Urea and Trichoderma harzianum Loaded Clay-Polymer Composite in Conjunction with Farmyard Manure Sustains Soil Moisture and Nitrogen Availability to Manage Fusarium-Meloidogyne Disease Complex in Lentil (Lens culinaris)

Abstract

ABSTRACT The present investigation reports the development and characterization of a clay-polymer composite loaded with urea and Trichoderma harzianum (UTCPC) to enhance soil moisture and nitrogen availability and manage wilt-nematode complex in lentil grown in residual moisture after rainfed rice. The Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) characterization proved successful synthesis of UTCPC. The bentonite clay (8% w w−1) and Th concentration (10% w w−1) were optimized based on the maximum spore count of the UTCPC and viability of the Th spores at one month of storage at room temperature. The incubation and pot culture experiments were laid out in a completely randomized design (CRD) with six N levels replicated thrice in combinations with UTCPC. Under incubation experiment, the treatment of 100% N through farmyard manure (FYM) along with UTCPC application (T3) resulted in the highest soil moisture (18.5%) and lowest nitrate (NO3-N) content (42%) at 6 and 10 days after incubation, respectively, suggesting its sustained moisture-retaining and slow nitrate (NO3-N) release properties of the UTCPC. Under pot experiment, the treatment T3 expressed the highest soil moisture (28.8%) and NO3-N (17.6 kg ha−1) content even at 60 days after sowing. The disease severity index of all the treatments comprising UTCPC with or without nutrient application was significantly lower than the untreated soil. The lowest population of Fusarium spp. (13.8%) and Meloidogyne spp. (8%) were observed in T3. Therefore, UTCPC can be considered as an eco-friendly agri-input in enhancing moisture retention and sustaining nutrient release to the soil as well as providing biocontrol agents to manage Fusarium-Meloidogyne complex in lentil.