Lemon Juice: Canned lemon juice contains 2.4% sugar by weight (24 grams per liter). A high concentration of sugar reduces the availability of water to the seed. If the seed cannot absorb water, it cannot germinate. Sugars can also promote microbe growth. Microbes produce waste products that can be toxic to plants.
Orange juice: Orange juice does have an effect on plants. It will increase the calcium deposits in the plant itself. This will cause the plant to grow thicker, but it won't grow as tall. So depending on what you want, orange juice could be a useful substance in growing plants.
Soda Water: If plants are fed with soda water for a period of time then it should grow faster than plants given regular tap water. This is because most plants absorb nutrients dissolved in water through their roots. Soda water contains macronutrients essential to plant growth. Those macronutrients are: carbon, oxygen, hydrogen, phosphorous, potassium, sulfur, and sodium. Given proper nutrients, plants should grow at a faster rate than those who do not acquire as much of the nutrients.