Thiamine (vitamin B1) seed treatment enhances germination and seedling growth of bean (Phaseolus vulgaris L.) exposed to soaking injury

Seed treatment with thiamine mononitrate significantly increased germination rate of bean (Phasenius vulgaris L.) seedlings germinated at high soil moisture levels and low night-temperature (5° C). Beneficial effects of thiamine applications on germination were also observed in soil-free germination tests when the seeds were submerged in water for 1–4 d at 18°C. Optimum response was achieved at thiamine concentrations of 3 mM, applied during the first 24 h of imbibition. As an early response to the thiamine treatment, vital staining with triphenyltetrazolium chloride revealed a lower proportion of damaged tissue of the embryonic axes. In later stages of seedling development, thiamine seed treatment resulted in a lower proportion of abnormal seedlings with malformations of the shoot apex and of the primary leaves. The beneficial effect of thiamine was more pronounced when the temperature during submergence was kept at 25° C compared to 5° C. There was no response to thiamine applications when the germinating seeds were exposed to low temperature treatments only. The thiamine effect could be mimicked by raising the osmotic potential of the incubation medium, indicating a relationship to soaking injuries. The results suggest that normal seedling development may be impaired by thiamine deficiency in the embryonic tissue induced by soaking injury, whereas low temperatures are not involved as a stress-factor.     

钼酸钠浸种对花生种子萌芽及幼苗生长的影响

本文研究不同浓度钼酸钠浸种对花生种子萌发和幼苗生长的影响。试验结果表明,一定浓度的钼酸钠溶液浸种,对花生种子萌发具有促进作用,可以提高花生种子的发芽率,促进种子胚根的生长。在花生幼苗生长阶段,它能增加叶片叶绿素含量和可溶性蛋白质含量,提高了过氧化氢酶活性和硝酸还原酶活性。实验结果显示,钼酸钠溶液浸种是促进花生种子萌发和幼苗植株生长的重要措施。     

DIFFERENTIAL GERMINATION AND DEVELOPMENTAL RESPONSES OF BLETIA PURPUREA (ORCHIDACEAE) TO MANNITOL AND SORBITOL IN THE PRESENCE OF SUCROSE AND FRUCTOSE

Orchid seeds are energy-limited at dispersal and require infection by fungi in situ or an exogenous carbohydrate source when grown in vitro. While they are able to utilize a wide range of carbohydrates, polyols (sugar alcohols) are not known to enhance germination and early seedling development. In this study, we examined whether two polyols, mannitol and sorbitol, are inhibitory to germination and development or simply not utilized during germination using Bletia purpurea as a model orchid. When seeds were cultured with germination-promoting sugars (sucrose and fructose), sorbitol had little or no effect on germination and slightly inhibited seedling development at high molarities. Seeds cultured in the presence of mannitol and sucrose or fructose at 1 and 10 mmol exhibited enhanced germination, seedling development and rhizoid production. Mannitol alone did not enhance germination over control. We hypothesize that mannitol is taken up by Bletia purpurea embryos, leading to reduced osmotic stress and allowing for enhanced production of dehydration-sensitive rhizoids.     

外源物质浸种对黄瓜陈种子萌发效应的影响

为提高老化种子的生活力和利用率，有效利用黄瓜种子，给黄瓜陈种子在生产中的应用提供数据支撑。以贮存11 a的黄瓜品种甘丰11号种子为材料，采用培养皿发芽法，研究不同外源物质CaCl2、KH2PO4、KNO3、SA、ZnSO4浸种对黄瓜陈种子萌发的影响。结果表明，5种不同浓度的药剂均能不同程度提高黄瓜种子的发芽率，以0.175 mg/L的CaCl2溶液浸种对黄瓜陈种子萌发的促进作用最显著，其发芽率为(91.67±1.66)%、发芽势为(87.90±1.40)%、发芽指数为53.63±2.15，较对照只加入清水处理分别提高31.58%、56.96%、69.37%，各处理间差异达到显著水平(P ＜ 0.05)。生产中可以选用0.175 mg/L的CaCl2溶液浸泡处理黄瓜陈种子。     

