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Control of flower initiation in the new durable poinsettia ‘Paul Mikkelsen’

by A. M. Kofranek, W. P. Hackett, R. O. Miller

Abstract

a new cultivar of poinsettia will be in plentiful supply for the 1965 holiday season in California market places. This relatively new introduction, named ‘Paul Mikkelsen’ (after the plant breeder), has outstanding keeping qualities. If placed in the north window and properly watered, it may remain attractive beyond the Easter season. This endurance is unequalled in the standard cultivars. The bracts are not as large as the older cultivars, but they have the same vivid red color. Because of its upright stem habit, stake support is not usually required (cover and photo 2).

Excess Phosphorus and Iron Chlorosis

by P. C. De Kock, A. Wallace

Abstract

High concentrations of phosphate in plants cause a typical iron deficiency chlorosis with characteristic mineral and biochemical patterns. Studies show that organic acids in leaves are involved in the absorption and distribution of minerals, particularly calcium and potassium, and that their behavior is controlled by an iron-phosphate balance.

Slab pruning: Of mature orange trees eases harvesting, reduces yields

by J. E. Pehrson, C. D. McCarty

Abstract

Training or shaping trees for easier harvesting must take into account yield reduction from pruning operations. Reshaping mature Valencia trees by slab pruning resulted in 80% less fruit, according to this report of a two-year trial conducted by the Citrus Research Center and the Agricultural Extension Service.

A progress review…: The cotton variety improvement program

by John H. Turner

Abstract

The U. S. Cotton Research Station at Shafter is the focal point for research on cotton variety improvement by USDA researchers with the cooperation of University scientists. This continually expanding research has already improved techniques for testing and seed multiplication, widened the genetic base of the material being used, increased yield and quality of Acala 4–42, and developed new Acala strains. Future basic research in genetics, breeding methodology, and gene transfer phases is aimed at reducing costs for producers and transforming California cotton fields into efficient, factory-like operations.

Extra pounds Extra quality beef…: U. C. heifer selection

by R. Helphenstine, K. Ellis

Abstract

More pounds of beef, better quality, and improved conformation have been achieved in commercial cattle herds using the Heifer Selection Program of the University of California Agricultural Extension Service. The selection program is based mainly on the inherited traits of conformation grade and postweaning gaining ability.

Propagation of california wax myrtle: …A valuable native shrub or tree for highway landscaping

by R. M. Sachs, J. Debie, R. W. Isle

Abstract

California Wax Myrtle, recently selected for testing along highways, is not propagated commercially; hence, performance trials with this species have lagged because of inadequate numbers of plants. Results of research reported here show that rooting of cuttings is greatly dependent upon the nature of the cutting material and time of year at which cuttings are taken. Up to 80% rooting has been achieved at U. C., Davis, using softwood cuttings taken in April, and applying mist-propagation techniques for two to three months. Rooting percentages are generally increased by treatment with indolebutyric acid (0.8% in a talc preparation).

Porous block mulch:

by S. J. Richards

Abstract

water evaporaiion losses from the soil surface constitute one of the inevitable inefficiencies of irrigation. Many types of soil coverings or mulches have been investigated for reducing evaporation losses. Studies have shown that a porous mulch can be made by cementing pea gravel with a small amount of fine sand and cement mortar to hold the gravel grains in a solid array without filling the pores between grains. Such a mulch has favorable characteristics not only for water conservation, but for reducing salinity hazards, preventing soil compaction and minimizing weed control. Water conservation and salinity become even more important in arid or desert areas. For ornamental plantings, such a mulch can be cast in block form for use over the soil surface much like stone or concrete blocks.

High Oleic Acid Content in New Safflower, UC-1

by P. F. Knowles, A. B. Bill, J. E. Ruckman

Abstract

basc genetic researcuh on safflower introduced to the United States from many parts of the world has turned up a gene with an unusual faculty. This gene changes the proportions of oleic and linoleic acid in the oil, and makes safflower oil chemically like olive oil. Unfortunately, the gene was found in an introduction (UC57-147) which was not suitable for commercial production in this country because of its low yield and low oil content. By crossing UC57-147 to N-10, and then backcrossing the products of the cros twice to US-10, it was possible to transfer the gene to an acceptable commercial safflower type. This type has been termed UC-1. The fatty acid composition of UC-1 and other oils may be noted in the tahle; the graph compares UC-1 with US-10 in fatty acid composition of the oil.

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Research articles

Research articles