Effects of boron and para-hydroxybenzoic acid (pHBA) on velvetleaf.The allelochemical pHBA potentially inhibits plant growth by disturbing membrane functions. Greenhouse growth studies were conducted to determine if pHBA levels near the growth-inhibition threshold altered mineral content of velvetleaf (Abutilon abutilon (əbyt`əlŏn): see mallow. theophrasti Medic.) tissue, and if the level of available boron (B) modified pHBA effects. Seedlings were grown 3-4 weeks in nutrient solution using a randomized ran·dom·ize
tr.v. ran·dom·ized, ran·dom·iz·ing, ran·dom·iz·es
To make random in arrangement, especially in order to control the variables in an experiment. factorial factorial
For any whole number, the product of all the counting numbers up to and including itself. It is indicated with an exclamation point: 4! (read “four factorial”) is 1 × 2 × 3 × 4 = 24. experimental design. Trial 1 had crossed treatments of zero, 250, and 500[micro]M pHBA and 1, 10, and 50[micro]M B. Trials 2 and 3 added 100[micro]M B treatments, and the growth media pH was adjusted to 5.5 and aerated aer·ate
tr.v. aer·at·ed, aer·at·ing, aer·ates
1. To supply with air or expose to the circulation of air: aerate soil.
2. . Trail 1 plants in 1[micro]M B and 500[micro]M pHBA had reduced root, shoot, and leaf dry weights and leaf area. The pHBA*B interaction was significant on growth. In subsequent trials, 1[micro]M B levels reduced growth in pHBA-treated plants. Compared to 10[micro]M B controls, leaf B content was significantly lower in plants grown in 1[micro]M B, and higher in the 100[micro]M B media. Plants grown with 500[micro]M pHBA had elevated K, Mg, Mn and P leaf content (ppm), but there were no effects on Fe and Ca. Light and temperature growth variations between trials affected the pHBA inhibition threshold. The data was inconclusive regarding B augmentation overcoming allelopathic effects of pHBA.
* Remley, M.A. and F.A. Einhellig. Departments of Agriculture and Biology, Southwest Missouri State University Missouri State University is a state university located in Springfield, Missouri. It is the state's second largest university in student enrollment, second only to the University of Missouri. From 1972 to 2005, Missouri State was known as Southwest Missouri State University. .