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ZhaoSen Xie, Charles F. Forney, WenPing Xu, and ShiPing Wang

research was to study the effects of root restriction on the ultrastructure of phloem tissue and its surrounding parenchyma tissue of the grape berry during berry development. In this study, the ultrastructural characteristics of phloem tissue in the grape

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Shuang Han, Jiafu Jiang, Huiyun Li, Aiping Song, Sumei Chen, and Fadi Chen

et al., 2012 ), the relationship—if any exists—between photosynthesis and chloroplast ultrastructure has not been widely characterized. Phloem sieve elements are nonnucleated cells, largely controlled by their nucleolated companion cells, and their

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Cevriye Mert

sparse. Colzoni et al. (1990) described the pollen wall ultrastructure of Juglans regia and Juglans nigra . Evrenosoglu and Mısırlı (2009) determined pollen morphology and pollen size in‘Kaplan 86’ and ‘Şebin’ walnut cultivars. Luza and Polito

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Shujuan Yang, Li Peng, Han Bao, and Huiqiao Tian

crystals of calcium oxalate, but how these crystals form remains unknown ( Nakata, 2012 , 2015 ). Since then, crystals of calcium and oxalate have been reported in more than 215 plant families ( McNair, 1932 ). In this study, the ultrastructure and

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Cevriye Mert

morphology, and ultrastructure of pollen grains are of great importance in characterization of the pollen grains ( Currie et al., 1997 ; Fogle, 1977a ; Martens and Fretz, 1980 ; Mert and Soylu, 2007 ). Structural characteristics of the pollen grains of

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Hong Wang and Robert C. Herner

A study of the ultrastructure of leaf tissues of Chinese mustard shows that there is a progressive degeneration of the membrane structure of the grana of the chloroplast accompanied with the appearance of globules of lipid material and loss of chlorophyll during leaf senescence. A controlled atmosphere of 5% CO2 plus 3% O2 maintained chloroplast grana membrane structure for up to 4 weeks storage at 10°C. Both 5% CO2 (in air) and 5% CO2 plus 3% O2 maintained the highest chlorophyll content compared to 3% O2 alone or in air (control).

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Haktae Lim

We first investigated the ultrastructural changes of plastids of two fruit pigment genotypes of squash with isogenic backgrounds (YY and BB). In YY ovaries at anthesis chloroplasts contained granular osmiophilic bodies and a few thylakoids, having two features of chromoplasts and chloroplasts in the same organs. After anthesis grana structure gradually disappeared and the typical membranous chromoplasts formed at fruit maturity. On the other hand, proplastids observed in BB ovaries transformed directly into chromoplasts as fruits matured. The same fruits at different developmental stages were also used for protein analysis to provide the relationship between changes in ultrastructure and in protein profiles during plastid differentiation. SDS-PAGE showed that qualitatively similar total plasstid polypeptides for two lines at all stages of growth even though there were quantitative decreases or increases in the contents of a few polypeptides. Soluble and membrane associated proteins were extracted from total tissue of subepidermis of squash and showed remarkable differences regarding the relative amounts of many protein species from ovaries and mature fruits. Reduced amounts of the large and small subunits of RuBPCO were obvious especially in immature fruits compared with LS and SS of RuBPCO of squash leaves.

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Nenita V. Desamero and Billy B. Rhodes

Vitrification, a physiological disorder characteristic of in vitro grown plants, was observed in single-node cultures of sweet potato in mannitol-enriched medium during their second year of storage. Vitrified or vitreous sweet potato plantlets were watersoaked, translucent or glassy in appearance, with thick, swollen, leaves and stems, stunted shoot growth and poor root growth. These plantlets were not able to regenerate normal plants when transferred into fresh regeneration medium nor were they able to survive outside culture conditions.

Electron microscopy revealed changes in the ultrastructures of vitrified sweet potato plantlets. Vitrified plants had defective stomatal complex, starch grain-filled chloroplasts, disrupted cell wall, big air spaces (lacunae), high frequency of cell membrane separation from the cell wall, nuclear disintegration, and cytoplasmic disorganization. These changes in the internal structures of vitrified plants were reflected in their abnormal morphology and physiology.

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Nenita V. Desamero and Billy B. Rhodes

Vitrification, a physiological disorder characteristic of in vitro grown plants, was observed in single-node cultures of sweet potato in mannitol-enriched medium during their second year of storage. Vitrified or vitreous sweet potato plantlets were watersoaked, translucent or glassy in appearance, with thick, swollen, leaves and stems, stunted shoot growth and poor root growth. These plantlets were not able to regenerate normal plants when transferred into fresh regeneration medium nor were they able to survive outside culture conditions.

Electron microscopy revealed changes in the ultrastructures of vitrified sweet potato plantlets. Vitrified plants had defective stomatal complex, starch grain-filled chloroplasts, disrupted cell wall, big air spaces (lacunae), high frequency of cell membrane separation from the cell wall, nuclear disintegration, and cytoplasmic disorganization. These changes in the internal structures of vitrified plants were reflected in their abnormal morphology and physiology.

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Teresa Eileen Snyder-Leiby and Shixiong Wang

, moderate, and heavy crop loads were selected for evaluation of chloroplast ultrastructure. Hand thinning to reduce crop load. Trees from the Hudson Valley Laboratory were selected using the same criteria as those in the chemical thinning trials