Who coined the term 'heterosis'?

Which is the oldest method of plant breeding for crop improvement?

Select the appropriate option for evaluation and selection of parents in plant breeding.

Select the correct option for $Saccharum$ $barberi$ and $Saccharum$ $officinarum$.
$I -$ Low sugar content
$II -$ High sugar content
$III -$ Low yield
$IV -$ High yield
$V -$ Grown in North India
$VI -$ Grown in South India
$Saccharum$ $barberi$ $\quad$ $Saccharum$ $officinarum$

Modern plant breeding started in

The main aim of plant breeding is