|Seed and Planting - 70
SEED SOAKING OUTMODED?
Seed-coating work continues with the hope of eliminating the cumbersome le seed-soaking operation. This work might also lead to a total new approach to seedbed preparation and stand establishment.
Materials tried for seed coating have included chemicals to protect against diseases, micronutrients to correct soil deficiencies, and growth-stimulating substances to speed seedling development. All tests in 1969 and 1970 involved various combinations. Of those tested, the most promising series involved activated charcoal. The charcoal protected significantly against damage from some of the herbicides applied to the seedbed at preplant. Additional work will be required before coated rice seeds will fit into production practices.
Coated seed could be better adapted for drill-seeding or water-seeding by air. Fungicides in the coat could save a step in application.
The work involves not only tests of various materials but the development of improved methods for coating seed.
þ DON'T DELAY SEED USE AFTER SOAKING
After a soaking bin is drained, seed temperature rises and oxygen levels decline. Low oxygen (only 1 percent of gaseous volume within 20 hours of draining) can inhibit seedling development if the seeds are left in that state for 72 hours. But even before that (48 hours after draining) the temperature in the bin gets close to the killing temperature of 105 degrees Fahrenheit.
So: plant the drained seed as soon as possible after draining is complete, preferably within 24 hours of the start of draining. If north winds or other circumstances delay seeding, reflood with cold water and redrain every 24 to 36 hours until you sow.
þ NEW RICE LINES ARE PROMISED FOR 1971 AND LATER
CS-M3, a medium grain, is now being increased under the seed certification program. Grown in 1970 were 245 acres of registered seed. By 1972 enough seed should be available for planting 150,000 acres of this new, high-yielding smooth-hull larger-seeded variety in California.
S-6183 is a promising smooth (nonpubescent) medium grain that matures about the same time as Colusa. It produces grain with a high head yield and a high mill-out.
Final evaluations are being made of many lines of pearl, medium, and long-grain rice. Seeds are being increased so they can be made available to growers as soon as possible after they prove their worth in local Extension tests.
All new potential varieties are, of course, examined as to grain quality, head yield, translucence, kernel shape, taste, texture, and freedom from white belly.
LINES TOLERANT TO LOW AIR AND WATER TEMPERATURES ARE PROGRESSING
Lines are being tested for ability to stand low air temperatures at heading without blanking. Selection against blanking involves 3,000 lines. Lines tolerant to low water temperature have been identified and crossed with adapted California varieties.