC50%);T_(5):50%RDF through CF+50%RDN through organic source(OS)1,Soligro(Ascophyllum nodosum)granular(RDN CF_(50%)+RDN OS_(150%));T6:50%RDN through CF+50%RDN through OS 2,Bioenzyme(liquid)(RDN CF_(50%)+RDN OS250%);T7:50%RDN through CF+50%RDN through OS 3,Opteine(Ascophyllum nodosum)filtrate[RDN CF_(50%)+RDN OS350%];T8:50%RDN through VC+50%RDF through OS 1,Soligro(Ascophyllum nodosum)granular(RDN VC50%+RDN OS_(150%)).The OS of fertilizers were VC,SoliGro Gr(OS1)(Ascophyllum nodosum),Bioenzyme liquid(OS2),and Opteine(Ascophyllum nodosum)filtrate(OS3).The inorganic source was traditional CF applied at the RDF(150:75:75 kg ha^(−1) of N:P2O5:K2O).The VC was used to supply 100%RDN as one source or 50%RDN when combined with CF or OS.Maximum fruit yield(10.75 and 10.79 t ha^(−1) in 2018 and 2019,respectively)was recorded when RDF was substituted through CF only,being statistically at par with 50%CF+50%VC on a nitrogen equivalent basis(9.92 and 10.00 t ha^(−1) in 2018 and 2019,respectively)and 100%VC(8.22 and 8.32 t ha^(−1) in 2018 and 2019,respectively).Compared to chemical sources of nutrients,VC-based treatments produced a larger percentage of large-size cob(>25 cm).The 100%VC increased antioxidant(8.35 and 8.45 mg g^(−1)),carotenoid(0.59 and 0.61 mg/100 g),and phenol(55.06 and 55.02 mg 100 g^(−1))content compared with its 50%dose in combination with other sources.The study revealed the potentiality of organic sources towards achieving improved cob quality of sweet corn.

Hypoglycemic effect and the mechanism of action of a polysaccharide from sweet corncob in a high-fat diet and streptozotocin-induced diabetic mice

Type 2 diabetes mellitus(T2DM)is a metabolic disease caused by a glycolipid metabolism disorder and isletβ-cell dysfunction.SCP-80-I is a biologically active water-soluble polysaccharide isolated from sweet corncob,an agricultural byproduct.The hypoglycemic effects of SCP-80-I on T2DM mice and its mechanisms were investigated in this study.SCP-80-I was found to significantly reduce blood glucose and lipid deposition levels in T2DM mice,as well as decrease serum leptin and increase adiponectin secretion.Interestingly,real time-polymerase chain reaction(RT-PCR)and Western blotting results revealed that SCP-80-I could regulate the expression of several glycolipid metabolisms and insulin secretion genes and proteins,including 5'-AMP-activated protein kinase(AMPK),carnitine palmitoyltransferase I(CPTI),and acetyl coenzyme A carboxylase(ACC)in the liver and AMPK,sirtuin1(Sirtl),peroxisome proliferator-activated receptorycoactivator-1(PGC-1α),and uncoupling protein 2(UCP2)in the pancreas.To have a hypoglycemic effect,SCP-80-1 regulated glycolipid metabolism and islet cell function in the liver by regulating the AMPK/AC C/CPT1 signaling pathway and the AMPK/Sirt1/PGC-1αand AMPK/Sirtl/UCP2 signaling pathways.These findings improve our understanding of polysaccharides derived from sweet corncob and the use of SCP-80-I in the production of hypoglycemic foods.