复硝酚钠对低温下黄瓜种子萌发和幼苗耐寒性的影响

为缓解低温胁迫对黄瓜(Cucumis sativus L.)幼苗的伤害,以黄瓜中农106为试验材料,研究不同浓度复硝酚钠(CSN)浸种对低温胁迫下黄瓜种子萌发及萌发后生长的影响,以及CSN灌根处理对黄瓜幼苗壮苗效果及幼苗耐寒性的影响。结果表明,适宜浓度的CSN浸种能显著提高低温胁迫下黄瓜种子的发芽率、发芽势、发芽指数、活力指数、侧根数和鲜重,以50 mg·L^-1浓度效果最佳。在黄瓜育苗过程中,100 mg·L^-1的CSN灌根处理能显著提高穴盘苗质量和壮苗指数,低温胁迫下CSN通过促进矿质元素吸收,提高幼苗叶绿素含量、净光合速率、根系活力、可溶性蛋白含量和抗氧化酶活性,提高生长素(IAA)和油菜素内酯(BR)含量,降低活性氧和丙二醛(MDA)含量以提高幼苗的耐寒性。本研究为培育黄瓜壮苗和提高黄瓜幼苗耐寒性提供了新方法,也为复硝酚钠在设施蔬菜上的应用提供了技术支持。     

外源GA_3浸种处理促进火龙果种子发芽

火龙果种子播种育苗存在着种子发芽慢、发芽不整齐、发芽率低及幼苗细弱等问题。为了探讨提高火龙果种子发芽速度、发芽率和种子活力的方法,本试验以白肉火龙果（Hylocereus undatus Brit.t ＆ Rose）种子为材料,采用4个不同浓度（100mg/L,200mg/L,300mg/L和400mg/L）外源GA3对种子进行浸种处理,在适宜的光、温、水、气条件下催芽,通过对种子发芽势、发芽率、发芽指数、幼苗鲜重和活力指数的测定,研究不同浓度外源GA3浸种处理对火龙果种子发芽的影响,不处理为对照。结果表明,不同浓度外源GA3浸种处理对火龙果种子的发芽势、发芽率和种子活力均有明显的促进作用,其中400mg/L处理效果最好,300mg/L处理次之,再次是200mg/L、100mg/L,对照最差。本文的研究结果,将为火龙果种子播种育苗及育种工作提供科学理论依据。     

Promoting deep-sowing germinability of corn (Zea mays) by seed soaking with gibberellic acid

The effects of seed soaking with gibberellic acid (GA₃) on germinability of conventional corn variety ‘Nongda 108’ and super sweet corn variety ‘Chaotian 3’ were investigated under deep-sowing condition. GA₃ soaking significantly improved seed germination and mesocotyl elongation of both varieties under 10 or 6 cm sowing depth. The most significant promotion occurred at 0.175 g L^?1 GA₃ in ‘Nongda 108’ and 0.035 g L^?1 GA₃ in ‘Chaotian 3’. To further illustrate the physiological explanations, seed respiration was estimated from dehydrogenase activity test and oxygen-sensing test. Dehydrogenase activities of both varieties were dramatically promoted after GA₃ soaking. Compared with water soaking, the dehydrogenase activity in 0.175 g L^?1 GA₃-soaked seeds of ‘Nongda 108’ and 0.035 g L^?1 GA₃-soaked ones of ‘Chaotian 3’ was increased by 15.4% and 78.8%, respectively. Oxygen-sensing test showed that increased metabolism time (IMT) critical oxygen pressure (COP) and relative germination time (RGT) were decreased while oxygen metabolism rate (OMR) and relative germination rate (RGR) were increased in GA₃-soaked seeds, suggesting that exogenous GA-accelerated seed respiration. Our results suggested that seed soaking with exogenous GA₃ was a simple and practicable method to improve deep-sowing tolerance during corn seed germination, and the significant promotions were attributed to vigorous respiratory metabolism.     

SODIUM CHLORIDE PRIMING IMPROVES SALINITY RESPONSE OF TOMATO AT SEEDLING STAGE

We aimed to investigate whether sodium chloride seed priming and irrigation at seedling stage enhance response of 5-leaf stage tomato plants (Lycopersium esculentum Mill.) to high salt stress. Three experimental groups were as; non-primed seeds, seeds primed with 0.05M sodium chloride (NaCl), and seeds primed and irrigated with 0.05M NaCl starting from sowing to salt stress application. Sodium chloride solutions (0.1M, 0.2M, 0.4M, and 0.6M) were added to cups under pots in every 2 days for 10 days to treatment groups. Control groups were irrigated with distilled water at the same time intervals. At least two experimental setups contained at least four plants, and two samplings of leaf and root tissues were performed for analysis of each plant to evaluate changes in pigment and proline contents, lipid peroxidation and electrolyte leakage levels, and ascorbate peroxidase and catalase activity. Priming reduced mean germination time, and increased final germination percentage together with energy of germination. Increased root and hypocotyl lengths as well as increases in fresh weights supported enhanced seedling vigor. Considering growth and stress parameters such as chlorophyll content, chlorophyll to carotenoid ratios, and lipid peroxidation and electrolyte leakage were less affected in primed plants. Moreover, improvement of the accumulation of osmoregulating defense molecules, such as proline and anthocyanin, and of the inductions of the antioxidative enzyme system points out to higher adaptive response of these plants against deleterious effects of salt.     

