Population Dynamics and Damage Threshold of Meloidogyne incognita to the Dinsire Hot Pepper Variety

Abstract

Predicting the damage caused by certain nematode population densities is crucial in deciding whether or not to cultivate pepper and selecting the most suitable management strategies. To understand the relationship between the initial nematode density (Pi) and the final nematode population (Pf), and the damage potential of Meloidogyne incognita to var. Dinsire, a study was conducted under greenhouse conditions. A geometric series of 13 initial densities (0, 0.0625, 0.125, 0.25, 0.5, 1, 2, 4, 8, 16, 32, 64, 128 J2 (g soil) -1 ) of M. incognita was subjected to Dinsire. The treatments were arranged in a randomized complete design with four replications and terminated after 120 days of nematode inoculation. This study showed that the final nematode population, plant growth, and yields decreased as initial nematode inoculums increased. Maximum suppression fresh weight of shoot (43.8%) and fruit (52%) was recorded at Pi ≥ 8 J2 (g soil) -1 . The analysis of Seinhorst's yield loss model indicated the highest tolerance limit (T=0. 64 egg + J2 (g soil) -1 ) recorded for leaf number, while the relative minimum yield (m) of 0.91 and 0. 86 were the highest m values for root length and shoot height, respectively. Furthermore, the maximum multiplication rate (a) and population densities (M) were estimated as 8813.2 and 3420.1 (eggs and J2 (g soil) -1 ), respectively. Therefore, evaluating hot pepper varieties for resistance using a wide range of Pi could generate more reliable information on the host status of pepper varieties.