Background The availability of potassium is one of the main environmental factors for modifying the plasticity of root architecture. Many potassium channels and transporters are involved in regulating primary root growth in response to low potassium stress. NRT1.5/NPF7.3 transporter is a NO 3 − /H + and K + /H + cotransporter, and participates in NO 3 − and K + translocation from the roots to the shoots. However, the underlying mechanism of NRT1.5-regulated primary root growth under low potassium stress is unclear. Results We show that NRT1.5/NPF7.3 inhibited primary root growth under low potassium conditions by regulating the accumulation of PIN2 protein and auxin levels. Under low potassium conditions, the mutants nrt1.5 and lks2 exhibited longer primary roots, longer meristem regions and elongation zones of primary roots, and more cell activity in the meristem region compared to WT plants, revealing the involvement of NRT1.5 in LK (low potassium)-inhibition primary root growth. In addition, exogenous auxin (IAA), auxin analogue (NAA, 2.4-D) or auxin precursor (IBA) promoted the primary root growth of WT and the complementation line NRT1.5 COM plants. In addition, the application of NPA inhibited the primary root growth of the nrt1.5 and lks2 mutants. Auxin accumulation was higher in the root tip of nrt1.5 plants than in WT plants, indicating that NRT1.5 regulates root growth inhibition by regulating auxin distribution. Furthermore, PIN2 was degraded more quickly in nrt1.5 plants under LK stress. Conclusions Our findings reveal that NRT1.5 inhibits primary root growth by modulating the auxin level in the root tip via the degradation of PIN2.

为了检验内生菌荧光假单胞菌DLJ1和蜡状芽胞杆菌SZ5的促生与提高植株对南方根结线虫的防治效果,确定合适的菌剂接种方式,并分析其机制,本文以杀线剂阿维菌素为对照,比较了不同接菌方式下DLJ1和SZ5对辣椒植株在南方根结线虫胁迫下的抗性以及对产量品质的影响.结果 证实DLJ1在种子萌发期的一次接菌与萌发期与田间的5次接菌处理均可使根系根结数减少70％以上,使植株对南方根结线虫的抗性升至高抗级别,辣椒产量提高超过150％;DLJ1一次接菌处理组的果型最大、Vc与可溶性蛋白含量最高.SZ5萌发期一次处理根结数降低40％,植株对南方根结线虫表现为中抗,产量提高60％以上;SZ5多次接菌处理根结数只能降低27％,产量仅提高6％左右.阿维菌素处理的效果介于DLJ1和SZ5之间,可降低植株根结数45 ％,提高产量49％左右.分析其机理发现,两菌剂处理均可通过提高植株的POD酶活性和总酚含量,降低O2产生速率和MDA积累,提高光合色素含量等来促进植物生长,通过提高几丁质酶活性来提高植株对线虫的抗性.总之,只需要在辣椒种子萌发期进行一次DLJ1接菌处理,即可使植株获得稳定而显著的促生和防治南方根结线虫双重效果,提示DLJ1菌在农业生产上的应用前景广阔.

Chemical fertilizer (CF)-oversupplied soils in intensive agricultural systems are typically abandoned due to loss of fertility and productivity. In this study, we investigated the potential of organic-mineral fertilizer (OMF), produced by a combination of organic matter, potassium (K)-feldspar powder and microbial fermentation, to alleviate the same in purslane cultivation. A gradient dose of OMF was applied to CF-oversupplied soils and purslane was grown in it and the alterations in soil physic-chemical parameters and enzyme activities along with purslane nutritional traits were analysed after 80 days. From the results, soil with excessive CF exhibited a sharp decrease in pH and increased electrical conductivity (EC); further, the activities of enzymes, such as urease, alkaline phosphatase and carbonic anhydrase (CA), showed an abrupt decrease. When a gradient dose of OMF (67, 134 and 200 g kg−1 soil based on the previous research in the lab) was applied to the CF-oversupplied soil, their available K content was significantly higher than the CF-oversupplied treatment and control. Additionally, the contents of total carbon and active organic carbon (AOC) were highest in treatment group OMF3 + CF (200 g of OMF kg−1 soil). The nutritive contents of purslane, such as soluble sugar and total flavonoids, and relative contents of ω-3 polyunsaturated fatty acid (PUFA) etc. showed a significant increase when compared with control, while the anti-nutritive compounds, such as nitrates and soluble oxalic acid, decreased. The positive effects on the soil quality traits and purslane growth and nutritive quality suggest the OMF treatment might be a promising approach for sustainable crop production and soil remediation in CF-oversupplied soil.

