GA3和KNO2引发处理对水稻芽期生长、淀粉及呼吸代谢的影响

种子引发作为一种播前处理技术,其对种子萌发和幼苗生长的促进作用已被广泛报道,赤霉素(GA₃)和亚硝酸钾(KNO₂)均参与调控种子发芽过程。但是,GA₃引发和KNO₂引发对水稻种子萌发出苗及相关生理代谢过程的影响及其复合效应尚不清楚。本研究以常规稻湘早籼45号和杂交稻株两优4024为供试品种,在生长箱条件下,以非引发处理为对照(CK),探究水引发(HP)、赤霉素引发(GA₃)、亚硝酸钾引发(KNO₂)和复合引发(GA₃+KNO₂)处理对水稻种子萌发、幼苗生长、淀粉降解代谢和呼吸代谢的影响。结果表明,与CK相比,不同引发处理均显著提升了种子发芽指数和活力指数,增强了幼苗素质,且GA₃引发和KNO₂引发的促进作用要优于HP引发;同时,GA₃引发和KNO₂引发较CK和HP引发显著提升了种子萌发过程中的α-淀粉酶活性和可溶性糖含量,一定...     

引发剂结合固体基质引发对三倍体西瓜种子发芽性能的影响

种子发芽出苗率低是制约三倍体无籽西瓜生产的主要原因。试验以红小玉为材料,用0.1%H2O2,0.1%CuSO4+2%KNO3+KH2PO4混合液和20 m g/kg的GA3丙酮溶液作引发剂,在固体基质中吸湿32 h后回干,通过砂床发芽试验,测定种子萌发率和幼苗素质。结果表明,种子萌发率提高了44.6~62.4个百分点,并显著提高了发芽势、幼苗鲜重和根系活力。其中,GA引发处理的种子发芽率达88.23%,与破壳处理(CK 1)接近,比未处理(CK 2)提高了62.47个百分点;3种处理的苗鲜重均显著高于CK 1和CK 2,处理间差异不显著;3种处理均显著提高了幼苗根系活力,以0.1%H2O2处理效果最佳。3种引发剂结合固体基质引发处理,均可有效提高三倍体西瓜种子萌发率,并为培育壮苗奠定了基础。在固体基质处理过程中,西瓜种子吸水缓慢,给细胞膜的修复提供了时间,是种子可以达到引发促萌的原因之一。     

砂引发对荞麦种子萌发及活力的影响

试验选用安徽甜荞-1、安徽甜荞-2、青海甜荞、青海苦荞4个荞麦种子样品为材料,每品种设置4种处理,研究不同含水量的砂基质引发对荞麦种子萌发及活力的影响。结果表明,适宜的砂引发处理能不同程度地提高荞麦种子的活力,砂引发基质的适宜含水量安徽甜荞-1、安徽甜荞-2和青海甜荞均为5．7％,青海苦荞为3．8％。     

引发提高水稻劣变种子发芽率的蛋白质组学分析

引发处理是目前简便有效的提升种子发芽率和整齐度的方法,但引发提高水稻劣变种子发芽能力的机理并不清楚。利用蛋白质组学方法,分析清水引发和藤茶提取物二氢杨梅素引发2种处理方法与对照的差异蛋白,初步揭示引发提升种子发芽能力的机制。分析双向电泳图谱差异获得2倍以上显著差异蛋白点79个,通过MALDI TOF/TOF MS质谱分析鉴定出74个蛋白,其中2种引发处理与未引发对照相比同步上调或下调的共有蛋白,即引发相关蛋白有57个。分析引发相关蛋白可知,绝大多数的逆境防御蛋白类、能量相关蛋白类以及蛋白质合成和目标类蛋白丰度在引发处理中显著增加,推测引发提高种子发芽率的原因与逆境记忆、能量代谢活动和蛋白质合成能力增强等密切相关。     

特用玉米种子沙引发处理对其萌发及幼苗生理特性的影响

以糯玉米、爆裂玉米和甜玉米3种特用玉米为材料,测定沙引发处理后种子萌发指标、幼苗形态和生理指标的变化。结果表明,沙引发能显著提高糯玉米和甜玉米的种子活力,对3种特用玉米的幼苗生长具有显著的促进作用,但对种子发芽率无显著影响。沙引发处理显著提高了3种类型特用玉米幼苗的过氧化物酶(POD)和超氧化物歧化酶(SOD)活性,显著降低了丙二醛(MDA)含量。沙引发效果受基因型影响,对种子萌发的促进作用表现为糯玉米>甜玉米>爆裂玉米;对幼苗生长的促进作用表现为甜玉米>爆裂玉米>糯玉米。沙引发能够提高幼苗体内抗氧化酶的活性,从而增强幼苗对外界环境的适应能力。     

