Showing papers on "Plant physiology published in 1967"

The function of calcium in plants

Abstract: Introduction ................................................................................................................................................................................................ 407 The calcium requirement of plants ................................................................................................................................ 408 Anatomical and cytological effects of calcium deficiency ........................................................................ 410 Gross defects ................................................................................................................................................................................... 410 Cellular and subeellular effects ...................................................................................................................................... 411 Physiological and biochemical evidence for the role of calcium ................................................. 412 Cell wall ................................................................................................................................................................................................. 412 Ion absorption and membranes ...................................................................................................................................... 414 Ion absorption by whole cells ...................................................................................................................................... 414 Mitoehondria ............................................................................................................................................................................... 416 Membranes and model systems ................................................................................................................................ 417 Nucleic acids and chromosomes ...................................................................................................................................... 418 Enzyme activity .............................................................................................................................................................................. 418 Concluding discussion .................................................................................................................................................................... 420 Literature cited ....................................................................................................................................................................................... 421

Boron adsorption by plant roots

Abstract: The adsorption capacity of boron by roots of several monocotyledonous and dicotyledonous farm crops was determined. The monocots exhibited a lower capacity for boron adsorption in comparison with dicots.

Ripening tomatoes: Ethylene, oxygen, and light treatments

Abstract: Tomato fruit (Lycopersicon esculentum Mill. var. V. R. Moscow) harvested at the mature green stage were ripened by treatments with ethylene, oxygen, and oxygen plus ethylene. Treatments were made under dark and light conditions. Ethylene increased the ripening and respiration rates of the tomatoes. The fruit treated with ethylene had a general increase in beta carotene and lycopene when compared with untreated controls. The per cent acid was variable from year to year in the fruit treated with ethylene. The fruit ripened in ethylene had higher concentrations of citric acid than did the untreated controls. Treatments with oxygen decreased the reducing sugars and at the high concentrations used, had no effect on the rate of lycopene synthesis. Light treatments increased the per cent acid, reducing sugars, and color of the ripened fruit. The increase in color was related to an increase in both beta carotene and lycopene. Light treatment seemed to decrease the respiration rate of the fruit not treated with ethylene. Studies usingC14O2 showed that this may be due to utilization of CO2 evolved from respiration by the green fruit in photosynthesis.