Seedling development

Water uptake, increasing respiration and the biochemical events described in detail in Chapter 5 culminate in the growth of the embryo and the development of the seedling, provided of course that the seed is not dormant. The first 

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In a replacement-series study, Elmore et al. (27) have shown that purple nutsedge is a stronger competitor than four other species, including cotton. The data are insufficient to document allelopathy, but nutsedge tuber residue has been shown to affect cotton seedling development (31). 

Radicle elongation was quite linear with time (r = 0.98, minimum). Pretreating the seed with DCM reduced early radicle growth, but by 96 h the sterol/DCM treated seed achieved radicle lengths equal to that of the H2O control and 30% more than those of DCM controls. The experiment was terminated at 96 h when space limitations in the petri dishes and near-anaerobic conditions during incubation began to interfere with seedling development. There were no secondary roots visible after 96 h. 

Gaikwad, S.K. and V.M. Pawar. 1979. Effect of systemic insecticides on the germination and seedling development of okra (Abelmoschus esculentus (L) Moench). Seed Res. 7 28-33. 

Yakle GA, Cruse RM (1984) Effects of fresh and decomposing com plant residue extracts on com seedling development. Soil Sci Soc Am J 48 1143-1146 Young CC, Zhu Thoume LR, Waller GR (1989) Phytotoxic potential of soils and wheat straw in rice rotation cropping systems of subtropical Taiwan. Plant Soil 120 95-101 Yu JQ (2001) Autotoxic potential of cucurbit crops phenomenon, chemicals, mechanisms and means to overcome. J Crop Prod 4 335-348... 

X. W. The roles of photoreceptor systems and the COPl-targeted destabilization of HY5 in light control of Arabidopsis seedling development. Plant Physiol. 2000, 124, 1520-1524. 

Ma, L, Zhao, H., Deng, X. W. Analysis of the mutational effects of the COP/DET/FUS loci on genome expression profiles reveals their overlapping yet not identical roles in regulating Arabidopsis seedling development. Development 2003, 330, 969-981. 

B) Chemical substances can be extracted from knapweed that inhibit seed germination or seedling development of other species in vitro. However, application of air-dried knapweed to field plots had no effect on grass yield. It appears that under field conditions, knapweed leachates are not phytotoxic. 

D) In many examples of allelopathy, plant phenols are implicated as a component of the phytotoxin and therefore it would be reasonable to expect phenols to be Involved in this situation. However, our studies failed to show an accumulation of soluble phenols in the soil. A substantial elevation in soil phenol levels would be required to inhibit seedling development, and phenolics were not detected in root exudates. 

Flavonoids often participate in plant reproduction, in the protection of reproductive tissues and seeds, and in seedling development. This may, in part, be due to their role in UV light shielding (thereby protecting DNA) and antioxidant properties, but other functions are also important. 

Ndakidemi, P.A. and Dakora, F.D., Legume seed flavonoids and nitrogenous metabolites as signals and protectants in early seedling development, Funct. Plant Biol, 30, 729, 2003. 

B. Seed morphology, seedling development, growing stages, diseases, and pests... 

Table III. Effect of Photoperlod and Gibberellin A3 Treatments during Seedling Development on Flowering of Cu umis sativus L., var. Wisconsin SMR-12...

Selmar, D., Grocholewski, S. and Seigler, D.S. (1990) Cyanogenic lipids utilization during seedling development of Ungnadia speciosa. Plant Physiol., 93,631-6. 

Swain, E. and Poulton, J.E. (1995) Utilization of amygdalin during seedling development of Prunus serotina. Plant Physiol., 106, 437-45. 

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