我国甜菜种子引发研究进展

种子引发可提高植物种子活力、发芽率和抗病性。本文综述了我国甜菜种子引发技术的研究现状,分析了甜菜种子引发研究面临的问题,并对未来进行展望。     

砂引发对谷子种子活力的影响

试验选用长生04、长农35、长农36、长农38、长农39和晋谷27共6个谷子品种为材料,每品种设置3种处理,研究不同含水量的砂基质引发对谷子活力的影响,结果表明,适宜的砂引发处理能提高谷子种子的活力,6个谷子品种砂引发基质的适宜含水量均为1％。     

几种化学药剂对杂交籼稻汕优63自然老化种子引发效果研究

用聚乙二醇（PEG）、聚乙烯醇（PVA）、KNO3、PEG＋KNO3、PVA＋KNO3等几种化学药剂对自然老化的杂交籼稻汕优63种子进行引发效果研究,以筛选最佳处理方法。结果表明,从引发效果和经济实用两方面考虑,以0.5%PVA＋1.0%KNO3处理1 d为最佳。经过该处理的汕优63自然老化种子的发芽率显著提高,比对照（63.0%）提高了11.7个百分点,活力指数、发芽势、苗高、苗重也均较对照显著提高,且成本较低。     

拮抗菌在新疆棉花黄萎病防治中的初步应用

通过对3个不同黄萎病抗性的棉花品种进行种子引发、丸粒化、引发+丸粒化+灌根3种方式处理,同时在棉花黄萎病鉴定圃调查拮抗菌3种处理方法的田间防效,确定拮抗菌最佳应用方式为“引发+丸粒化+灌根”,接菌浓度为1×109 cfu·mL-1；拮抗菌处理对3个不同黄萎病抗性的棉花品种第一次发病高峰的黄萎病田间防效可达30％～70％.初步建立了一种棉种携带拮抗菌制剂在棉花黄萎病防治中应用的方法.     

多巴胺引发对盐胁迫下水稻种子萌发及幼苗生长的影响

[目的]探讨多巴胺(Dopamine,DA)引发对盐胁迫下水稻种子萌发及幼苗生长的影响.[方法]以新疆自育水稻品种新稻17号为研究对象,分别用0(纯水)、0.1、0.5、1、1.5 mg/L的DA溶液(分别用S0、S0.1、S0.5、S1、S1.5表示)引发种子,采用浓度为100 mmol/L的NaCl溶液模拟盐胁迫,...     

Influence of Seed Priming on Performance and Water Productivity of Direct Seeded Rice in Alternating Wetting and Drying

Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated the effect of seed priming and irrigation on crop establishment, tillering, agronomic traits, paddy yield, grain quality and water productivity of direct seeded rice in alternate wetting and drying(DSR-AWD) in comparison with direct seeded rice at field capacity(DSRFC). Seed priming treatments were osmo-priming with KCl(2.2%), Ca Cl2(2.2%) and moringa leaf extracts(MLE, 3.3%) including hydro-priming as control. Among the treatments, seed osmo-primed with MLE emerged earlier and had higher final emergence, followed by osmo-priming with Ca Cl2. Tillering emergence rate and number of tillers per plant were the highest for seed priming with Ca Cl2 in DSRAWD. Total productive and non-productive tillers, panicle length, biological and grain yields, harvest index were highest for seed priming with MLE or Ca Cl2 in DSR-AWD. Similarly, grain quality, estimated in terms of normal grains, abortive and chalky grains, was also the highest in DSR-AWD with MLE osmo-priming. Benefit cost ratio and water productivity was also the highest in DSR-AWD for seed priming with MLE. In conclusion, seed priming with MLE or Ca Cl2 can be successfully employed to improve the direct seeded rice performance when practiced with alternate wetting and drying irrigation.     

