Rye Pollen Research Articles

Grauballemandens fundsted

Grauballemandens fundsted

The relation between the age of wheat flowers and the percentage of hybrids to set in the wheat-rye crosses

1. The role of the age of wheat (Triticum vulgare) flowers in the crosses with rye (Secale cereale) pollen was studied in four wheat varieties in regard to the % of grain set, % of grain germination and the amount of the development of grains. 2. The function of ovules was kept as far as 9-13 days after the emasculation in different varieties. 3. In a tariety (Honkei No. 124) that showed low % of grain set, no difference of grain set was observed in connection with the age of flowers, while in all other three varieties, Norin No. 68, awnless Hiraki and Nisimura, a higher % of grain set was seen and a considerable diffeirence of grain set was found according to the age of flowers. 4. In Norin No. 68, awnless Hiraki and Nisimura, the germination of graihs was the highest when the flowers were pollinated 1 or 2 days after the emasculation. It became lower when the pollination was made for older flowers. 5. The weight df grain, which may show the amount of the development of grain, was the largest when the pollination was made ca. 2 days after the emasculation. 6. The percentage of the sudcess of wheat-rye crosses was highest when the wheat flowers were pollinated with rye pollen 1 or 2 days after the emasculation. 7. The most favourable age of wheat ovules in the crosses with rye pollen is 1 or 2 days after the emasculation.

On the crossability between wheat (<i>Triticum vulgare</i>) and rye (<i>Secale cereale</i>)

1. Materials used in this work are 27 varieties of wheat (T. vulgare) and 6 varieties of rye (S. cereale).2. During three years from 1945 to 1947, 44, 445 wheat flowers were pollinated with rye pollen.3. The set percentage showed a great difference from 66.3% to 2.1% according to wheat varieties, but it did not differ much in different years.4. One and the same wheat variety pollinated with 6 varieties of rye showed similar percentages in seed set.

THE CAUSES OF SELF‐STERILITY IN RYE

THE CAUSES OF SELF‐STERILITY IN RYE

The Production of Precipitins for Ragweed Pollen

Abstract It has been proved beyond question that guinea-pigs can be made hypersensitive to pollen (ragweed or rye) (1, 2, 3, 4). However, because of the failure of all workers to demonstrate precipitins to pollens, certain observers (1, 3, 5, 6) still hold that the specific hypersensitive condition brought about by the injection of pollen into guinea-pigs may not be a true anaphylactic sensitization. Although Alexander (12), in one instance, was able to transfer the hypersensitive condition to rye pollen, passively, he was unable to demonstrate precipitins in the serum of the 4 guinea-pigs tested. In this paper, we are reporting on the results of the successful production of precipitins for ragweed pollen. Experimental Method of immunization. We were entirely unsuccessful in demonstrating precipitins in the serum of 2 rabbits injected weekly for a period of over two months with a suspension or a weak alkali extract of giant ragweed pollen.

Observations on the Anaphylactogenic Properties of Rye Pollen (Secale Cereale)

Summary This paper is based upon observations made on 20 guinea-pigs to determine the anaphylactogenic properties of the pollen of rye (secale cereale). The pollen was obtained from a reliable source and microscopically showed the characteristic features of that pollen. It was extracted with a 2 per cent solution of sodium bicarbonate and the extract contained 2.01 mgm. N to 1 cc. Nine animals received only one sensitizing injection. Four animals received an initial injection of 2 cc. (4.02 mgm. N) and the same amount was repeated five days later. Five animals received an initial injection of 1 cc. (2.01 mgm. N) and a repetition of the same was given three weeks after the primary injection. While normal guinea-pigs were found to survive, and without symptoms, 2 cc. of the rye pollen extract, the sensitized guinea-pigs invariably succumbed to injection of 1 cc. of the extract (100 per cent). Of 4 animals injected with 0.75 cc. of the extract, 3 (75 per cent) succumbed within two minutes of injection exhibiting typical anaphylactic symptoms, while 1 gradually recovered following a severe anaphylactic reaction. Dosages of 0.5 cc., or less, invariably gave rise to marked anaphylactic symptoms, but the animals gradually recovered. These animals invariably showed a subsequent increase of tolerance as is evidenced by their surviving the injection of 1 cc. of the extract on the following day. Passive transfer was accomplished from the sensitized guinea-pig to a normal one. The injection of 1 cc. of the rye extract intravenously on the day following an intraperitoneal injection of 5 cc. of the sensitized animal's serum, proved fatal within two minutes.