The cyst nematode Heterodera latipons Franklin, 1969 (Nemata: Heteroderidae): hatching behavior and development on wheat in arid and semiarid regions in Turkey

The cyst nematode Heterodera latipons Franklin, 1969 (Nemata: Heteroderidae) is an economically important sedentary plant-parasitic nematode which limits the production of cereal crops around the world. It is an important pest on wheat and can be found globally in different growing areas, especially in the Mediterranean region. Developing an understanding of its physiological behavior (senescence, quiescence, and cryptobiosis), development [second-stage juveniles (J2) and immature and mature females], and population dynamics under field conditions is needed to create an appropriate control strategy. The experiments were conducted at Karaisali, a semiarid region in Adana Province, and at Derik, an arid region in Mardin Province, during the 2015-2016 and 2016-2017 growing seasons. The results indicated that the emergence of J2 of H. latipons in the soil rhizosphere occurred from late December to mid-January in the semiarid region, while they were mostly observed through March in both regions when the average temperature was around 10 degrees C. The white (immature) females were seen between mid-February and mid-March in both experimental seasons in the arid and semiarid regions, and they were mainly observed in April when the temperature was above 15 degrees C during both seasons in the arid region. The results showed that H. latipons produces only one generation in each wheat growing season, and the developmental stages of this nematode species are closely related to the ecological and edaphic factors of host plant development. Moreover, the development of J2 and immature females of H. latipons took longer in the semiarid region than in the arid region owing to plant and root growth and edaphic factors, especially soil temperature and moisture. Understanding the physiological behavior and biological stages of this nematode will be useful for developing nematode control strategies to keep H. latipons populations below economic damage levels.