Bioenergetic considerations in breeding for insect and pathogen resistance in plants

Abstract

The bioenergetic cost (glucose requirement to provide carbon skeletons and energy production) for the synthesis of 35 chemicals implicated as phytoalexins in combating fungal and bacterial infections as well as the alMochemicals responsible for non-preference or antibiosis in insect-plant interactions were calculated. Heat of combustion values which represent the intrinsic energy content of the molecule for these chemi-. cals, were also computed. The results indicate that the energetic cost of the chemicals responsible for genetic resistance is not exceptionally higher. In fact, they are comparable to those of many fatty acids found in plants. Though the concentration of the chemicals responsible for resistance is low in plant tissues, the total amount per hectare is quite high and consequently the plant resources that go to produce these are high.

Host-pathogen interaction between spring wheat and Septoria nodorum with reference to resistance breeding

“…Resistance to pathogens involves diverse physiological, histological, and biochemical mechanisms which can be effective before the physical contact between host and pathogen or induced after parasitic attack (Russell 1978 Kimpel 1981) suggest that the expression of active defence mechanisms is an energy-requiring biosynthetic process, which is likely to deprive host energy. This suggestion has recently been confirmed by yield experiments (Smedegärd-Petersen 1982) which show a yield reduction in barley after inoculation with avirulent fungi and by bioenergetic calculations made by Mitra and Bhatia (1982). Vanderplank (1963Vanderplank ( , 1968 divided resistance to plant pathogens into two types, horizontal and vertical.…”

Distinguishing Proof and Utilization of Resistance of Insect Pests in Grain Legumes: Progress and Limitations

“…Some mechanisms of plant resistance may involve the diversion of plant morphological traits or biochemical traits for the production of defense chemicals and other physiological processes that helps in obtaining yield (Mooney et al 1983). Although concentration of natural defense chemicals responsible for resistance is low in plant tissues, the total amount per hectare may be high (Mitra and Bhatia 1982). Some plant defense chemicals also affect the food nutrition quality.…”