Modulating infestation rate of white fly (Bemicia tabaci) on okra (Hibiscus esculentus L.) by nitrogen application

Abstract

Pests are major factor affecting the crop yield, quality, and esthetic value. Although pest resistance is genetically controlled, it is mediated through physiological and biochemical processes interrelated with the nutritional status of the plant. Nutrition of plant may determine its resistance or susceptibility to pests. An experiment was conducted to determine whether and up to what extent varying concentrations of N modulate the infesting rate of whitefly on Okra (Hibiscus esculentus). Twenty-one-dayold okra plants were subjected to five concentrations of 4, 8, 12, 16, and 20 mM N for 30 days. Number of eggs, nymph were counted on each plant after every 4 days. Growth and yield of okra plants increased with increasing supply of N but it decreased slightly at the highest level of N (20 mM). Leaf soluble proteins, amino acids, and soluble sugars were determined on fresh weight basis. From these results, it is clear that increasing N level increased the biosynthesis or accumulation of protein, free amino acid, and sugars that might have attracted more whitefly for feeding.

Bemisia tabaci (Gennadius) population density and pupal size are dependent on rootstock and nitrogen in hydroponic tomato crop

“…Plant N fertilization may increase the availability of free amino acids, soluble sugars and proteins for phloem‐feeding insects, which in turn may affect the population density growth of these insects (Bi et al ., ; Athar et al ., ). Because plant N status affects the free amino acid content, the amount of aspartate, glutamate and arginine (predominant amino acids in cotton phloem sap) was decreased at a lower N compared with the high N treatment (Crafts‐Brandner, ).…”

“…tabaci nymphs was shown to be higher on plants supplied with 205 and 335 mg/L N than on plants supplied with 75 mg/L N. According to Athar et al . (), the nymphal density of B . tabaci 28 DAI was highest on okra plants supplied with 336 mg/L N, lower on okra plants supplied with 224 and 280 mg/L N and the lowest on okra plants supplied with 112 and 56 mg/L N. Similarly, Jauset et al .…”

“…The results of a study on okra indicated that increasing the N application rate increased the biosynthesis or accumulation of leaf soluble proteins, free amino acids and soluble sugars that might attract B . tabaci individuals for feeding (Athar et al ., ). The number of adult and immature individuals of B .…”

“…Plant nitrogen (N) content, which mainly depends on N fertilization, is one of the factors influencing whitefly infestations on agricultural crops (Tripp et al ., ; Jauset et al ., , ; Bi et al ., ; Athar et al ., ; Žanić et al ., ). The results of a study on okra indicated that increasing the N application rate increased the biosynthesis or accumulation of leaf soluble proteins, free amino acids and soluble sugars that might attract B .…”

Bemisia tabaci MED Population Density as Affected by Rootstock-Modified Leaf Anatomy and Amino Acid Profiles in Hydroponically Grown Tomato

“…Dietary nitrogen (N) is one of the factors influencing whitefly infestations of agricultural crops (Jauset et al, 1998 , 2000 ; Bi et al, 2001 ; Athar et al, 2011 ; Žanić et al, 2011 ). In phloem sap, N is present mainly in the form of free amino acids, and the sap also contains soluble proteins (Ziegler, 1975 ).…”