Salt priming of muskmelon seeds for low-temperature germination

Abstract

“Persia 202”, a muskmelon ( Cucumis melo L.) of Iranian origin, germinated well at 12–14°C. In contrast, the Israeli cultivar ‘Noy Yizre'el’ did not germinate at temperatures below 15°C. Both “Persia 202” and ‘Noy Yizre'el’ were subjected to salt priming pre-treatments in an attempt to improve their germinability at sub-optimal temperatures. Priming in 2–3% solutions of KH 2PO 4 + KNO 3 (1:1) for 1–5 days significantly increased the germination rate, synchronization and percentage. Enhancement of these effects was greatest at 10–11°C for “Persia 202” and at 15–16°C for ‘Noy Yizre'el’. Dehydration of seeds following treatments resulted in partial reversion of the positive effects of priming if incubation took place at the lower temperatures. Storage of dried primed seeds for up to 28 days at 10°C and 45% relative humidity further reversed the beneficial effects of priming in ‘Noy Yizre'el’ but not in “Persia 202”. Nitrate-containing salts were more efficient than nitrate-free salts in promoting low-temperature germination.