RICE RATOONING - IRRI books - International Rice Research Institute

INHERITANCE OF RATOONING ABILITY IN CHINESE VARIETIES 243Table 3. The comparison of h 2 in ratooning ability of the recriprocals of different parents.NParent Ratooning ability (%)h 2NTaster parentShu-Fong No. 1 (11)Ai-Nan-Zaoto betestedNormalReciprocalNormalReciprocalTai-Guao-Dao Shong-Zao-Xian Hon-Mei-ZaoXuan No. 26–64.54 ± 30.92 65.56 ± 14.74 70.75 ± 14.07F = 0.76F = 1.49** F = 1.55**12.21 ± 25.94 23.01 ± 19.10 41.82 ± 17.00F = 1.06F = 1.134 F = 1.264**76.41 ± 14.07F = 1.618**13.01 ± 21.52F = 1.070*Significant at 5% level. **Significant at 1% level.1.55 ± 21.93F = 1.34738.52 ± 20.69F = 1.239*57.03 ± 16.049F = 1.399**interaction. Using Mather and Jinks’ (4) procedures, six generations of each crosscombination and its reciprocals were used to estimate the genetic parameters andcomparisons were made between corresponding estimates of these parametersobtained from reciprocal crosses. Various components of genic effects in thereciprocal crosses have been estimated as in Table 4. This indicates that1) the additive [d] in crosses with Ai-Nan-Zao are all negative and highlysignificant, which shows that Ai-Nan-Zao will decrease ratooning ability;2) Shu-Fong No. 1 (11) mated with Tai-Guao-Dao-Xuan. Shong-Zao-XianNo. 26 or Hon-Mei-Zao shows additive effects [d] which are extremelysignificant except in Shu-Fong No. 1 (11)/ Hon-Mei-Zao;3) the crosses produced by parents possessing a certain degree of ratooningability show different genic effects [m], [h], [i], [j], and [l], among filialgenerations from different parents of and between the reciprocals of thesame parents.Cytoplasmic effects and nucleocytoplasmic interaction in ratooning abilityTo understand further how the cytoplasm affects the various components of geniceffect in ratooning ability, the difference between the reciprocals in the variouscomponents of heredity is estimated from the data in Table 4 by the formula of 1/2[reciprocal 2 minus normal (l)], and listed in Table 5.In the column of component of heredity in Table 5,1/2 (m 2 -m 1 ) is equal to themean of differences between the reciprocals in average genic effects, that is, thecytoplasmic effects. 1/2([d] 2 -[d] l ) equals the mean of difference, which subtractsnormal additive [d]l from the reciprocal one [d]2. As 1/2([d] 2 - [d] 1 ) is equal to zero,there seems to be no additive-cytoplasm interaction in the crosses under investigation.1/2([h 2N - [h] 1 ) equals the interaction of dominance with the cytoplasm. l/2([i] 2-[i] 1 , 1/2([j] 2 - [j] l , 1/2([1] 2 - [1] 1 ) are the interactions of additive/additive,additive/ dominance, and dominance/ dominance with the cytoplasm, respectively.Results are obtained by T testing. Tai-Guao-Dao-Xuan’s cytoplasmic effect appearsto be positive for Shu-Fong No. 1 (11) and negative for Ai-Nan-Zao, and they are allhighly significant. Shong-Zao-Xian No. 26 shows extremely significant negativeeffect for Shu-Fong No. l(11), while Hon-Mei-Zao shows no significant cytoplasmiceffect for Shu-Fong No. 1(11) but some cytoplasmic effects for Ai-Nan-Zao.