Seed Priming with Beta-Amino Butyric Acid Improves Abiotic Stress Tolerance in Rice Seedlings

We studied the influence of seed priming with beta-amino butyric acid(BABA) on the growth, physiological and biochemical parameters of seedlings with varied abiotic stress tolerance, which were raised and grown under unstressed and stressed(NaCl/PEG-6000) conditions. Under stressed conditions, the growth of rice seedlings was less when compared to control plants. After BABA priming, the seedling growth increased both under unstressed and stressed conditions as compared to the respective controls. BABA priming of rice seeds caused increase in the photosynthetic pigment content of the leaves, modified the chlorophyll a fluorescence related parameters and also enhanced the photosystem activities of seedlings when compared to their respective non-primed controls. BABA priming also caused increased mitochondrial activities of the rice seedlings. Moreover, BABA priming significantly reduced malondialdehyde content in the seedlings and also resulted in accumulation of proline especially in the NaCl tolerant variety Vyttila 6. BABA seed priming also enhanced the activity of nitrate reductase enzyme and activities of antioxidant enzymes like guaiacol peroxidase and superoxide dismutase. The presence of BABA was detected by high performance thin layer chromatography analysis in the rice seeds whereas in the seedlings it was not detected. Thus, it can be inferred that the seed priming effect of BABA mainly occurred within the seeds, which was further carried to the seedlings. It is concluded that BABA priming of seeds improved the drought and salinity stress tolerance of all the three rice varieties and it was significantly evident in the drought tolerant variety Vaisakh and NaCl tolerant variety Vyttila 6, when compared to the stress sensitive variety Neeraja.     

Soak conditions and temperature following sowing influence the response of maize (Zea mays L.) seeds to on-farm priming (pre-sowing seed soak)

On-farm seed priming of maize (i.e. soaking seed in water overnight, 17 h) in the semi-arid tropics has been shown to improve crop establishment and yield but the benefits can be variable. In previous work, this variation was thought to result from the interaction between primed seeds and conditions in the seedbed following sowing. To investigate this interaction, experiments were carried out under controlled temperature conditions that represented those of seedbeds in the semi-arid tropics. The conditions during seed priming and during subsequent germination and emergence were investigated as potential causes of variable seedling emergence relative to that of untreated seeds. Priming advanced emergence from moist sand cores at 30 °C/20 °C (day/night), reduced emergence at 35 °C/28 °C and delayed and reduced emergence at 40 °C/28 °C. In drier cores (drained 8 days) at 35 °C/28 °C, priming advanced germination time and did not decrease final percentage emergence. These results confirmed earlier field observations that the effect of priming in maize can vary and lead to positive, neutral or negative effects. Priming decreased the optimum and ceiling temperatures for germination, and unlike untreated seeds, the relationship between germination rate and sub-optimal temperature was not linear in all cases. Pre-humidifying seeds did not enhance the effect of priming, but aerating the soak water did. These results indicate that variable results from priming recorded in the field were not due to imbibitional damage, but may result from the negative effects of hypoxia during soaking exacerbated by moist conditions and high temperatures at sowing. These effects differed between seedlots of different cultivars, indicating the importance of selecting more tolerant maize hybrids to reduce variation in response to priming following sowing in the field. The implications of these findings for the use of primed seeds in the field are discussed.     

土壤氮激发效应及其微生物机理研究进展

土壤氮激发效应是土壤养分释放、植物养分吸收过程中的关键机制。对土壤氮素激发的深入了解,不仅有助于农业生产上更加合理制定氮肥运筹,从而提高氮肥的利用率,也有利于评估和控制环境污染并提供有效的治污方法。本文在介绍土壤氮素激发效应概念和机制的基础上,评估目前土壤氮素激发效应的主流测定方法及其在实际应用中的优劣,重点阐述了外源添加物(无机氮肥、有机物料和根系分泌物)对土壤氮素激发效应的作用效果及其微生物机理。土壤氮激发模式中,外源添加物对土壤C/N比的影响可能是土壤氮激发效应作用的关键。当系统中有效C冗余时,施用无机氮肥,促进土壤有机氮的分解,从而表现正的激发效应;反之,有效C不足但有效N富集时,则表现为固氮微生物活性相对增强,从而出现负的激发效应。微生物是激发效应的推动者。本文通过共代谢理论、微生物热区理论和微生物能量与物质转化理论三个理论假说解析了微生物在土壤氮激发过程中可能的作用机制,从而深化对激发效应的认识,为进一步明确土壤激发效应的微生物机制、因素之间的互作效应及通过激发效应为提高氮肥利用效率提供有效途径。