Effect of harvest time, drying technique, temperature and light on the germination of quinoa (Chenopodium quinoa)

The influence of light, temperature and dry matter content of seeds on germ ination in quinoa (Chenopodium quinoa Willd.) was investigated under labora tory conditions, using seed harvested at weekly intervals over seven weeks. Light had no influence either on the germination rate or final germination . The number of seeds which germinated was affected significantly by harves t time, moisture content of the seed at harvest and germination temperature . At higher temperatures seeds germinated rapidly regardless of harvest tim e and moisture content of the seed at harvest, so that at 20 degrees C aver age germination was 99%, while at 10 degrees C average germination was redu ced to 85%. Lowering the temperature to 6 degrees C reduced average germina tion to 25%, but at this temperature an interaction with harvest date was r ecorded, so that delaying harvest increased final germination. No significa nt difference was detected between germination rate at 6 and 10 degrees C. Time to 50% germination was 2.1, 3.9 and 4.1 days, and maximum increase in germination per day was 11.1, 3.9 and 3.3% at 20, 10 and 6 degrees C, respe ctively. Drying seeds after harvest at 35 degrees C resulted in 2% higher g ermination than drying at 25 degrees C. It is recommended that quinoa is so wn when the soil temperature is 8-10 degrees C. To obtain laboratory germin ation comparable to field germination, tests should be conducted at 6 or 10 degrees C as differences in seed quality, which are important in the field , are not revealed at 20 degrees C.