야간 저온조건이 파프리카 화분 활력 및 생식기관 발달에 미치는 영향

Abstract

Bell pepper plants (Capsicum annuum cv. Plenty) were grown under low night temperatures (LNT: day/night temperature of 28/13℃) and optimum night temperatures (ONT: day/night temperature of 28/20℃) in growth chambers. Pollen grains were collected from plants in the growth chamber and incubated at 10, 15, 20, 25, and 30℃. After 24 hr incubation, in both ONT and LNT, the highest percent pollen germinations were observed at 25℃ followed by germinations at 30℃. Percent pollen germination at 25℃ was 42% in ONT - two times higher than in LNT at 21%. Pollen tube length was much longer at ONT than at LNT, regardless of incubation temperature. Compared with other treatments, earlier and quicker pollen tube elongation was observed in ONT pollen grains incubated at 25℃. To find pollen viability in plant growing conditions, pollen grains were incubated in LNT (28/13℃) and ONT (28/20℃) growth chambers for 24 hr. Petri-dishes with pollen grains were put in the growth chambers at the beginning of the night condition. Pollen grains in the LNT growth chamber did not germinate at night (13℃), but began to germinate when the day condition (28℃) started. Pollen grains in the ONT condition, however, started germinating from the early night (20℃) and germination continued during the day (28℃). Plants in LNT showed increased flower stalk length, ovary diameter, stamen length, flower weight, and fruit length. LNT conditions did not impair seed set. There were no differences in seed sets between fruits at LNT and ONT. Normal seed sets in LNT show that fertilization may be completed during daytime. However, further investigation is needed to find what extent of temperature stress causes malformed and/or parthen℃arpic fruits in this bell pepper.