Biochemical basis of plant-insect interaction in arid horticulture crops: a scientific review

Plants  are  persistently  confronted  to  both  abiotic  and  biotic  stresses  that 
drastically  reduce  their  productivity.  Plant  responses  to  these  stresses  are 
multifaceted  and  involve  copious  Biochemical,  physiological,  molecular, molecular  and  cellular  adaptations.  Recent  evidence  shows  that  simultaneous occurrence  of  abiotic  and  biotic  stress  can  have  a  positive  effect  on  plant performance by reducing the susceptibility to biotic stress which is a positive sign  for  arid  horticulture  crops.  Some  of  these  adaptations  specifically biochemical  adaptations  become  the  source  of  plant  defense  mechanisms against  biotic  stresses  like  insect"s  pest  and  diseases.  These  biochemical adaptations/mechanisms includes production of secondary metabolites of plant defense against the biotic stresses especially against insects are wide spread and highly  dynamic,  and  are  mediated  the  response  directly  or  indirectly  in  arid horticultural  crops.  Production  of  secondary  metabolites  viz.  terpenes, phenolics, flavonoids, alkaloids, N & S containing compounds is constitutive as well as inducible through mild stress caused by insect damage to plants which leads  to  affect  the  feeding,  growth  and  survival  of  the  insect.  Quality  and quantity of constitutive secondary metabolites production is species as well as cultivar specific and can be expressed as signature of particular plant or species and leads to the phenomenon of host-plant interaction or host-plant resistance. This  phenomenon  of  host  plant  resistance  to  insect  can  be  exploited  for development  of  crop  cultivars  which  readily  produce  the  inducible  response upon  mild  infestation  and  can  perform  as  one  of  the  of  integrated  pest management  for  sustainable  arid  horticulture  crop  production.  This  review presents  overviews  about  these  constitutive  and  inducible  responses  towards biochemical adaptations in arid horticulture crops to protect themselves against insects.