Efficient Production of Doubled Haploids as Isogenic Line Founders via Double Heat Shock Treatment in Willow Gudgeon (Gnathopogon caerulescens)

Table 5

Cytological stage immediately before the heat shock treatment.

	Time from insemination to the start of HST (min)		Z (%)	1st cell cycle (%)
				P	PM		M	A		T
	1st	2nd			E	L		E	L
Exp. I	Immediately before HST1
	23	—	13 (86.7)	2 (13.3)
	25	—	6 (66.7)	2 (22.2)	1 (11.1)
	27	—	3 (27.3)	5 (45.5)	3 (27.3)
	29	—	1 (10.0)	7 (70.0)	1 (10.0)	1 (10.0)
	31	—		6 (66.7)	2 (22.2)	1 (11.1)
	Immediately before HST2
	23	39	4 (33.3)	5 (41.7)	3 (25.0)
	25	41	3 (27.2)	4 (36.3)	3 (27.2)	1 (9.0)
	27	43		1 (7.7)	8 (61.5)	4 (30.8)
	29	45		1 (10.0)	6 (60.0)	2 (20.0)	1 (10.0)
	31	47			1 (10.0)	6 (60.0)	3 (30.0)
Exp. II	Immediately before HST1
	26	—	5 (41.7)	7 (58.3)
	Immediately before HST2
	26	37	1 (8.3)	8 (66.7)	3 (25.0)
	26	39.5		2 (13.3)	10 (66.7)	3 (20.0)
	26	42			4 (28.6)	7 (50.0)	3 (21.4)
	26	44.5				5 (41.7)	7 (58.3)
	26	47			1 (6.7)	5 (33.3)	9 (60.0)
	26	49.5				1 (7.7)	9 (69.2)	3 (23.1)
	26	52						11 (78.6)	2 (14.3)	1 (7.1)

Eggs of I #1 and II #1 were used for cytological observations in experiments I and II, respectively. Note. Sample eggs were fixed at 5 sec before the last HST. , HST1 has already been applied. Ap, a period during which the two pronuclei are approaching each other before forming a zygote; Z, zygote stage; P, prophase; PM, prometaphase; M, metaphase; A, anaphase; T, telophase. E, early stage; L, late stage. a, inseminated eggs were maintained at 20.0°C.