Abstract No. Oral–70
EFFECT OF ALIEN CYTOPLASM AND NUCLEAR GENES IN ALLOPLASMIC
X EUPLASMIC AND EUPLASMIC X EUPLASMIC HYBRIDS
IN UPLAND COTTON (Gossypium hirsutum)
O.P. Tuteja
CICR Regional Station, Sirsa, India
Cotton is an often cross pollinated crop with a considerable amount of heterosis. first conventional
hybrid was developed in India. In other countries hybrid seed production by conventional method is not
possible as it is labour intensive. Several alternate methods for emasculation are available, of which GMS
and CMS systems are quite effective. In case of other methods there is always a chance of pistil damage
and anthers are not completely eliminated. In case of GMS and CMS systems only CMS system may be
more effective, as in GMS system 50% of the plants of have to be rouged out at flowering. Use of CMS
line approach may prove to be the best method for hybrid seed production in cotton. The success in
development of CMS based hybrid largely depends on availability of stable male sterile cytoplasm and
the effective restorer lines. However, the CMS system could not be exploited commercially because the
alien cytoplasm and nuclear genes exhibited their deleterious effect on yield and related traits. The study
was oriented to find out the effect of alien cytoplasm in alloplasmic x euplasmic hybrids in first
experiment, and the effect of alien cytoplasm as well as of nuclear genes in the alloplasmic x euplasmic
and euplasmic x euplasmic hybrids respectively, in the second experiment. The hybrids for both the
experiments were produced using Line x Tester mating system. Yield and contributing traits exhibited
superiority of conventional euplasmic x euplasmic hybrids over CMS based alloplasmic x euplasmic
hybrids in both the experiments and over GMS based euplasmic x euplasmic hybrids in second
experiment. CMS based alloplasmic x euplasmic hybrids were superior over GMS based euplasmic x
euplasmic hybrids in the second experiment for yield and boll weight. However, for fibre quality traits
the trend of performance was variable. Alien cytoplasm and nuclear genes did not exhibit deleterious
effects for fibre quality related traits, even though a gain was reported in some of the CMS based
alloplasmic x euplasmic hybrids for 2.5% span length and uniformity ratio over the euplasmic x
euplasmic hybrids in the first experiment. In the second experiment, CMS based alloplasmic x euplasmic
hybrids expressed their superiority over the GMS based euplasmic x euplasmic hybrids for most of the
fibre quality traits. The average performance of conventional euplasmic x euplasmic hybrids were
unambiguously superior over the two type of hybrids for yield and its component traits.
46
World Cotton Research Conference on Technologies for Prosperity