Supplementation of Maize- and Cowpea Seed-Based Artificial Diets with Diverse Pollen Sources Affects the Demographic Features of Leucania loreyi (Duponchel, 1827) (Lepidoptera: Noctuidae)

<i>Leucania loreyi</i> (Duponchel, 1827) is a major lepidopteran pest that infests a wide range of crops worldwide. Effective mass production of insects for pest management programs depends on the availability of suitable artificial diets. Here, we evaluated 14 artificial diets (D1-D14) formulated from maize or cowpea seeds (19.5 g) plus standard diet components and supplemented with 1 g of pollen from different sources (rapeseed, date palm, maize, common hollyhock, saffron, and honey bee), along with control diets. We assessed their effects on demographic traits of <i>L. loreyi</i>. The maize seed-maize pollen diet (D3) and the cowpea seed-maize pollen diet (D10) produced the shortest developmental times (37.53 and 38.10 days, respectively), whereas the maize seed-saffron pollen (D5) and cowpea seed-saffron pollen (D12) diets resulted in the longest development (45.83 and 45.56 days, respectively). Diet also D3 yielded the shortest adult and total pre-oviposition periods (APOP and TROP), the greatest female longevity, and the highest fecundity and net reproductive rate (<i>R</i>₀) (801.69 and 88.69 offspring, respectively). In contrast, diet D12 produced the lowest fecundity and <i>R</i>₀ (339.73 and 68.15 offspring, respectively). Consistent with these patterns, D3 generated the highest intrinsic rate of increase (<i>r</i>) and finite rate of increase (<i>λ</i>), while diets D5 and D12 were associated with lower population growth rates. Cluster analysis further identified D3 as the most nutritionally favorable formulation under our experimental conditions, supporting its potential utility for large-scale <i>L. loreyi</i> rearing.