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1

The structural changes of lignin at different stages of growth of Napier grass

100%

Zhou X. F.

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2017

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tom vol. 60, nr 199

37--45

EN

The aim of this study was to investigate the lignin composition and structure during Napier grass growth. Napier grass showed an increase in lignin, xylan, glucan content and a decrease in acetone extractives and ash content with its growth, while the content of cellulose and holocellulose reached the highest value after four months growth. In addition, milled-wood lignins (MWL) isolated from Napier grass were characterized with 2D-NMR and Py-GC-MS. The results obtained showed that GSH-type substructures were included in Napier grass lignin, whereas the S-G ratio decreased and the abundance of H-substructures increased during lignification. H-units were deposited at the earlier stages, whereas Napier grass was enriched in G-lignin during the late lignification, and S-units were reduced at the final stage. The differences in deposition of lignin units influenced the distribution of the different linkages of lignin units during Napier grass growth. All lignin samples showed the most abundant β-O-4', β-β' resinol linkages, whereas the data obtained by 2D-NMR indicated the similar development in GSH-type substructures with by Py-GC-MS during all stages of lignification.

2

Leaf architecture, lignification, and tensile strength during vegetative phase change in Zea mays

72%

Balsamo R. A. , Orkwiszewski J. A. J.

Acta Societatis Botanicorum Poloniae

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2008

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tom 77

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nr 3

181-188

EN

Background and Aims: Leaf morphology, anatomy, degree of lignification, and tensile strength were studied during vegetative phase change in an inbred line of Zea mays (OH43 x W23) to determine factors that influence mechanical properties during development. Methods: Tensometer, light microscopy, histochemistry. Key results: Mature leaf length increased linearly with plant development, peaked at leaves 7 and 8 (corresponding to the onset of the adult phase) and then declined. Leaf width was stable for leaves 1 through 3, increased to leaf 7, remained stable to leaf 10, and then declined through leaf 13. Lamina thickness was highest for leaf 1 and decreased throughout development. Leaf failure load to width ratio and failure load to thickness ratio increased with development suggesting that changes in leaf morphology during development do not entirely account for increases in failure load. Histochemical analyses revealed that leaf tensile strength correlates with percent lignification and the onset of anatomical adult features at various developmental stages. Conclusions: These data demonstrate that in Zea mays lignification of the midrib parenchyma and epidermis may be directly correlated with increased tensile strength associated with phase change from juvenility to adulthood. Failure load and resultant tensile strength values are primarily determined by the percent tissue lignification and the appearance of leaf architectural characters that are associated with the transition from the juvenile to the adult phase. Increased mechanical stability that occurs during the phase transition from juvenility to adulthood may signify a fundamental change in strategy for an individual plant from rapid growth (survival) to reproduction.

3

Anatomical study on the developing pericarp of selected Rosa species (Rosaceae)

58%

Guzicka M. , Zielinski J. , Tomaszewski D. , Gawlak M.

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2012

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tom 68

EN

Results of anatomical studies on the developing pericarp of selected wild roses are presented. Using SEM and CLSM, the changes in the pericarp structure of 5 species have been observed during its formation, from the flowering stage to fully ripe achenes. In the morphological development of the pericarp of Rosa species two main phases can be distinguished: the phase of intensive growth of the pericarp during which the fruit achieves its final shape and volume, and the subsequent phase of pericarp ripening when no significant morphological changes in the pericarp occur. Similarly, in the process of the anatomical development of the pericarp two phases are noticeable, however, during both stages, great internal changes proceed in the fruit. The first phase consists of intensive cell divisions and enlargement, gradual thickening of cell walls and formation of all pericarp layers. Due to these changes, the pericarp achieves its final anatomical structure. The second phase, involving the pericarp ripening, is manifested in the modification of cell walls, mainly by their quick thickening, but first of all by their lignification. The lignification of pericarp cell walls begins in the inner endocarp; it proceeds in the outer endocarp, later in mesocarp and finishes in the hypodermal cells of the exocarp. The epidermal cells remain alive the longest and their walls do not (or hardly) become lignified. The death of all cells finishes the pericarp ripening.

4

Nutritional value of red clover (Trifolium pratense L.) and birdsfoot trefoil (Lotus corniculatus L.) harvested in different maturity stages

58%

Wróbel B. , Zielewicz W.

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2019

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tom Vol. 64, nr 4

14--19

EN

During the years 2014-2015, herbage samples of red clover (Trifolium pratense L.) variety Chlumecky and birdsfoot trefoil (Lotus corniculatus L.) variety Leo were harvested at weekly intervals on 9 occasions from late April to late June. Effects of legume plant species and date of harvest on crude protein (CP), water soluble carbohydrates (WSC), neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin (ADL) and dry matter digestibility (DDM) were studied. Regardless of the date of harvest birdsfoot trefoil contained more crude protein, NDF and ADF fraction than red clover. Red clover contained more WSC. Crude protein concentration and DDM declined and WSC, NDF, ADF and ADL increased with advancing maturity of both legume species. But the rate of NDF increase with maturity in red clover was slower.

PL

W latach 2014-2015, co tydzień, dziewięciokrotnie, od końca kwietnia do końca czerwca, pobierano próbki roślin dwóch gatunków: koniczyny łąkowej (Trifolium pratense L.) odmiany Chlumecky i komonicy zwyczajnej (Lotus corniculatus L.) odmiany Leo. Badano wpływ gatunku rośliny bobowatej i terminu zbioru na zawartość białka ogólnego (CP), cukrów rozpuszczalnych (WSC), neutralnego włókna detergentowego (NDF), kwaśnego włókna detergentowego (ADF), lignin (ADL) i strawność suchej masy (DDM). Niezależnie od terminu zbioru komonica zwyczajna zawierała więcej białka ogólnego oraz frakcji włókna NDF i ADF niż koniczyna łąkowa. Koniczyna łąkowa zawierała więcej cukrów rozpuszczalnych. Wraz z postępem faz rozwojowych obu gatunków roślin zawartość białka ogólnego i strawność suchej masy malała, a zawartość WSC, NDF, ADF i ADL rosła. Jednak tempo wzrostu zawartości NDF w koniczynie łąkowej było mniejsze.

5

Structure, function and metabolism of plant cell wall

58%

Kaczkowski J.

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nr 3