Cd. Johnson et Dr. Decoteau, NITROGEN AND POTASSIUM FERTILITY AFFECTS JALAPENO PEPPER PLANT-GROWTH, POD YIELD, AND PUNGENCY, HortScience, 31(7), 1996, pp. 1119-1123
The influence of N and K rates in Hoagland's nutrient solution on Jala
peno pepper (Capsicum annuum L.) plant growth and pod production was d
etermined on greenhouse-grown plants in sand culture. Varying the rate
s of N (1 to 30 mM) and K (1 to 12 mM) in Hoagland's solution identifi
ed optimum concentrations for Jalapeno plant growth and pod production
. Two experiments mere conducted to determine Jalapeno pepper sensitiv
ity to differential fertilization. In the experiment seeded in April,
nutrient treatments began at transplanting, and in the one seeded in M
ay, treatments began after all plants had flower buds and half had flo
wered. Biomass and pod production per plant responded curvilinearly to
N rate in both experiments. Optimum N rate for pod yield was 15 mM. N
itrogen rate affected pungency of pods only in the first experiment, w
ith 1 mM N reducing capsaicin levels in fruit compared to other N rate
s. Biomass, fruit count, and fruit weight per plant increased linearly
with increasing K rate in the first experiment and curvilinearly with
K rate in the second experiment. The optimum K rate for pod yield was
6 mM. Potassium rates did not affect pod pungency. Jalapeno peppers g
rown in sand culture required 15 mM N and at least 3 mM K for optimum
pod production.