Neonate sensitivity plants

External excitatory and inhibitory stimuli for acceptance or rejection of food are modified by the internal condition of the insect (e.g., hunger). This modification can cause a given stimulus to produce different responses, depending upon the internal condition of the insect. After host acceptance, there are still obstacles that the insect must overcome in order to survive, grow, and reproduce. These hurdles include allelochemicals that block nutrient availability, defenses of susceptible plants, poor balance of essential nutrients, and less than optimal water content. Neonate larvae may be far more sensitive to some of these obstacles than older ones. 

A much slower transport process which catalyzes the net uptake of ATP has been demonstrated in liver [42,43] and heart mitochondria [44,45], and shown to be physiologically important in neonatal liver mitochondria [46,47]. The transporter s activity may be affected by hormones since it has been shown that glucagon treatment increases the total nucleotide content of subsequently isolated liver mitochondria [48]. Although initially thought to be due to rather nonspecific leakiness of mitochondrial membranes or unidirectional transport on the adenine nucleotide carrier, its lack of sensitivity to membrane potential, and its almost absolute dependence on the presence of Mg and phosphate suggest that the observed activity is due to a separate transporter [42]. Net nucleotide uptake in plant mitochondria is much more marked but has a similar dependence on Mg " and phosphate in the media [49]. 

Reese (37) has studied nutrlent-allelochemical Interactions using diets supplemented by plant extracts. He has concluded that many of the deleterious effects may be due primarily to various Interactions between these allelochemical and essential nutrients. It Is Important to not only consider the presence of nutrients, but also the bloavallability of these nutrients to the phytophagous Insect. He cited findings where neonate larvae were found more sensitive to plant allelochemicals than older larvae, and Interpreted the greater resistance of the older larvae In terms of Increasing capability to utilize available nutrients, probably because of the Induction of enzymatic detoxification systems. 

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