生长延缓剂对华北边坡绿化3种草本植物种子发芽的影响

草本植物可以稳定公路、铁路和矿山等工程建设遗留的大量裸露边坡,并改善其生态环境,而以灌草型植物为目标群落的边坡绿化中,草本种子比灌木种子萌发和生长快、竞争性强,开展植物生长延缓剂的研究,以抑制草本种子萌发和生长.以华北地区的常用的沙打旺、紫花苜蓿和高羊茅为试材,探索不同浓度的矮壮素、多效唑和烯效唑溶液,单独浸种处理对3种草本植物发芽势及胚根和胚芽生长的影响.结果表明:矮壮素和烯效唑溶液降低了沙打旺和紫花苜蓿的胚芽长度比,提高了胚根长度比;300～400 mg/L的多效唑溶液对3种草本种子的发芽势均具有抑制效果,500 mg/L的烯效唑溶液对紫花苜蓿和高羊茅的发芽势都具有抑制效果.该研究可为植物生长延缓剂处理边坡绿化草本种子提供参考指标.     

保水剂在节水农业中的应用

本文研究了保水剂包膜涂层对大豆、小麦、绿豆等作物种子萌发成苗及保水剂蘸根对葡萄苗、山茱萸苗移栽成活率的影响，结果表明；1%保水剂包膜涂层可促进大豆、绿豆等豆类种子出苗率，使其出苗早，苗齐苗壮，抗旱能力增强，而对小麦玉米等淀粉种子的出苗无明显作用；低浓度的保水剂蘸根可提高苗木的成活率，促进其生长，增强抗旱能力，而高浓度的保水剂蘸根则降低苗木成活率，生长下降。     

外源GA3对盐胁迫下板蓝根种子萌发及幼苗 生理生化指标的影响

以板蓝根品种安徽亳州种为试材,在100 mmol/L Na Cl盐胁迫处理下,研究了外源GA_3对盐胁迫下板蓝根种子萌发及幼苗生理生化指标的影响。结果表明:当外源GA_3的浓度达到100 mg/L时,板蓝根种子萌芽能力和幼苗生长表现最优;同时,幼苗光合速率、蒸腾速率、气孔导度和胞间CO_2浓度的数值最大,分别为CO_2 5.53μmol/(m~2·s)、0.56 mmol/(m~2·s)、H_2O 216 mmol/(m~2·s)和287 mg/L;幼苗叶片中MDA含量达最低,而POD和SOD活性最高,其值分别为0.336μmol/g FW、26.65 U/(g·min)FW和272.53 U/(g·min)FW,可有效缓解盐胁迫对板蓝根种子萌发和幼苗生长造成伤害。     

Exogenous application of vitamins as regulators for growth and development of plants — a review

A survey of the recent literature on plant responses to exogenous vitamin application yielded the following results:

• Vitamins have been applied by soaking seeds, dipping cuttings, by sprays or dusts and as drenches to soils.
• Substantial yield increases due to exogenous vitamin application have been reported by a number of researchers.
• Vitamins may cause morphogenetic responses in plants. Most pronounced is the stimulation of root formation and of flowering under non-inductive conditions.
• Certain vitamins protect plants against ozone and sulfur dioxide, two important agents of air pollution.

     

介质阻挡放电低温等离子体处理对小麦种子活力及幼苗生理的影响

为揭示低温等离子体处理对小麦种子活力及幼苗生理特性的影响,该研究以济麦22、百农307为处理对象,对其进行不同时长（0、6、9、12、15 s）的介质阻挡放电（dielectric barrier discharge,DBD）低温等离子体处理,分析其对小麦种子萌发、幼苗生长、种皮形态结构、幼苗代谢生理及抗氧化性指标的影响。结果表明：以氩气为气源的DBD低温等离子体处理明显提高了小麦种子发芽率及其幼苗根苗长、鲜干重、活力指数;各处理时长条件下小麦种子吸水率均有所增加,当处理时间为9 s时,两种小麦种子的吸水率增幅最大,分别显著增加了6.4%（济麦22）、5.9%（百农307）（P<0.05）;小麦种子接触角随处理时间的延长而逐渐减小,表明其润湿性能逐渐提高;处理9 s时小麦的种皮结构组织轮廓模糊,呈现明显裂纹;处理后小麦种子的新生幼苗中光合色素含量、可溶性蛋白含量均得到不同程度的增加;处理后小麦种子的新生幼苗抗氧化能力有所提高,当处理时间为9 s时,两种小麦幼苗中的丙二醛含量降幅最大,分别显著降低了15.6%（济麦22）、18.0%（百农307）（P<0.05）。因此,DBD低温等离子体有效改善了小麦种子活力及其幼苗生理特性,可作为潜在的种子强化方法用于提高作物生产中的种子质量及促进后续小麦生长。     

