Vergara - 1976 - Physiological and morphological adaptability of ri

STERILE-TYPE COOL INJURY 1N PADDY RICE PLANTS 295
Earlier
Intermediary
abnormalities abnormalities Suppressed
(‘out
lb in rnicrospores 1b in microspores ii pollen III-b
‘emporium’!
or tapctal cells or tapetal cells maturation
or both
or both
Amh"
indehiscence
i’ Sterility
Tape-tat/
hypertrophy
7. Causal sequence from cool temperature to sterility (Nishiytlma. 1970).
of abnormalities, and attempted to make clear the primary cause of coolinjury
sterility‘. Abnormalities that we have now clarified are as follows:
Our tibservations at anlhcsis indicated that the direct cause of cool-injury
sterility is anther indehiscence due to pollen unripeness. The decrease of anther
components such as N. P. K, amino acids, and protein, and the decline of respiratory
activity’. were recognized 4-5 days after cooling treatment. I-lovt-‘et-‘er.
these abnormalities were not recognized during cooling. They are not the
cause. but the result of cool injury.
Abnonnal symptoms in microspores were observed 3 days after the start of
cooling. On the other hand, the first symptoms of tapetal abnormality and the
abnormal increase of sucrose content of anthers were recognized on the first day
after the start of cooling. We have not elucidated the causal relationships among
the abnormalities of tapeta and microspores. and the remarkable increase of
sucrose in anthers. These relationships may suggest the future approach to
cool-injury" sterility‘.
REFERENCES
AKEMTNE. M" and Y. HOSIEIKA. 1939. The intervarietal difference and the effect of environmental
factors in respect to sterility in paddy rice [in Japanese]. Farm Special Res. Fae. Agrie.
Hokkaido Llniv. 7:l—l51.
FLUISHITA. N. 1970. Studies on the mechanism of the pollen degeneration caused by low- and
high-temperature, darkness and gametocide (l-‘W’ 450) treatments in vegetable crops |in
Japanese, with English summary]. Bull. Llniv. Osaka Prefect. Ser. B, 22:111-203.
FUKAS.~\\\"."\. H. 1954. 0n the free amino acids in anthers of male-sterile wheat and maize. Jpn.
J. Genet. 29:l35—l37.
IlAYASE, H, and T. SATAKE. 1970. Degeneration of pollen in sterility type of cool injury in rice
plants [in Japanese]. Proc. Crop Sci. Soc. Jpn. 39 (extra issue 3:93-94.
IIAYASE. H.. T. SATAKE. I. NISHlYAlvtA. and N. ITo. 1969. Male sterility caused by cooling treatment
at the meiotic stage in rice plants. II. The most sensitive stage to cooling and the lertililing
ability of pistils. Proe. Crop Sci. Soc. Jpn. 38:7U6~7ll.
HtJSUKAl-VA. S.. C. TsLrpA. and T. TAI-LEDA. 1963. Histochemical studies on the cytoplasmic
male sterility of sugar beet. with reference to the hydrogen-ion concentration. carbohydrate
and amino acids in anthers [in Japanese. “tith English summary]. Jpn. J. Breed. l3:ll7—l24.