Efficient Cultivation Mode and Benefit Analysis on Sweet Corn

[Objective] In order to research differences of economic benefits among 5planting patterns of sweet corn. [Method] Planting benefit of five kinds of planting patterns of Ditian6 were studied. They were one cropping of sweet corn per year,two cropping of sweet corn per year, multiple sowing of wheat and sweet corn, intercropping of sweet corn and vegetables（potatoes, peppers）. [Result] Planting benefit of two cropping of sweet corn in a year, multiple sowing of wheat and sweet,intercropping of sweet corn and vegetables（potatoes, peppers） were higher than that of sweet corn monoculture. The benefit of two cropping of sweet corn per year was the highest, which was 93 937.5 yuan/hm^2. The pure income increase was 41 610 yuan if the average investment of 18 480 yuan/hm^2 was eliminated. Compared with wheat monoculture, the benefit of multiple sowing of wheat and sweet increased39 060 yuan/hm^2. The pure income increase was 25 500 yuan if the average investment of 13 560 yuan/hm^2 was eliminated. The planting benefit of intercropping of sweet corn and potato was 71 460 yuan, and that of intercropping of sweet corn and pepper was 63 750 yuan. [Conclusion] There were extremely significant differences among the economic benefits of 5 planting patterns of sweet corn. According to local actual situation, farmers can choose the most suitable pattern to improve the planting efficiency of the sweet corn.

Variation Law of Pericarp Tenderness of Super Sweet Corn Kernel

To investigate the variation law of pericarp tenderness in growth progress of super sweet corn kernel, the values of pericarp tenderness of 10 super sweet corn inbreeds were measured during kernel growth, and the variations under differ- ent conditions were analyzed. The results showed that there existed gradient differ- ences in pericarp tenderness among the 10 materials, of which PE10 had the best pericarp tenderness, T105 took medial place, and $33205 performed worst in peri- carp tenderness. Pericarp tenderness values of these 3 inbreeds increased curvedly from 12 to 24 days after pollination, in the spring （Wuhan, Hubei） and winter （Ling- shui, Hainan） of 2014. Moreover, the average pericarp tenderness at different time points presented the same decreasing order of $33205, T105, PE10, which was not altered by enviroment. With the growth of kernel, for one material, the difference of pericarp tenderness under different environments presented a law of increment, re- duction, uniformity. As for optimum-picking time, there was four days difference be- tween the spring in Wuhan and winter in Lingshui. However, there was no obvious difference in pericarp tenderness on the optimum picking time, which indicated that growing environment could affect the variation ratio of pericarp tenderness, but it still depended on the nature of materials.

枸杞SWEET基因家族鉴定及其与可溶性糖含量关系

【目的】糖外排转运蛋白(sugars will eventually be exported transporters,SWEETs)在植物生长发育过程中发挥重要作用,解析SWEETs基因在枸杞果实发育过程中对糖积累作用,为进一步揭示SWEETs基因在枸杞果实发育过程中的作用提供参考。【方法】用生物信息学方法对枸杞SWEET基因(LbaSWEETs)进行全基因组鉴定,并用已发表的转录数据分析LbaSWEETs在果实发育时期的基因表达情况。【结果】枸杞SWEET基因家族共有37个成员,随机分布于10条染色体上,分别编码152~621个氨基酸,蛋白质分子质量为16.87~69.97 kD,等电点为4.96~9.86。亚细胞定位预测位于叶绿体或质膜,大多数含有7个跨膜螺旋。系统进化分析发现,37个LbaSWEETs蛋白可分为4个亚群,每个亚群的基因结构和保守基序组成相似。启动子元件分析表明:Lba-SWEETs基因启动子富含大量激素响应、逆境胁迫和生长发育响应元件。转录组数据和qRT-PCR分析表明:LbaSWEET9和LbaSWEET29基因表达量随果实成熟呈现显著增加。相关性分析结果表明,LbaSWEET9和LbaSWEET29基因表达量与果糖含量呈显著正相关。【结论】LbaSWEET9和LbaSWEET29基因是果糖积累的关键基因。

基于转录组信息的百合SWEET基因家族鉴定及表达特性分析

以东方百合品种‘西伯利亚’为试材,采用生物信息学方法,研究了百合SWEET基因家族成员编码蛋白的理化性质、二级结构、系统进化、保守结构域、Motif及基因表达模式,对百合SWEET基因家族成员进行鉴定,探究其在鳞茎发育过程中的作用,以期为该类基因生物学功能和百合地下茎生鳞茎发育机制的研究提供参考依据。结果表明:从转录组数据鉴定到了12个SWEET基因,所有家族成员都为稳定的疏水蛋白,且均含有MtN3_slv结构域,可划分为4个亚家族,不同成员在百合茎生鳞茎形成和进一步发育中差异表达。