Effects of water‐soluble constituents of plant residues on water uptake by seeds

Abstract

There has been strong support for the hypothesis that the adverse effects of plant residues on crop yields are due to phytotoxic compounds derived from these residues. This hypothesis is based largely on studies showing that, when compared with distilled water, aqueous extracts of plant residues have an adverse effect on seed germination and seedling growth. Because seed germination and seedling growth are reduced by a delay in germination resulting from slow uptake of water by seeds, we studied the possibility that the adverse effects of aqueous extracts of plant residues on seed germination and seedling growth might be at least partly due to water uptake by seeds being retarded by water‐soluble constituents of these residues. To test this possibility, we compared the rates of water uptake and germination of seeds of corn (Zea mays L.), soybean [Glycine max. (L.) Merrill], and wheat (Triticum aestivum L.) when these seeds were treated with distilled water and with aqueous extracts of corn, sorghum [Sorghum bicolor (L.) Moench], and wheat residues. We found that the rates of water uptake and germination of seeds treated with aqueous extracts of plant residues were appreciably slower than the corresponding rates for seeds treated with distilled water. This may be due to the water potentials of these extracts (ca. ‐50 kPa) because when seeds of corn, sorghum, and wheat were treated with a solution of polyethylene glycol 8000 having a water potential similar to that of the extracts of plant residues tested, the rates of water uptake and germination were also slower than the corresponding rates for seeds treated with distilled water. These observations suggest that the adverse effects of aqueous extracts of plant residues on seed germination and seedling growth when compared with distilled water may be partly due to constituents of these extracts inducing water potential effects that reduce water uptake by germinating seeds.     

马铃薯对瓜列当种子萌发的化感作用研究

瓜列当给瓜类等经济作物造成较大危害。本研究采用盆栽4个推广马铃薯品种"夏波蒂"、"青薯168"、"冀张薯5号"和"克新1号",以不同生长时期(幼苗期、开花期和结薯期)马铃薯根际土、根系和地上部的浸提液(甲醇和水)刺激瓜列当种子萌发,根据发芽率来判定其对瓜列当化感作用的强弱,同时筛选刺激瓜列当发芽率高的品种用于列当杂草的防除。结果表明,马铃薯能刺激瓜列当种子萌发;不同马铃薯品种对瓜列当的化感作用各有差异,随着马铃薯的生长,根际土中化感物质积累不断升高,根系化感作用逐渐减弱,而地上部化感作用逐渐增强。甲醇浸提液刺激瓜列当种子发芽率高于水浸提液,即甲醇浸提化感作用效果较好。"夏波蒂"根系甲醇浸提液刺激瓜列当种子的发芽率在幼苗期最高,为48.5%;而地上部甲醇浸提液处理的发芽率在结薯期最高,为51.2%。可以在瓜列当危害的农田轮作"夏波蒂"5~8年,同时采用马铃薯秸秆还田来减少土壤中瓜列当种子库,达到防除瓜列当危害的目的。     

Zinc‐biofortified seeds improved seedling growth under zinc deficiency and drought stress in durum wheat

High zinc (Zn) concentration of seeds has beneficial effects both on seed vigor and human nutrition. This study investigated the effect of Zn biofortification on growth of young durum wheat (Triticum durum cv. Yelken) seedlings under varied Zn and water supply. The seeds differing in Zn concentrations were obtained by spraying ZnSO₄ to durum wheat plants at different rates under field conditions. Three groups of seeds were obtained with the following Zn concentrations: 9, 20, and 50 mg Zn kg^?1. The seeds differing in Zn were tested for germination rate, seedling height, shoot dry matter production, and shoot Zn concentration under limited and well irrigated conditions in a Zn‐deficient soil with and without Zn application. In an additional experiment carried out in solution culture, root and shoot growth and superoxide dismutase activity (SOD) of seedlings were studied under low and adequate Zn supply. Low seed Zn concentration resulted in significant decreases in seedling height both in Zn‐deficient and sufficient soil, but more clearly under water‐limited soil condition. Decrease in seed germination due to low seed Zn was also more evident under limited water supply. Increasing seed Zn concentration significantly restored impairments in seedling development. Drought‐induced decrease in seedling growth at a given seed Zn concentration was much higher when soil was Zn‐deficient. Increasing seed Zn concentration also significantly improved SOD activity in seedlings grown under low Zn supply, but not under adequate Zn supply. The results suggest that using Zn‐biofortified seeds assures better seed vigor and seedling growth, particularly when Zn and water are limited in the growth medium. The role of a higher antioxidative potential (i.e., higher SOD activity) is discussed as a possible major factor in better germination and development of seedlings resulting from Zn‐biofortified seeds.     