整合现代教学手段,提高教学效率和学生综合素质是我们的目标.教学实践中,将植物生理学课程教学体系分成线上、线下两个环节.线上环节主要通过"在线课程"完成,线下环节则以"翻转课堂"形式在智慧教室展开.通过完成"在线课程"中的教学视频和在线测试完成基础知识学习;通过思维导图作业促进学生将零散知识串成体系、并提出问题;通过"翻转课堂"中的层层问题提出与讨论,深化对基础知识及其应用的理解;通过文献翻转,在提高学生综合能力的同时,进一步深化理解如何运用基础知识;通过过程性考核促进学生重视每个环节.几年的实践结果表明,将在线课程、思维导图、智慧教室和在线沟通等多种现代教育手段整合运用到层层推进的教学中,在高质量完成教学的同时,还可以提高教学效率,促进师生共同发展.

为拓展DLJ1和SZ5菌剂的应用范围,并初步探讨其作用机制,以油菜和小麦种子为试材,分别在种子萌发期和萌发后进行培养皿试验,以无菌水处理为对照,分析了NA培养液、SZ5菌悬液、DLJ1菌悬液、SZ5发酵液和DLJ1发酵液处理对油菜和小麦种子萌发及幼苗生长的影响.结果表明:萌发期2个菌剂的菌悬液处理均对油菜和小麦种子萌发无显著影响,而NA培养液和发酵液处理显著延缓了种子萌发.菌剂处理时间不同,对萌发后种子及幼苗生长的影响也不一样.萌发期的DLJ1发酵液处理可显著促进油菜萌发苗根、茎、叶的生长以及小麦萌发苗根系的伸长,其促生效果优于其菌悬液处理和SZ5发酵液处理;萌发后的菌剂处理中仅DLJ1菌悬液可显著促进小麦幼苗根系伸长,整体促生效果相对较弱.DLJ1分泌的ACC脱氨酶活性较高以及具有产铁载体能力,可能是其促生效果优于SZ5处理的原因.本研究结果预示DLJ1菌剂在油菜生产上有一定的应用前景,建议在萌发期进行DLJ1菌剂处理效果可能更好.

本文以两株产ACC脱氨酶的内生菌蜡状芽孢杆菌SZ5和荧光假单胞菌DLJ1为材料,探讨其在辣椒促生和预防线虫病害方面的作用.结果显示,虽然两菌剂处理不能促进种子萌发,但对幼苗生长有短暂促进作用;促生作用消失后,植株体内次生代谢物质含量和抗氧化酶活性仍高于对照,DLJ1组高于SZ5组.挑战接种南方根结线虫后,接菌组植物体内的POD等酶活性以及总黄酮等物质含量的提高幅度高于对照.菌剂处理降低了植株染病率和染病程度,提高了辣椒产量和品质;萌发期一次处理效果优于后期的多次处理,DLJ1的处理效果优于SZ5.总之,DLJ1在辣椒种子萌发期一次接菌就可以有效促进辣椒生长,提高植株对南方根结线虫的抗性,提高辣椒产量.该作用可能与萌发期菌株的有效定植、生长期的抗氧化能力的维持与高效反应,以及有效降低乙烯产量有关.

