**Characterization of Genotype by Planting Date Effects on Runner-Type Peanut Seed Germination and Vigor Response to Temperature on Runner-Type Peanut Seed Germination and Vigor Response to Temperature**

**Characterization of Genotype by Planting Date Effects** 

DOI: 10.5772/intechopen.70584

Timothy L. Grey, Charles Y. Chen, Russell Nuti, Walter Scott Monfort and George Cutts III Walter Scott Monfort and George Cutts III Additional information is available at the end of the chapter

Timothy L. Grey, Charles Y. Chen, Russell Nuti,

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.70584

#### **Abstract**

Experiments evaluated the genotype by environment effects on seed germination and vigor of the peanut runner-type cultivars 'Georgia Green', 'AT3085R0', 'AT271516', 'Georgia 03L', and 'FR458' grown under similar production practices, for three planting dates: April, May, and June in Georgia and Alabama. Objectives were to determine if time of planting and harvest dates would subsequently affect germination and vigor when tested using a thermal gradient devise (temperature range14 to 35 °C). Runner-type peanut seed grown in Dawson Georgia in 2008 had the strongest seed vigor with Germ80 of 22 to 40 growing degree days (GDD), and maximum incidence of germination rate 84.8-95.7% when planted April, May, and June 2008 across 15 seed lots. In contrast, seed harvested from plantings of May 2009 at Dawson Georgia exhibited Germ80 of 24 to 40 GDD with maximum incidence of germination rate 79.8-93.6%, but seed from April 2009 plantings had poor vigor of 56.8-72.8% and no amount of GDD could achieve Germ80, with similar results for June 2009 plantings for this location. For Headland April, May, and June 2009 plantings of the same cultivars, all seed had poor vigor, ≤75.6% maximum incidence for germination rate, and none obtained a measurable Germ80.

**Keywords:** *Arachis hypogaea*, germination, genotype, phenological development, thermal time
