EFFECT OF BORON DEFICIENCY UPON THE STRUCTURE OF ZEA MAYS

Abstract

IntroductionBoron is now included, by most plant physiologists, among the elements essential for the normal growth of higher plants.Until recently, most of the work has been done on the amount and habit of growth produced in many of our common plants, either by too great a quantity of boron or by a lack of it. BRENCHLEY (1) and COLLINGS (5) found boron to be toxic for both growth and germination with the concentrations which they used. Since then, by using very small amounts, BRENCH-LEY and WARINGTON (3), and others (9,10,12, 14,15, 16,18, 20,21,23, 24,26,27), have found boron to be indispensable for the normal growth of the plants used.Much less investigation has been done on the effect of boron on the internal structure of the plant. WEBBER (31) studied the effect of a toxic concentration of boron on prune, peach, and grape. She finds fewer chloroplasts in the leaves, and a disintegration of leaf tissue in the plants supplied with such a concentration. The smaller veinlets were often filled with a brown substance of gummy appearance. The petioles and midribs of prune often showed gum pockets resulting from a disintegration of the xylem elements. In shoots, the greatest injury was found in those that do not live beyond the first year. Sometimes phellogen developed beneath the necrotic tissues, often causing them to slough off. As in the leaf, gum pockets appeared both in the cortex and conducting system.

Transport of Boron by thetassel-less1Aquaporin Is Critical for Vegetative and Reproductive Development in Maize

“…Mutations in either tls1 or rte, the maize ortholog of BOR1 (Chatterjee et al, 2014), result in phenotypes similar to those observed in wild-type maize grown under B-deficient conditions (Eltinge, 1936;Struckmeyer et al, 1961;Lordkaew et al, 2011), supporting the hypothesis that tls1 and rte function in B homeostasis. The nonallelic noncomplementation exhibited by tls1/+;rte/+ plants can be interpreted as evidence that the two genes interact in the same pathway (Hawley and Gilliland, 2006;Baker and Braun, 2008).…”

“…Historically, the cellular effects of B deficiency on growth have been studied mainly in the root (Sommer and Sorokin, 1928;Eltinge, 1936;Lovatt, 1985;Shorrocks, 1997;Lordkaew et al, 2011). Research on several species, including maize, has shown that B deficiency results in impaired cell elongation and division in the meristematic tips of primary and lateral roots (Loomis and Durst, 1992;Dell and Huang, 1997;Goldbach et al, 2001;Baluška et al, 2002).…”

Effects of Boron on the Water Relations of Higher Plants

“…They concludled that their results substantiated Schmucker's hypothesis that the degree of hydration of cells is regulated by B. A number of investigators have failed to confirm this relationship (2,6,17,19,21). The positive relationship, which these latter authors observed, does not necessarily discredit Schmucker's explanation as to why pollen grains burst in a solution lacking B.…”

The Boron Efflux Transporter ROTTEN EAR Is Required for Maize Inflorescence Development and Fertility

“…For this reason, much interest has been placed on the possibility of engineering plants that can grow in conditions of boron deficiency or toxicity or on exploiting naturally occurring accessions (Miwa et al, 2006Sutton et al, 2007). A detailed account of the effects of boron deficiency in maize (Zea mays) was first reported in 1936 and described the disintegration of parenchyma cells in leaves and stems (Eltinge, 1936). In a more recent study monitoring the effects of boron deficiency during maize growth in a controlled setting, growth suppression of both male and female floral organs as well as a decrease in the quantity and the germination frequency of pollen grains were observed (Lordkaew et al, 2011).…”