Temperature sensitivity of the low-moisture-content limit to negative seed longevity-moisture content relationships in hermetic storage
Temperature sensitivity of the low-moisture-content limit to negative seed longevity-moisture content relationships in hermetic storage
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DOI：
10.1093/aob/mcl035
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发表时间：
2006-05-01
期刊：
影响因子：
4.2
通讯作者：
Hong, TD
中科院分区：
文献类型：
--
作者：
Ellis, RH;Hong, TD
背景与目的在密闭贮藏中，正统种子寿命与水分含量之间的负对数关系受到低水分限制(m(C))的影响，但m(C)是否受温度的影响？方法将红三叶(Trifolium Pratense)和紫花苜蓿(Medicago Sativa)种子在12个水分含量(2-15%)和5个温度(-20、30、40、50和65℃)下密闭储存14.5年，关键结果红三叶和紫花苜蓿在水分含量分别为2.2%~14.9%和2.0%~12.0%的条件下，在-20℃下密闭贮藏14.5年，活力无明显变化。在30-65℃温度范围内，寿命与水分含量呈负对数关系，在低水分时不连续；m(C)在4.0-5.4%(红三叶)或4.2-5.5%(紫花苜蓿)之间变化，取决于贮藏温度。在调查的范围内，在任何一个温度下将水分含量降低到m(C)以下都不会对寿命产生影响。温度越低，m(C)的估计值越大，关系(P<；0.01)为曲线。在m(C)以上，C-H和C-Q(即种子活力方程中的温度项)在不同物种之间没有差异(P>；0.10)，而K-E和C-W的估计值有差异(P<；0.001)。结论在密闭贮藏中，种子寿命与水分之间的负对数关系的低水分极限增加了约10℃。这些物种在35摄氏度以上占1.5%(65摄氏度时为4.0-4.2%，30-40摄氏度时为5.4-5.5%)。水分含量的进一步降低不会造成损害。M(C)的变化意味着寿命对高于m(C)的温度比低于m(C)的温度更敏感。这一点得到了证实(P<；0.005)。
Background and Aims The negative logarithmic relationship between orthodox seed longevity and moisture content in hermetic storage is subject to a low-moisture-content limit (m(c)), but is m(c) affected by temperature?Methods Red clover (Trifolium pratense) and alfalfa (Medicago sativa) seeds were stored hermetically at 12 moisture contents (2-15 %) and five temperatures (-20, 30, 40, 50 and 65 degrees C) for up to 14.5 years, and loss in viability was estimated.Key Results Viability did not change during 14.5 years hermetic storage at -20 degrees C with moisture contents from 2.2 to 14.9 % for red clover, or 2.0 to 12.0 % for alfalfa. Negative logarithmic relationships between longevity and moisture contents > m(c) were detected at 30-65 degrees C, with discontinuities at low moisture contents; m(c) varied between 4.0 and 5.4 % (red clover) or 4.2 and 5.5 % (alfalfa), depending upon storage temperature. Within the ranges investigated, a reduction in moisture content below m(c) at any one temperature had no effect on longevity. Estimates of m(c) were greater the cooler the temperature, the relationship (P < 0.01) being curvilinear. Above m(c), the estimates of C-H and C-Q (i.e. the temperature term of the seed viability equation) did not differ (P > 0.10) between species, whereas those of K-E and C-W did (P < 0.001).Conclusions The low-moisture-content limit to negative logarithmic relationships between seed longevity and moisture content in hermetic storage increased the cooler the storage temperature, by approx. 1.5 % over 35 degrees C (4.0-4.2 % at 65 degrees C to 5.4-5.5 % at 30-40 degrees C) in these species. Further reduction in moisture content was not damaging. The variation in m(c) implies greater sensitivity of longevity to temperature above, compared with below, m(c). This was confirmed (P < 0.005).