Increasingly, poor soils are used for plant cultivation involving chemical fertilizer (CF) usage which in turn lowers soil quality. To improve the quality of poor soils, promote plant growth, and reduce CF use, bio-organic-mineral fertilizer (BF) was introduced to poor soil to examine its effects on both soil and plants. Organic fertilizer (OF), CF, and mineral powder (MP) were applied as controls. When cotreating water spinach with fertilizer, the soil quality was improved with the increased doses of BF, OF, and MP. The BF treatment produced the most pronounced improvement. Applying CF reduced the soil quality. Under the CF treatment the largest plant-growth-promoting effect was observed within 30 d, whereas plants treated with BF showed the most favorable growth after 50 d. Moreover, for BF, plants' nutritional quality was also higher, particularly in the long term. When poor soil was treated with fertilizer without plants, the soil quality changed as in the previous treatment; however, the change in this treatment was more pronounced and the remaining available elements in soil were higher, particularly in the case of CF treatment. These results indicate that BF treatment without CF can be applied to improve the quality of poor soil, and meanwhile promote plant growth and quality.

马齿苋种子为小种子,野生型的种子更小,千粒重仅为栽培型的1/6;两者种皮均具纹饰,野生型种子的正面纹饰和侧面瘤状突起较栽培型种子的更加规则整齐.根据种子大小和表面纹饰形态比对Danin的检索表,将本研究涉及的野生型马齿苋归为Portulaca granulatostellulata (Poelln.)C.Ricceri et P.V.Arrigoni亚种(4 N=36),栽培型马齿苋归到Portulaca edulis Danin & Bagella亚种(6 N=54).马齿苋种子萌发迅速,但栽培型种子萌发更加迅速整齐;野生型植株匍匐生长,主侧枝区分不明显,叶、花、果实和种子均较栽培型小;栽培型植株直立,主侧枝区分明显;两者均可行有性生殖,且均可闭花传粉受精,但栽培型植株单株花苞数少,每一花苞内种子数少,显示其有性生殖能力相对较弱.野生型马齿苋种子更小、萌发不整齐、种子量大等特性提示其在形成地下种子库、躲避灾难性逆境的能力更强,更适于生态修复;而栽培型马齿苋的种子萌发迅速整齐、株型直立等特性更有利于其迅速建群,并在农业生产上应有更大的发展空间.

海州地区历史悠久,文化底蕴深厚,山海景观秀丽,风土人情浓郁,这些风物为李汝珍创作《镜花缘》所取资.作为一部博物体小说,《镜花缘》蕴含了丰富的茶文化内容,体现作者的茶文化观.

中国的茶文化博大精深，源远流长。高校开展茶文化教育对当代大学生有修身、俭廉、和谐、养生、保健的积极作用。饮水思源，激发大学生奋发向上，为我国茶产业的可持续发展培养生力军，推动茶文化发展。

In recent years, many researchers have explored various possible ways to slow down the increase in atmospheric CO2 concentration as this process poses a serious threat to mankind's survival. Mineral weathering is one possible way. Silicate weathering, for example, causes net carbon sequestration and carbonate weathering occurs relatively rapidly. In this study, dolomite and K-feldspar were added to soil to investigate if these minerals can increase carbon sequestration and also improve the available potassium content. The carbon content of amaranth, the organic and inorganic carbon content of the soil, two kinds of enzymes (polyphenol oxidase and urease), and the available potassium content were all tested. The experimental results show that the minerals accelerate the fixation of organic and inorganic carbon in the soil and also promote amaranth growth. Moreover, the available potassium content was increased when K-feldspar was added. Taken together, adding moderate amounts of carbonate and silicate minerals into the soil is found to be an attemptable way of accelerating CO2 fixation and improving the potassium content of soil.

为了提高马齿苋的组培效率,解决马齿苋出愈时间迟、愈伤组织诱导率不高、愈伤组织诱导需要使用2,4-D、不定芽增殖来源有限等问题,根据马齿苋的最适生长条件,将组织培养环境调整为温度(30±1)℃、全光照,并从无菌苗上直接取材进行外植体培养.结果表明:种子在高温、全光照条件下萌发快,且无菌苗长势好.取材于无菌苗上的根、茎和叶均可以在不添加2,4-D的MS培养基中脱分化形成愈伤组织,且茎在MS+NAA 1.0 mg/L+6-BA 1.0 mg/L培养基中、叶在MS+NAA 1.5 mg/L+6-BA 0.5～1.5 mg/L培养基中的初始出愈时间均提前至4d,且诱导率均达到100％,愈伤组织长势旺盛.带腋芽的茎段在MS+NAA 0.1 mg/L+6-BA 5.0 mg/L培养基中可以直接分化出大量不定芽,增殖率达10.5.在最适光温环境下,马齿苋外植体出愈迅速,愈伤组织诱导率和不定芽增殖率大幅度提高.