中药辨证治疗Sweet综合征1例报道并文献复习

Sweet综合征又名急性发热性中性粒细胞增多性皮病,是一种与许多不同的基础疾病相关的皮肤病。其主要临床表现为发热、疼痛性红色斑块或结节,外周血白细胞和中性粒细胞增多,组织病理学特点为真皮中大量中性粒细胞浸润[1]。本病发病机制尚不明确,慢性感染和恶性肿瘤是最常见的发病诱因,临床表现差异很大,容易误诊,组织病理是诊断Sweet综合征的可靠依据。现报道1例以中药方剂内服为主治疗有干燥综合征基础合并Sweet综合征患者的过程并进行文献复习。

QTL Mapping for Partial Resistance to Southern Corn Rust Using RILs of Tropical Sweet Corn

Southern corn rust is one of destructive diseases in maize caused by Puccinia polysora Undrew. A mapping population of tropical sweet corn recombinant inbred lines (RILs) derived from a cross between hA9104 and hA9035 inbred lines were set up to detect quantitative trait loci (QTLs) involved in partial resistance to southern corn rust. Eighty nine RILs were used to evaluate resistance levels using nine-point relative scale (1-9) at Sweet Seeds, Suwan Farm, Thailand include combined analysis. A genetic linkage map was constructed with 157 SSR markers, with a total length of 2123.1 cM, covering 10 chromosomes. Broad-sense heritability of individual location ranged from 0.76 and 0.82 and combined across locations was 0.87. Multiple QTL mapping (MQM) was applied for the identification of the QTLs. Fifteen QTLs were detected on chromosome 1, 2, 5, 6, 9 and 10 in both locations and combined across locations. QTLs on chromosome 1, 5 and 6 were contributed by alleles of resistant parent hA9104 while others were contributed by alleles from the susceptible parent, hA9035. Phenotypic variance of each QTL explained ranged from 6.1% to 41.8% with a total of 69.8% - 81.9%. QTL on chromosome 1, 6 and 10 were stable QTLs detected in both locations.

Genome-wide association study of vitamin E in sweet corn kernels

Vitamin E,consisting of tocopherols and tocotrienols,serves as a lipid-soluble antioxidant in sweet corn kernels,providing nutrients to both plants and humans.Though the key genes involved in the vitamin E biosynthesis pathway have been identified in plants,the genetic architecture of vitamin E content in sweet corn kernels remains largely unclear.In the present study,an association panel of 204 inbred lines of sweet corn was constructed.Seven compounds of vitamin E were quantified in sweet corn kernels at 28 days after pollination.A total of 119 loci for vitamin E were identified using a genome-wide association study based on genotyping by sequencing,and a genetic network of vitamin E was constructed.Candidate genes identified were involved mainly in RNA regulation and protein metabolism.The known gene ZmVTE4,encodingγ-tocopherol methyltransferase,was significantly associated with four traits(α-tocopherol,α-tocotrienol,theα/γ-tocopherol ratio,and theα/γ-tocotrienol ratio).The effects of two causative markers on ZmVTE4 were validated by haplotype analysis.Finally,two elite cultivars(Yuetian 9 and Yuetian 22)with a 4.5-fold increase in the sum ofα-andγ-tocopherols were developed by marker-assisted selection,demonstrating the successful biofortification of sweet corn.Three genes(DAHPS,ADT2,and cmu2)involved in chorismate and tyrosine synthesis were significantly associated with theα/γ-tocotrienol ratio.These results shed light on the genetic architecture of vitamin E and may accelerate the nutritional improvement of sweet corn.

Genetic Model for Fresh-keeping Character in Sweet Corn

This study was conducted to investigate the genetic regularity of indexes related to freshness keeping and its molecular basis by acquiring 6 generations （P1, P2, F1, B1, B2 and F2） of an inbred line T3 with long freshness period × an inbred line T15 with short freshness period in sweet corn. The genetic analysis of the indexes was performed by major gene＋polygene mixed genetic model combined with the genetic analysis combining six generations.The results showed that the decreasing rate of the postharvest sugar content in the T3 was controlled by two pairs of additive-dominante-epistatic major genes＋additive-dominant polygenes; each segregating generation was affected by its major genes, the heritability of major genes and polygene in the B1 generation was 74.63% and 17.67%, respectively; the heritability of major gene and potygene in the B2 was 91.98% and 0,00%, respectively; and the heritability of major gene and polygene inthe F2 was 82.67%, and 12.93%, respectively.

