Isolated leaf cells

Mbaku, S. B., Fritz, G. J., and Bowes, G. 1978. Photosynthetics and carbohydrate metabolism in isolated leaf cells of Digitaria pentzii. Plant Physiol. 62, 510-515. 

Mode of action studies on isolated leaf cells and chloroplasts (De Villiers et ai,... 

From these examples it is clear that a universal pre-screen cannot be developed using tissue in one growth phase alone. Indeed, systems utilizing isolated leaf cells (A or protoplasts incapable of division, will miss many herbicides. The advantage of in vitro mlnlplant systems such as duckweeds is that the plants contain both dividing and stationary cells. 

Mersie W, Singh M (1993) Phenolic acids affect photosynthesis and protein synthesis by isolated leaf cells of velvet-leaf. J Chem Ecol 19 1293... 

As with animal and human studies, isolated plant cell data cannot always be extrapolated to the whole plant or organ. The data of St John et al [239] on isolated leaf cell permeability changes following surfactant contact cannot necessarily be interpreted for the whole system as the significance of the effects depend on the ability of the surfactant to penetrate the leaf surface to affect cells inside the leaf Some of the results on isolated cells are shown in Table 10.27. 

More recent approaches [42], based on studies with isolated leaf cuticles in vitro with a wide range of formulations, considered transport through the cuticle to be a three stage diffusion mechanism, namely absorption into the cuticle, diffusion through the cuticle and finally desoiption from the cuticle into the internal leaf cells. This experimental method used a constant cuticular area, constantly covered by a volume of spray solution, so variable spreading was not an issue. An alternate version of this approach uses droplets applied to cuticular membranes which is more realistic [43]. The modified Pick s equation used in these in vitro studies [41,42] has the following form ... 

In green algae and in leaf cells of higher plants, ADP-Glc PPase has been demonstrated to reside in the chloroplast (82). More recently, using plastids isolated from maize and barley endosperm (83-85), the existence of two ADP-Glc PPases, a plastidial form, and a major cytosolic form were found. Subsequently, cytosolic forms of ADP-glucose pyrophosphorylase have been found in wheat (86, 87) and rice (88). Because starch synthesis occurs in plastids, it was proposed that in cereal endosperms, synthesis of ADP-Glc in the cytosol requires the involvement of an ADP-Glc carrier in the amyloplast envelope (85). Subsequently, characterization of the ADP-Glc transporter has been reported for maize endosperm (89, 90), barley endosperm (91), and wheat endosperm (92). 

In wheat and in quackgrass, however, glyphosate was shown to affect photosynthesis much earlier and more severely than respiration in leaf tissues (17), Brecke and Duke (99) found no effect on O2 consumption by isolated bean cells. 

In an attempt to overcome some of the problems presented by intact leaf tissue Ito et al. (1978) isolated spinach leaf cells and followed the incorpora-ti(Mi of [ N]ammonia over a period of 0.5 to 8 min in light and dark. The results showed that the label was primarily incorporated into the amide... 

Fig. 2. The assimilation of ammonia by isolated spinach leaf cells in light and dark, (a) Time course of N incorporation from [ N]H< into the amide N of glutamine (O) the amino N of glutamate ( ) and the amino N of glutamine ( ). (b) Incorporation of N from [ N]H4 into aspartate, glutamate and glutamine in the light for I min and thereafter in either light (open symbols) or dark (solid symbols). (Redrawn from Ito et al., 1978.)...

Useful progress has been made in the genetics of GAs, ABA and, more recently, ethylene [11]. However, relatively few mutations have been reported involving auxins or cytokinins. Both recessive and dominant mutants have been isolated with increased resistance to synthetic auxins [8, 14, 16], and two mutants have been described with significantly altered levels of lAA or lAA conjugates [20, 22]. Mutations have been reported that affect the cytokinin requirement of tobacco leaf cells in culture [15], and cytokinin resistance and production in the moss Phys-comitrella patens [23]. 

These are the facts which point to RNA being the template on which the synthesis of proteins takes place. Another confirmation has been brought by experiments showing that the isolated nucleic acid of tobacco mosaic virus can introduce the disease into a leaf cell as well as the whole nucleoprotein of the virus. 

Burris,R.H. Organic acids in plant metabolism. Ann. Rev. Plant Physiol. 4, 91-114 (1953) Buser,Ch., Matile,Ph. Malic acid in vacuoles isolated from Bryophyllum leaf cells. Z. Pflanzenphysiol. 82,462-A66 (1977)... 

A wide number of proteia sources are available for use ia dairy substitutes. These iaclude animal proteias, ie, skim milk ia Hquid, coadeased, or dry form (filled products) caseia, caseiaates, and coprecipitates whey proteias oil-seed proteias, fish proteias and blood proteias. Oil-seed proteia sources iaclude soybean proteia coaceatrates and isolates, groundnut proteia, cottoaseed proteia, and sunflower seed, rapeseed, coconut, and sesame seed proteias (see Soybeans AND other oil seed). Other sources are leaf and single-cell proteias (see Foods, nonconventional). Of these proteia sources, milk and soybean proteias are most widely used. Proteia usage is based oa economics, flavor, fuactioaahty, and availabiUty. 

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