With the large-scale development of aquaculture industry,a large number of roxarsone( ROX,a kind of veterinary drug)-containing manure are being applied to vegetables as organic fertilizer. Whether ROX's large application will reduce the yield and quality of vegetables or not is noteworthy. The common leafy vegetable, Amaranthus mangostanus,was selected in this paper to suspect these effects. Results showed that ROX treatment inhibited the elongation of radicles and root systems which led to the decrease of the height,leaf area and biomass of seedlings. The results of chlorophyll fluorescence parameters( Fv / F0 and Fv / Fm) implied that ROX could damage the PSII structure and function of A. mangostanus leaves,which led to a decrease in photosynthetic capacity. Contents of reductive ascorbic acid( As A),glutathione( GSH) and anthocyanin increased with the increase of ROX,While contents of inorganic nutrient,soluble sugar and soluble protein were relatively stable. ROX treatment promoted the accumulation of As and nitrate in A. mangostanus. The As content in the edible parts was beyond the arsenic content limits of food and vegetable in WHO,FAO and China,and the nitrate content had reached moderate and severe pollution level. Given all that,veterinary drug ROX residue in the soil,will not only inhibit seed germination and seedling growth,reduce vegetables' yield,but also may reduce the vegetables' quality,improve human cancer risk through the accumulation of arsenic and nitrate.

以不同剂量 NaN3处理马齿苋种子，从种子萌发、植株生长、光合性能的角度确定最适 NaN3处理剂量，并分析以叶绿素荧光动力学方法辅助筛选的可行性。结果表明，1．0 mmol／L NaN3处理8 h 或0．5 mmol／L NaN3处理12 h均可显著提高种子萌发率和萌发质量，而更高浓度、更长时间的处理则使萌发率和萌发质量逐渐下降；根据长势初筛后的各处理组种子萌发苗，其株高均高于对照或与对照相当，单叶面积（2．0 mmol／L NaN38 h 处理组除外）则低于对照；各处理组叶片 PSⅡ的潜在和实际光化学效率普遍高于对照（其中2．0 mmol／L NaN38 h 处理组最高），但除2．0 mmol／L NaN38 h 处理组外，各组对高光强的抵御能力，特别是快速保护能力均有所下降。2．0 mmol／L NaN38 h处理组中马齿苋种子获得植株的株型最高、单叶面积最大、潜在和实际光化学活性最强、抵御强光胁迫能力最强。可见，以2．0 mmol／L NaN3处理8 h 是马齿苋种子的最适处理条件，而采用叶绿素荧光动力学分析技术可实现对当代植株光合能力、高光强抗性的无损伤分析，极有利于提高筛选效率。

To explore the difference of C 4 and C 3 photosynthetic pathways in responding to high salinity and its potential role in determining vegetation zonation in coastal saltmarshes, two Poaceous halophytes, C 4 Spartina alterniflora and C 3 Phragmites australis , were studied with different salinities. The results showed that proper salinities were required for both species to maintain optimal photosynthesis. The maximal net assimilation rates of S. alterniflora and P. australis appeared with 400 and 100 mmol L −1 NaCl, respectively. Both species exhibited similar responses of stomatal conductance towards the set salinities, and chlorophyll contents in P. australis were even promoted by 100–400 mmol L −1 NaCl. Although no significant changes in the maximal quantum yield of photosystem II were found in either species treated by NaCl, instant quantum yield of photosystem II of P. australis was significantly decreased, whereas that of S. alterniflora increased. We suggest that the zonation between S. alterniflora and P. australis is not exclusively caused by the CO 2 -concentrating mechanism of the C 4 pathway and stomatal conductance is not a restricting factor for either species. It might be that the electron transfer from photosystem II and the energy use efficiency being limited in the C 3 P. australis grown under high salinity.

