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- Author or Editor: H. Tiessen x
Growth of direct seeded ‘Fireball’ tomato plants was accelerated by both wax and polyethylene coating on paper mulches. Mulching increased no. of clusters, flowers, fruit per plant, and earliness. Polyethylene coating hastened growth and development more than wax coating.
The effectiveness of polyethylene-coated paper mulches in altering soil environment was investigated. The increase in maximum daily soil temperatures under mulch compared to bare soil was approximately the same for a clear polyethylene laminated on black paper as the clear polyethylene alone. Minimum daily soil temperatures were higher under laminated paper mulch than under black polyethylene. Polyethylene coated paper was as effective as polyethylene in reducing soil moisture evaporation. Studies of bulk density indicated that soils under all mulches were less compacted than the bare soil. Nitrate N levels under mulches were also higher than in the bare soil. The disposal problem encountered with polyethylene mulches at the end of the growing season is eliminated by the use of polyethylene coated paper mulches because the very thin coating of polyethylene disintegrates during the growing season, and the residual paper decomposes in the soil after tilling.
Pepper seedlings, cv. ‘California Wonder’, were exposed for 25 days to a 17 hr photoperiod at a light intensity of 800 to 1600 ft-c and a night temperature of 12 or 18°C. The treatments were initiated when the third, fourth, of fifth true leaf was 1 cm long.
More flowers were produced, as a result of increased branching, on plants exposed to the low temperature (12°) or low light intensity (800 ft-c). The response to the temperature and light treatments was greater if the treatment was initiated when the third true leaf was 1 cm long. The low temperature increased the number of days to first anthesis and decreased the number of nodes to the first flower, while light intensity had no influence on either the time of flowering or number of nodes to the first flower.
Increasing the concentration of sucrose in media containing 5 μm ancymidol increased rooting, with about 95% rooting of two asparagus (Asparagus officinalis L.) selections (Guelph-97, ‘Jersey Centennial’) obtained with 7% sucrose. In the absence of ancymidol, there was no evidence that increased sucrose concentration increased rooting. The increased rooting was not due to an osmotic effect, since the replacement of sucrose by an equimolar concentration of mannitol did not improve rooting. Chemical names used; 1-naphthaleneacetic acid (NAA), N-(2-furanylmethyl)-1H-purin-6-amine (kinetin), and α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol).
Coincident with the world food shortage, ever-increasing food prices and the shortage and high and rising costs of energy, attention is now being directed to the energy-efficiency of agricultural production (1, 5, 6, 12, 13, 18, 30, 31, 34, 40, 45, 47, 48, 52). Although the energy used annually for agriculture in the United States (48) and Canada is not a large percentage of the national totals some feel that to ensure energy supplies “agriculture must stake a claim” (27). The “claim” must stress the form of energy because current agricultural technology is so dependent on liquid fuels for machinery operation and natural gas for the production of nitrogen fertilizers (40). As an important segment of the agricultural industry, horticulturists must also “stake a claim” to energy if they believe fruits and vegetables make a legitimate contribution to food supplies. Fruit and vegetable production is considered energy-extravagant because of the high energy inputs needed compared to the usable energy output (13, 47), although few studies of the energy relationships of individual horticultural crops have been reported. Presented herein are energy calculations for the production of some fruits and vegetables for which production data in Ontario are available with a discussion of the place of fruits and vegetables in a food supply system and the flaws inherent in judging production efficiency solely on an energy basis.