Screening of tropical inbred lines for drought tolerance based on secondary traits in maize (Zea mays L.)

  • P. Suthamathi and G. Nallathambi tnau
Keywords: Maize, moisture stress, screening

Abstract

In the present study, 63 tropical maize inbred lines were screened for four drought related traits viz., relative water content, root volume, root length and anthesis silking interval at three different stages of induced stress at vegetative, pre anthesis and at anthesis stages. Where earliness for avoiding terminal drought is desired, the genotypes with short ASI could be used. In the present investigation, fourteen inbreds showed < 2 days, anthesis silking interval when compared with parental means (5.45 days). Among them seven inbreds viz., UMI 285, UMI 917, UMI 1024, UMI 1056, UMI 1060 and UMI 1096 had reduced ASI of one day. The anthesis silking interval became shorter under drought and selection seemed to have led to significantly faster spikelet and ear growth at flowering, but also to reduction in final spikelet number. Relative Water Content (%) was more during vegetative stage stress compared to pre anthesis and at anthesis stages. The comparison of RWC means in all three stages showed that the level of RWC of leaves were significantly increased in nine genotypes and UMI 233 recorded the highest RWC (87.27%). Considering root length and root volume across the stages, root length was increased slightly in pre and at anthesis stages but root volume decreased during post anthesis stage among the genotypes. In the present investigation, sixty three tropical inbreds screened for drought tolerance, a total of 14 inbred lines were selected based on RWC (%), root length, root volume and anthesis silking interval (<3 days) for utilizing in hybridization.

 

Author Biography

P. Suthamathi and G. Nallathambi, tnau
PB&G
Published
03-04-2018
Section
Research Article