Evaluation of the simultaneous effects of processing parameters on the iron and zinc solubility of infant sorghum porridge by response surface methodology

The purpose of this study was to improve the micronutrient quality of indigenous African infant flour using traditional techniques available in the region. Response surface methodology was used to study the effect of duration of soaking, germination, and fermentation on phytate and phenolic compounds (PC), pH, viscosity, and the in vitro solubility (IVS) of iron and zinc in infant sorghum flour. The phytate and the PC concentrations of the flour were significantly modified as a result of the duration of germination and fermentation and their mutual interaction. These modifications were accompanied by a significant increase in % IVS Zn after 24 h of sprouting. Except for the interaction of soaking and fermentation, none of the processing parameters exerted a significant effect on the % IVS Fe. The viscosity of the porridge prepared with the flour decreased significantly with the duration of germination, making it possible to produce a porridge with high energy and nutrient density. The use of germination in combination with fermentation is recommended in the processing of cereals for infant feeding in developing countries.     

壳聚糖对不同种源柠条种子发芽及其酶活性的影响

用不同浓度壳聚糖乙酸溶液分别对陕西省的吴起县和榆林市榆阳区两个产地的柠条种子浸种处理,以清水浸种处理为对照,调查种子发芽及幼苗生长特性,并测定了萌发过程中种子α-淀粉酶、脱氢酶、过氧化物酶、过氧化氢酶活性。结果表明,壳聚糖能促进柠条种子的萌发,缩短发芽时间;随着处理浓度的增大,各项发芽指标及各种酶活性先升高后降低,且不同种源柠条种子对壳聚糖浓度的反应不同。当壳聚糖浓度为0.5%时,榆阳柠条种子的发芽率是对照的1.2倍,平均发芽速率缩短0.9d,各种酶活性比对照显著提高,处理效果最佳。当壳聚糖浓度为1.0%时,吴起柠条种子发芽率比照提高13%,平均发芽速率缩短1.7d,各种酶活性比对照显著提高,处理效果最佳。当壳聚糖浓度达到1.5%时,对榆阳柠条种子的萌发有一定的抑制作用,而对吴起柠条种子萌发无抑制作用。壳聚糖对柠条幼苗的生长也有一定的影响,表现在幼苗的根长、苗高、干重、鲜重和叶绿素含量均显著高于对照,吴起柠条和榆阳柠条最佳的处理浓度分别为1.0%和0.5%。     

胆碱脂肪酸/氨基酸对PEG模拟干旱胁迫下玉米萌发的影响

为探究秸秆预处理过程中产生的胆碱类离子液体残液对干旱胁迫下玉米种子萌发的影响,以典型农作物玉米(Zea mays L.)为研究对象,使用13％聚乙二醇-6000(PEG)模拟干旱胁迫,以种子萌发参数、根芽长、种胚抗氧化酶活性为指标,研究200 mg·L-1胆碱脂肪酸离子液体(胆碱己二酸、胆碱辛二酸)和胆碱氨基酸离子液体...     

Seed nitrogen accelerates the rates of germination,emergence, and establishment of rice plants

We examined the effect of seed nitrogen content on the rates of germination, emergence, and establishment of rice plants. Several seed lots with various nitrogen contents were obtained from the parent plants grown under 3 planting densities and 4 rates of nitrogen application. There was a clear negative correlation between the seed nitrogen content and germination time (R =0.88), whereas the correlation between the seed dry weight and germination time was very low (R=0.23). The seed lot with a high nitrogen content absorbed water faster than the seed lot with a low nitrogen content, especially on the first day after soaking, and also showed a faster emergence, exsertion of the fourth leave, and a more uniform germination. Moreover, the increase of seed nitrogen content as well as the prolongation of soaking time resulted in a uniform emergence. Therefore, seed vigor is likely to be enhanced by the increase of seed nitrogen content, which may be achieved by an adequate application of a large amount of nitrogen to parent plants. Consequently, it may be possible to improve and stabilize the establishment of directly sown rice plants by the sowing of vigorous seeds with a high nitrogen content.