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Previous work on alfalfa seeds has illustrated the close association between the rate of germination and vigour. This study examined single early counts of radicle emergence (RE) as an indirect method to measure the rate of germination in alfalfa, and investigated cell cycle activities in the early stages of imbibition. The 6-hour interval counts of just germination (JG) and germination percentages (G) of 14 seed lots at 20, 17, 15 and 13°C were compared with final emergence and mean emergence time. Single counts of JG and G were strongly correlated with mean just germination time (MJGT), mean germination time (MGT) (P < 0.01) and field performance. The results indicate that single counts of RE after 24 hours at 20°C could be used to predic the vigour of alfalfa seeds. The embryo root tip cells of six seed lots with low, medium and high vigour were used for analysis of DNA replication by flow cytometry 3, 6, 12, 18 and 24 hours after imbibition. The 4C/2C ratio 18 hours after imbibition and the increase in 4C/2C ratio between 6 and 12 hours after imbibition was associated with the vigour of the seed lot and has the potential to predict seed vigour.

Transplanting is a useful technique to produce sugar beet (Beta vulgaris L.) in arid and semi‐arid regions that face water scarcity and salinity. The major challenge in transplanting is to improve the economic benefits that smallholder farmers have in the self‐production of transplants. The objective of this study was to evaluate the yield, quality, and water use efficiency (WUE) of sugar beet in response to transplanting and different options in transplant production process. Two field experiments were conducted at two sites. The first experiment investigated the effects of seedling age at transplanting, volume of the substrate, and transplanting date. The second experiment investigated the effects of substrate media and transplant production conditions on sugar beet yield and quality. In both experiments, transplanting was compared to the direct seeding on the conventional planting date at both sites. The highest white sugar content (12.1% and 13.5%) and white sugar yield (10.2 and 12.1 t ha−1) were obtained from plants transplanted in mid‐May at sites 1 and 2, respectively. Also, root yield, total sugar content, and WUE were higher in transplanting than direct seeding. The 40‐day‐old transplants produced in 22 mL cell volume when transferred to the field in mid‐May had higher WUE than the direct seeding. The transplants produced outside the greenhouse (uncontrolled conditions) had nearly the same yields as those produced inside a greenhouse under controlled conditions. We suggest that using readily available substrates and not requiring greenhouse conditions for transplant production is a cost‐effective way for smallholder farmers to produce their own seedlings.