Effects of Controlled-Release Fertilizers and Their Application Methods on Germination and Seedling Growth of Dent and Sweet Corns

Effects of controlled-release fertilizers (CRFs) (C-AS, polyolefin coated ammonium sulfate, 50-day-type; Dd-LP, polyolefincoated urea with dicyandiamide, 40-day-type; C-ANP, polyolefin coated ammonium nitrate phosphate, 40-day-type; andC-DAP, polyolefin coated diammonium acid phosphate, 40-day-type), ammonium sulphate and no fertilizer control, andtheir application methods (spot, band, surface and mixed) on germination and seedling development of sweet corn (Zeamays L.var. saccharata Sturt.) and dent corn (Zea mays L.var. indentata Sturt.) were investigated in a greenhouse. Underco-situs application (band and spot) of CRFs, there were no obvious differences in the germination speed and rate for bothdent corn and sweet corn relative to control. Mortality rates of sweet corn seedlings under co-situs application were highin experiment 1, but were very low in experiment 2, because the environmental conditions were different in the twoexperiments. That is, under lower temperature and weaker sunlight, young seedlings easily die due to high soil nutrientconcentration and slow growth speed of corn. Shoot weight of both dent and sweet corn did not greatly decrease inexperiment 1. In experiment 2, there were no significant differences in shoot and root weight of both corns between co-situs and surface or mixed application methods. However, with spot and band application of ammonium sulfate, shoot androot weight were significantly reduced. Soil EC and pH were considerably affected by co-situs application, especially atthe fertilizer application site. For both dent and sweet corn, EC in the 0-3 cm soil was significantly higher under co-situsapplication and surface application than that under mixed application, whereas in the 3-6 cm soil depth the situation wasreversed. Compared with control, mixed application of CRFs decreased soil pH slightly (0-3 cm depth) or greatly (3-6 cmdepth).

Relationships between changes of kernel nutritive components and seed vigor during development stages of F_1 seeds of sh_2 sweet corn

The changes of kernel nutritive components and seed vigor in F1 seeds of sh2 sweet corn during seed development stage were investigated and the relationships between them were analyzed by time series regression (TSR) analysis. The results show that total soluble sugar and reducing sugar contents gradually declined, while starch and soluble protein contents increased throughout the seed development stages. Germination percentage, energy of germination, germination index and vigor index gradually increased along with seed development and reached the highest levels at 38 d after pollination (DAP). The TSR showed that, during 14 to 42 DAP, total soluble sugar content was independent of the vigor parameters determined in present experiment, while the reducing sugar content had a significant effect on seed vigor. TSR equations between seed reducing sugar and seed vigor were also developed. There were negative correlations between the seed reducing sugar content and the germination percentage, energy of germination, germination index and vigor index, respectively. It is suggested that the seed germination, energy of germination, germination index and vigor index could be predicted by the content of reducing sugar in sweet corn seeds during seed development stages.

Seed Health Status of Sweet Corn (Zea mays L. saccharata Sturt) from Five Areas in China and Effect on Field Seedling Emergence

The health status of 18 sweet corn (Zea mays L. saccharata Sturt) hybrids classified to two types, collected from five areas in China, was examined by PDA method, and factors influencing seed health and relationships between seed health and field seedling emergence were studied. Seventeen fungal genera were isolated and Fusarium was the most frequently isolated. There were significant differences both in incidence of Fusarium and in percentage of infected seeds among 18 hybrids. Research also showed that significant and consistent differences both in seed-borne fungal taxa and in percentage of infected seeds existed between two types of sweet corn. Sugar enhanced corn is more slightly infected than super sweet corn both in fungal taxa (13 and 16, respectively) and in percentage of infected seeds (62.0 and 79.2%, respectively). There were also significant differences both in seed-borne fungal taxa and in percentage of infected seeds among five areas. Seeds from South China were most severely infected, for there were 14 fungal genera detected and the percentage of infected seeds was highly 99.1% while those from Northwest China were slightly infected, for there were 10 fungal genera detected and the percentage of infected seeds was only 14.3%. Further research showed that there were significant negative correlations both between incidence of Fusarium and percentage of field seedling emergence and between percentage of infected seeds and percentage of field seedling emergence. Percentage of field seedling emergence could be estimated by regression equations built by regression analysis.

