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We studied the influence of temperature and near- and sub- optimal mineral nutrition of black spruce seedlings (Picea mariana [Mill.] B.S.P.) during their second growing period on bud set, bud development, growth, mineral content and cold tolerance. Bud break and growth after bud break were also studied. Seedlings were grown for 106 d in growth chambers under three temperature regimes in combination with three concentrations of a fertilizer. They were then cold hardened for 56 d and dehardened for 66 d.Under these near- and sub-optimal N levels, bud formation occurred during the growing season. Bud formation was accelerated with decreasing fertilization, but was not affected by temperature treatments. Needles from seedlings with 0.64% N (dry mass basis) before hardening did not harden. Those with 0.87% N showed a lesser degree of hardiness than those with 1.28% N. Stem diameter increased at the beginning of the hardening period. During this acclimation period, shoot dry mass decreased with time at a constant rate and at the same rate over time for all treatments whereas root dry mass was more variable. Total number of needle primordia was low and no difference was observed among growing conditions. Bud break was similar in all treatments. Following bud break, shoot height and stem diameter increases were small but their magnitude varied with the nutritional regimes applied during the previous growing period. During hardening, nitrogen concentration of shoot tissues first increased and then decreased; phosphorus concentration first increased and then remained stable; potassium concentration remained stable. Concentration of these three elements generally decreased in the roots during this hardening. 相似文献
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Anders Lindström Eva Stattin Daniel Gräns Elisabeth Wallin 《Scandinavian Journal of Forest Research》2014,29(8):717-724
As indoor frozen storage is increasing in forest tree nurseries it is important to have accurate methods for assessing seedling storability in autumn and methods to determine post-storage vitality. Storability of spruce (Picea abies (L.) Karst.) and pine (Pinus sylvestris L.) seedlings can be based on determination of dry matter content (DMC) of seedling shoots or by freezing shoots at –25°C and thereafter measure electrolyte leakage (SELdiff–25). To compare these two methods we stored 1-year-old spruce and pine seedlings at different occasions during the autumn. To test if leakage of electrolytes from shoots (SEL) could indicate deteriorated vitality, we measured SEL at the end of storage. After storage seedling viability was determined in a three-week growth test, measuring shoot and root growth capacity (RGC). Determination of freezing tolerance (SELdiff–25) before storage had a better ability to predict the outcome of storage compared to the DMC test. Measuring SEL at the end of the frozen storage period accurately indicated seedling vitality. Seedlings with SEL of 0–5% had a high survival rate whereas SEL over 10% indicated low survival and growth capacity after storage. The SEL method has a potential to become a screening test for identifying batches of seedlings that have been damaged during storage in the nursery. 相似文献
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不同小麦基因型抗寒性与冷适应特征的评价 总被引：2，自引：0，他引：2
用存活率和离子渗透检测法测定了18个来自波兰和中国的小麦品种的抗寒性。试验结果表明，离子渗透检测分辨率最高的温度是－10℃，两种检测方法结果相关极显著（n＝18，r＝0．940^**），冷冻叶片和冷冻植株的离子渗透检测结果相一致（n＝18，r=0．706^**）。Jubilatka,Roma,Mikon,和Maltanka诱导后抗寒性强于其它供试品种，其抗寒性与Mironovska808相当；Maltanka的诱导抗寒性最强；豫麦10号的抗寒性中等；波兰的主栽品种Almari抗寒性较弱。供试品种的去抗寒锻炼速度存在很大差异，但抗寒性与去抗寒锻炼速度间无相关性。检测了抗寒性强和弱的品种对不同去抗寒锻炼处理长度的反应，结果表明：8d的去抗寒处理不能完全消除诱导抗寒性。分析认为，抗寒性强的品种Maltanka,Mikon和Mironovska808有着不同的抗寒机制。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):271-284
The time constant of the dehardening of one‐year‐old Scots pine (Pinus sylvestris L.) seedlings was studied in three experiments started at different times of the year. The seedlings were transferred from outside to the different controlled conditions in January (Exp. 1), March (Exp. 2) and April (Exp. 3). Changes in the frost resistance of the seedlings were followed on the basis of the temperature response of the specific impedance difference in the shoot. The time constant for dehardening at a temperature of 7.5°C was found to be about 12 days in Exp. 1, about 8 days in Exp. 2, and about 5 days in Exp. 3. the terminal bud burst when the frost resistance of the shoot had risen to about ‐10°C. 相似文献
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通过对电阻抗图谱(EIS)参数及抗性生理指标的测定,研究了6种不同观赏树木金枝国槐(Sophora japonica‘Golden Stem’)、蝴蝶槐(Sophora japonica var.loligpophylla)、西府海棠(Malus micromalus Mak.)、红宝石海棠(Malus spetabilis Royalty)、腊梅(Chimonanthus praecox(L.)Link)和大叶女贞(Ligustrun lucidumAit)的脱锻炼期间抗寒性的变化及与EIS参数和生理指标之间的相关性,为揭示不同观赏树种在脱锻炼期间抗寒机理提供理论依据。结果表明:脱锻炼期间,6种树种的茎EIS参数呈现出不同程度的变化趋势;可溶性淀粉和糖含量发生了明显的变化;抗寒性均呈下降趋势。6种树种的抗寒性与某些生理指标、EIS参数存在着一定的相关性。 相似文献
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脱锻炼期间白皮松针叶的电阻抗图谱参数和生理指标的相关性 总被引：5，自引：1，他引：4
2007年3—5月, 对北京十三陵苗圃的北京蟒山、山西孝义和甘肃两当3个种源的9年生白皮松( Pinus bungeana Zucc. ) 针叶进行了电阻抗图谱( EIS) 分析, 测定其未冷冻针叶的EIS参数, 以及超氧化物歧化酶( SOD) 活性、过氧化物酶( POD) 活性、丙二醛(MDA) 含量、可溶性蛋白质、脯氨酸和干物质含量等生理指标的变化, 比较脱锻炼期间不同种源白皮松针叶的EIS参数和生理指标之间的相关性。结果表明: (1) 脱锻炼期间未冷冻针叶的EIS参数β和胞外电阻率re与针叶的脯氨酸含量之间存在负相关;细胞膜时间恒量τm与针叶的可溶性蛋白质含量存在正相关; (2) 胞内电阻率ri与MDA, τm与干物质含量的变化趋势相同, 而re和β在脱锻炼前期与可溶性蛋白质含量的变化趋势类似; (3) 冷冻处理后用τm和re求出的抗寒性与脯氨酸含量相关。 相似文献
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