Aim. The aim of this work was to determine the longevity of durum wheat seeds according to the results of seed germination monitoring after seed storage for up to 19 years under controlled conditions in the National Plant Gene Bank of Ukraine. Results and Discussion. 36 accessions of spring durum wheat were investigated. These accessions belonged to var. hordeiforme, var. leucurum, var. melanopus, var. alexandrinum, var. apulicum, var. australe from seven countries; seven samples of durum winter wheat belonged to var. hordeiforme, var. leucurum were from Ukraine. Accessions were received by the Ukrainian genebank from seven countries: Ukraine, Russia, Mexico, France, Portugal, Kazakhstan and Tunisia. Seed accessions for storage were grown mainly in the eastern forest-steppe of Ukraine, stored in the National depositary in this region at unregulated temperature and at 4°C with seed moisture content of 5.5-8.0%. The mode of seed drying, which took place at temperature not higher than 25°C is discussed. The obtained results indicate high seed longevity of durum wheat under these conditions with initial seed germination rate more than 90% even in a storage facility at unregulated temperature. There were no differences in seed longevity between varieties of durum wheat under the studied storage conditions. Conclusions. Seeds of durum wheat remain unchanged for at least 10 years with a high initial germination of seeds, storage in sealed containers with moisture content 5.5-8.0% even at unregulated temperature of the eastern forest-steppe of Ukraine. Durum wheat seeds should be storage at temperature 4°C to increase seed longevity at seed moisture 5.5-8.0%.

The Aim is to determine effect of hulls presence on hulled wheats seeds on their longevity. Results and discussion. In representatives of hulled wheat species T. monococcum, T. dicoccum cv. Polba 3 and T. spelta cv. Frankenkorn, the seeds with removed hulls had in the control and experimental variants higher germination energy and germination level than the seeds in hulls. In the control variant, the positive reaction to the removal of hulls from the seeds in diploid species T. monococcum was more significant (germination energy and germination level increased respectively by 22% and 13%), than the samples of polyploid species T. dicoccum and T. spelta (increase by 3% – 10%). Under accelerated aging, on the contrary, removal of the hulls had a stronger positive effect in the polyploid species (the increase was from 21.7% to 34.0%) than on the diploid species (the increase was by 2% and 12%). Removing the hulls from the grains of the hulled wheats accessions ambiguously affected the length of the primary roots and leaves. In the control variant, in T. monococcum, length of the primary roots in the dehulled seeds did not change compared to the undehulled seeds; in the emmer and spelt it decreased. Under the conditions of accelerated aging, removal of the hulls affected the length of the primary roots in einkorn negatively, in the emmer and spelt – there was no impact. In most cases, removal of hulls had a positive effect on the primary leaf length, with the exception of the emmer variety Polba 3 in the control – decrease by 1,5%). The possible connection of this phenomenon with the presence of inhibitors in wheat hulls established by researchers is discussed. Conclusions. In the representatives of hulled wheat species T. monococcum, T. dicoccum Polba 3 and T. spelta Frankenkorn, the seeds freed from hulls are more longevous than the seeds in hulls.

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Viability of rice (Orysa sativa L.) seeds accessions: subsp. japonica: var. italica, var. nigro-apiculata, var. subvulgaris; subsp. indica, var. mutica and var. fortuna was analised. The seed accessions were grown in the southern steppe of Ukraine and then stored at 4°C and −20°C. According to the research results, it is established that rice seeds in favorable cultivation years are able to maintain the original germination without significant changes for 10 years and longer with 6-8% moisture content even at 4°C storage temperature. There were no differences of rice seeds longevity of the same accessions stored at 4°C and −20°C. Differences of rice seed longevity of subsp. japonica and subsp. indica are discussed.

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