Effect of Sweet Corn Straw Returning to the Field on Soil Fertility, Yield and Benefit

It is an important way for realizing sustainable development of sweet corn production to stabilize and improve soil fertility of cultivated land in sweet corn production region.Through the test of sweet corn straw directly returning to the field after 6seasons for 3years,the results showed that continuous single application of chemical fertilizer is not conducive to the stability of soil fertility and yield improvement,and implementation of straw returning could receive fertility,improve soil acidic conditions,and enhance the yield of sweet corn.Compared with before the test,the single application of chemical fertilizer increased soil available phosphorus,while the contents of soil organic matter,available nitrogen and available potassium decreased by 1.08,1.18 and 2.47mg/kg respectively,and the soil pH decreased by 0.15.Under the same fertilizer conditions,organic matter contents of single and double-season straw returning increased by 0.71 and 1.29g/kg,available nitrogen increased by 17.15 and 28.27mg/kg,available phosphorus increased by 0.96 and 1.73mg/kg,available potassium increased by 2.41 and 5.92mg/kg,the soil pH increased by 0.16 and 0.2.Compared with the single application of chemical fertilizer,the average yields of single and double-season straw returning increased by 7.5%and 11.8%,and their average income increased by 87.3and 117.1yuan of per mu(667m^2)respectively.

The Comparison of Sugar Components in the Developing Grains of Sweet Corn and Normal Corn

The sugar components and their dynamic variation in the developing grains of sweet corn(Zea mays L. seccharata Sturt)and normal corn (Zea mays L. indentata Sturt) were compared. There are WSP (water-soluble polysaccharides), sucrose, fructose, glucose, mannitol and sorbitol in both sweet corn and normal corn, but no maltose. Two components with different degrees of polymerization (D. P. N) were detected in the sweet corn; only one of them was detected in the normal corn 20 days after pollination. With the development of grains, the total soluble sugar content(TSS)in sweet corn increased, but in normal corn it decreased. The dynamic variation of WSP, sucrose, glucose, fructose, mannitol and sorbitol in sweet and normal corn grains are different. The contents of sugar components in the sweet corn grains are higher than that in the normal corn. Sweet corn accumulates less starch than normal corn.

联合化疗治疗原发性胃弥漫大B细胞淋巴瘤合并Sweet综合征1例并文献复习

非霍奇金淋巴瘤(non-Hodgkin lymphoma,NHL)是临床常见的肿瘤类型,临床表现多样,确诊依赖组织活检,根据病灶起源可以分为结内和结外淋巴瘤。原发性胃肠淋巴瘤是结外淋巴瘤的常见部位,可以累及胃、小肠、结肠等,其中约50%~60%发生在胃部,病理类型以黏膜相关淋巴组织淋巴瘤和弥漫大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)为主[1~3]。

Leaf Turgor Potential, Plant Growth and Photosynthesis in Organically Fertilized Sweet Corn

A greenhouse pot experiment was conducted using a complete random design with six replications. A pressure-volume curve analysis was employed to study the effects of organic fertilizers on plant water relations in sweet corn (Zea mays L. cv. Honey-bantam) in terms of leaf osmotic concentration (Cs), osmotic potentials at full turgid status (πFT) and at incipient plasmolysis (πIP), and of symplastic (ζsym) and apoplastic (ζapo) fractions in the tissue water compartment in relation to photosynthetic capacity (Pc) and dry mass accumulation. At the seedling stage (day 15), plants with chemical fertilizer treatments showed lower πFT, πIP and ζapo and higher Cs, ζsym and PC than those with organic fertilizer treatments. Compared to PC and relative growth, where values from day 15 to day 75 were first lower for organic treatments and then higher, ζsym and Cs values were similar, while πFT and πIP were opposite being higher then lower. Dry mass production with organic fertilizer was higher than or close to the chemical fertilizer treatments in the later growth stage (day 75), though dry mass production with chemical fertilizers was much higher in the early and middle growing stages (days 15 and 45). Increased photosynthesis and dry mass production in later growth stages due to organic fertilizers were associated with increased osmotic concentration in the tissue and the symplastic fraction of the tissue water compartment. These might favor stomatal opening and biochemical activities.

