Name: Course: Instructor: Date: The Lazarus effect: Rejuvenation of Leaf-senescent Seedlings in a rare Grassland Perennial Introduction According to the article “The Lazarus effect” the authors identify various forms of dominancy in plants, which include seed dominancy, bud dominancy, and stress induced dominancy. There is no growth of the seed for a certain period in seed dominancy.
Bud dominancy is the time before a leaf or flower bud grows into a leaf or flower (Vickery, Sulzer, and Kelly 212). On the other hand, stress-induced dominancy is the outcome of harsh environmental conditions like drought. Nevertheless, with improved environmental conditions there may be an appearance of the second leaf in the same growing period particularly in temperate regions.
Hypotheses 1. The northern blazing star seeds do not provide enough nutrients for their seedlings due to their small size. 2. The mortality rate of the northern star blazing is high during summer time. Materials and methods of Observations This research provides information concerning the seedlings of an herbaceous grassland perennial developing into dominancy because of premature leaf-senescence caused by severe environmental conditions like drought. However, these seedlings may break the dominance by developing new leaves in the same period. This type of reaction has been referred to as “the Lazarus effect” as revealed in the New Testament where Lazarus died and was risen from the dead after four days (Vickery et al.
212). For the method used, it is noted that the research was carried out from Kennebunk York County with the main intention of researching on the impacts of fire on the reproductive ecology of northern blazing stars at that location. This plant is always found in the rare grassland perennial in the group of Asteraceae, usually in the habitat such as sandplain grasslands, heathland and pitch pine.
The article also cites other research on the same plant that was carried out in Southern Maine with the results that the seed of northern blazing star mainly germinates in May. Results The results of this particular research revealed that the mortality rate of the northern blazing star seedlings is extremely high especially during summer time. This was seen after finding out about 60% of the marked seedlings died.
Some seedlings were found dead, but further investigation showed the seedlings had developed a new shoot with green leaves. The new shoot meant there was a new development on the dominant seedlings. However, due to the prolonged periods of drought by the late June in 1994 and 1995, the seedlings were noted to be completely dominant. About 42 percent of the seedlings termed as being dominant for averagely two to four weeks managed to survive into another year (Vickery et al., 213). For instance, about 60 percent of the group in 1994 managed to reach their second year, while about 28 percent in 1995 reached their second year.
Generally, about 53% of the dominant seedlings managed to survive up to their second summer (Morgan 2011). Based on these results, it was inferred that the growth of the new shoot in desiccated seedlings was a surprise because the northern blazing star seeds are known to be small hence, did not give enough nutrient support to the seedlings. Nevertheless, by September the northern blazing star had developed a small corn implying that the seedlings were in position to keep enough reserves within the corn in order to sustain the plant during the long periods of drought.
Conclusion The late rain periods are important as a way of enhancing the growth of new leaves and there were no rejuvenation seedlings in 1996, which was the time when there was no rain during the month of August. The most significant factor in the northern blazing star seedling dormancy was that this reaction did not lead to reduced survivorship of the seedlings. Therefore, the ability of the seedling to become dominant through premature leaf-senescence is known to be very adaptive for the northern blazing star, a plant germinating in xeric poor nutrient habitats. Works Cited Morgan, H. The Ecological restoration: woodlands. Board of Regents of the University of Wisconsin System.
New York, Routledge, 2011. Retrieved from: http://er.uwpress.org/ Vickery, Peter D.
, Andrea M. Sulzer, and Sharon Kelly. The Lazarus Effect: Rejuvenation of Leaf-Senescent Seedlings in a Rare Grassland. American Midland Naturalist. 141.1 (1999): 212-214