Pathogenicity and chemical control of Alternaria sp. on date palm (Phoenix dactylifera L.)

Abstract

Recently, a wide range of symptoms including light yellow lesions gradually turning into brown stripes were noticed on date palm leaves in Iraq. In this context, the aim of this study were to isolate the phytopathogens associated with these symptoms, evaluate their pathogenicity and assess the efficacy of two fungicides (Score and Pentanol) under in vitro and in vivo conditions. Two fungal species (Alternaria sp. and Fusarium sp.) were isolated from the symptomatic leaves of date palm. The results of pathogenicity tested proved the ability of Alternaria sp. inoculated separately or in combination with Fusarium sp. to infect the leaves of date palm trees with disease severity index (DSI) values of 67.33% and 65.99%, respectively. The effect of Score (88.76%) and Pentanol (82.91%) against Alternaria sp. was examined by poisoned food technique, which leads a significant increase in mycelial growth inhibition (for 300% of commercial recommended dose of fungicide). Test results indicate that prophylactic spraying of date palm leaves with Score or Pentanol effectively controlled Alternaria sp. with DSI values of 22.65% and 17.87%, respectively. To control Alternaria sp. in field within integrated pest management strategies, chemical control using Score or Pentanol should be taken in consideration.

Preparation and properties of multifunctional phenoxyacetate-based ionic liquids and their application in citrus bacteriostatic preservation

“…The method of soaking fruit with liquid medicine was adopted. 32,33 With 200 mg L À1 2,4-D as the control group, water as the CK group, and 200 mg L À1 DIL-3 as the experimental group, the citrus was soaked for three minutes and then dried, and then stored in polyethylene fresh-keeping bags at room temperature with a 4 mm circle of Penicillium italicum in each bag. The disease index and control effect were calculated by observing the incidence of citrus after 21 days.…”