猕猴桃AcSWEET基因家族的鉴定与表达分析

SWEET(Sugars will eventually be exported transporters)是近年来在植物中发现的一组糖转运蛋白,在植物生长、发育和非生物及生物胁迫响应等多种生理过程中发挥着重要作用。本研究利用生物信息学方法对猕猴桃(Actinidia chinensis Planch.)AcSWEET基因家族进行了鉴定,共获得29个AcSWEET基因,并对其氨基酸数量、相对分子量、等电点、不稳定系数、亚细胞定位、亲水指数进行了分析。结果显示:29个基因编码的氨基酸数目为680~906个;分子量范围为7.531~101.266 kDa,等电点在6.95~9.90,多数蛋白为定位于细胞膜的疏水性蛋白,具有1~2个MtN3结构域或PQ-loop结构域。此外,AcSWEET基因的外显子数量在4~6个,系统进化分析结果表明猕猴桃AcSWEET基因家族被分为4个亚族,同一亚族基因具有相似的内含子、外显子以及保守基序。表达模式分析结果表明,这些基因在果实不同发育时期具有表达特异性。推测AcSWEET26、AcSWEET7、AcSWEET15和AcSWEET13可能参与猕猴桃的蔗糖转运和积累。

CORN评估量表在预防胸外科术中获得性压力性损伤中的应用研究

目的探讨胸外科手术患者根据CORN量表及时采取护理措施,预防术中获得性压力性损伤的效果。方法选择2023年1—6月呼和浩特市某三甲医院胸外科侧卧位手术患者70例作为研究对象,根据入院先后顺序将2023年1—3月就诊的患者作为对照组(35例),将2023年4—6月就诊的患者作为实验组(35例)。对照组采用Braden量表进行评估,实验组采用CORN量表进行评估。为所有患者提供基本防护措施,根据两种量表评分对中风险及高风险患者采取针对性护理措施。在术后即刻及术后24 h、48 h和72 h评估皮肤情况。比较两组患者术中获得性压力性损伤发生率、住院天数、手术医生对手术室专科护士配合满意度评分和手术室护士预防术中获得性压力性损伤专业能力。结果实验组术中获得性压力性损伤发生率低于对照组,差异有统计学意义(P<0.05);实验组住院天数少于对照组,差异有统计学意义(P<0.05);实验组手术医生对手术室专科护士配合满意度评分高于对照组,差异有统计学意义(P<0.05);实验组手术室护士预防术中获得性压力性损伤专业能力高于对照组,差异有统计学意义(P<0.05)。结论CORN量表应用于胸外科侧卧位手术患者可识别中高风险人群,提前进行护理干预,可降低术中获得性压力性损伤的发生率,缩短患者住院时间,提高手术医生对手术室专科护士配合满意度评分,提高手术室护士预防术中获得性压力性损伤专业能力。

植物SWEET基因及其糖转运功能研究进展

SWEET(sugars will eventually be exported transporter)是一类介导蔗糖或己糖通过顺浓度梯度被动扩散跨细胞膜转运的新型糖转运蛋白。植物SWEET蛋白包括7个跨膜结构域,其中包含2个MtN3/Saliva结构域,可分为4个进化分支。SWEET转运蛋白在多种生理和生化过程中发挥着关键作用,包括韧皮部装载、激素运输、营养和生殖生长等。结合当前SWEET转运蛋白的研究进展,重点总结了SWEET的发现、蛋白结构及其在糖转运中的生物学功能,指出目前植物SWEET基因研究面临的问题,并对未来SWEET蛋白的研究重点进行了展望:1)探究SWEET蛋白的底物识别机制;2)挖掘提高作物产量和品质的关键SWEET基因;3)利用SWEET基因编辑和磷酸化等策略改良作物产量和品质。