Integrating low water potential seed hydration with other treatments to improve cold tolerance

Abstract

Matriconditioning improved the performance of pepper, tomato, sweet corn, snap bean, table beet, sugar beet and watermelon seeds in early field plantings at suboptimal temperatures (averaged over 10 d after planting) ranging from 12 to 18 °C. Reduction in the time to 50% (T(50)) emergence in conditioned seeds ranged from 0·6 d in watermelon to 3·3 d in pepper and improvement in emergence from 10% in sugar beet to 30% in table beet. Further improvement in emergence occurred by inclusion of pesticides and/or gibberellin during conditioning. A 4 d conditioning of pepper at 25 °C was superior to 7 d conditioning at 15 °C in seeds germinated at 15 °C on filter paper, but 15 °C conditioning was superior in improving percentage emergence in early field plantings. Tomato seeds conditioned at 15 or 25 °C performed equally well in the field. A 2 d conditioning was superior to 1 d conditioning in improving the performance of supersweet sweet corn cultivars grown in a growth chamber at 10/20 °C. The water uptake rate in the presence of Micro-Cel E during matriconditioning of sweet corn seeds was slower than when the seeds were exposed to the same amount of water in absence of the carrier. Electrolyte leakage was greater in supersweet 'Challenger' sweet corn seeds carrying the sh(2) gene compared to the sugary type sweet corn 'More', and in both cases matriconditioning reduced the leakage. Lettuce seeds matriconditioned for 24 h had higher 1-aminocyclopropane-l-carboxylic acid (ACC) content, developed greater ACC oxidase activity and performed better at 10 °C (germinated earlier and had higher percentage germination) than the untreated seeds. Matriconditioning appears to bring about beneficial physical, physiological and biochemical changes that seemingly improve embryo growth potential and tolerance to low temperatures.

Seed priming improves irrigation water use efficiency, yield, and yield components of late-sown wheat under limited water conditions

“…This method provides gradual, controlled hydration of seeds and avoids the development of temperature gradients in seed mass (Taylor et al 1998). Matriconditioning is shown to improve the speed of germination and germination percentage of vegetable seeds under suboptimal low temperatures (Khan et al 1992(Khan et al , 1995.…”

Value of the mucilaginous pellicle to seeds of the sand-stabilizing desert woody shrub Artemisia sphaerocephala (Asteraceae)

“…Whereas dew and small rains are not sufficient to engender germination (Huang and Gutterman 1999) they may be sufficient to provide a priming effect for the embryo (Heydecker et al 1973;Bewley and Black 1982;Khan et al 1995). This includes the re-establishment of cell membranes (Leprince et al 1993), and the rapid (within 1-3 h) repair and restoration of DNA integrity (Cheah and Osborne 1978;Elder and Osborne 1993;Boubriak et al 1997;Osborne 2000).…”

Can Solid Matrix Priming With GA3 Break Seed Dormancy in Eastern Gamagrass?

“…Because removal of the eastern gamagrass cupule risks the integrity of the caryopsis, it is necessary to find a method of increasing the germination of intact seeds. GA3 could be incorporated into solid matrix priming systems, which control the rate and level of seed hydration through osmotic or matric forces of water potential (Khan 1992;Khan et al 1995;Taylor et al 1998).…”