Sk. Douglass et al., SWEET CORN SEEDLING EMERGENCE AND VARIATION IN KERNEL CARBOHYDRATE RESERVES, Seed science and technology, 21(2), 1993, pp. 433-445
Seed of 24 sweet corn genotypes homozygous for either the sugary1 (su1
),sugary enhancer (se1), or shrunken2 (sh2) endosperm mutations were p
lanted in replicated field plots to evaluate for comparative seedling
emergence, vigour and uniformity in cold spring soils. Percentage emer
gence, averaged over the genotypes with either the su1, se1, or sh2 mu
tations was 69, 46, and 44%, respectively. Variability among se1 genot
ypes indicated that cold emergence could possibly be improved to equal
that observed in some of the best su1 varieties. Quantitative amounts
of individual sugars (fructose, glucose, sucrose, and maltose), phyto
glycogen, and water insoluble starch from remnant mature dry seed of e
ach genotype were determined by laboratory analysis. Mean kernel total
sugar content in mg/g dry weight for su1, se1, and sh2 genotypes was
28.6,42.1 and 47.0, respectively. A highly significant correlation was
found when the kernel sugar concentration of the 24 genotypes were re
gressed against field emergence (r = -0.74, p < 0.0001) suggesting tha
t a negative relationship exists between kernel sugar content and swee
t corn germination and emergence in cold soils. Data on a mg/kernel ba
sis showed a significant positive correlation between kernel starch co
ntent and percentage field emergence (r = 0.63, p = 0.0008). This info
rmation is valuable to breeders and commercial growers for selection o
f superior cold tolerant genotypes.