With the increase of focus on food safety,copper agents which have the characteristics of pollution-free,no re?sistance etc. are widely used in organic agricultural production. Whether the extensive application of copper agents will bring influence on the yield and quality of foods or not is noteworthy. To inspect this influence,the changes of seed ger?mination,seedling growth and vegetable quality of Ipomoea aquatic under CuSO4 processing will be assayed in this pa?per.Results showed that CuSO4 treatment not over 1 mM had no obvious effect on seed germination rate,but would re?duce seed germination quality. CuSO4 treatment not over 9 mM had no obvious effect on seedling growth,photosynthesis, yield and nutrient content. CuSO4 treatment would increase copper accumulation in I. aquatic seedlings,and copper would accumulate preferentially in roots. Copper content in leaves and stems in the treated I. aquatic seedlings would not exceed the national standard,but it would exceed the standard in roots when CuSO4 was not less than 3 mM. CuSO4 treatment would reduce the nitrate reductase activities which led to the nitrate accumulation to the severe pollution level in I. aquatic seedlings. This would reduce the vegetable quality and enhance the human cancer risk.

Abelmoschus manihot( L.) Medic is an annual wild herbaceous plant which belongs to Abelmoschus Medus,Malvaceae. The seeds are grayish wide renal globes with the length of( 0. 435 ± 0. 039) cm,width of( 0. 414 ± 0. 035) cm and thousand grain weight of( 20. 521 ± 0. 03) g. The seeds need 7 h to imbibe fully in25 ℃ water. The just collected seeds can germinate directly,meaning the seeds have no deep dormancy. The seeds germinate well only under 30 ℃ and alternating light and dark,suggesting high temperature and light are the essential conditions for the seed germination. The seeds show the highest germination rate only under the conditions without salt and osmotic stress,and their germination indices decrease gradually with the increase of Na Cl and PEG stress. These suggest that the germination of A. manihot seeds is highly sensitive to salt stress and osmotic stress. The highest germination rate in this paper is only 58%,suggesting the germination rate of A. manihot seeds is not high. So,in practice the seeds are suggested to germinate first to improve their germination rate under the condition with appropriate temperature,light and non-stress; then the seedlings can be hardened under stress to improve their resistance.

1992年世界卫生组织提出合理膳食、适量运动、戒烟限酒、心理平衡的健康理念,成为现代健康四大基石.故从饮食、运动、烟酒、心理4个方面分析现代健康基石与《黄帝内经》养生的关系,阐述《黄帝内经》食饮有节、起居有常、不妄作劳、形与神俱的养生智慧.

为探索籼粳杂交水稻花药培养再生体系,以籼稻‘扎西玛’和粳稻‘南粳46’籼粳杂交F1花药为外植体,分别从低温预处理时间、基本诱导培养基种类、蔗糖质量浓度及不同激素配比方面研究花药愈伤组织诱导,并将诱导出的愈伤组织进行分化成苗,以期构建籼粳地理远源杂交水稻花药培养再生体系.结果表明,4℃处理2～5 d的花药,其愈伤组织诱导率较高,与未处理和低温处理6～10 d相比达到显著水平;添加蔗糖质量浓度为60g·L-1,以N6或M8为基本培养基均可以获得较高的诱导率;以M8为基本培养基,添加2,4-D 2 mg·L-1和KT 0.3 mg· L-1诱导水稻愈伤组织出愈率可高达32.14％;以MS为基本培养基,激素组合为KT 2 mg ·L-1和ABA 3 mg· L-1分化培养基,其愈伤组织成苗率可达50％,其中绿苗分化率达4.55％.

陆羽《茶经》挖掘和推广了茶这种资源植物成为可持续发展的最佳物种,使全世界1/3的人口受益.推动茶文化发展超越了民族与宗教界限,发展“茶”成为“万病之药”.现阶段,更需要在高效综合利用、发展多样化茶品、提高茶叶质量等方面发展茶产业与《茶经》.