Factors affecting dormancy, germination, and seedling development of aeginetia indica l. (orobanchaceae)

TLDR: A germination medium was developed that suppressed microbial contamination and permitted long-term observation of these slow-germinating seeds and it was found that brief, intermittent light exposures depressed germination.

Abstract: A B S T RA CT Dormancy in seeds of the parasitic phanerogam Aeginetia indica L. can be broken by chemical treatment with sodium hypochlorite, which also helps to control contaminating microflora. A germination medium was developed that suppressed microbial contamination and permitted long-term observation of these slow-germinating seeds. The medium consisted of 10 ppm streptomycin, 10 ppm penicillin, and 10-' M indole-3-acetic acid (IAA) (or other growth regulator) in 1 % water agar. Optimum germination range was 25-30 C. Dormancy could also be broken by exposure on agar for several days at 3-5 C (stratification), or by brief exposures (15 min) to 50 C. Continuous light as low as 0.1 ft-c completely inhibited germination on this growth medium. Brief, intermittent light exposures depressed germination. Germination and growth in vitro of nondormant seed of Aeginetina indica L. can be described in five stages: (1) Germination: expansion of spheroidal cells or nodule at micropylar end of the seed, stimulated