Mechanical Conditioning for Control of Growth and Quality of Vegetable Transplants

Abstract

Physical disturbance of plants or plant parts results in a mechanical stress response from the plant. Mechanical stress applied naturally or under controlled conditions inhibits growth in mass and dimensions of major plant parts. Wind and precipitation are important natural sources of mechanical stress. Under field conditions, cultivated plants experience these natural mechanical stresses plus those caused by irrigation and contact with farm machinery or workers during cultivation. Some horticultural practices, such as staking of trees or potted plants, pinching or pruning stems, deadheading flowers, bagging potted plants, or training branches, are mechanical stresses that affect plant growth. Handling practices in plant science research, such as cross-pollination or tagging of flowers (Frizzell et al., 1960) or repeated attachment of leaf chambers for measurement of water status or photosynthetic rates (Marler and Mickelbart, 1992), also can affect plant growth and physiology.

Conditioning Treatments Affect Insect and Mite Populations on Bedding Plants in the Greenhouse

“…Herbaceous ornamentals are commonly treated with PGRs, such as daminozide, paclobutrazol, or uniconazole [(E)-1-(4chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-penten-3-ol]. Mechanical conditioning via brushing or shaking of plant shoots affects the growth and condition of a variety of vegetable transplants (Latimer, 1991) and ornamental bedding plants (Autio et al, 1994). Moisture stress conditioning (MSC), the controlled exposure of plants to nonlethal water Two irrigation treatments were included.…”

Responses of Aster, Dusty Miller, and Petunia Seedlings to Daily Exposure to Mechanical Stress

“…As shown by Heuchert and Mitchell (1983) and discussed by Latimer (1991), plant responses to MS vary with the season. In our study, petunia and dusty miller responded more readily in autumn, but aster did not.…”

“…Nonchemical growth-control methods, such as manipulating light quality, imposing daynight temperature differentials (Moe and Heins, 1989), and simulating mechanical stress (MS) (Beyl and Mitchell, 1977), may offer alternatives for growth regulation in bedding plant production. MS reduces elongation in many species (Biddington, 1986;Latimer, 1991). Using MS to control elongation of vegetable seedlings has been studied widely, and MS applied by brushing is recommended for conditioning cauliflower and broccoli (Brassica oleracea L. var.…”

Urina De Vaca E Fosfito De Cobre No Crescimento E Desenvolvimento De Mudas De Tomateiro

“…Para evitar o plantio de mudas estioladas em campo, produtores têm realizado o condicionamento do crescimento das mudas, ou seja, aplicando algum estimulo químico ou físico, ou estresse aplicado às mudas, visando regular o crescimento e a qualidade das mesmas (Latimer, 1991;Bovi e Minami, 1999). Nesse sentido, Pereira et al (2007) descrevem que mudas de tomateiro pulverizadas com produtos a base de cobre podem ter o crescimento reduzido.…”