Foliar Iron Fertilization – A Critical Review

The editor version is available at: http://www.tandf.co.uk/journals/titles/01904167.aspApplication of foliar iron sprays is a common means of correcting Fe deficiency of agricultural crops. However, variable plant responses to iron sprays ranging from defoliation to no effect have been often described in the iron fertilization literature. There is still limited knowledge concerning the mechanisms of penetration of a leaf applied Fe-containing solution and the role of Fe in the leaf. The complex and multi-disciplinary character of the factors determining the effect of iron sprays hinder the development of suitable foliar fertilization strategies, applicable under variable local conditions and for different plant types. The review is directed towards describing some key factors involved on the process of penetration of a leaf applied, iron containing solution as a prior step to briefly analyze the available foliar iron fertilization literature. Iron chemistry, leaf penetration and plant nutrition principles will be merged with the aim of clarifying the constraints, opportunities and future perspectives of foliar iron sprays to cure plant Fe deficiency.Peer reviewe

The Gromov–Lawson–Chernysh surgery theorem

This is an expository article without any claim of originality. We give a complete and self-contained account of the Gromov–Lawson–Chernysh surgery theorem for positive scalar curvature metrics

Partial Clustering in Binary Two-Dimensional Colloidal Suspensions

Strongly interacting binary mixtures of superparamagnetic colloidal particles confined to a two-dimensional water-air interface are examined by theory, computer simulation and experiment. The mixture exhibits a partial clustering in equilibrium: in the voids of the matrix of unclustered big particles, the small particles form subclusters with a sponge-like topology which is accompanied by a characteristic small-wave vector peak in the small-small structure factor. This partial clustering is a general phenomenon occurring for strongly coupled negatively non-additive mixtures.Comment: 12 pages, 5 figures, submitted 200

Ultra-fast quenching of binary colloidal suspensions in an external magnetic field

An ultra-fast quench is applied to binary mixtures of superparamagnetic colloidal particles confined at a two-dimensional water-air interface by a sudden increase of an external magnetic field. This quench realizes a virtually instantaneous cooling which is impossible in molecular systems. Using real-space experiments, the relaxation behavior after the quench is explored. Local crystallites with triangular and square symmetry are formed on different time scales and the correlation peak amplitude of the small particles evolves nonmonotonically in time in agreement with Brownian dynamics computer simulations.Comment: 4 pages, 4 figure

Contents of non-structural carbohydrates in fruiting cape gooseberry (Physalis peruviana L.) plants

Although the cape gooseberry has become the second most important export fruit in Colombia, information is scarce for its carbohydrate partitioning, which plays a major role in plant productivity. Seed-propagated Colombia ecotypes were kept in a greenhouse in 2.5-L plastic containers filled with washed quartz sand and were ferti-irrigated. The plants were pruned to one main vegetative stem with two generative stems. Dry matter (DM) partitioning during the initial plant growth showed the highest accumulation rate in the roots during the first 20 days, whereas, at a later stage of development, the shoot DM gain was higher and the leaf DM gain was lower than that of the roots. Sixty days after transplant, the plant parts were quantified and analyzed for glucose, fructose, sucrose, and starch. The roots were the largest carbohydrate pool for starch, but the sucrose content was lower in the roots than in the vegetative stem and the lower part of the reproductive stems. At 5-15 cm of the vegetative stem base, 6.4 mg of starch, 1.4 mg of monosaccharides and 5.3 mg/100 g of DM sucrose were found, indicating that this lower organ is also important for starch accumulation and, especially, for sucrose transport. In the two reproductive stems, the starch contents were much higher in the base part than in the apical part; the same relationship was found in the leaves. The monosaccharide content was the highest in the apical stem position with 8.2 mg/100 g DM. In contrast, the apical-positioned 10-day-old fruits had maximum starch concentrations (11.6 mg/100 g DM), possibly due to the assimilatory starch from green fruit photosynthesis, whereas the mature basal fruits (60-day-old) mainly accumulated sucrose (25.7 mg) and monosaccharides (21.2 mg/100 g DM)

UD Gheg Pear Stories

UD Gheg Pear Stories (GPS) contains renarrations of Wallace Chafe's Pear Stories video (pearstories.org) by heritage speakers of Gheg Albanian living in Switzerland and speakers from Prishtina

Crecimiento de frutos y ramas de manzano ‘anna’ (malus domestica

Growth curves of fruits and shoots in relation to time afterfull bloom of “Anna” apple trees growth at 2470 m altitudewere determined in Paipa (Colombia). The evaluatedparameters in fruits every four days were: fresh weight,dry weight, length /diameter ratio of fruits. Shoot growthwas meassured at the same periodicity that by fruits. Theregression ecuations for evaluated parameters are reportedin this paper. The fresh weight increase of fruits wasslow until 46 days after full bloom (dafb), then it wasquickly until 62 dafb; among 62 and 74 dafb appeared aslow growth phase again; and finally, the growth intensityincreased until the ripening time. The dry weight increaseof fruits was slow until 58 dafb; and then it was quicklyuntil 94 dafb und finally decresased from 94 dafb. Thelength /diameter ratio decreased until 90 dafb and then itstabilished. Shoots grew quickly until 70 dafb, and thentheir growth intensity decreased among 70 and 94 dafb;and finally, their growth delayed from 94 dafb. With thisinformation it is possible to make a more rationale plan forsome culture activities at this apple variety cultured in theColombian highlands, that present similar agroecologicalconditions to those in which this study was done