Quantitative determination of calcium oxalate and oxalate in developing seeds of soybean (Leguminosae)

Developing soybean seeds accumulate very large amounts of both soluble oxalate and insoluble crystalline calcium (Ca) oxalate. Use of two methods of detection for the determination of total, soluble, and insoluble oxalate revealed that at +16 d postfertilization, the seeds were 24% dry mass of oxalate, and three-fourths of this oxalate (18%) was bound Ca oxalate. During later seed development, the dry mass of oxalate decreased. Crystals were isolated from the seeds, and X-ray diffraction and polarizing microscopy identified them as Ca oxalate monohydrate. These crystals were a mixture of kinked and straight prismatics. Even though certain plant tissues are known to contain significant amounts of oxalate and Ca oxalate during certain periods of growth, the accumulation of oxalate during soybean seed development was surprising and raises interesting questions regarding its function

Moving carbon between spheres, the potential oxalate-carbonate pathway of Brosimum alicastrum Sw.; Moraceae.

Aims The Oxalate-Carbonate Pathway (OCP) is a biogeochemical process that transfers atmospheric CO2 into the geologic reservoir as CaCO3; however, until now all investigations on this process have focused on species with limited food benefits. This study evaluates a potential OCP associated with Brosimum alicastrum, a Neotropical species with agroforestry potential (ca. 70–200 kg-nuts yr−1), in the calcareous soils of Haiti and Mexico. Methods / results Enzymatic analysis demonstrated significant concentrations of calcium oxalate (5.97 % D.W.) were associated with B. alicastrum tissue in all sample sites. The presence of oxalotrophism was also confirmed with microbiological analyses in both countries. High concentrations of total calcium (>7 g kg−1) and lithogenic carbonate obscured the localised alkalinisation and identification of secondary carbonate associated with the OCP at most sample sites, except Ma Rouge, Haiti. Soils adjacent to subjects in Ma Rouge demonstrated an increase in pH (0.63) and CaCO3 concentration (5.9 %) that, when coupled with root-like secondary carbonate deposits in Mexico, implies that the OCP does also occur in calcareous soils. Conclusions Therefore this study confirms that the OCP also occurs in calcareous soils, adjacent to B. alicastrum, and could play a fundamental and un-accounted role in the global calcium-carbon coupled cycle

Una nova subspècie de Consolida d'Anatòlia

A new subspecies from Anatolia. Consolida hellespontica (Boiss.) Chater subsp. rosea Misirdali & Ilarslan subsp. nova, is described.[ca] Es descriu una nova subspècie d'Anatòlia, Consolida hellespontica (Boiss.) Chater subsp. rosea Misirdali & Ilarslan subsp. nov

Calcium Oxalate Crystals in Developing Seeds of Soybean

Young developing soybean seeds contain relatively large amounts of calcium oxalate (CaOx) monohydrate crystals. A test for Ca and CaOx indicated that Ca deposits and crystals initially occurred in the funiculus, where a single vascular bundle enters the seed. Crystals formed in the integuments until the embryo enlarged enough to crush the inner portion of the inner integument. Crystals then appeared in the developing cotyledon tissues and embryo axis. All crystals formed in cell vacuoles. Dense bodies and membrane complexes were evident in the funiculus. In the inner integument, cell vacuoles assumed the shape of the future crystals. This presumed predetermined crystal mould is reported here for the first time for soybean seeds. As crystals in each tissue near maturity, a wall forms around each crystal. This intracellular crystal wall becomes contiguous with the cell wall. Integument crystals remain visible until the enlarging embryo crushes the integuments; the crystals then disappear. A related study revealed that the highest percent of oxalate by dry mass was reached in the developing +16 d (post-fertilization) seeds, and then decreased during late seed maturation. At +60 d, CaOx formation and disappearance are an integral part of developing soybean seeds. Our results suggest that Ca deposits and crystals functionally serve as Ca storage for the rapidly enlarging embryos. The oxalate, derived from one or more possible metabolic pathways, could be involved in seed storage protein synthesis.This article is from Annals of Botany 88 (2001): 243, doi: 10.1006/anbo.2001.1453.</p

Genetics and Cytology of a New Male-Sterile, Female-Fertile Soybean Mutant

Mutants affecting male sterility have potential applications in breeding methodology studies and for commercialization of hybrids. Male-sterile, female-fertile soybean [Glycine max (L.) Merr.] plants were observed in an F2 entry. Our objectives were to determine the inheritance, linkage, and allelism of the A94-JB-124 male-sterile, female-fertile mutant, and to conduct a detailed comparative microscopic study of microsporogenesis and microgametogenesis of fertile and sterile plants. The A94-JB-124 male-sterile, female-fertile mutant is a single recessive gene, allelic to ms6, and is linked to the W1 (flower color locus) with 4.3 ± 0.3% recombination value based on 988 F2 plants in the couplinglinkage phase. A comparative microscopic study of microsporogenesis and microgametogeucsis of fertile and sterile plants was conducted. The expression of the male-sterile gene is associated with rapid degenerative changes both in the tapetum and the parietal layer. These changes are initiated at the late sporogenous mass stage. The A94-JB-124 mutant was assigned gene symbol Ms6 ms6 (Ames 2) and Genetic Type Collection number T354H. The T295H Ms6 ms6 mutant is now designated Ms6 ms6 (Ames 1). T354H will be useful in the Coscgregation Method to produce hybrid soybean seed.This article is from Crop Science 39 (1999): 58, doi: 10.2135/cropsci1999.0011183X003900010009x.</p