The effects of six applied N treatments differing by rates and frequencies of application on the yield andquality of pepper (Capsicum annuum var. annuum L. ‘Anaheim Chili’) grown for seed was studied. The timing of Napplications was based on crop phenology, leaf petiole nitrate-nitrogen concentrations (NO3-N) minimum thresholds,and scheduled calendar applications of fixed amounts of N. Solubilized NH4NO3 was applied through a trickleirrigationsystem to ensure uniform and timely applications of N. Rate of mature (green and red) fruit productionwas unaffected by any treatment except weekly applications of 28 kg·ha-l of N, which stopped production of maturefruit before all other treatments. Early season floral bud and flower production increased with increasing amountsof N. The two highest total N treatments produced more floral buds and flowers late in the season than the othertreatments. Total fruit production was maximized at 240 kg N/ha. Differences in total fruit production due to frequencyof N application resulted at the highest total N level. Red fruit production tended to be maximized with total seasonalapplied N levels of 240 kg·ha-1 and below, although weekly applications of N reduced production. Total seed yieldwas a function of red fruit production. Pure-1ive seed (PLS) production was a function of total seed production.Nitrogen use efficiency (NUE) for red fruit production also decreased with N rates >240 kg·ha-1, but PLS yield andNUE decreased in a near-linear fashion as the amount of total seasonal applied N increased, regardless of applicationfrequency. Season average NO3-N (AVE NO3-N) values >4500 mg·kg-1 had total seed and PLS yields less than thosetreatments <4000 mg·kg-l. Six-day germination percentage was reduced with weekly N applications of 14 kg·ha-1.Seed mass was reduced with weekly N applications of 28 kg·ha-1. Final germination percent, seedling root lengthand weight, and field emergence were unaffected by any of the N treatments. These findings indicate that differentN management strategies are needed to maximize seed yield compared to fruit yield and, therefore, there may be anadvantage to growing ‘Anaheim Chili’ pepper specifically for seed.
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