Maturing yellow lupin seeds were desiccation tolerant. Glucose, sucrose and cyclitols (mainly D-pinitol, D-chiro-inositol and myo-inositol) were predominant at the early stages of seed growth. Accumulation of the raffinose family oligosaccharides (RFOs) and the galactosyl cyclitols including galactinol, digalactosyl myo-inositol, galactopinitol A, galactopinitol B, trigalactopinitol A, ciceritol, fagopyritol B1 and fagopyritol B2 appeared during seed maturation; their increase correlated with seed germinability after desiccation. The loss of desiccation tolerance after seed germination was also studied. For the desiccation tolerance test, intact seedlings were dried rapidly or slowly followed by rehydration. Soluble carbohydrates were assayed before and after drying. Root tissues were more sensitive to desiccation than hypocotyl tissues and completely lost desiccation tolerance within 36 h of imbibition after both fast and slow-drying treatments. Survival of hypocotyls decreased gradually up to 96 h after imbibition. Loss of RFOs and galactosyl cyclitols in axis tissues preceded visible germination. Loss of desiccation tolerance was accompanied by loss of RFOs and galactosyl cyclitols and an increase in reducing sugars in cotyledon, hypocotyl and radicle tissues. Drying did not induce the accumulation of RFOs and galactosyl cyclitols in seedling tissues.

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The pea aphid, Acyrthosiphon pisum Harris (Homoptera: Aphididae), fed, developed, and reproduced on yellow lupine, Lupinus luteus L. (Fabaceae: Genisteae). No clear preferences for any variety within L. luteus were found. Acyrthosiphon pisum showed negative values of relative growth rate and no aphid completed development on any variety of narrow-leaf lupine Lupinus angustifolius L. Aphids did not ingest phloem sap while probing on L. angustifolius and the probes were very short. All varieties of L. angustifolius were rejected by aphids during an early stage of probing in peripheral tissues, that is, epidermis or mesophyll. There were qualitative and quantitative differences in alkaloid and soluble sugar content between the two lupine species. Within species, the relative content of individual compounds differed among the varieties. Lupinus angustifolius contained four quinolizidine alkaloids (13-hydroxylupanine, dehydrolupanine, lupanine, and angustifoline), while L. luteus contained two (lupanine and sparteine). Lupanine occurred in all varieties of both lupine species. The total content of soluble carbohydrates was similar in L. luteus and L. angustifolius . The following cyclitols were found in both lupine species: myo -inositol, D-ononitol, and D-pinitol. Lupinus angustifolius also contained D-chiro -inositol. The study of aphid probing behaviour, development, and reproduction demonstrated that L. luteus is a suitable host plant for A. pisum while L. angustifolius is not. It is likely that the rejection of L. angustifolius by A. pisum was caused by chemical factors detected by aphids at the epidermis and mesophyll level.

Soluble sugars and atulence-producing oligosaccharides in maturing yellow lupin ( Lupinus luteus L.) seedsRyszard Link to this article: http://journals.cambridge.org/abstract_S0960258500003524How to cite this article: Ryszard J. Górecki, Agnieszka Piotrowicz-Cieślak and Ralph L. Obendorf (1997). Soluble sugars and atulence-producing oligosaccharides in maturing yellow lupin ( Lupinus luteus L.) seeds. AbstractThe flatulence-producing soluble oligosaccharides are an important component of lupin seeds and were assayed to establish the pattern of their accumulation in relation to germinability during seed development and maturation. Maturing yellow lupin cv. Juno seeds were harvested at 5-day intervals from 15 to 45 days after flowering (DAF). Seed fresh mass increased to a maximum at 35 DAF followed by a decrease when axis and cotyledon tissues changed colour from green to yellow. Maximum seed fresh mass corresponded to the maximum seed size. Seed dry mass continuously increased until 40 DAF. About 75% of mature seed dry mass was in cotyledons, 22% in testa, and 3% in axis. Maximum seed germinability occurred at 45 DAF after maximum seed dry mass and desiccation. Maturing yellow lupin seeds were desiccation tolerant. Mature dry seeds contained 10.9% oligosaccharides and 1.5% sucrose. During seed growth stachyose accumulation preceded accumulation of raffinose and verbascose. The highest rate of ohgosaccharide accumulation appeared during seed desiccation and correlated with the acquisition of the ability to germinate. The sucrose :oligosaccharide ratio continuously decreased reaching 0.13 in mature seeds. Accumulation of oligosaccharides in maturing yellow lupin seeds is associated with seed germinability and seed desiccation tolerance.

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