Radicle emergence test predicts normal germination percentages of onion seed lots with different cultivars and genotypes

Abstract

Aims: To test radicle emergence count in order to predict normal germination percentages of onion lots.

Methods and Results: This work was conducted to test the potential for 2 mm radicle emergence (RE) to predict normal seed germination percentages of 20 onion seed lots. In the first stages of the study RE counts at 72, 76 and 80 h were highly predictive (p<0.001, R2=0.94-0.95) of normal germination after 12 days. In the second stage, the regression formula (y=45.9+0.52x) developed for the 80th hour radicle emergence to predict normal germination of 20 seed lots at various aging levels collected from the market. RE counts (%) of the 20 lots at 80 h were used to predicted values by using the formula. Actual normal percentages of 20 lots were determined after 12 days of germination testing. Then regression analysis was performed on both values. Results showed that predicted and actual normal germination percentages were highly related to actual normal germination percentages (R2=0.95, p<0.001). Means of the predicted (79.6%) and actual (80.4%) values were very similar. Results indicated that RE testing has a potential to estimate normal germination percentages of onion seed lots. 

Conclusions: RE count at 80h was highly related to normal germination percentages after 12 days (p<0.001, R2=0.95) in commercial onion seed lots.

Significance and Impact of the Study: RE testing can be used in the prediction of normal germination percentages of any commercial onion seed lots within a short period, rather than waiting until the final count (12 

days) in onion germination tests.

Keywords

• Germination test
• commercial onion seed lots
• seed ageing
• predicting germination

Radicle emergence test predicts normal germination percentages of onion seed lots with different cultivars and genotypes

Öz

Aims: To test radicle emergence count in order to predict normal germination percentages of onion lots.

Methods and Results: This work was conducted to test the potential for 2 mm radicle emergence (RE) to predict normal seed germination percentages of 20 onion seed lots. In the first stages of the study RE counts at 72, 76 and 80 h were highly predictive (p<0.001, R2=0.94-0.95) of normal germination after 12 days. In the second stage, the regression formula (y=45.9+0.52x) developed for the 80th hour radicle emergence to predict normal germination of 20 seed lots at various aging levels collected from the market. RE counts (%) of the 20 lots at 80 h were used to predicted values by using the formula. Actual normal percentages of 20 lots were determined after 12 days of germination testing. Then regression analysis was performed on both values. Results showed that predicted and actual normal germination percentages were highly related to actual normal germination percentages (R2=0.95, p<0.001). Means of the predicted (79.6%) and actual (80.4%) values were very similar. Results indicated that RE testing has a potential to estimate normal germination percentages of onion seed lots.

Conclusions: RE count at 80h was highly related to normal germination percentages after 12 days (p<0.001, R2=0.95) in commercial onion seed lots.

Significance and Impact of the Study: RE testing can be used in the prediction of normal germination percentages of any commercial onion seed lots within a short period, rather than waiting until the final count (12 days) in onion germination tests.

Anahtar Kelimeler

• germination test
• commercial onion seed lots
• seed ageing

Kaynakça

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